Publications by authors named "Mustafa Tosur"

20 Publications

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Sex differences in circulating leptin as a marker of adiposity in obese or overweight adolescents with type 1 diabetes.

BMJ Open Diabetes Res Care 2020 10;8(1)

Children's Nutrition Research Center, Department of Pediatrics, Baylor College of Medicine, Houston, Texas, USA.

Introduction: We aimed to test whether the serum adipokines leptin and adiponectin are more strongly associated with body fat percentage (BF%) than body mass index (BMI) in adolescents with type 1 diabetes (T1D) and overweight/obesity.

Research Design And Methods: We studied all participants in the T1D Exchange Metformin Study (n=122, median age 12.9 years, range 12-19.5; 32% males; 77% non-Hispanic whites, 100% overweight or obesity; median diabetes duration 6.7 years, range 1.4-15) with a baseline serum sample where we measured leptin and adiponectin concentrations. Anthropometric, clinical, laboratory and dual-energy X-ray absorptiometry (DEXA) scan measurements were analyzed. We compared correlation coefficients between variables of interest.

Results: BF% by DEXA was significantly correlated with BMI Z-score (r=0.38, p<0.0001), BMI per cent of the 95th percentile (BMI%95) (r=0.45, p<0.0001), waist circumference (r=0.46, p<0.0001), leptin (r=0.58, p<0.00001) and leptin/adiponectin ratio (r=0.36, p<0.0001), while it was not significantly correlated with absolute body weight, adiponectin or insulin dose (total or basal). BF% was significantly more strongly correlated with leptin than with BMI Z-score in the overall group (p=0.022). However, there were sex-based differences. Among the significant correlations in the overall group, BF% was most strongly associated with leptin (r=0.75) in boys (n=39) but with waist circumference (r=0.58) in girls (n=83) (all p<0.0001).

Conclusions: Serum leptin could be used as a surrogate convenient marker of adiposity in overweight/obese adolescent boys with T1D, equivalent to BMI Z-score or BMI%95. In girls, waist circumference was the best performing marker overall, and was also strongly correlated with %BF in boys.
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http://dx.doi.org/10.1136/bmjdrc-2020-001683DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7580039PMC
October 2020

Challenges in the diagnosis of diabetes type in pediatrics.

Pediatr Diabetes 2020 11 23;21(7):1064-1073. Epub 2020 Jul 23.

Diabetes and Endocrinology Section, Baylor College of Medicine, Texas Children's Hospital, Houston, Texas, USA.

The incidence of diabetes, both type 1 and type 2, is increasing. Health outcomes in pediatric diabetes are currently poor, with trends indicating that they are worsening. Minority racial/ethnic groups are disproportionately affected by suboptimal glucose control and have a higher risk of acute and chronic complications of diabetes. Correct clinical management starts with timely and accurate classification of diabetes, but in children this is becoming increasingly challenging due to high prevalence of obesity and shifting demographic composition. The growing obesity epidemic complicates classification by obesity's effects on diabetes. Since the prevalence and clinical characteristics of diabetes vary among racial/ethnic groups, migration between countries leads to changes in the distribution of diabetes types in a certain geographical area, challenging the clinician's ability to classify diabetes. These challenges must be addressed to correctly classify diabetes and establish an appropriate treatment strategy early in the course of disease for all. This may be the first step in improving diabetes outcomes across racial/ethnic groups. This review will discuss the pitfalls in the current diabetes classification scheme that is leading to increasing overlap between diabetes types and heterogeneity within each type. It will also present proposed alternative classification schemes and approaches to understanding diabetes type that may improve the timely and accurate classification of pediatric diabetes type.
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http://dx.doi.org/10.1111/pedi.13070DOI Listing
November 2020

The Effect of Ethnicity in the Rate of Beta-Cell Functional Loss in the First 3 Years After Type 1 Diabetes Diagnosis.

J Clin Endocrinol Metab 2020 12;105(12)

Baylor College of Medicine, Texas Children's Hospital, Houston, Texas.

Objective: We set forth to compare ethnicities for metabolic and immunological characteristics at the clinical diagnosis of type 1 diabetes (T1D) and assess the effect of ethnicity on beta-cell functional loss within 3 years after clinical diagnosis.

Research Methods And Design: We studied participants in TrialNet New Onset Intervention Trials (n = 624, median age = 14.4 years, 58% male, 8.7% Hispanic) and followed them prospectively for 3 years. Mixed meal tolerance tests (MMTT) were performed within 6 months following clinical diagnosis and repeated semiannually. Unless otherwise indicated, analyses were adjusted for age, sex, BMI Z-score, and diabetes duration.

Results: At T1D clinical diagnosis, Hispanics, compared with non-Hispanic whites (NHW), had a higher frequency of diabetic ketoacidosis (DKA) (44.7% vs 25.3%, OR = 2.36, P = 0.01), lower fasting glucose (97 vs 109 mg/dL, P = 0.02) and higher fasting C-peptide (1.23 vs 0.94 ng/mL, P = 0.02) on the first MMTT, and higher frequency of ZnT8 autoantibody positivity (n = 201, 94.1% vs 64%, OR = 7.98, P = 0.05). After exclusion of participants in experimental arms of positive clinical trials, C-peptide area under the curve (AUC) trajectories during the first 3 years after clinical diagnosis were not significantly different between Hispanics and NHW after adjusting for age, sex, BMI-z score, and DKA (n = 413, P = 0.14).

Conclusion: Despite differences in the metabolic and immunological characteristics at clinical diagnosis of T1D between Hispanics and NHW, C-peptide trajectories did not differ significantly in the first 3 years following clinical diagnosis after adjustment for body mass index and other confounders. These findings may inform the design of observational studies and intervention trials in T1D.
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http://dx.doi.org/10.1210/clinem/dgaa348DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7531906PMC
December 2020

Medication-induced hyperglycemia: pediatric perspective.

BMJ Open Diabetes Res Care 2020 01;8(1)

Department of Pediatrics, Section of Diabetes and Endocrinology, Baylor College of Medicine, Houston, Texas, USA.

Medication-induced hyperglycemia is a frequently encountered clinical problem in children. The intent of this review of medications that cause hyperglycemia and their mechanisms of action is to help guide clinicians in prevention, screening and management of pediatric drug-induced hyperglycemia. We conducted a thorough literature review in PubMed and Cochrane libraries from inception to July 2019. Although many pharmacotherapies that have been associated with hyperglycemia in adults are also used in children, pediatric-specific data on medication-induced hyperglycemia are scarce. The mechanisms of hyperglycemia may involve β cell destruction, decreased insulin secretion and/or sensitivity, and excessive glucose influx. While some medications (eg, glucocorticoids, L-asparaginase, tacrolimus) are markedly associated with high risk of hyperglycemia, the association is less clear in others (eg, clonidine, hormonal contraceptives, amiodarone). In addition to the drug and its dose, patient characteristics, such as obesity or family history of diabetes, affect a child's risk of developing hyperglycemia. Identification of pediatric patients with increased risk of developing hyperglycemia, creating strategies for risk reduction, and treating hyperglycemia in a timely manner may improve patient outcomes.
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http://dx.doi.org/10.1136/bmjdrc-2019-000801DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6954773PMC
January 2020

Single Islet Autoantibody at Diagnosis of Clinical Type 1 Diabetes is Associated With Older Age and Insulin Resistance.

J Clin Endocrinol Metab 2020 05;105(5)

University of South Florida, Tampa, Florida.

Context: Multiple islet autoantibody positivity usually precedes clinical (stage 3) type 1 diabetes (T1D).

Objective: To test the hypothesis that individuals who develop stage 3 T1D with only a single autoantibody have unique metabolic differences.

Design: Cross-sectional analysis of participants in the T1D TrialNet study.

Setting: Autoantibody-positive relatives of individuals with stage 3 T1D.

Participants: Autoantibody-positive relatives who developed stage 3 T1D (at median age 12.4 years, range = 1.4-58.6) and had autoantibody data close to clinical diagnosis (n = 786, 47.4% male, 79.9% non-Hispanic white).

Main Outcome Measures: Logistic regression modeling was used to assess relationships between autoantibody status and demographic, clinical, and metabolic characteristics, adjusting for potential confounders and correcting for multiple comparisons.

Results: At diagnosis of stage 3 T1D, single autoantibody positivity, observed in 119 (15.1%) participants (72% GAD65, 13% microinsulin antibody assay, 11% insulinoma-associated antigen 2, 1% islet cell antibody, 3% autoantibodies to zinc transporter 8 [ZnT8]), was significantly associated with older age, higher C-peptide measures (fasting, area under the curve, 2-hour, and early response in oral glucose tolerance test), higher homeostatic model assessment of insulin resistance, and lower T1D Index60 (all P < 0.03). While with adjustment for age, 2-hour C-peptide remained statistically different, controlling for body mass index (BMI) attenuated the differences. Sex, race, ethnicity, human leukocyte antigen DR3-DQ2, and/or DR4-DQ8, BMI category, and glucose measures were not significantly associated with single autoantibody positivity.

Conclusions: Compared with multiple autoantibody positivity, single autoantibody at diagnosis of stage 3 T1D was associated with older age and insulin resistance possibly mediated by elevated BMI, suggesting heterogeneous disease pathogenesis. These differences are potentially relevant for T1D prevention and treatment.
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http://dx.doi.org/10.1210/clinem/dgz296DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7089846PMC
May 2020

Primary hyperparathyroidism versus familial hypocalciuric hypercalcemia: a challenging diagnostic evaluation in an adolescent female.

Ann Pediatr Endocrinol Metab 2019 Sep 30;24(3):195-198. Epub 2019 Sep 30.

Section of Diabetes and Endocrinology, Department of Pediatrics, Texas Children's Hospital, Baylor College of Medicine, Houston, TX, USA.

Primary hyperparathyroidism (PHPT) and familial hypocalciuric hypercalcemia (FHH) have significantly different treatment approaches, so physicians must be careful to differentiate these 2 diseases. Herein, we report a 14-year-old female who presented with symptomatic hypercalcemia (12 mg/dL; reference range, 9.2-10.7 mg/dL), elevated intact parathyroid hormone (iPTH) (236 pg/mL; reference range, 9-69 pg/mL), and vitamin D deficiency (6 ng/mL; reference range, ≥ 20 ng/mL). On numerous occasions, her 24-hour urine calcium was more than 4 mg/kg/day, consistent with PHPT, but her fractional excretion of calcium on 24-hour urine collection was consistently below 1%, in line with FHH. 99mTc-Sestamibi scan failed to detect any abnormalities. However, a 4-dimensional computed tomography scan of the neck revealed a right superior parathyroid adenoma which was excised with a focused parathyroidectomy. Although the patient's calcium and iPTH levels normalized, her nonspecific symptoms persisted. This case illustrates both the challenges of differentiating PHPT from FHH and the limitations of a first-line imaging tool in identifying a parathyroid adenoma.
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http://dx.doi.org/10.6065/apem.2019.24.3.195DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6790872PMC
September 2019

Considerations for total thyroidectomy in an adolescent with mutation.

Ther Adv Endocrinol Metab 2018 Sep 4;9(9):299-301. Epub 2018 Jul 4.

Department of Pediatrics, Baylor College of Medicine, Houston, TX, USA.

Individuals with PTEN Hamartoma Tumor Syndrome (PHTS) are at greatly increased risk for developing well-differentiated thyroid cancer. Specific circumstances in which total thyroidectomies should be considered have not been defined. A 14-year-old macrocephalic female with history of developmental delay and lipoma over her left flank presented with neck swelling and was found have multinodular goiter and auto-immune thyroiditis. Asymptomatic tracheal narrowing was also detected on her initial diagnostic imaging. Later on, she developed positional dyspnea during sleep. Genetic testing revealed a heterozygous pathogenic variant in the gene (c.463T>A). A total thyroidectomy was performed. In addition to addressing the symptomology in our case, a total thyroidectomy also fortuitously eliminated the thyroid cancer risk. This case spurred us on further to identify specific clinical scenarios where total thyroidectomy may be considered as a true prophylactic measure to manage thyroid cancer risk in PHTS patients.
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http://dx.doi.org/10.1177/2042018818784517DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6116769PMC
September 2018

Adjuvant Pharmacotherapies to Insulin for the Treatment of Type 1 Diabetes.

Curr Diab Rep 2018 08 17;18(10):79. Epub 2018 Aug 17.

Section of Diabetes and Endocrinology, Department of Pediatrics, Texas Children's Hospital, Baylor College of Medicine, 6701 Fannin St, Suite 10.20, Houston, TX, 77030, USA.

Purpose Of Review: Insulin therapy alone fails to achieve target glycemic control in the majority of individuals with type 1 diabetes (T1D), motivating the investigation of additive medications. This review focuses on the recent findings on the use of adjunctive pharmacotherapy in T1D.

Recent Findings: Metformin and glucagon-like peptide-1 receptor agonists have been associated with weight reduction and decrease in daily insulin requirements without sustainable improvement in glycemic control. Sodium-glucose cotransporter (SGLT)-2 inhibitors, dual SGLT-1/2 inhibitors, and pramlintide have been shown to reduce hemoglobin A1c, induce weight loss, and lower insulin dose. The benefits of dipeptidyl peptidase-4 inhibitors, thiazolidinediones, and alpha glucosidase inhibitors appear to be more limited. Gastrointestinal symptoms and increased hypoglycemia are adverse effects of certain classes. Although not devoid of side effects, additive pharmacotherapies in T1D can improve glycemic control and lower body weight and insulin requirement. Longer studies are needed before consideration for widespread clinical care.
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http://dx.doi.org/10.1007/s11892-018-1041-1DOI Listing
August 2018

Case 2: 3-month-old Boy with Micropenis.

Pediatr Rev 2018 Jul;39(7):363-365

Department of Pediatrics, Section of Diabetes and Endocrinology, Texas Children's Hospital, Baylor College of Medicine, Houston, TX.

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http://dx.doi.org/10.1542/pir.2017-0067DOI Listing
July 2018

Ethnic differences in progression of islet autoimmunity and type 1 diabetes in relatives at risk.

Diabetologia 2018 09 21;61(9):2043-2053. Epub 2018 Jun 21.

Section of Diabetes and Endocrinology, Department of Pediatrics, Texas Children's Hospital, Baylor College of Medicine, 6701 Fannin St, Suite 10.20, Houston, TX, 77030, USA.

Aims/hypothesis: We hypothesised that progression of islet autoimmunity and type 1 diabetes mellitus differs among races/ethnicities in at-risk individuals.

Methods: In this study, we analysed the data from the Type 1 Diabetes TrialNet Pathway to Prevention Study. We studied 4873 non-diabetic, autoantibody-positive relatives of individuals with type 1 diabetes followed prospectively (11% Hispanic, 80.9% non-Hispanic white [NHW], 2.9% non-Hispanic black [NHB] and 5.2% non-Hispanic other [NHO]). Primary outcomes were time from single autoantibody positivity confirmation to multiple autoantibody positivity, and time from multiple autoantibody positivity to type 1 diabetes mellitus diagnosis.

Results: Conversion from single to multiple autoantibody positivity was less common in Hispanic individuals than in NHW individuals (HR 0.66 [95% CI 0.46, 0.96], p = 0.028) adjusting for autoantibody type, age, sex, Diabetes Prevention Trial Type 1 Risk Score and HLA-DR3-DQ2/DR4-DQ8 genotype. In participants who screened positive for multiple autoantibodies (n = 2834), time to type 1 diabetes did not differ by race/ethnicity overall (p = 0.91). In children who were <12 years old when multiple autoantibody positivity was determined, being overweight/obese had differential effects by ethnicity: type 1 diabetes risk was increased by 36% in NHW children (HR 1.36 [95% CI 1.04, 1.77], p = 0.024) and was nearly quadrupled in Hispanic children (HR 3.8 [95% CI 1.6, 9.1], p = 0.0026). We did not observe this interaction in participants who were ≥12 years old at determination of autoantibody positivity, although this group size was limited. No significant differential risks were observed between individuals of NHB and NHW ethnicity.

Conclusions/interpretation: The risk and rate of progression of islet autoimmunity were lower in Hispanic compared with NHW at-risk individuals, while significant differences in the development of type 1 diabetes were limited to children <12 years old and were modified by BMI.
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http://dx.doi.org/10.1007/s00125-018-4660-9DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6611550PMC
September 2018

Racial/Ethnic Minority Youth With Recent-Onset Type 1 Diabetes Have Poor Prognostic Factors.

Diabetes Care 2018 05 1;41(5):1017-1024. Epub 2018 Mar 1.

Children's Mercy Kansas City, Kansas City, MO.

Objective: To compare races/ethnicities for characteristics, at type 1 diabetes diagnosis and during the first 3 years postdiagnosis, known to influence long-term health outcomes.

Research Design And Methods: We analyzed 927 Pediatric Diabetes Consortium (PDC) participants <19 years old (631 non-Hispanic white [NHW], 216 Hispanic, and 80 African American [AA]) diagnosed with type 1 diabetes and followed for a median of 3.0 years (interquartile range 2.2-3.6). Demographic and clinical data were collected from medical records and patient/parent interviews. Partial remission period or "honeymoon" was defined as insulin dose-adjusted hemoglobin A (IDAA1c) ≤9.0%. We used logistic, linear, and multinomial regression models, as well as repeated-measures logistic and linear regression models. Models were adjusted for known confounders.

Results: AA subjects, compared with NHW, at diagnosis, were in a higher age- and sex-adjusted BMI percentile (BMI%), had more advanced pubertal development, and had higher frequency of presentation in diabetic ketoacidosis, largely explained by socioeconomic factors. During the first 3 years, AA subjects were more likely to have hypertension and severe hypoglycemia events; had trajectories with higher hemoglobin A, BMI%, insulin doses, and IDAA1c; and were less likely to enter the partial remission period. Hispanics, compared with NHWs, had higher BMI% at diagnosis and over the three subsequent years. During the 3 years postdiagnosis, Hispanics had higher prevalence of dyslipidemia and maintained trajectories of higher insulin doses and IDAA1c.

Conclusions: Youth of minority race/ethnicity have increased markers of poor prognosis of type 1 diabetes at diagnosis and 3 years postdiagnosis, possibly contributing to higher risk of long-term diabetes complications compared with NHWs.
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http://dx.doi.org/10.2337/dc17-2335DOI Listing
May 2018

Autoimmune Diseases in Children and Adults With Type 1 Diabetes From the T1D Exchange Clinic Registry.

Authors:
Mustafa Tosur

Clin Pediatr (Phila) 2018 05 27;57(5):621. Epub 2017 Sep 27.

1 Texas Children's Hospital, Baylor College of Medicine, Houston, TX, USA.

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http://dx.doi.org/10.1177/0009922817733304DOI Listing
May 2018

Diencephalic syndrome: a rare cause of failure to thrive.

BMJ Case Rep 2017 Jul 6;2017. Epub 2017 Jul 6.

Baylor College of Medicine, Houston, Texas, USA.

Timely diagnosis of diencephalic syndrome is not often the case for patients presenting with failure to thrive (FTT) because of its rarity and lack of specific symptoms. Herein, we report two cases of diencephalic syndrome (2-year-old girl and 10-month-old boy) presenting with severe emaciation. Both patients had histories of poor weight gain for months despite having good appetites prior to diagnosis. Initial work-up did not reveal the diagnosis. Horizontal nystagmus was noted in both patients: by a neurologist in the first patient and by a family member in the second patient. MRI of the brain showed large suprasellar mass and pilocytic astrocytoma was confirmed by pathology in each case. The patients were started on appropriate chemotherapy with interval improvements in weight gain. These cases illustrate the importance of cranial imaging and consideration of diencephalic syndrome for children presenting with FTT despite normal or increased caloric intake.
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http://dx.doi.org/10.1136/bcr-2017-220171DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5534923PMC
July 2017

A Novel Intragenic Mutation Associated With Congenital Hyperinsulinism.

Glob Pediatr Health 2017 17;4:2333794X17703462. Epub 2017 Apr 17.

Texas Children's Hospital, Baylor College of Medicine, Houston, TX, USA.

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http://dx.doi.org/10.1177/2333794X17703462DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5406188PMC
April 2017

Heterogeneity of Type 1 Diabetes: The Effect of Ethnicity.

Curr Diabetes Rev 2018 ;14(3):266-272

Diabetes and Endocrinology Section, Texas Children's Hospital, Baylor College of Medicine, 6701 Fannin Street, Ste 1020 Houston, Texas 77030, United States.

Background: Most of the current understanding of type 1 diabetes (T1D) etiology and pathogenesis stemmed from studies conducted in majoritarily Non-Hispanic White (NHW) populations. However, evidence is emerging that unique mechanisms of disease may contribute to the development of T1D in individuals of Hispanic ethnicity.

Objective: We reviewed the currently available literature on genetic, immunologic, metabolic and clinical characteristics of T1D in Hispanic as compared with NHW individuals.

Methods: We searched PubMed, Google Scholar, and authors' bibliographies to collect information from relevant articles on the influence of ethnicity on T1D etiology and pathogenesis.

Results: There are significant epidemiological variation based on ethnicity, with consistently higher T1D incidence and prevalence rate in NHWs than Hispanics. The frequencies of T1D high-risk HLA haplotypes and genotypes, as well as their susceptibility or protective effects show considerable ethnic differences. There are conflicting data on immunologic factors (e.g. islet autoantibody positivity) and markers of beta-cell function (e.g., C-peptide levels), as well as in some clinical characteristics (e.g. frequencies of diabetic ketoacidosis and severe hypoglycemia), while age of onset is consistently similar between both groups. Higher prevalence of obesity, less intensive diabetes management, and poorer glycemic control were reported in Hispanics. Accordingly, ethnic disparities in clinical outcomes have been demonstrated as well.

Conclusion: There are considerable differences in T1D characteristics between NHWs and Hispanics. Better insight into these ethnic differences would not only affect patient care of patients with T1D, but may also inform the design of future prediction and prevention trials.
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http://dx.doi.org/10.2174/1573399813666170502105402DOI Listing
October 2018

Modified nomogram for derivation of renal threshold phosphate concentration.

Authors:
Mustafa Tosur

Int Urol Nephrol 2017 07 18;49(7):1309-1310. Epub 2017 Apr 18.

Department of Pediatrics, Section of Endocrinology and Diabetes, Texas Children's Hospital, Baylor College of Medicine, 6701 Fannin St, Suite 10.20, Houston, TX, 77030, USA.

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http://dx.doi.org/10.1007/s11255-017-1588-9DOI Listing
July 2017

Incidental Hypercalcemia Caused by Primary Hyperparathyroidism with Rapid Progression to Renal Complications in a Child.

Clin Pediatr (Phila) 2018 01 18;57(1):117-120. Epub 2017 Jan 18.

1 University of Texas Medical Branch at Galveston, TX, USA.

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http://dx.doi.org/10.1177/0009922816685822DOI Listing
January 2018

Persistence of müllerian duct structures in a genetic male with distal monosomy 10q.

Am J Med Genet A 2015 Apr;167A(4):791-6

Department of Pediatrics, University of Texas Medical Branch, Galveston, Texas.

Persistent müllerian duct syndrome (PMD) with antimüllerian hormone (AMH) deficiency is usually associated with mutations or deletions of the AMH gene, although many cases have no identified gene association. We report on a genetic male with PMD and AMH deficiency associated with distal monosomy 10q. A term 3,230 g infant was born to a healthy 27-year-old. Fetal ultrasound had shown possible genital ambiguity. Postnatal exam showed a 0.5 cm phallus with basal meatus, normal scrotum with no palpable gonads, no vaginal orifice, and a rectal fistula with an imperforate anus. Voiding cystourethrogram with ultrasound, cystoscopy, and laparoscopy showed normal bladder, urethral orifice, distal vagina, cervix, and bilateral abdominal testis. At 24 hours of life, testosterone was within normal range with low AMH level. Chromosome microarray analysis showed 46, XY, del10(10q25.3q26.13) involving an 8.2 MB interstitial deletion. Whole exome sequencing identified a NOTCH2 variant (1p11.2). AMH sequencing revealed no abnormalities. Following multidisciplinary team and parent discussion, male gender was assigned. Testosterone treatment resulted in penile length of 1.5 cm. Bilateral orchiopexy and posterior sagittal anorectoplasty were performed at 11 months of age; rudimentary müllerian structures were identified. This observation suggests an association of 10qter elements with male differentiation including AMH expression and is similar to a patient with 46, XY, del(10q26.1) in which AMH levels were not reported. Regional candidate genes include FGFR2 (10q26.13). The possible contribution of a NOTCH2 variant cannot be excluded.
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http://dx.doi.org/10.1002/ajmg.a.37014DOI Listing
April 2015