Publications by authors named "Han-Ik Cho"

76 Publications

Subclinical steatohepatitis and advanced liver fibrosis in health examinees with nonalcoholic fatty liver disease (NAFLD) in 10 South Korean cities: A retrospective cross-sectional study.

PLoS One 2021 24;16(11):e0260477. Epub 2021 Nov 24.

MEDIcheck LAB, Korea Association of Health Promotion, Seoul, Korea.

Background: Nonalcoholic steatohepatitis (NASH) has a risk of progressing to cirrhosis. The prevalence of NASH and its associated risk factors in community populations are relatively unknown. This study aimed to determine the prevalence of NASH and advanced liver fibrosis using magnetic resonance elastography (MRE), and determine those risk factors in health examinees with asymptomatic fatty liver.

Methods: This study consecutively selected subjects who underwent health checkups at 13 health-promotion centers in 10 Korean cities between 2018 and 2020. Hepatic steatosis and stiffness were assessed using ultrasonography and MRE, respectively. Stages of liver stiffness were estimated using MRE with cutoff values for NASH and advanced liver fibrosis of 2.91 and 3.60 kPa, respectively.

Results: The overall prevalence of NASH and advanced liver fibrosis in the subjects with fatty liver were 8.35% and 2.04%, respectively. Multivariate logistic regression analysis indicated that central obesity (OR = 5.12, 95% CI = 2.70-9.71), increased triglyceride (OR = 3.29, 95% CI = 1.72-6.29), abnormal liver function test (OR = 3.09, 95% CI = 1.66-5.76) (all P<0.001), and decreased high-density lipoprotein cholesterol (OR = 5.18, 95% CI = 1.78-15.05) (P = 0.003) were associated with NASH. The main risk factor for advanced liver fibrosis was diabetes (OR = 4.46, 95% CI = 1.14-17.48) (P = 0.032).

Conclusion: NASH or advanced liver fibrosis is found in one-tenth of health examinees with asymptomatic fatty liver. This suggests that early detection of NASH should be considered to allow early interventions such as lifestyle changes to prevent the adverse effects of NASH and its progression in health examinees with asymptomatic fatty liver.
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http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0260477PLOS
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8612540PMC
November 2021

Reference interval and the role of plasma oligomeric beta amyloid in screening of risk groups for cognitive dysfunction at health checkups.

J Clin Lab Anal 2021 Sep 3;35(9):e23933. Epub 2021 Aug 3.

MEDIcheck LAB, Korea Association of Health Promotion, Seoul, Korea.

Background: Alzheimer's disease (AD) has a prolonged preclinical stage characterized by cognitive dysfunction. Simple, reliable, and noninvasive biomarkers reflecting the pathogenesis of AD are needed for screening cognitive dysfunction in primary health care. The aims of this study were to determine (1) the potential utility of the Multimer Detection System-Oligomeric Amyloid-β (MDS-OAβ) value in cognitive assessments and (2) the reference interval (RI) of plasma MDS-OAβ values in the general population.

Methods: This prospective study consecutively recruited 1,594 participants who underwent health checkups including cognitive function examination at 16 health-promotion centers in Korea between December 2020 and January 2021. The inBlood OAβ test (PeopleBio, Gyeonggi-do, Republic of Korea) was utilized to quantify MDS-OAβ values in plasma. The reference subjects were obtained among those with normal general cognition on cognitive screening tools. RIs were established according to the CLSI C28-A3 guidelines.

Results: The median MDS-OAβ value was higher in subjects with Korean Dementia Screening Questionnaire-Cognition (KDSQ-C) scores ≥8 than in those with KDSQ-C scores of 6-7 (P = 0.013). The median MDS-OAβ value was higher in subjects with Mini-Mental State Examination for Dementia Screening (MMSE-DS) scores of 21-26 than in those with MMSE-DS scores ≥27 (P = 0.011). The RI (one-side upper 95th percentile) of the MDS-OAβ value was 0.80 ng/mL (95% confidence interval = 0.78-0.82) in those aged ≥50 years.

Conclusions: The plasma MDS-OAβ value reflects cognitive function as assessed using the KDSQ-C and MMSE-DS. RIs obtained from a large and cognitively healthy community-based sample are presented.
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http://dx.doi.org/10.1002/jcla.23933DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8418474PMC
September 2021

Nationwide seroprevalence of antibodies to SARS-CoV-2 in asymptomatic population in South Korea: a cross-sectional study.

BMJ Open 2021 04 24;11(4):e049837. Epub 2021 Apr 24.

MEDIcheck LAB, Korea Association of Health Promotion, Seoul, Republic of Korea.

Objective: Asymptomatic active infection might be an important contributor to the COVID-19 outbreak. Serological tests can assess the extent of exposure and herd immunity to COVID-19 in general populations. This study aimed to estimate the nationwide seroprevalence of SARS-CoV-2 antibodies according to age, sex and clinical status in South Korea.

Design, Setting And Participants: This cross-sectional study randomly selected health examinees who underwent health check-up at 16 health promotion centres in 13 Korean cities across the country between late September and early December 2020. Residual serum samples were obtained from 4085 subjects (2014 men and 2071 women). Antibodies to SARS-CoV-2 were measured by electrochemiluminescence immunoassay using Elecsys Anti-SARS-CoV-2 (Roche Elecsys, Mannheim, Germany).

Primary And Secondary Outcome Measures: Fisher's exact test was used to compare the seroprevalence according to sex, age group and region. The relative risks of being seropositive according to the characteristics of the study subjects were analysed using logistic regression analysis.

Results: The overall seroprevalence of anti-SARS-CoV-2 was 0.39% (95% CI=0.20% to 0.58%): 0.30% (95% CI=0.06% to 0.54%) for men and 0.48% (95% CI=0.18% to 0.78%) for women. The rate of anti-SARS-CoV-2 positivity varied significantly between different regions of Korea (p=0.003), but not with age group, sex, or the statuses of obesity, diabetes, hypertension or smoking.

Conclusions: Most of the Korean population is still immunologically vulnerable to SARS-CoV-2, but the seroprevalence has increased relative to that found in studies performed prior to September 2020 in Korea.
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http://dx.doi.org/10.1136/bmjopen-2021-049837DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8076630PMC
April 2021

Prevalence of liver fibrosis and associated risk factors in the Korean general population: a retrospective cross-sectional study.

BMJ Open 2021 03 24;11(3):e046529. Epub 2021 Mar 24.

MEDIcheck LAB, Korea Association of Health Promotion, Seoul, South Korea.

Objectives: The health burden of chronic liver disease is increasing worldwide. Its main histological consequence is liver fibrosis, and eventually cirrhosis. This process is rarely diagnosed at the pre-cirrhotic stage due to it being asymptomatic. Little is known about the prevalence of liver fibrosis and associated risk factors in the general population. The aims of this study were to determine the prevalence and distribution of liver fibrosis using magnetic resonance elastography (MRE), as well as the risk factors associated with liver fibrosis in the asymptomatic general population.

Design, Setting And Participants: This cross-sectional retrospective study consecutively selected subjects who underwent health check-ups including MRE at 13 health promotion centres in Korea between 2018 and 2020. Liver fibrosis was estimated using MRE with cut-off values for significant and advanced liver fibrosis of 2.90 and 3.60 kPa, respectively.

Primary And Secondary Outcome Measures: The Χ test was used to compare the prevalence of liver fibrosis according to sex and age groups. Multivariable logistic regression analyses were performed to identify the factors for significant and advanced liver fibrosis.

Results: Among the 8183 subjects, 778 (9.5%) had ≥significant fibrosis (≥2.9 kPa), which included 214 (2.6%) subjects with ≥advanced fibrosis (≥3.6 kPa). Multivariable analysis revealed that liver fibrosis was associated with age (OR=1.34, 95% CI=1.18 to 1.51), male sex (OR=3.18, 95% CI=1.97 to 5.13), diabetes (OR=2.43, 95% CI=1.8 to 3.28), HBsAg positivity (OR=3.49, 95% CI=2.55 to 4.79), abnormal liver function test (OR=1.9, 95% CI=1.49 to 2.42) and obesity (OR=1.77, 95% CI=1.35 to 2.32) (all p<0.001), as well as metabolic syndrome (OR=1.4, 95% CI=1.05 to 1.87) (p=0.024).

Conclusions: The prevalence of significant or more liver fibrosis was high in the Korean general population and much higher among individuals with risk factors. This suggests that screening of liver fibrosis should be considered in general population, especially among high-risk groups.
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http://dx.doi.org/10.1136/bmjopen-2020-046529DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7993338PMC
March 2021

Reference interval and the role of soluble suppression of tumorigenicity 2 (sST2) in subclinical cardiac dysfunction at health checkups.

J Clin Lab Anal 2020 Nov 7;34(11):e23461. Epub 2020 Jul 7.

MEDIcheck LAB, Korea Association of Health Promotion, Cheongju, Korea.

Background: Soluble ST2 (sST2) is known to predict adverse outcomes and death in individuals with established heart failure. However, the role of sST2 testing in the general population has not been established. The aims of this study were to determine the reference interval (RI) and the clinical utility of sST2 in subclinical cardiac dysfunction in general population.

Methods: This cross-sectional study consecutively selected 41,806 general subjects at health checkups who underwent echocardiography and sST2 testing at 16 health promotion centers in 13 Korean cities. The reference subjects were obtained among those with normal findings in echocardiography. Sex-specific RIs were established according to the CLSI C28-A3 guidelines. sST2 was measured using immunoassay with the Presage ST2 assay (Critical Diagnostics).

Results: In the general subjects, age, sex, BMI, systolic blood pressure, blood glucose, creatinine, liver function, and triglycerides were associated with the sST2 levels. The RI for sST2 was higher in males (≤49.6 ng/mL, 95% CI = 48.5-51.5) than in females (≤44.5 ng/mL, 95% CI = 43.5-45.6) and higher in subjects aged < 40 years than ≥ 40 years in both sexes. The sST2 levels were 29.1 ± 10.7 (mean ± SD) and 29.1 ± 14.4 ng/mL in the groups with normal cardiac function and subclinical cardiac dysfunction, respectively. The sST2 level was not associated with subclinical cardiac dysfunction (odd ratio = 1.002, P = .13).

Conclusions: RIs obtained from a large and echocardiography-proven healthy community-based sample are presented. Subclinical cardiac dysfunction was associated with older age, male sex, and metabolic factors but not with the sST2 level.
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http://dx.doi.org/10.1002/jcla.23461DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7676181PMC
November 2020

Diagnostic performance of Mac-2 binding protein glycosylation isomer (M2BPGi) in screening liver fibrosis in health checkups.

J Clin Lab Anal 2020 Aug 29;34(8):e23316. Epub 2020 Mar 29.

MEDIcheck LAB, Korea Association of Health Promotion, Cheongju, Korea.

Background: Mild-to-moderate fibrosis is rarely diagnosed because the disease is asymptomatic in the early stage. The serum level of Mac-2 binding protein glycosylation isomer (M2BPGi) has been found to increase with the severity of liver fibrosis. The aim of this study was to determine the diagnostic performance of M2BPGi in screening liver fibrosis using magnetic resonance elastography (MRE) as a reference standard and to compare it with using the aspartate aminotransferase-to-platelet ratio (APRI) and the Fibrosis-4 index (FIB-4) in health checkups.

Methods: This cross-sectional study consecutively selected subjects at health examinations who underwent MRE and M2BPGi testing at eight health promotion centers in Korea between January and September 2019. The serum M2BPGi level was measured using the chemiluminescence enzyme immunoassay method. The measured levels were indexed using the cutoff index (COI). COI values of M2BPGi were compared with the MRE results.

Results: The median (interquartile) values of COI for fibrosis stages F0 (normal liver stiffness), F1 (mild fibrosis), F2 (significant fibrosis), and ≥F3 (advanced fibrosis) were 0.49 (0.34-0.61), 0.48 (0.38-0.68), 0.64 (0.43-1.03), and 1.01 (0.75-1.77), respectively (P < .0001). The AUCs of the COI for the screening of fibrosis stage ≥F1, ≥F2, and ≥F3 were 0.591, 0.698, and 0.853, respectively. Using a threshold of 0.75 for COI to exclude advanced fibrosis had a sensitivity, specificity, and negative predictive value of 80.0%, 77.9%, and 98.9%, respectively. The AUC for excluding advanced fibrosis was better for M2BPGi than for FIB-4 and APRI.

Conclusion: Serum M2BPGi was useful for screening significant and advanced fibrosis in health checkups.
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http://dx.doi.org/10.1002/jcla.23316DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7439422PMC
August 2020

Distribution of hemoglobin levels and prevalence of anemia according to sex, age group, and region in 13 Korean cities.

Int J Lab Hematol 2020 Apr 12;42(2):223-229. Epub 2020 Feb 12.

MEDIcheck LAB, Korea Association of Health Promotion, Cheongju, Korea.

Introduction: The distribution of hemoglobin (Hb) levels and the prevalence of anemia are significant public health indicators. The aims of this study were to determine the distribution of Hb levels and the prevalence of anemia according to sex, age group, and region throughout Korea.

Methods: The study analyzed data on 1 159 298 subjects who received health checkups at 16 health-promotion centers in 13 Korean cities during 2018. Anemia and its severity were defined according to the World Health Organization classification for Hb levels as follows: mild anemia (11-12.9 g/dL in males and 11-11.9 g/dL in females), moderate anemia (10-10.9 g/dL in both sexes), and severe anemia (<10.0 g/dL in both sexes).

Results: The Hb level in the general sample was lower in females (13.25 ± 1.13 g/dL, mean ± SD) than in males (15.29 ± 1.22 g/dL). The overall prevalence of anemia was 6.0% (2.98% in males and 8.56% in females), and the prevalence of severe anemia was 0.92% (0.23% in males and 1.51% in females). While the prevalence of anemia increased monotonically with age in males, it was bimodal in females with two peaks at 40-49 years and ≥80 years. The highest prevalence of anemia in females aged 40-49 years was attributed to microcytic anemia, while increases in anemia prevalence in males aged ≥50 years and females aged ≥70 years were attributed to macrocytic anemia.

Conclusion: The distribution of Hb levels and the prevalence of anemia overall and by severity differ according to sex, age group, and region throughout Korea.
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http://dx.doi.org/10.1111/ijlh.13160DOI Listing
April 2020

Subclinical Iron Deficiency in Non-Anemic Individuals: A Retrospective Analysis of Korean Health Examinees.

Acta Haematol 2020 12;143(1):26-32. Epub 2019 Jul 12.

Health Promotion Research Institute, Korea Association of Health Promotion, Seoul, Republic of Korea.

Objectives: Non-anemic individuals may have undetected subclinical iron deficiency (SID). The aims of this study were to determine the prevalence of SID and identify the associated factors for SID. In addition, the screening performance of red blood cell (RBC) indices for SID in health check-ups was assessed.

Methods: This study was conducted with 16,485 non-anemic health examinees (3,567 males and 12,918 females) who underwent tests for iron variables (serum iron, total iron-binding capacity, ferritin, and iron saturation) at 16 health-promotion centers in 13 cities in Korea between January 2017 and June 2018. SID was defined as a decreased ferritin level (<24 µg/L in males and <15 µg/L in females) and either a decreased serum iron level (<44 µg/dL in males and <29 µg/dL in females) or a transferrin saturation of <20%.

Results: The prevalence rates of SID were 0.6 and 3.3% in males and females, respectively. In terms of age and sex, SID was most prevalent in males aged ≥70 years (7.8%) and females aged 15-49 years (7.6%). There were significant differences in the hemoglobin (Hb) level, white blood cell count, platelet count, mean corpuscular volume, mean corpuscular Hb (MCH), and RBC distribution width (RDW) between the SID and non-SID groups (p < 0.001). The factors associated with SID in males were older age (odds ratio, OR, 1.069, 95% confidence interval, CI, 1.03-1.109, p = 0.004), lower Hb (OR 0.58, 95% CI 0.345-0.976, p = 0.04), lower MCH (OR 0.433, 95% CI 0.298-0.629, p < 0.001), and higher RDW (OR 1.374, 95% CI 1.001-1.887, p = 0.049), while in females they were lower body mass index (BMI; OR 0.929, 95% CI 0.895-0.963, p < 0.001) and younger age (OR 0.954, 95% CI 0.945-0.963, p < 0.001), as well as lower Hb, lower MCH, and higher RDW. The AUC for the MCH (0.877, 95% CI 0.793-0.960 in males; 0.872, 95% CI 0.853-0.890 in females) indicates that the MCH at cut-offs of 29.2 and 29.3 pg are the best discriminators of SID in males and females, respectively (p < 0.001).

Conclusions: Reproductive-age females with a lower BMI and elderly males are high-risk groups for SID. MCH is a reliable RBC index for the screening of SID. For the population with defined risk factors, including females with lower BMI and elderly males, screening for SID is needed to prevent the development of anemia.
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http://dx.doi.org/10.1159/000500630DOI Listing
April 2020

Plasma NT-proBNP levels associated with cardiac structural abnormalities in asymptomatic health examinees with preserved ejection fraction: a retrospective cross-sectional study.

BMJ Open 2019 04 20;9(4):e026030. Epub 2019 Apr 20.

MEDIcheck LAB, Korea Association of Health Promotion, Cheongju, South Korea.

Objectives: Stage B heart failure (HF) is defined as an asymptomatic abnormality of the heart structure or function. The circulating level of N-terminal pro-B-type natriuretic peptide (NT-proBNP) is elevated in symptomatic patients with left ventricular (LV) dysfunction caused by a structural or functional abnormality. This study investigated the association of the NT-proBNP level with echocardiography-detected cardiac structural or diastolic abnormalities in asymptomatic subjects with preserved LV systolic function (ejection fraction >50%).

Methods: We retrospectively studied 652 health examinees who underwent echocardiography and an NT-proBNP test at a health-promotion centre in Seoul, between January 2016 and September 2018. The left ventricular mass index (LVMI) and the left atrial dimension (LAD) were used as markers for structural abnormalities, and the mean e' velocity and mitral early flow velocity/early diastolic tissue velocity (E/e') ratio were used as markers for diastolic dysfunction. The plasma NT-proBNP level was measured using electrochemiluminescence immunoassay (DPC Immulite 2000 XPi, Siemens Healthcare Diagnostics, Tarrytown, New York, USA).

Results: Subjects with preclinical structural abnormalities were older and had a higher body mass index (BMI), higher blood pressure, lower high-density lipoprotein cholesterol level, higher NT-proBNP level, and higher E/e' (p<0.05). Multivariate regression analysis indicated that the factors associated with a higher NT-proBNP level were older age, female sex, lower BMI, higher creatinine level, higher LVMI and higher LAD (p<0.01).

Conclusion: Diastolic dysfunction is not associated with higher NT-proBNP levels, whereas preclinical cardiac structural abnormalities, as well as older age, female sex, lower BMI, and higher creatinine level, are associated with higher NT-proBNP levels.
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http://dx.doi.org/10.1136/bmjopen-2018-026030DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6500281PMC
April 2019

Complete Blood Count Reference Intervals and Patterns of Changes Across Pediatric, Adult, and Geriatric Ages in Korea.

Ann Lab Med 2018 Nov;38(6):503-511

MEDIcheck LAB, Korea Association of Health Promotion, Cheongju, Korea.

Background: Sampling a healthy reference population to generate reference intervals (RIs) for complete blood count (CBC) parameters is not common for pediatric and geriatric ages. We established age- and sex-specific RIs for CBC parameters across pediatric, adult, and geriatric ages using secondary data, evaluating patterns of changes in CBC parameters.

Methods: The reference population comprised 804,623 health examinees (66,611 aged 3-17 years; 564,280 aged 18-59 years; 173,732 aged 60-99 years), and, we excluded 22,766 examinees after outlier testing. The CBC parameters (red blood cell [RBC], white blood cell [WBC], and platelet parameters) from 781,857 examinees were studied. We determined statistically significant partitions of age and sex, and calculated RIs according to the CLSI C28-A3 guidelines.

Results: RBC parameters increased with age until adulthood and decreased with age in males, but increased before puberty and then decreased with age in females. WBC and platelet counts were the highest in early childhood and decreased with age. Sex differences in each age group were noted: WBC count was higher in males than in females during adulthood, but platelet count was higher in females than in males from puberty onwards (P<0.001). Neutrophil count was the lowest in early childhood and increased with age. Lymphocyte count decreased with age after peaking in early childhood. Eosinophil count was the highest in childhood and higher in males than in females. Monocyte count was higher in males than in females (P<0.001).

Conclusions: We provide comprehensive age- and sex-specific RIs for CBC parameters, which show dynamic changes with both age and sex.
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http://dx.doi.org/10.3343/alm.2018.38.6.503DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6056383PMC
November 2018

Evaluation of the LC-1000 Flow Cytometry Screening System for Cervical Cancer Screening in Routine Health Checkups.

Acta Cytol 2018 29;62(4):279-287. Epub 2018 May 29.

MEDIcheck LAB, Korea Association of Health Promotion, Cheongju, Republic of Korea.

Objective: This study evaluated the performance of a flow cytometry system (LC-1000) in screening cervical precancerous lesions at routine health checkups.

Study Design: In total, 928 health examinees were enrolled at 16 health promotion centers in 13 Korean cities between 2016 and 2017. All participants underwent liquid-based cervical cytology and flow cytometry testing to determine the cell proliferation index (CPIx).

Results: The positivity rate of the LC-1000 system increased with the severity of the cervical cytology findings (p for trend < 0.001). When low-grade squamous intraepithelial lesion (LSIL) or higher (including LSIL, high-grade squamous intraepithelial lesion [HSIL], and atypical squamous cells without excluding HSIL [ASC-H]) was defined as gold-standard positivity, the sensitivity, specificity, PPV, and NPV of LC-1000 were 75.3% (95% confidence interval [CI], 66.8-83.7), 58.5% (95% CI, 55.2-61.9), 18.1% (95% CI, 14.5-21.8), and 95.1% [95% CI, 93.2-97.0], respectively. The median CPIx increased significantly from normal cytology to HSIL (p < 0.001). The median CPIx was higher in high-risk human papillomavirus (HR-HPV)-positive cases than in HR-HPV-negative cases (0.23 vs. 0.17, p < 0.001), while it did not differ between HR-HPV-positive and HR-HPV-negative cases with normal cytology findings (0.16 vs. 0.16, p = 0.700).

Conclusion: The LC-1000 system is potentially useful for screening cervical precancer and cancer, especially when excluding normal or ASC of undetermined significance cases in routinely screened populations.
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http://dx.doi.org/10.1159/000489079DOI Listing
August 2018

Comparison of Traditional and Reverse Syphilis Screening Algorithms in Medical Health Checkups.

Ann Lab Med 2017 Nov;37(6):511-515

Institute of Parasitic Diseases, Korea Association of Health Promotion, Seoul, Korea.

Background: The syphilis diagnostic algorithms applied in different countries vary significantly depending on the local syphilis epidemiology and other considerations, including the expected workload, the need for automation in the laboratory and budget factors. This study was performed to investigate the efficacy of traditional and reverse syphilis diagnostic algorithms during general health checkups.

Methods: In total, 1,000 blood specimens were obtained from 908 men and 92 women during their regular health checkups. Traditional screening and reverse screening were applied to the same specimens using automatic rapid plasma regain (RPR) and Treponema pallidum latex agglutination (TPLA) tests, respectively. Specimens that were reverse algorithm (TPLA) reactive, were subjected to a second treponemal test performed by using the chemiluminescent microparticle immunoassay (CMIA).

Results: Of the 1,000 specimens tested, 68 (6.8%) were reactive by reverse screening (TPLA) compared with 11 (1.1%) by traditional screening (RPR). The traditional algorithm failed to detect 48 specimens [TPLA(+)/RPR(-)/CMIA(+)]. The median TPLA cutoff index (COI) was higher in CMIA-reactive cases than in CMIA-nonreactive cases (90.5 vs 12.5 U).

Conclusions: The reverse screening algorithm could detect the subjects with possible latent syphilis who were not detected by the traditional algorithm. Those individuals could be provided with opportunities for evaluating syphilis during their health checkups. The COI values of the initial TPLA test may be helpful in excluding false-positive TPLA test results in the reverse algorithm.
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http://dx.doi.org/10.3343/alm.2017.37.6.511DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5587824PMC
November 2017

Human Papillomavirus Genotype Distribution Among 18,815 Women in 13 Korean Cities and Relationship With Cervical Cytology Findings.

Ann Lab Med 2017 Sep;37(5):426-433

MEDIcheck LAB, Korea Association of Health Promotion, Cheongju, Korea.

Background: The prevalence and genotype distribution of Human papillomavirus (HPV) infection vary depending on geographical region and the immunity provided by vaccines. This study aimed to clarify the recent prevalence and genotype distribution of HPV according to age and cervical cytology findings in Korea.

Methods: This study included 18,815 health examinees that underwent cervical cytology and HPV genotyping tests at 16 centers of Korean Association of Health Promotion in 13 cities in Korea, between January 2014 and October 2015. HPV was genotyped by using multiplex PCR (Anyplex II HPV 28, Seegene, Korea), which detects 19 high-risk HPVs (HR-HPV) and nine low-risk HPVs (LR-HPV).

Results: Overall HPV prevalence was 27.8%, with 22.2% HR-HPV and 11.4% LR-HPV. The five most common carcinogens were HPV 52 (3.2%), 58 (2.7%), 16 (2.0%), 56 (1.9%), and 51 (1.8%). The five most common HR-HPVs in normal cytology samples were HPV 53, 68, 70, 52, and 58, while HPV 16, 52, 58, 33, and 31 were prevalent in high grade squamous intraepithelial lesions (HSIL). In atypical squamous cells of undetermined significance (ASCUS), the prevalence of HR-HPV varied with age; it was highest in those aged <30 yr, declining to a minimum at age 50-59 yr, and then increasing in older women (P<0.05).

Conclusions: The prevalence and distribution of HR-HPV varied with age and cervical cytology findings. This information would be helpful in the development of cervical cancer prevention policies.
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http://dx.doi.org/10.3343/alm.2017.37.5.426DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5500742PMC
September 2017

Comparison of Urine Albumin-to-Creatinine Ratio (ACR) Between ACR Strip Test and Quantitative Test in Prediabetes and Diabetes.

Ann Lab Med 2017 Jan;37(1):28-33

MEDIcheck LAB, Korea Association of Health Promotion, Cheongju, Korea.

Background: Albuminuria is generally known as a sensitive marker of renal and cardiovascular dysfunction. It can be used to help predict the occurrence of nephropathy and cardiovascular disorders in diabetes. Individuals with prediabetes have a tendency to develop macrovascular and microvascular pathology, resulting in an increased risk of retinopathy, cardiovascular diseases, and chronic renal diseases. We evaluated the clinical value of a strip test for measuring the urinary albumin-to-creatinine ratio (ACR) in prediabetes and diabetes.

Methods: Spot urine samples were obtained from 226 prediabetic and 275 diabetic subjects during regular health checkups. Urinary ACR was measured by using strip and laboratory quantitative tests.

Results: The positive rates of albuminuria measured by using the ACR strip test were 15.5% (microalbuminuria, 14.6%; macroalbuminuria, 0.9%) and 30.5% (microalbuminuria, 25.1%; macroalbuminuria, 5.5%) in prediabetes and diabetes, respectively. In the prediabetic population, the sensitivity, specificity, positive predictive value, negative predictive value, and overall accuracy of the ACR strip method were 92.0%, 94.0%, 65.7%, 99.0%, and 93.8%, respectively; the corresponding values in the diabetic population were 80.0%, 91.6%, 81.0%, 91.1%, and 88.0%, respectively. The median [interquartile range] ACR values in the strip tests for measurement ranges of <30, 30-300, and >300 mg/g were 9.4 [6.3-15.4], 46.9 [26.5-87.7], and 368.8 [296.2-575.2] mg/g, respectively, using the laboratory method.

Conclusions: The ACR strip test showed high sensitivity, specificity, and negative predictive value, suggesting that the test can be used to screen for albuminuria in cases of prediabetes and diabetes.
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http://dx.doi.org/10.3343/alm.2017.37.1.28DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5107614PMC
January 2017

Comparing Results of Five Glomerular Filtration Rate-Estimating Equations in the Korean General Population: MDRD Study, Revised Lund-Malmö, and Three CKD-EPI Equations.

Ann Lab Med 2016 Nov;36(6):521-8

Department of Medical Sciences and Translational Medicine, University of Rome Sapienza, Sant'Andrea Hospital, Rome, Italy.

Background: Estimated glomerular filtration rate (eGFR) is a widely used index of kidney function. Recently, new formulas such as the Chronic Kidney Disease Epidemiology Collaboration (CKD-EPI) equations or the Lund-Malmö equation were introduced for assessing eGFR. We compared them with the Modification of Diet in Renal Disease (MDRD) Study equation in the Korean adult population.

Methods: The study population comprised 1,482 individuals (median age 51 [42-59] yr, 48.9% males) who received annual physical check-ups during the year 2014. Serum creatinine (Cr) and cystatin C (CysC) were measured. We conducted a retrospective analysis using five GFR estimating equations (MDRD Study, revised Lund-Malmö, and Cr and/or CysC-based CKD-EPI equations). Reduced GFR was defined as eGFR <60 mL/min/1.73 m².

Results: For the GFR category distribution, large discrepancies were observed depending on the equation used; category G1 (≥90 mL/min/1.73 m²) ranged from 7.4-81.8%. Compared with the MDRD Study equation, the other four equations overestimated GFR, and CysC-based equations showed a greater difference (-31.3 for CKD-EPI(CysC) and -20.5 for CKD-EPI(Cr-CysC)). CysC-based equations decreased the prevalence of reduced GFR by one third (9.4% in the MDRD Study and 2.4% in CKD-EPI(CysC)).

Conclusions: Our data shows that there are remarkable differences in eGFR assessment in the Korean population depending on the equation used, especially in normal or mildly decreased categories. Further prospective studies are necessary in various clinical settings.
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http://dx.doi.org/10.3343/alm.2016.36.6.521DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5011104PMC
November 2016

A novel quantitative evaluation method for quality control results.

Clin Chim Acta 2015 Dec 28;451(Pt B):175-9. Epub 2015 Sep 28.

Korea Association of Health Promotion, Seoul, South Korea.

Background: Quality control (QC) procedures using stable control materials are important for preventing systematic errors (SEs). While the current QC methods assess QC results semi-quantitatively, we designed a novel quantitative QC procedure (QQCP).

Methods: QC results were expressed as Z-scores to analyze results quantitatively. The decision values were accumulated up to 30, with three decision values per run, and were compared to rejection criteria at each run. The probability for false rejection (Pfr) and error detection (Ped) for the QQCP and Westgard multirule methods were estimated using simulated QC data with SEs ranging from 0 to 3 standard deviations (SDs).

Results: The Pfr of the QQCP was 3.4% at the 10th run. When 2 QC materials with the same SEs (0.5 SD and 1.0 SD) were used, the Peds were 36.1% and 95.7% at run 10, respectively. When the SE of each material was greater than 1.5 SDs, the Ped reached 100% at run 10. The QQCP could detect more than 99% of errors in the 6th, 4th, 3rd, and 2nd runs for 2 QC results with 1.5, 2.0, 2.5, and 3.0 SD SEs, respectively.

Conclusion: The QQCP exhibited a Ped value up to 3.3-fold higher than the Westgard method. Implementation of the QQCP would satisfy the high quality goals derived from biological variations.
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http://dx.doi.org/10.1016/j.cca.2015.09.026DOI Listing
December 2015

Reduction of urogenital schistosomiasis with an integrated control project in Sudan.

PLoS Negl Trop Dis 2015 Jan 8;9(1):e3423. Epub 2015 Jan 8.

Department of Parasitology and Tropical Medicine, Seoul National University College of Medicine, Seoul, Korea.

Purpose: Schistosomiasis remains a major public health concern in Sudan, particularly Schistosoma haematobium infection. This study presents the disease-reduction outcomes of an integrated control program for schistosomiasis in Al Jabalain locality of White Nile State, Sudan from 2009 through 2011.

Methods: The total population of the project sites was 482,902, and the major target group for intervention among them was 78,615 primary school students. For the cross-sectional study of the prevalence, urine and stool specimens were examined using the urine sedimentation method and the Kato cellophane thick smear method, respectively. To assess the impacts of health education for students and a drinking water supply facility at Al Hidaib village, questionnaire survey was done.

Results: The overall prevalence for S. haematobium and S. mansoni at baseline was 28.5% and 0.4%, respectively. At follow-up survey after 6-9 months post-treatment, the prevalence of S. haematobium infection was reduced to 13.5% (95% CI = 0.331-0.462). A higher reduction in prevalence was observed among girls, those with moderately infected status (around 20%), and residents in rural areas, than among boys, those with high prevalence (>40%), and residents in urban areas. After health education, increased awareness about schistosomiasis was checked by questionnaire survey. Also, a drinking water facility was constructed at Al Hidaib village, where infection rate was reduced more compared to that in a neighboring village within the same unit. However, we found no significant change in the prevalence of S. mansoni infection between baseline and follow-up survey (95% CI = 0.933-6.891).

Conclusions: At the end of the project, the prevalence of S. haematobium infection was reduced by more than 50% in comparison with the baseline rate. Approximately 200,000 subjects had received either praziquantel therapy, health education, or supply of clean water. To consolidate the achievements of this project, the integrated intervention should be adapted continuously.
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http://dx.doi.org/10.1371/journal.pntd.0003423DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4288734PMC
January 2015

Reduction of urogenital schistosomiasis with an integrated control project in Sudan.

PLoS Negl Trop Dis 2015 Jan 8;9(1):e3423. Epub 2015 Jan 8.

Department of Parasitology and Tropical Medicine, Seoul National University College of Medicine, Seoul, Korea.

Purpose: Schistosomiasis remains a major public health concern in Sudan, particularly Schistosoma haematobium infection. This study presents the disease-reduction outcomes of an integrated control program for schistosomiasis in Al Jabalain locality of White Nile State, Sudan from 2009 through 2011.

Methods: The total population of the project sites was 482,902, and the major target group for intervention among them was 78,615 primary school students. For the cross-sectional study of the prevalence, urine and stool specimens were examined using the urine sedimentation method and the Kato cellophane thick smear method, respectively. To assess the impacts of health education for students and a drinking water supply facility at Al Hidaib village, questionnaire survey was done.

Results: The overall prevalence for S. haematobium and S. mansoni at baseline was 28.5% and 0.4%, respectively. At follow-up survey after 6-9 months post-treatment, the prevalence of S. haematobium infection was reduced to 13.5% (95% CI = 0.331-0.462). A higher reduction in prevalence was observed among girls, those with moderately infected status (around 20%), and residents in rural areas, than among boys, those with high prevalence (>40%), and residents in urban areas. After health education, increased awareness about schistosomiasis was checked by questionnaire survey. Also, a drinking water facility was constructed at Al Hidaib village, where infection rate was reduced more compared to that in a neighboring village within the same unit. However, we found no significant change in the prevalence of S. mansoni infection between baseline and follow-up survey (95% CI = 0.933-6.891).

Conclusions: At the end of the project, the prevalence of S. haematobium infection was reduced by more than 50% in comparison with the baseline rate. Approximately 200,000 subjects had received either praziquantel therapy, health education, or supply of clean water. To consolidate the achievements of this project, the integrated intervention should be adapted continuously.
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http://dx.doi.org/10.1371/journal.pntd.0003423DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4288734PMC
January 2015

Prevalence, risk factors, and clinical manifestations of schistosomiasis among school children in the White Nile River basin, Sudan.

Parasit Vectors 2014 Oct 15;7:478. Epub 2014 Oct 15.

Departments of Infection Biology, Chungnam National University School of Medicine, Daejeon, 301-131, Korea.

Background: We investigated the prevalence, risk factors, and clinical manifestations of schistosomiasis in White Nile State, Sudan, to determine the local characteristics of schistosomiasis in the White Nile River basin.

Methods: Urine and stool samples were collected from 338 students (176 boys, 162 girls) at three primary schools and were examined using the urine filtration method and the Kato-Katz technique, respectively. Of the students, 200 were interviewed using a semi-structured questionnaire to assess water-contact patterns and health conditions related with urinary schistosomiasis.

Results: Of the 338 students, egg-positive rates for S. haematobium and S. mansoni were 45.0% and 5.9%, respectively, and 4.4% were mixed. The intensities of S. haematobium and S. mansoni infection were 1.091 ± 0.744 log EP10 (eggs per 10 mL of urine, mean ± SD = 57 ± 172 EP10) and 1.787 ± 0.844 log EPG (eggs per gram of stool, mean ± SD = 156 ± 176 EPG), respectively. The prevalence and intensity of S. haematobium infection differed significantly among the three schools, but not by gender or age. Urinary schistosomiasis was significantly associated with the frequencies of contaminated water contact, taking baths, swimming, and wading the stream; however, frequencies of these events were not significantly correlated with infection intensity. Self-reported hematuria and dysuria also correlated significantly with urinary schistosomiasis.

Conclusions: The overall prevalence of schistosomiasis, especially urinary schistosomiasis, is high in the White Nile River basin, Sudan, and is closely associated with frequencies of water contact, taking baths, swimming, and wading the stream. We strongly recommend implementation of an integrated schistosomiasis control program in this area.
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http://dx.doi.org/10.1186/s13071-014-0478-6DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4200116PMC
October 2014

Evaluation of circumsporozoite protein of Plasmodium vivax to estimate its prevalence in the Republic of Korea: an observational study of incidence.

Malar J 2013 Dec 13;12:448. Epub 2013 Dec 13.

Departments of Parasitology, Inha University School of Medicine, Incheon 400-712, Republic of Korea.

Background: Plasmodium vivax re-emerged in 1993. Although the number of infections has been steadily decreasing, it is likely to continue to affect public health until it is eradicated. The aim of this study is to measure anti-circumsporozoite protein (CSP) antibody and compare malaria prevalence. As to understand the prevalence, an epidemiology study has to be conducted in the Republic of Korea.

Methods: A total of 1,825 and 1,959 blood samples were collected in 2010 and 2011, respectively, from the inhabitants of Ganghwa and Cheorwon counties. The antibody titers of the inhabitants were measured by enzyme-linked immunosorbent assay (ELISA) using recombinant protein purified from Escherichia coli transformed with a CSP gene-inserted pET-28a(+) expression vector. Microscopic examination was performed to identify malaria parasites.

Results: The annual parasite incidence (API) in Ganghwa decreased from 4.28 in 2010 to 2.23 in 2011, and that in Cheorwon decreased from 1.88 in 2010 to 1.15 in 2011. The antibody-positive CSP rate in these areas also decreased from 18.14% (331/1825) in 2010 to 15.36% (301/1959) in 2011. Pearson analysis showed a strong correlation between the API and the antibody-positive CSP rate in these areas (r = 1.000, P < 0.01). The intensity of the immune responses of the inhabitants of Cheorwon, as measured by the mean optical density, decreased from 0.9186 ± 0.0472 in 2010 to 0.7035 ± 0.0457 in 2011 (P = 0.034), but increased in Ganghwa from 0.7649 ± 0.0192 in 2010 to 0.8237 ± 0.1970 in 2011 (P = 0.006). The immune response increased according to age (r = 0.686, P = 0.041).

Conclusions: The positive CSP-ELISA rate was closely related to the API in the study areas. This suggests that seroepidemiological studies based on CSP-ELISA may be helpful in estimating the malaria prevalence. Moreover, such studies can be used to establish and evaluate malaria control and eradication programmes in high-risk areas in Korea.
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http://dx.doi.org/10.1186/1475-2875-12-448DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3878750PMC
December 2013

Serologic survey of toxoplasmosis in Seoul and Jeju-do, and a brief review of its seroprevalence in Korea.

Korean J Parasitol 2012 Dec 26;50(4):287-93. Epub 2012 Nov 26.

Department of Parasitology and Tropical Medicine, Seoul National University College of Medicine, Seoul 110-799, Korea.

Knowledge of the prevalence of human Toxoplasma gondii infection is required in the Republic of Korea. In this study, we surveyed the seroprevalence of T. gondii infection and analyzed the risk factors associated with seropositivity among residents in 2 administrative districts; Seoul and the island of Jeju-do, which have contrasting epidemiologic characteristics. Sera and blood collected from 2,150 residents (1,114 in Seoul and 1,036 in Jeju-do) were checked for IgG antibody titers using ELISA and for the T. gondii B1 gene using PCR. In addition, participants completed a questionnaire that solicited information on gender, age, occupation, eating habits, history of contact with animals, and travel abroad. The T. gondii B1 gene was not detected in all residents examined. However, ELISA showed 8.0% (89 of 1,114 sera) positive for IgG antibodies against T. gondii in Seoul and 11.3% (117 of 1,036 sera) in Jeju-do. In both districts, the positive rates were higher in males than in females, and those 40-79 years of age showed higher rates than other ages. In Seoul, residents older than 70 years of age showed the highest positive rate, 14.9%, whereas in Jeju-do the highest prevalence, 15.6%, was in those in their sixties. The higher seropositive rate in Jeju-do than in Seoul may be related to eating habits and occupations. The present results and a review of related literature are indicative of an increased seroprevalence of T. gondii in Korea in recent years.
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http://dx.doi.org/10.3347/kjp.2012.50.4.287DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3514419PMC
December 2012

Heterogeneity in obesity status and cardiovascular risks in multiethnic Asian female immigrants in South Korea.

Asia Pac J Public Health 2015 Mar 20;27(2):NP448-56. Epub 2012 Sep 20.

Korea Association of Health Promotion, Seoul, Korea.

The present study investigated the prevalence of obesity and the associated health conditions of multiethnic Asian female immigrants in Korea. Data were collected from 2246 immigrant wives in 7 largest ethnic groups in a national health examination program. The mean body mass index was 21.9 ± 3.3 kg/m(2). Prevalence of obesity (body mass index ≥25 kg/m(2)) among immigrant women was 15.4%. Age-adjusted prevalence of obesity varied among groups by native country (from 10.4% for Japanese to 36.3% for Thai women). The likelihood of obesity significantly increased with years of residence in Korea (odds ratio [OR] = 1.44 for 5.0-9.9 years; 1.85 for ≥10 years), physical inactivity (OR = 1.84), and eating spicy and/or salty food (OR = 1.45). Prevalence of chronic health conditions also differed by country of origin. Significant associations were observed between obesity and elevated blood pressure (OR = 1.87), obesity and elevated cholesterol level (OR = 2.83), and obesity and prediabetes/diabetes (OR = 2.44) after adjusting for age, country of origin, and years of residence in Korea.
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http://dx.doi.org/10.1177/1010539512459751DOI Listing
March 2015

Improvements in the metabolic syndrome and stages of change for lifestyle behaviors in korean older adults.

Osong Public Health Res Perspect 2012 Jun;3(2):85-93

Seoul National University, Graduate School of Public Health & Center for Health Promotion Research, Seoul, Korea.

Objectives: This study aims to examine the effectiveness of a 6-month lifestyle modification program on the improvement in metabolic syndrome (MetS) status and in stages of change for lifestyle behaviors associated with MetS among Korean older adults.

Methods: A lifestyle modification program was developed based on the transtheoretical model. The program consisted of health counseling, education classes, a self-management handbook, newsletters and a health diary. Older adults aged ≥60 (n = 480) with MetS were randomly assigned to the intervention group (IG) or the comparison group (CG). The IG received a comprehensive 6-month lifestyle modification intervention, while the CG received minimal information on MetS and lifestyle modification. Health examination and selfadministered survey were conducted before and after the intervention to determine the effectiveness of the program.

Results: After the intervention, the prevalence of MetS decreased to 38.1% in the IG and 52.4% in the CG (p = 0.046). The IG improved abdominal obesity (p = 0.016), blood pressure (p = 0.030), and triglyceride (p = 0.005) more than the CG did. The IG demonstrated significant improvements in the behavioral stages for portion control (p = 0.021), balanced diet (p < 0.001) and adequate intake of fruits and vegetables (p = 0.012). The IG reduced the prevalence of abdominal obesity (OR = 2.34) and improved MetS status (OR = 1.79) better than the CG. The IG were more likely to advance from preaction stages at baseline to action stage at post-intervention for portion control (OR = 3.29) and adequate intake of fruits and vegetables (OR = 2.06).

Conclusion: Lifestyle modification can improve the MetS status and behavioral stages in older adults.
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http://dx.doi.org/10.1016/j.phrp.2012.04.007DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3747641PMC
June 2012

Prevalence of monoclonal gammopathy of undetermined significance in an elderly urban Korean population.

Am J Hematol 2011 Sep 22;86(9):752-5. Epub 2011 Jul 22.

Department of Laboratory Medicine, Seoul Clinical Laboratories, Seoul Medical Science Institute, Seoul, Republic of Korea.

Research on the epidemiology of monoclonal gammopathy of undetermined significance (MGUS) is limited in Korea. The aim of this study was to determine the prevalence and characteristics of MGUS in an elderly urban Korean population. A random sample of 1118 Korean elders was selected from residents aged 65 years or older living in Seongnam, Korea 1 year from August 2005. We obtained plasma samples remaining after scheduled tests for the Korean Longitudinal Study on Health and Aging. The mean age of the study population was 72 years (range, 65-97 years). To screen for MGUS, immunofixation and free light-chain (FLC) assays were performed. Age-adjusted and gender-adjusted MGUS prevalence rates in 680 responders were estimated as 3.3% [95% confidence interval (CI) = 2.0-4.6%], and the estimated age-adjusted prevalence of MGUS was 4.3% in men (95% CI = 1.9-6.6%) and 2.6% in women (95% CI = 1.0-4.2%). Abnormal FLC ratios were detected in 10% of MGUS cases. Multivariate analysis of 945 participants revealed that significant risk factors for MGUS included advanced age, male sex, hyperproteinemia, increased erythrocyte sedimentation rate, and abnormal FLC ratio. MGUS is less prevalent among elderly Koreans (3.3%) than other races. This is the first study to estimate the prevalence of MGUS in the Korean elderly population. Our findings should be confirmed with additional studies analyzing follow-up samples from 2010.
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http://dx.doi.org/10.1002/ajh.22095DOI Listing
September 2011

Mutation analysis of the APC gene in unrelated Korean patients with FAP: four novel mutations with unusual phenotype.

Fam Cancer 2011 Mar;10(1):21-6

Division of Molecular Genetics, Department of Laboratory Medicine, Seoul Clinical Laboratories, Seoul Medical Science Institute, Yongsan-gu, Seoul, Korea.

Germline mutations within the adenomatous polyposis coli (APC) gene are responsible for most cases of familial adenomatous polyposis (FAP), an autosomal dominantly inherited predisposition to colorectal cancer. To date more than 900 different APC germline mutations have been characterized worldwide demonstrating allelic heterogeneity. Here, we analyzed the APC gene in 23 DNA samples from unrelated Korean patients with the typical clinical symptoms of FAP by denaturing high-performance liquid chromatography (DHPLC) and direct sequencing. We identified 20 different APC sequence variants, including 9 truncating mutations, 1 missense mutation, 7 polymorphisms, and 3 intronic variants. Nine different truncating mutations, including four novel mutations (p.Leu180TyrfsX5, p.Gly567X, p.Ser1275PhefsX13, p.Leu1280CysfsX8), were detected. The most common mutation was a 5 bp deletion at codon 1,309 (p.Glu1309AspfsX4) as in Western studies. The next most common mutation was p.Ser1275PhefsX13 with a severe form of FAP with many extracolonic manifestations; this was a novel mutation identified in our study and may represent the second hot-spot mutation in a Korean population. Novel mutations are of particular interest because of the unusual phenotypic features shown by patients. In present study, we found new positions associated with thyroid cancer (codon 180) and desmoid tumor (codon 1,280), which have not been previously reported. The results of this molecular study have revealed the existence of novel pathogenic mutations in Korean patients with FAP. In addition to allowing phenotype-genotype correlations to be performed, these results are currently being used in genetic counseling and in patient care.
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http://dx.doi.org/10.1007/s10689-010-9363-4DOI Listing
March 2011

Molecular identification of the novel Gγ-β hybrid hemoglobin: Hb Gγ-β Ulsan (Gγ through 13; β from 19).

Blood Cells Mol Dis 2010 Dec 29;45(4):276-9. Epub 2010 Oct 29.

Department of Laboratory Medicine, Seoul National University Hospital, 110-744, Seoul, Republic of Korea.

Gene fusion is a very rare mechanism that produces hemoglobin variants. Less than ten types of β-like hybrid globins have been reported to date. Herein we identified the first hybrid hemoglobin between Gγ- and β-globins in a five-year-old Korean male who had thalassemia minor feature and triplication of the HBA2 gene (αα/αααα). The novel globin originated from a 27,707-base pair deletion spanning from the HBG2 to HBB gene (NG_000007.3:g.42947_70653del). Its protein sequence included 13 N-terminal amino acids from Gγ-globin, five common amino acids from Gγ- and β-globins, and 128 amino acids from β-globin (Gγ through 13; β from 19). Molecular genetic analyses characterized the hybrid DNA and RNA. Mass spectrometry and de novo protein sequencing successfully identified the fusion peptide in the hybrid hemoglobin. We named this novel hybrid Hb Gγ-β Ulsan. The novel hemoglobin constituted 37.0% of the total hemoglobin and showed reduced oxygen affinity.
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http://dx.doi.org/10.1016/j.bcmd.2010.10.001DOI Listing
December 2010

Concurrent p16 methylation pattern as an adverse prognostic factor in multiple myeloma: a methylation-specific polymerase chain reaction study using two different primer sets.

Ann Hematol 2011 Jan 19;90(1):73-9. Epub 2010 Aug 19.

Department of Laboratory Medicine, Chosun University College of Medicine, Gwangju, South Korea.

Disruption of cell cycle control genes, including p16, is known to contribute to the cancerogenesis of multiple myeloma (MM). We investigated the methylation status of p16 and its association with common cytogenetic changes, clinicolaboratory findings, and survival in MM. Methylation-specific polymerase chain reaction was performed in 99 newly diagnosed MM patients using two different sets of primers (p16M1 and p16M2). Four patterns of p16 promoter methylation were observed: (1) concurrent methylation of p16M1 and p16M2 (P1P2), 27.3%; (2) methylation of p16M1 alone (P1N2), 7.1%; (3) methylation of p16M2 alone (N1P2), 26.3%; and (4) no methylation (N1N2), 39.4%. Patients with p16P1P1 showed shorter survivals than those with the other methylation patterns (P1N2, N1P2, or N1N2; median survival, 12 vs. 43 months; P < 0.001), regardless of the treatment protocol. In a multivariate analysis, p16P1P2 was an independent prognostic factor of adverse outcome in MM. According to International Staging System (ISS), the study population could be divided into 21.2% (20/94) for stage I, 22.3% (21/94) for stage II, and 56.4% (53/94) for stage III (P = 0.003). ISS can divide patients into prognostic groups. Of note, in patients older than 60 years, ISS was not reflective of disease stage (P = 0.114). If p16P1P2 sets up as stage 4 of ISS, modified ISS could be a more reliable staging system irrespective of age in Korean MM patients (P = 0.003 and P = 0.004 in patients younger than 60 years and in patients older than 60 years, respectively). Our study suggests the potential use of p16 methylation status in predicting the outcome of MM patients and the applicability of demethylating agents in MM.
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http://dx.doi.org/10.1007/s00277-010-1043-9DOI Listing
January 2011

[A case of post-essential thrombocythemia myelofibrosis with severe osteosclerosis].

Korean J Lab Med 2010 Apr;30(2):122-5

Department of Laboratory Medicine, Dongguk University Ilsan Hospital, Goyang, Korea.

Essential thrombocythemia (ET) is a chronic myeloproliferative neoplasm that involves primarily the megakaryocytic lineage. After many years, a few patients with ET may develop bone marrow (BM) fibrosis and rarely develop osteosclerosis. A 60-yr-old female was admitted due to severe left upper quadrant abdominal discomfort. She had been diagnosed as ET 19 yrs ago. On liver computed tomography severe splenomegaly was shown. Laboratory tests revealed WBC 24.3x10(9)/L, hemoglobin 13.4 g/dL, platelets 432x10(9)/L, lactate dehydrogenase 4,065 IU/L (reference range; 240-480). Blood smear demonstrated leukoerythroblastosis, teardrop cells, and giant and hypogranular platelets. BM study revealed inadequate aspirate due to dry tap. BM biopsy showed clusters of dysplastic megakaryocytes, grade 3 fibrosis, and severe osteosclerosis. Major/minor BCR-ABL1 rearrangement and JAK2 V617F mutation were not detected. Cytogenetic studies revealed normal karyotype. According to the 2008 WHO diagnostic criteria, the patient was diagnosed as having post-essential thrombocythemia myelofibrosis with severe osteosclerosis.
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http://dx.doi.org/10.3343/kjlm.2010.30.2.122DOI Listing
April 2010
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