Publications by authors named "Oksana Ocheretina"

24 Publications

  • Page 1 of 1

Drug-resistant TB prevalence study in 5 health institutions in Haiti.

PLoS One 2021 18;16(3):e0248707. Epub 2021 Mar 18.

Les Centres GHESKIO, Port-au-Prince, Haiti.

Objectives: Tuberculosis (TB) is the leading infectious cause of death in the world. Multi-drug resistant TB (MDR-TB) is a major public health problem as treatment is long, costly, and associated to poor outcomes. Here, we report epidemiological data on the prevalence of drug-resistant TB in Haiti.

Methods: This cross-sectional prevalence study was conducted in five health centers across Haiti. Adult, microbiologically confirmed pulmonary TB patients were included. Molecular genotyping (rpoB gene sequencing and spoligotyping) and phenotypic drug susceptibility testing were used to characterize rifampin-resistant MTB isolates detected by Xpert MTB/RIF.

Results: Between April 2016 and February 2018, 2,777 patients were diagnosed with pulmonary TB by Xpert MTB/RIF screening and positive MTB cultures. A total of 74 (2.7%) patients were infected by a drug-resistant (DR-TB) M. tuberculosis strain. Overall HIV prevalence was 14.1%. Patients with HIV infection were at a significantly higher risk for infection with DR-TB strains compared to pan-susceptible strains (28.4% vs. 13.7%, adjusted odds ratio 2.6, 95% confidence interval 1.5-4.4, P = 0.001). Among the detected DR-TB strains, T1 (29.3%), LAM9 (13.3%), and H3 (10.7%) were the most frequent clades. In comparison with previous spoligotypes studies with data collected in 2000-2002 and in 2008-2009 on both sensitive and resistant strains of TB in Haiti, we observed a significant increase in the prevalence of the drug-resistant MTB Spoligo-International-Types (SIT) 137 (X2 clade: 8.1% vs. 0.3% in 2000-02 and 0.9% in 2008-09, p<0.001), 5 (T1 clade: 6.8% vs 1.9 in 2000-02 and 1.7% in 2008-09, P = 0.034) and 455 (T1 clade: 5.4% vs 1.6% and 1.1%, P = 0.029). Newly detected spoligotypes (SIT 6, 7, 373, 909 and 1624) were also recorded.

Conclusion: This study describes the genotypic and phenotypic characteristics of DR-TB strains circulating in Haiti from April 2016 to February 2018. Newly detected MTB clades harboring multi-drug resistance patterns among the Haitian population as well as the higher risk of MDR-TB infection in HIV-positive people highlights the epidemiological relevance of these surveillance data. The importance of detecting RIF-resistant patients, as proxy for MDR-TB in peripheral sites via molecular techniques, is particularly important to provide adequate patient case management, prevent the transmission of resistant strains in the community and to contribute to the surveillance of resistant strains.
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http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0248707PLOS
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7971505PMC
March 2021

Multidrug-resistant Pseudomonas aeruginosa in healthcare facilities in Port-au-Prince, Haiti.

J Glob Antimicrob Resist 2021 Mar 1;25:60-65. Epub 2021 Mar 1.

Center for Global Health, Weill Cornell Medicine, New York, NY, USA.

Objectives: Pseudomonas aeruginosa is a leading cause of opportunistic infections worldwide, particularly in healthcare settings, and frequently demonstrates resistance to commonly prescribed antimicrobials. Carbapenem resistance is prevalent worldwide, however there are currently limited data available from Haiti. The aim of this study was to characterise and document this phenotype in Port-au-Prince, Haiti, to further inform the need for appropriate infection control, empirical treatment guidelines and laboratory screening measures, both in Haiti and globally.

Methods: A total of 50 P. aeruginosa isolates were characterised by multilocus sequence typing (MLST) and antimicrobial susceptibility testing, of which 8 isolates were also subjected to whole-genome sequencing (WGS) to identify potential genetic correlations of phenotypic resistance.

Results: By MLST, 23 sequence types (STs) were identified, including 13 new STs. Nineteen isolates belonged to a single, previously characterised ST (ST654), all of which demonstrated a multidrug-resistant phenotype, including resistance to meropenem, imipenem and ceftazidime; two isolates were also resistant to colistin. WGS revealed the presence of genes encoding several previously characterised resistance determinants in ST654; notably ACC(6')-Ib3-cr and GES-7. Metallo-β-lactamase genes (bla) were also detected in three isolates.

Conclusion: These findings confirm that drug-resistant clones of P. aeruginosa are present in Haiti, supporting the need for appropriate screening and control measures and confirming that drug-resistant micro-organisms pose a global threat. Further investigations are required to guide appropriate antimicrobial prescribing in this region.
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http://dx.doi.org/10.1016/j.jgar.2021.02.016DOI Listing
March 2021

Diagnosis of Tuberculosis Using Gastric Aspirates in Pediatric Patients in Haiti.

J Pediatric Infect Dis Soc 2021 Feb;10(1):22-26

Division of Infectious Disease and International Health, Dartmouth Hitchcock Medical Center, Lebanon New Hampshire, USA.

Background: We aimed to determine whether the Xpert MTB/RIF (Xpert) assay is a useful adjunct to culture for the rapid diagnosis of tuberculosis (TB) using gastric lavage aspirates (GLAs) in children aged < 5 years.

Methods: We reviewed the yield from diagnostic modalities in children suspected of having TB followed at an infectious disease research and treatment center in Port-au-Prince, Haiti, from 2011 to 2016.

Results: In 187 children clinically diagnosed with TB, a microbiologic diagnosis could be established in 40 (21%). Cultures, Xpert, and smears were positive in 30 (19%), 28 (17%), and 3 (1.6%) children, respectively. Ten cases that would not have been diagnosed by culture alone were found by the use of the Xpert assay. Collecting 2 GLA samples optimized microbiologic yield.

Conclusions: In GLAs, Xpert increased the yield of microbiologically documented cases by 33%. Additionally, the rapidity of diagnosis potentially makes Xpert a valuable adjunct in initiating treatment for TB in children. Smear microscopy has low sensitivity in GLA and did not add to the documented cases. Our findings also highlight the low rate of microbiologic confirmation of clinically diagnosed TB.
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http://dx.doi.org/10.1093/jpids/piaa012DOI Listing
February 2021

Improved Outcomes With High-dose Isoniazid in Multidrug-resistant Tuberculosis Treatment in Haiti.

Clin Infect Dis 2019 08;69(4):717-719

Division of Global Health Equity, Brigham and Women's Hospital, Harvard Medical School, Boston, Massachusetts.

We report outcomes for a cohort of patients with multidrug-resistant tuberculosis who received high-dose isoniazid in Haiti. Patients who received high-dose isoniazid had a faster time to culture conversion and higher odds of successful outcome, despite high-level isoniazid resistance. This suggests high-dose isoniazid may have effectiveness even with phenotypic resistance.
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http://dx.doi.org/10.1093/cid/ciz039DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7322692PMC
August 2019

Differentially Detectable Mycobacterium tuberculosis Cells in Sputum from Treatment-Naive Subjects in Haiti and Their Proportionate Increase after Initiation of Treatment.

mBio 2018 11 20;9(6). Epub 2018 Nov 20.

Department of Microbiology & Immunology, Weill Cornell Medicine, New York, New York, USA

Recent reports indicate that the sputum of 80% or more of treatment-naive subjects with tuberculosis recruited in England or South Africa contained more viable cells detected by limiting dilution (LD) in liquid culture than detected as CFU. Efforts to generate such differentially detectable (DD) populations have been difficult to reproduce, and the LD assay is prone to artifact. Here, we applied a stringent version of the LD assay to sputum from 33 treatment-naive, HIV-negative Haitian subjects with drug-sensitive tuberculosis (TB) and to a second sputum sample after two weeks of standard treatment with isoniazid, rifampin, pyrazinamide, and ethambutol (HRZE) for 13 of these subjects. Twenty-one percent had statistically defined levels of DD in their pretreatment sputum at an average proportional excess over CFU of 3-fold. Sixty-nine percent of those who received HRZE had statistically defined levels of DD in their sputum, and of these, the mean proportionate excess over CFU was 7.9-fold. Thus, DD is detectable in pretreatment sputum from a significant proportion of subjects in the Western Hemisphere, and certain drugs or drug regimens, while reducing CFU, may at the same time increase the proportional representation of DD among the surviving bacilli. Monitoring DD may improve our ability to predict the efficacy of efforts to shorten treatment. Measurement of the reduction in CFU in sputum of patients with TB up to 2 weeks after the initiation of treatment is the gateway test for a new TB treatment. Reports have suggested that CFU assays fail to detect the majority of viable cells in sputum samples from the majority of patients when the number of is estimated by limiting dilution (LD). In an effort to avoid potential methodologic confounders, we applied a modified version of the LD assay in a study of a geographically distinct population. We confirmed that differentially detectable (DD) is often found before treatment, albeit at lower proportionate levels than in earlier reports. Strikingly, the prevalence and proportionate representation of DD increased during standard treatment. Sublethal exposure to certain antibiotics may help generate DD cells or enrich their representation among the surviving bacteria, and this may contribute to the need for prolonged treatment with those agents in order to achieve durable cures.
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http://dx.doi.org/10.1128/mBio.02192-18DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6247085PMC
November 2018

Genotypic drug resistance using whole-genome sequencing of Mycobacterium tuberculosis clinical isolates from North-western Tanzania.

Tuberculosis (Edinb) 2018 03 21;109:97-101. Epub 2018 Feb 21.

Center for Global Health, Division of Infectious Diseases, Weill Cornell Medical College, New York, NY, USA.

Background: Drug resistant Tuberculosis (TB) is considered a global public health threat. Whole-genome sequencing (WGS) is a new technology for tuberculosis (TB) diagnostics and is capable of providing rapid drug resistance profiles and genotypes for epidemiologic surveillance. Therefore, we used WGS to determine genotypic drug resistance profiles and genetic diversity of drug resistant Mycobacterium tuberculosis isolates from Mwanza, North-western Tanzania.

Methods: A cross-sectional study was conducted at the Bugando Medical Center (BMC) from September 2014 to June 2015. Consecutively, smear-positive newly diagnosed TB patients aged ≥18 years were enrolled. Sputum samples were cultured on Löwenstein-Jensen (LJ) slants. Mycobacterial genomic DNA was extracted for WGS to determine drug resistant mutations for first and second line drugs as well as the spoligotypes.

Results: A total of 78 newly diagnosed patients with pulmonary TB with a median age of 37 [IQR: 30-46] years were enrolled. Of these, 57.8% (45/74) were males and 34.6% (27/78) were HIV positive. Mycobacterium tuberculosis genomic DNA for WGS was obtained from isolates in 74 (94.9%) patients. Of the 74 isolates, six (8.1%) isolates harbored mutations for resistance to at least one drug. The resistance to the drugs was isoniazid 3/74 (4.1%), rifampicin mono-resistant 2/74 (2.7%), ethambutol 2/74 (2.7%) and streptomycin 1/74 (1.4%). None was isoniazid mono-resistant. Of the 74 only one (1.4%) patient had MDR-TB. The resistance to ethionamide, the second line drug, was detected in one patient (1.4%). None was resistant to pyrazinamide, fluoroquinolones, kanamycin, amikacin, or capreomycin. The mutations detected were mabA-inhA promoter region C(-15)T and katG Ser513Thr for isoniazid; rpoB His526Leu and rpoB Ser531Leu for rifampicin; embB Met306Val and embB Met306Ile for ethambutol; rpsL Lys43Arg for streptomycin; and mabA-inhA promoter region C(-15)T for ethionamide. The spoligotypes of the drug resistant Mycobacterium tuberculosis were distinct to all six isolates and belonged to T1, T2, T3-ETH, CAS1-DELHI, EAI5 and LAM11-ZWE lineages.

Conclusion: The genetic drug resistance profile of Mycobacterium tuberculosis isolates from North-western Tanzania comprises of the common previously reported mutations. The prevalence of resistance to first and second line drugs including MDR-TB is low. Six drug resistant strains exhibited different spoligotypes, suggesting limited transmission of drug resistant strains in the region.
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http://dx.doi.org/10.1016/j.tube.2018.02.004DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5912878PMC
March 2018

Active Tuberculosis Case Finding in Haiti.

Am J Trop Med Hyg 2017 Aug 19;97(2):433-435. Epub 2017 Jul 19.

Weill Cornell Medical College, New York, New York.

In 2010, Haiti suffered from a devastating earthquake; data on the impact on the tuberculosis (TB) epidemic are limited. From January to June 2013, we conducted active case finding at the household level in a slum in Port-au-Prince. Community health workers identified individuals with cough ≥ 2 weeks, and referred them for evaluation. Contact tracing was conducted for patients with active TB. Of an estimated 7,500 residents screened, 394 (5%) had cough and were tested for TB. One hundred (25%) were diagnosed with active TB; 53 (53%) were smear positive. Ninety of these TB index cases provided 317 contacts, and 44 (14%) were diagnosed with active TB; 17 (39%) were smear positive. Overall, 144 TB cases were detected in 6 months (1,920/100,000; national estimate 200/100,000). We found a high burden of undiagnosed TB in Port-au-Prince 3 years after the earthquake. Further assessment of the burden of TB is indicated.
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http://dx.doi.org/10.4269/ajtmh.16-0674DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5544073PMC
August 2017

Chlamydia trachomatis, Neisseria gonorrhoeae, and Trichomonas vaginalis screening and treatment of pregnant women in Port-au-Prince, Haiti.

Int J STD AIDS 2017 10 29;28(11):1130-1134. Epub 2017 Jan 29.

2 Department of Medicine, University of California Los Angeles, Los Angeles, CA, USA.

In Haiti, routine screening for Chlamydia trachomatis (CT), Neisseria gonorrhoeae (NG), and Trichomonas vaginalis (TV) among pregnant women is not conducted; yet these sexually transmitted infections (STIs) are associated with adverse birth and newborn health outcomes. We aimed to assess the acceptability and feasibility of screening and the prevalence of STIs among pregnant women in Port-au-Prince, Haiti. Pregnant women of at least 18 years of age who attend Haitian Study Group for Kaposi's sarcoma and Opportunistic Infections (GHESKIO) clinics in Port-au-Prince, Haiti provided self-collected vaginal swab specimens. Laboratory testing was done with Xpert® CT/NG and Xpert® TV. The results of this study showed that of the 322 pregnant women who visited GHESKIO for their regular scheduled appointments, 300 (93.2%) consented for CT, NG, and TV testing. Of those, 107 women (35.7%) tested positive for at least one STI. There were 42 (14.7%) cases of CT, 8 (2.8%) NG, and 83 (29.0%) TV infections. Most infections were treated - 122 of 133 (91.7%). In summary, we found that it was highly acceptable and feasible to implement CT, NG, and TV screening among pregnant women in Port-au-Prince, Haiti. We found high prevalence of STIs among pregnant women, which suggest that STI screening in this population may be warranted.
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http://dx.doi.org/10.1177/0956462416689755DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5837282PMC
October 2017

Clinical Features of Human Immunodeficiency Virus-Infected Patients Presenting with Cholera in Port-au-Prince, Haiti.

Am J Trop Med Hyg 2016 Nov 22;95(5):999-1003. Epub 2016 Aug 22.

Center for Global Health, Weill Cornell Medical College, New York, New York.

Human immunodeficiency virus (HIV) infection has been postulated to alter the natural history of cholera, including increased susceptibility to infection, severity of illness, and chronic carriage of Vibrio cholerae Haiti has a generalized HIV epidemic with an adult HIV prevalence of 1.9% and recently suffered a cholera epidemic. We conducted a prospective study at the cholera treatment center (CTC) of GHESKIO in Haiti to characterize the coinfection. Adults admitted at the CTC for acute diarrhea were invited to participate in the study. Vital signs, frequency, and volume of stools and/or vomiting were monitored, and single-dose doxycycline was administered. After counseling, participants were screened for HIV by enzyme-linked immunosorbent assay and for cholera by culture. Of 729 adults admitted to the CTC, 99 (13.6%) had HIV infection, and 457 (63%) had culture-confirmed cholera. HIV prevalence was three times higher in patients without cholera (23%, 63/272) than in those with culture-confirmed cholera (7.9%, 36/457). HIV prevalence in patients with culture-confirmed cholera (7.9%) was four times higher than the adult prevalence in Port-au-Prince (1.9%). Of the 36 HIV-infected patients with cholera, 25 (69%) had moderate/severe dehydration versus 302/421 (72%) in the HIV negative. Of 30 HIV-infected patients with weekly stool cultures performed after discharge, 29 (97%) were negative at week 1. Of 50 HIV-negative patients with weekly stool cultures, 49 (98%) were negative at week 1. In countries with endemic HIV infection, clinicians should consider screening patients presenting with suspected cholera for HIV coinfection.
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http://dx.doi.org/10.4269/ajtmh.16-0105DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5094251PMC
November 2016

False-positive rifampin resistant results with Xpert MTB/RIF version 4 assay in clinical samples with a low bacterial load.

Diagn Microbiol Infect Dis 2016 May 15;85(1):53-5. Epub 2016 Jan 15.

Center for Global Health, Division of Infectious Diseases, Department of Medicine, Weill Cornell Medical College, New York, New York; Les Centres GHESKIO, Port-au-Prince, Haiti.

We report investigation of 22 TB cases with positive Xpert MTB/RIF result for resistance to Rifampin and "Very Low" MTB detection level. Twelve cases were false positive without rpoB mutations, 2 were false-positives with a silent mutation in rpoB codon T508, and only 10 were true positives.
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http://dx.doi.org/10.1016/j.diagmicrobio.2016.01.009DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4841693PMC
May 2016

Tuberculosis in the aftermath of the 2010 earthquake in Haiti.

Bull World Health Organ 2015 Jul 1;93(7):498-502. Epub 2015 May 1.

Haitian Study Group for Kaposi's Sarcoma and Opportunistic Infections (GHESKIO), 33 Boulevard Harry Truman, BP 15727, Port-au-Prince, Haiti .

Problem: In 2010, Haiti sustained a devastating earthquake that crippled the health-care infrastructure in the capital city, Port-au-Prince, and left 1.5 million people homeless. Subsequently, there was an increase in reported tuberculosis in the affected population.

Approach: We conducted active tuberculosis case finding in a camp for internally displaced persons and a nearby slum. Community health workers screened for tuberculosis at the household level. People with persistent cough were referred to a physician. The National Tuberculosis Program continued its national tuberculosis reporting system.

Local Setting: Even before the earthquake, Haiti had the highest tuberculosis incidence in the Americas. About half of the tuberculosis cases occur in the Port-au-Prince region.

Relevant Changes: The number of reported tuberculosis cases in Haiti has increased after the earthquake, but data are too limited to determine if this is due to an increase in tuberculosis burden or to improved case detection. Compared to previous national estimates (230 per 100,000 population), undiagnosed tuberculosis was threefold higher in a camp for internally displaced persons (693 per 100,000) and fivefold higher in an urban slum (1165 per 100,000). With funding from the World Health Organization (WHO), active case finding is now being done systematically in slums and camps.

Lessons Learnt: Household-level screening for prolonged cough was effective in identifying patients with active tuberculosis in this study. Without accurate data, early detection of rising tuberculosis rates is challenging; data collection should be incorporated into pragmatic disease response programmes.
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http://dx.doi.org/10.2471/BLT.14.145649DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4490810PMC
July 2015

Whole Genome Sequencing Investigation of a Tuberculosis Outbreak in Port-au-Prince, Haiti Caused by a Strain with a "Low-Level" rpoB Mutation L511P - Insights into a Mechanism of Resistance Escalation.

PLoS One 2015 3;10(6):e0129207. Epub 2015 Jun 3.

Center for Global Health, Division of Infectious Diseases, Department of Medicine, Weill Cornell Medical College, New York, New York, United States of America.

The World Health Organization recommends diagnosing Multidrug-Resistant Tuberculosis (MDR-TB) in high burden countries by detection of mutations in Rifampin (RIF) Resistance Determining Region of Mycobacterium tuberculosis rpoB gene with rapid molecular tests GeneXpert MTB/RIF and Hain MTBDRplus. Such mutations are found in >95% of Mycobacterium tuberculosis strains resistant to RIF by conventional culture-based drug susceptibility testing (DST). However routine diagnostic screening with molecular tests uncovered specific "low level" rpoB mutations conferring resistance to RIF below the critical concentration of 1 μg/ml in some phenotypically susceptible strains. Cases with discrepant phenotypic (susceptible) and genotypic (resistant) results for resistance to RIF account for at least 10% of resistant diagnoses by molecular tests and urgently require new guidelines to inform therapeutic decision making. Eight strains with a "low level" rpoB mutation L511P were isolated by GHESKIO laboratory between 2008 and 2012 from 6 HIV-negative and 2 HIV-positive patients during routine molecular testing. Five isolates with a single L511P mutation and two isolates with double mutation L511P&M515T had MICs for RIF between 0.125 and 0.5 μg/ml and tested susceptible in culture-based DST. The eighth isolate carried a double mutation L511P&D516C and was phenotypically resistant to RIF. All eight strains shared the same spoligotype SIT 53 commonly found in Haiti but classic epidemiological investigation failed to uncover direct contacts between the patients. Whole Genome Sequencing (WGS) revealed that L511P cluster isolates resulted from a clonal expansion of an ancestral strain resistant to Isoniazid and to a very low level of RIF. Under the selective pressure of RIF-based therapy the strain acquired mutation in the M306 codon of embB followed by secondary mutations in rpoB and escalation of resistance level. This scenario highlights the importance of subcritical resistance to RIF for both clinical management of patients and public health and provides support for introducing rpoB mutations as proxy for MICs into laboratory diagnosis of RIF resistance. This study illustrates that WGS is a promising multi-purpose genotyping tool for high-burden settings as it provides both "gold standard" sequencing results for prediction of drug susceptibility and a high-resolution data for epidemiological investigation in a single assay.
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http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0129207PLOS
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4454571PMC
April 2016

High-throughput mycobacterial interspersed repetitive-unit-variable-number tandem-repeat genotyping for Mycobacterium tuberculosis epidemiological studies.

J Clin Microbiol 2015 Feb 26;53(2):498-503. Epub 2014 Nov 26.

Laboratoire des Pathogènes Emergents (LPE), Fondation Mérieux-Centre International de Recherche en Infectiologie (CIRI), Lyon, France.

The emergence of drug-resistant forms of tuberculosis (TB) represents a major public health concern. Understanding the transmission routes of the disease is a key factor for its control and for the implementation of efficient interventions. Mycobacterial interspersed repetitive-unit-variable-number tandem-repeat (MIRU-VNTR) marker typing is a well-described method for lineage identification and transmission tracking. However, the conventional manual genotyping technique is cumbersome and time-consuming and entails many risks for errors, thus hindering its implementation and dissemination. We describe here a new approach using the QIAxcel system, an automated high-throughput capillary electrophoresis system that also carries out allele calling. This automated method was assessed on 1,824 amplicons from 82 TB isolates and tested with sets of markers of 15 or 24 loci. Overall allele-calling concordance between the methods from 140 to 1,317 bp was 98.9%. DNA concentrations and repeatability and reproducibility performances showed no biases in allele calling. Furthermore, turnaround time using this automated system was reduced by 81% compared to the conventional manual agarose gel method. In sum, this new automated method facilitates MIRU-VNTR genotyping and provides reliable results. Therefore, it is well suited for field genotyping. The implementation of this method will help to achieve accurate and cost-effective epidemiological studies, especially in countries with a high prevalence of TB, where the high number of strains complicates the surveillance of circulating lineages and requires efficient interventions to be carried out in an urgent manner.
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http://dx.doi.org/10.1128/JCM.01611-14DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4298502PMC
February 2015

Treatment outcomes for patients with multidrug-resistant tuberculosis in post-earthquake Port-au-Prince, Haiti.

Am J Trop Med Hyg 2014 Oct 28;91(4):715-21. Epub 2014 Jul 28.

Les Centres Groupe Haïtien d'Etude du Sarcome de Kaposi et des Infections Opportunistes (GHESKIO), Port-au-Prince, Haiti; Division of Global Health Equity, Brigham and Women's Hospital, Harvard Medical School, Boston, Massachusetts; Masters of Science in Public Health, Johns Hopkins Bloomberg School of Public Health, Baltimore, Maryland; Division of Infectious Diseases, Center for Global Health, Weill Cornell Medical College, New York, New York.

We report outcomes and 12-month survival for the first cohort of patients to undergo multidrug-resistant tuberculosis (MDR-TB) treatment after the earthquake in Haiti. From March 3, 2010 to March 28, 2013, 110 patients initiated treatment of laboratory-confirmed MDR-TB at the Groupe Haïtien d'Etude du Sarcome de Kaposi et des Infections Opportunistes (GHESKIO) Center in Port-au-Prince, Haiti. Twenty-seven patients (25%) were human immunodeficiency virus (HIV)-positive. As of October 31, 2013, 95 (86%) patients were either cured or alive on treatment, 4 (4%) patients defaulted, and 11 (10%) patients died. Culture conversion occurred by 30 days in 14 (13%) patients, 60 days in 49 (45%) patients, and 90 days in 81 (74%) patients. The probabilities of survival to 12 months were 96% (95% confidence interval [95% CI] = 89-99) and 85% (95% CI = 64-94) for HIV-negative and -positive patients, respectively. Despite adverse conditions, outcomes for patients with MDR-TB are highly encouraging. Major efforts are underway to scale up community directly observed therapy and expand care to other regions of Haiti.
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http://dx.doi.org/10.4269/ajtmh.14-0161DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4183393PMC
October 2014

A multiplex PCR/LDR assay for simultaneous detection and identification of the NIAID category B bacterial food and water-borne pathogens.

Diagn Microbiol Infect Dis 2014 Jun 12;79(2):135-40. Epub 2014 Mar 12.

Department of Microbiology and Immunology, Weill Medical College of Cornell University, Box 62, New York, NY 10021. Electronic address:

Enteric pathogens that cause gastroenteritis remain a major global health concern. The goal of this study was to develop a multiplex PCR/ligation detection reaction (LDR) assay for the detection of all NIAID category B bacterial food and water-borne pathogens directly from stool specimens. To validate the PCR/LDR assay, clinical isolates of Campylobacter spp., Vibrio spp., Shigella spp., Salmonella spp., Listeria monocytogenes, Yersinia enterocolitica, and diarrheagenic Escherichia coli were tested. The sensitivity and specificity of the assay were assessed using a large number of seeded culture-negative stool specimens and a smaller set of clinical specimens from Haiti. The overall sensitivity ranged from 91% to 100% (median 100%) depending on the species. For the majority of organisms, the sensitivity was 100%. The overall specificity based on initial testing ranged from 98% to 100% depending on the species. After additional testing of discordant samples, the lowest specificity was 99.4%. PCR/LDR detected additional category B agents (particularly diarrheagenic E. coli) in 11/40 specimens from Haiti that were culture-positive for V. cholerae and in approximately 1% of routine culture-negative stool specimens from a hospital in New York. This study demonstrated the ability of the PCR/LDR assay to detect a large comprehensive panel of category B enteric bacterial pathogens as well as mixed infections. This type of assay has the potential to provide earlier warnings of possible public health threats and more accurate surveillance of food and water-borne pathogens.
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http://dx.doi.org/10.1016/j.diagmicrobio.2014.02.022DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4028377PMC
June 2014

Correlation between genotypic and phenotypic testing for resistance to rifampin in Mycobacterium tuberculosis clinical isolates in Haiti: investigation of cases with discrepant susceptibility results.

PLoS One 2014 5;9(3):e90569. Epub 2014 Mar 5.

Center for Global Health, Division of Infectious Diseases, Department of Medicine, Weill Cornell Medical College, New York, New York, United States of America.

The World Health Organization has recommended use of molecular-based tests MTBDRplus and GeneXpert MTB/RIF to diagnose multidrug-resistant tuberculosis in developing and high-burden countries. Both tests are based on detection of mutations in the Rifampin (RIF) Resistance-Determining Region of DNA-dependent RNA Polymerase gene (rpoB). Such mutations are found in 95-98% of Mycobacterium tuberculosis strains determined to be RIF-resistant by the "gold standard" culture-based drug susceptibility testing (DST). We report the phenotypic and genotypic characterization of 153 consecutive clinical Mycobacterium tuberculosis strains diagnosed as RIF-resistant by molecular tests in our laboratory in Port-au-Prince, Haiti. 133 isolates (86.9%) were resistant to both RIF and Isoniazid and 4 isolates (2.6%) were RIF mono-resistant in MGIT SIRE liquid culture-based DST. However the remaining 16 isolates (10.5%) tested RIF-sensitive by the assay. Five strains with discordant genotypic and phenotypic susceptibility results had RIF minimal inhibitory concentration (MIC) close to the cut-off value of 1 µg/ml used in phenotypic susceptibility assays and were confirmed as resistant by DST on solid media. Nine strains had sub-critical RIF MICs ranging from 0.063 to 0.5 µg/ml. Finally two strains were pan-susceptible and harbored a silent rpoB mutation. Our data indicate that not only detection of the presence but also identification of the nature of rpoB mutation is needed to accurately diagnose resistance to RIF in Mycobacterium tuberculosis. Observed clinical significance of low-level resistance to RIF supports the re-evaluation of the present critical concentration of the drug used in culture-based DST assays.
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http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0090569PLOS
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3944071PMC
January 2015

The aetiology of vaginal symptoms in rural Haiti.

Int J STD AIDS 2014 Aug 18;25(9):669-75. Epub 2013 Dec 18.

University of California Los Angeles, Los Angeles, CA, USA.

Vaginal symptoms are a common chief complaint amongst women visiting outpatient clinics in rural Haiti. A systematic sample of 206 consecutive women over age 18 with gynaecological symptoms underwent gynaecologic examination and laboratory testing for chlamydia, gonorrhoea, syphilis, HIV infection, trichomoniasis, candidiasis, and bacterial vaginosis. Among 206 women, 174 (84%) presented with vaginal discharge, 165 (80%) with vaginal itching, 123 (60%) with vaginal pain or dysuria, and 18 (9%) with non-traumatic vaginal sores or boils. Laboratory results were positive forChlamydia trachomatisin 5.4% (11/203), syphilis in 3.5% (7/202), HIV in 1.0% (2/200), andNeisseria gonorrhoeaein 1.0% (2/203). Among those that had microscopy, hyphae suggestive of candidiasis were visualized in 2.2% (1/45) and no cases of trichomoniasis were diagnosed 0% (0/45). Bacterial vaginosis was diagnosed in 28.3% (13/46). The prevalence of chlamydia was 4.9 (95% CI: 1.3-17.7) times greater among those 25 years of age and under (10.8%) than those older (2.3%). Chlamydia and bacterial vaginosis were the most common sexually transmitted infection and vaginal condition, respectively, in this study of rural Haitian adult women. The higher risk of chlamydia in younger women suggests education and screening programmes in young women should be considered.
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http://dx.doi.org/10.1177/0956462413516300DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4712119PMC
August 2014

Epidemiology and genetic diversity of multidrug-resistant tuberculosis in East Africa.

Tuberculosis (Edinb) 2014 Jan 7;94(1):1-7. Epub 2013 Sep 7.

Center for Global Health, Division of Infectious Diseases, Weill Cornell Medical College, New York, NY, United States of America.

Multidrug-resistant tuberculosis (MDR-TB) is an emerging problem in many parts of the world, and levels of MDR-TB among new TB patients are increasing in sub-Saharan Africa. We reviewed the prevalence and molecular epidemiology of MDR-TB in East Africa, including Burundi, Kenya, Rwanda, Tanzania, and Uganda. In 16 epidemiologic surveys, the prevalence of MDR among new cases ranges from 0.4% in Tanzania to 4.4% in Uganda, and among recurrent cases ranges from 3.9% in Tanzania to 17.7% in Uganda. There is a gap of 5948 cases between the estimated number of MDR-TB cases in East Africa and the number actually diagnosed. The only confirmed risk factors for MDR-TB are prior treatment for TB and refugee status. HIV has not been reported as a risk factor, and there are no reports of statistical association between spoligotype and drug resistance pattern. Increased capacity for diagnosis and treatment of MDR-TB is needed, with an emphasis on recurrent TB cases and refugees.
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http://dx.doi.org/10.1016/j.tube.2013.08.009DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3877177PMC
January 2014

Use of Luminex MagPlex magnetic microspheres for high-throughput spoligotyping of Mycobacterium tuberculosis isolates in Port-au-Prince, Haiti.

J Clin Microbiol 2013 Jul 8;51(7):2232-7. Epub 2013 May 8.

Center for Global Health, Division of Infectious Diseases, Department of Medicine, Weill Cornell Medical College, New York, New York, USA.

Genotyping of Mycobacterium tuberculosis strains became indispensable for understanding tuberculosis transmission dynamics and designing measures to combat the disease. Unfortunately, typing involves sophisticated laboratory analysis, is expensive, and requires a high level of technical expertise, which limited its use in the resource-poor countries where the majority of tuberculosis cases occur. Spoligotyping is a PCR-based M. tuberculosis complex genotyping method with advantages of technical simplicity, numerical output, and high reproducibility. It is based on the presence or absence of 43 distinct "spacers" separating insertion elements in the direct repeat region of the M. tuberculosis genome. The spoligotyping assay involves reverse hybridization of PCR products to the capture spacers attached to nitrocellulose membranes or to microspheres. Here we report modification of the classic 43-spacer method using the new generation of Luminex multiplexing technology with magnetic microspheres. The method was successfully established and validated on strains with known spoligotypes in our laboratory in Haiti. The distribution of spoligotypes determined in a collection of 758 recent M. tuberculosis isolates was in accordance with previous data for Haitian isolates in the SITWITWEB international database, which were obtained with the traditional membrane-based method. In the present form, spoligotyping may be suitable as a high-throughput, first-line tool for genotyping of Mycobacterium tuberculosis in countries with limited resources.
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http://dx.doi.org/10.1128/JCM.00268-13DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3697689PMC
July 2013

Efficacy of nitazoxanide against clinical isolates of Mycobacterium tuberculosis.

Antimicrob Agents Chemother 2013 Jun 18;57(6):2834-7. Epub 2013 Mar 18.

Center for Global Health, Department of Medicine, Weill Cornell Medical College, New York, New York, USA.

Nitazoxanide (NTZ) has bactericidal activity against the H37Rv laboratory strain of Mycobacterium tuberculosis with a MIC of 16 μg/ml. However, its efficacy against clinical isolates of M. tuberculosis has not been determined. We found that NTZ's MIC against 50 clinical isolates ranged from 12 to 28 μg/ml with a median of 16 μg/ml and was unaffected by resistance to first- or second-line antituberculosis drugs or a diversity of spoligotypes.
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http://dx.doi.org/10.1128/AAC.02542-12DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3716123PMC
June 2013

Multidrug-resistant tuberculosis in Port-au-Prince, Haiti.

Rev Panam Salud Publica 2012 Mar;31(3):221-4

Center for Global Health, Division of Infectious Diseases, Department of Medicine, Weill Cornell Medical College, New York, New York, United States of America.

Objective: To determine the prevalence of multidrug-resistant tuberculosis (MDR-TB) among patients with new smear-positive pulmonary TB in Port-au-Prince, Haiti.

Methods: Sputum samples were cultured from 1 006 patients newly diagnosed with TB in 2008. The core region of the rpoB gene that is associated with resistance to rifampin was sequenced. All isolates with rpoB mutations were sent to the New York State reference laboratory for conventional drug susceptibility testing (DST). All isolates were also tested with the GenoType MTBDRplus line-probe assay.

Results: Mycobacterium tuberculosis was isolated from 906 patients. Twenty-six (2.9%) of the isolates had missense mutations or deletions in rpoB and were resistant to rifampin by DST. All 26 were also resistant to isoniazid and classified as MDR-TB. Forty-six control isolates without rpoB mutations were found to be rifampin sensitive by DST. The GenoType MTBDRplus line-probe assay correctly identified 26 MDR-TB strains. It misclassified one pansusceptible isolate as rifampin resistant.

Conclusions: This study shows an MDR-TB prevalence of 2.9% in newly diagnosed TB patients in Haiti and suggests that rpoB sequencing and hybridization assays are good screening tools for early detection of MDR-TB.
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http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3676925PMC
http://dx.doi.org/10.1590/s1020-49892012000300006DOI Listing
March 2012

The effect of HIV and HPV coinfection on cervical COX-2 expression and systemic prostaglandin E2 levels.

Cancer Prev Res (Phila) 2012 Jan 1;5(1):34-40. Epub 2011 Dec 1.

Division of Infectious Diseases, Center for Global Health, Weill Cornell Medical College, 440 East 69 Street, New York, NY, USA.

Human immunodeficiency virus (HIV-1) infection causes chronic inflammation. COX-2-derived prostaglandin E(2) (PGE(2)) has been linked to both inflammation and carcinogenesis. We hypothesized that HIV-1 could induce COX-2 in cervical tissue and increase systemic PGE(2) levels and that these alterations could play a role in AIDS-related cervical cancer. Levels of cervical COX-2 mRNA and urinary PGE-M, a biomarker of systemic PGE(2) levels, were determined in 17 HIV-negative women with a negative cervical human papilloma virus (HPV) test, 18 HIV-infected women with a negative HPV test, and 13 HIV-infected women with cervical HPV and high-grade squamous intraepithelial lesions on cytology. Cervical COX-2 levels were significantly associated with HIV and HPV status (P = 0.006 and 0.002, respectively). Median levels of urinary PGE-M were increased in HIV-infected compared with uninfected women (11.2 vs. 6.8 ng/mg creatinine, P = 0.02). Among HIV-infected women, urinary PGE-M levels were positively correlated with plasma HIV-1 RNA levels (P = 0.003). Finally, levels of cervical COX-2 correlated with urinary PGE-M levels (P = 0.005). This study shows that HIV-1 infection is associated with increased cervical COX-2 and elevated systemic PGE(2) levels. Drugs that inhibit the synthesis of PGE(2) may prove useful in reducing the risk of cervical cancer or systemic inflammation in HIV-infected women.
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http://dx.doi.org/10.1158/1940-6207.CAPR-11-0496DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3252428PMC
January 2012

Adenovirus induction of IRF3 occurs through a binary trigger targeting Jun N-terminal kinase and TBK1 kinase cascades and type I interferon autocrine signaling.

J Virol 2009 May 11;83(9):4081-91. Epub 2009 Feb 11.

Department of Medicine, Weill Medical College, Cornell University, New York, New York 10021, USA.

Pathogen recognition is a critical function of immune sentinel cells. Naïve macrophages or dendritic cells (DCs) undergo pathogen-directed activation and maturation, and as mature antigen-presenting cells (APCs), they contribute essential functions to both innate and adaptive immunity. Using recombinant adenovirus (rAdV) as a model for murine APC activation by DNA viruses, we demonstrate a critical role for stress kinase activation in cell intrinsic and extrinsic antiviral signaling cascades. We propose two viral triggers, viral capsid and viral DNA, are required for APC activation. Endosomal escape and presentation of cytosolic rAdV DNA induces phosphorylation of TANK-binding kinase 1 (TBK1) at serine 172 but does not induce IkappaB kinase epsilon activity as determined by in vitro kinase assays. However, induction of TBK1 alone is not sufficient for interferon regulatory factor 3 (IRF3) phosphorylation. We show that capsid-dependent activation of Jun N-terminal kinase (JNK) stress kinase is a necessary step, licensing TBK1 phosphorylation of IRF3 at Ser 396. A second later phase of JNK activity is required to coordinate phosphorylation of JNK-dependent transcription factors (c-Jun/ATF2) with activated IRF3 in the induction of primary IRF3-responsive transcripts. Finally, we demonstrate that maximal JNK/TBK1/IRF3 stimulation by rAdV depends on an intact type I interferon (IFN) signaling cascade. By requiring multiple viral triggers and type I IFN autocrine regulation, APCs have an inherent fail-safe mechanism against inappropriate activation and maturation.
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http://dx.doi.org/10.1128/JVI.02591-08DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2668477PMC
May 2009

Sensing infection by adenovirus: Toll-like receptor-independent viral DNA recognition signals activation of the interferon regulatory factor 3 master regulator.

J Virol 2007 Apr 24;81(8):4145-57. Epub 2007 Jan 24.

Weill Medical College of Cornell University, Department of Microbiology and Immunology Box 62, 1300 York Ave. New York, NY 10021, USA.

Infection with adenovirus vectors (AdV) results in rapid activation of innate immunity, which serves the dual purpose of stimulating inflammatory antiviral host defenses and the adaptive immune system. Viral recognition by macrophages, dendritic cells, and other cell types requires an ability to sense the presence of a foreign molecular pattern by "pattern recognition receptors." The nature of the adenoviral sensor, the target ligand of the sensor, and the downstream antiviral signaling response triggered by virus infection have not been defined for this nonenveloped double-stranded DNA (dsDNA) virus. We have identified four critical links involved in AdV recognition by murine antigen-presenting cells (APC) and primary lung fibroblasts: (i) viral recognition occurs chiefly via a Toll-like receptor (TLR)-independent nucleic acid-sensing mechanism recognizing the viral dsDNA genome, (ii) the intact viral particle and capsid proteins are required for efficient intracellular delivery of the viral genome, (iii) delivery of the viral genome triggers interferon regulatory factor 3 (IRF3) phosphorylation, and (iv) IRF3 activation is the required dominant antiviral signaling pathway used by APC, whereas the "primary" involvement of NF-kappaB, mitogen-activated protein kinase, or Akt pathways is less prominent. In this study we provide the first direct evidence that infection by a dsDNA virus stimulates an IRF3-mediated interferon and proinflammatory response through a TLR-independent DNA-sensing mechanism.
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http://dx.doi.org/10.1128/JVI.02685-06DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC1866159PMC
April 2007