Chronic Granulomatous Disease (CGD): Commonly Associated Pathogens, Diagnosis and Treatment.

Chronic granulomatous disease (CGD) is a primary immunodeficiency caused by a defect in the phagocytic function of the innate immune system owing to mutations in genes encoding the five subunits of the nicotinamide adenine dinucleotide phosphatase (NADPH) oxidase enzyme complex. This review aimed to provide a comprehensive approach to the pathogens associated with chronic granulomatous disease (CGD) and its management. Patients with CGD, often children, have recurrent life-threatening infections and may develop infectious or inflammatory complications. The most common microorganisms observed in the patients with CGD are Staphylococcus aureus, Aspergillus spp., Candida spp., Nocardia spp., Burkholderia spp., Serratia spp., and Salmonella spp. Antibacterial prophylaxis with trimethoprim-sulfamethoxazole, antifungal prophylaxis usually with itraconazole, and interferon gamma immunotherapy have been successfully used in reducing infection in CGD. Haematopoietic stem cell transplantation (HCT) have been successfully proven to be the treatment of choice in patients with CGD.

Severe Combined Immunodeficiency-Classification, Microbiology Association and Treatment.

Severe combined immunodeficiency (SCID) is a primary inherited immunodeficiency disease that presents before the age of three months and can be fatal. It is usually due to opportunistic infections caused by bacteria, viruses, fungi, and protozoa resulting in a decrease in number and impairment in the function of T and B cells. Autosomal, X-linked, and sporadic forms exist. Evidence of recurrent opportunistic infections and lymphopenia very early in life should prompt immunological investigation and suspicion of this rare disorder. Adequate stem cell transplantation is the treatment of choice. This review aimed to provide a comprehensive approach to the microorganisms associated with severe combined immunodeficiency (SCID) and its management. We describe SCID as a syndrome and summarize the different microorganisms that affect children and how they can be investigated and treated.

Clonal Complexes Distribution of Staphylococcus aureus Isolates from Clinical Samples from the Caribbean Islands.

The aim of this study was to comprehensively characterise S. aureus from the Caribbean Islands of Trinidad and Tobago, and Jamaica. A total of 101 S. aureus/argenteus isolates were collected in 2020, mainly from patients with skin and soft tissue infections. They were characterised by DNA microarray allowing the detection of ca. 170 target genes and assignment to clonal complexes (CC)s and strains. In addition, the in vitro production of Panton-Valentine leukocidin (PVL) was examined by an experimental lateral flow assay. Two isolates were identified as S. argenteus, CC2596. The remaining S. aureus isolates were assigned to 21 CCs. The PVL rate among methicillin-susceptible S. aureus (MSSA) isolates was high (38/101), and 37 of the 38 genotypically positive isolates also yielded positive lateral flow results. The isolate that did not produce PVL was genome-sequenced, and it was shown to have a frameshift mutation in agrC. The high rate of PVL genes can be attributed to the presence of a known local CC8-MSSA clone in Trinidad and Tobago (n = 12) and to CC152-MSSA (n = 15). In contrast to earlier surveys, the USA300 clone was not found, although one MSSA isolate carried the ACME element, probably being a mecA-deficient derivative of this strain. Ten isolates, all from Trinidad and Tobago, were identified as MRSA. The pandemic ST239-MRSA-III strain was still common (n = 7), but five isolates showed a composite SCCmec element not observed elsewhere. Three isolates were sequenced. That showed a group of genes (among others, speG, crzC, and ccrA/B-4) to be linked to its SCC element, as previously found in some CC5- and CC8-MRSA, as well as in S. epidermidis. The other three MRSA belonged to CC22, CC72, and CC88, indicating epidemiological connections to Africa and the Middle East.

Colonization of Streptococcus agalactiae among pregnant patients in Trinidad and Tobago.

Objective: To assess colonization of Streptococcus agalactiae [group B streptococcus (GBS)], and delineate capsular serotype distribution and antibiotic susceptibility profiles among pregnant women in Trinidad and Tobago. Methods: Vaginal swabs were collected from 248 pregnant women attending antenatal clinics in northern Trinidad, and processed using standard microbiological laboratory tests to confirm GBS. Polymerase chain reaction detected atr and cps serotype genes. Antimicrobial susceptibility tests were performed using the Kirby-Bauer method, and SPSS Version 25 was used for statistical analysis. Prevalence ratio measured the risk, and P≤0.05 was considered to indicate significance. Results: The GBS carriage rate was 29% (72/248, 95% confidence interval 23.3-34.8), and carriage was significantly associated with variables including gestational diabetes (P=0.042), age 25-35 years (P=0.006), multiparity (P=0.035) and marital status (P=0.006). The most common serotype was type II [47.2% (34/72)], and serotypes V, VI, VII and VIII were not encountered. GBS showed high resistance to amoxicillin-clavulanic acid (37.5%), erythromycin (30.6%), trimethoprim-sulphamethoxazole (58.3%) and tetracycline (97.2%). Conclusion: GBS colonization among pregnant women and resistance to commonly used antibiotics are high in Trinidad and Tobago. A population-based study is required to obtain accurate figures in order to improve maternal healthcare services.

Epidemiological evaluation of risk factors associated with vaginal candidiasis in a cross section of pregnant women in Trinidad and Tobago.

Vaginal Candidiasis and associated epidemiological risk factors prevalent among a cross section of pregnant women attending tertiary hospital in Trinidad and Tobago was evaluated. Standardized questionnaire was used to survey 492 pregnant women over a period of 10 months in 2019. Vaginal swab was collected and processed using standard microbiological laboratory methods for phenotypic identification. Data were analyzed using SPSS to identify potential risk factors. Chi-squared (ꭓ2) test and logistic regression tests examined associations and odds ratios with corresponding 95% confidence intervals. Prevalence of vulvovaginal candidiasis was 44.9% with Candida albicans as predominant species identified (62%, N=492). Vaginal candidiasis was statistically significant for several risk factors, including second trimester (p = 0.03), age group 26 - 34 years (p=003), history of masturbation especially during the last 48hours prior to the swabbing (p=0.05), and wearing of pants as opposed to skirt clothes (p=0.04). In conclusion, several epidemiological risk factors are associated vaginal candidiasis among cross section of pregnant women in the country. Patient education, microbiological investigations and appropriate treatment will improve antenatal healthcare delivery in the country.

Extended Spectrum Beta-Lactamase (ESBL) Produced by Gram-Negative Bacteria in Trinidad and Tobago.

Gram-negative bacterial infections are a global health problem. The production of beta-lactamase is still the most vital factor leading to beta-lactam resistance. In Trinidad and Tobago, extended spectrum beta-lactamase (ESBL) production has been detected and reported mainly in the isolates of Klebsiella pneumoniae and Escherichia coli and constitutes a public health emergency that causes high morbidity and mortality in some patients. In this literature review, the authors cover vast information on ESBL frequency and laboratory detection using both conventional and molecular methods from clinical data. The aim is to make the reader reflect on how the actual knowledge can be used for rapid detection and understanding of the spread of antimicrobial resistance problems stemming from ESBL production among common Gram-negative organisms in the health care system.

Origin, evolution, and global transmission of community-acquired Staphylococcus aureus ST8.

USA300 is a pandemic clonal lineage of hypervirulent, community-acquired, methicillin-resistant Staphylococcus aureus (CA-MRSA) with specific molecular characteristics. Despite its high clinical relevance, the evolutionary origin of USA300 remained unclear. We used comparative genomics of 224 temporal and spatial diverse S. aureus isolates of multilocus sequence type (ST) 8 to reconstruct the molecular evolution and global dissemination of ST8, including USA300. Analyses of core SNP diversity and accessory genome variations showed that the ancestor of all ST8 S. aureus most likely emerged in Central Europe in the mid-19th century. From here, ST8 was exported to North America in the early 20th century and progressively acquired the USA300 characteristics Panton-Valentine leukocidin (PVL), SCCmec IVa, the arginine catabolic mobile element (ACME), and a specific mutation in capsular polysaccharide gene cap5E Although the PVL-encoding phage ϕSa2USA was introduced into the ST8 background only once, various SCCmec types were introduced to ST8 at different times and places. Starting from North America, USA300 spread globally, including Africa. African USA300 isolates have aberrant spa-types (t112, t121) and form a monophyletic group within the clade of North American USA300. Large parts of ST8 methicillin-susceptible S. aureus (MSSA) isolated in Africa represent a symplesiomorphic group of ST8 (i.e., a group representing the characteristics of the ancestor), which are rarely found in other world regions. Isolates previously discussed as USA300 ancestors, including USA500 and a "historic" CA-MRSA from Western Australia, were shown to be only distantly related to recent USA300 clones.

Genetic characteristics and molecular epidemiology of vancomycin-resistant Enterococci isolates from Caribbean countries.

Emergence of vancomycin-resistant Enterococci (VRE) that first appeared on the stage about three decades ago is now a major concern worldwide as it has globally reached every continent. Our aim was to simply undertake a multinational study to delineate the resistance and virulence genes of clinical isolates of VRE isolates from the Caribbean. We employed both conventional (standard microbiological methods including use of E-test strips, chromogenic agar) and molecular methods (polymerase chain reactions-PCR, pulsed-field gel electrophoresis-PFGE and multilocus sequence typing-MLST) to analyze and characterize 245 Enterococci species and 77 VRE isolates from twelve hospitals from eight countries in the Caribbean. The PCR confirmed and demonstrated the resistance and virulence genes (vanA and esp) among all confirmed VRE isolates. The PFGE delineated clonally related isolates from patients from the same country and other countries in the region. The main sequence types of the VRE isolates from the region included STs 412, 750, 203, 736 and 18, all from the common ancestor for clonal complex 17 (CC17). Despite this common ancestor and association of outbreaks of this lineage clones, there has been no reports of outbreaks of infection by VRE in several hospitals in the Caribbean.

Detection of a CTX-M group 2 beta-lactamase gene in a Klebsiella pneumoniae isolate from a tertiary care hospital, Trinidad and Tobago.

BACKGROUND: Identification of the prevalence and spread of ESBL-mediated antibiotic resistance is essential especially in the hospital setting. It is for this reason, more and more studies are highlighting the importance of complementing phenotypic ESBL-detection techniques with molecular techniques in order to understand the basis and extent of this form of resistance among clinically evolved bacterial populations, especially those belonging to the Enterobacteriaceae family. However, in Trinidad and Tobago and other Caribbean countries, very little is known regarding ESBL detection rates and/or the prevalence of genes conferring ESBL resistance. METHODOLOGY: Sixty-six Klebsiella pneumoniae isolates from clinical specimens phenotypically identified by the Microscan Walkaway-96 System as potential ESBL-producers were analysed in this study. Screening and confirmation of these isolates as ESBL producers was done by the Clinical and Laboratory Standards Institute (CLSI) approved methods. Polymerase chain reaction amplification of beta-lactamase genes bla TEM, bla SHV, bla CTX-M1, bla CTX-M2 and bla AmpC was performed to identify mechanisms of ß-lactam resistance. RESULTS: ESBL-producing K. pneumoniae was confirmed in 78.8% (41/52) from isolates collected from a variety of sources during the period, April-July 2015. bla SHV (84.8%) and bla CTX-M (46.9%) were the predominant ß-lactamase genes identified. A single K. pneumoniae isolate possessed a bla CTX-M group 2 beta-lactamase gene. RAPD analysis identified a number of epidemiologically related isolates. However, current isolates were unrelated to isolates from previous years. CONCLUSION: This study revealed that among K. pneumoniae isolates exhibiting extended spectrum ß-lactam resistance, there was a high prevalence of bla SHV and bla CTX-M genes. This result highlights the need for a reliable epidemiological apparatus that involves the molecular characterisation of ESBL resistance.

Molecular characterization of vancomycin-resistant Enterococcus faecium isolates from Bermuda.

Molecular characteristics of vancomycin resistant enterococci isolates from Bermuda Island is currently unknown. This study was conducted to investigate phenotypic and genotypic characteristics of VRE isolates from Bermuda Island using the chromogenic agar, E-tests, polymerase chain reaction (PCR), pulsed-field gel electrophoresis (PFGE) and multilocus sequence typing (MLST). Eighteen E. faecium isolates were completely analyzed and were all resistant to vancomycin, susceptible to linezolid and quinupristin/dalfopristin, positive for vanA and esp genes. The MLST analysis confirmed most isolates were of the sequence types linked to clonal complex 17 (CC17) that is widely associated with outbreaks in hospitals. Infection control measures, antibiotic stewardship, and surveillance activities will continue to be a priority in hospital on the Island.

Serotypes and genotypes of Streptococcus pneumoniae isolates from Trinidad and Tobago.

OBJECTIVES: There are currently 94 known pneumococcal capsular polysaccharide serotypes and their prevalence differs by geographic region and the period studied. Streptococcus pneumoniae infections have been diagnosed clinically in Trinidad and Tobago and other Caribbean countries, however data on the serotype and sequence type distributions in this country are limited. The objective of this study was to determine serotypes and multilocus sequence types (MLSTs) of invasive and non-invasive pneumococcal isolates from Trinidad and Tobago. METHODS: Ninety-eight pneumococcal isolates from several regional hospitals in the country were analyzed using both standard microbiological methods and molecular analysis. These isolates included invasive (n=83) and selected non-invasive (n=15) strains recovered before (n=25) and after (n=73) the introduction of the pneumococcal conjugate vaccine. RESULTS: More than half of the isolates (54.1%) were recovered from children under 15 years of age, with the largest proportion being from children under 2 years of age (24.5%). The most prevalent serotypes were 19F (18.4%), 6B (15.3%), 23F (14.3%), 3 (11.2%), 19A (6.1%), 6A (5.1%), 14 (5.1%), and 9V (4.1%). The most common serotype/MLST combinations were 6B/ST138 (n=10, 10.2%), 3/ST180 (n=5, 5.1%), 23F/ST629 (n=5, 5.1%), 19F/ST8398 (n=4, 4.1%), and three each of 6B/ST145, 14/9V/ST156, 9V/ST162, 19A/320, and 3/ST10440. CONCLUSIONS: This report provides the first glimpse of the prevailing pneumococcal sequence types in the country. Most of the isolates represented serotypes in the 10-valent (61.2% of isolates) and 13-valent (83.7%) pneumococcal conjugate vaccines. A detailed population study is warranted to fully determine the circulating pneumococcal sequence types. Furthermore, the implementation of an effective and continuous surveillance system in Trinidad and Tobago is paramount to monitor vaccine impact.

Population structure of Staphylococcus aureus from Trinidad & Tobago.

It has been shown previously that high rates of methicillin- and mupirocin-resistant Staphylococcus aureus exist in the Caribbean islands of Trinidad and Tobago, as well as a high prevalence of Panton-Valentine leukocidin-positive S. aureus. Beyond these studies, limited typing data have been published. In order to obtain insight into the population structure not only of MRSA but also of methicillin-susceptible S. aureus, 294 clinical isolates collected in 2012/2013 were typed by microarray hybridisation. A total of 15.31% of the tested isolates were MRSA and 50.00% were PVL-positive. The most common MSSA strains were PVL-positive CC8-MSSA (20.41% of all isolates tested), PVL-positive CC152-MSSA (9.52%) and PVL-positive CC30-MSSA (8.84%) while the most common MRSA were ST239-MRSA-III&SCCmer (9.18%) and ST8-MRSA-IV, "USA300" (5.78%). 2.38% of characterised isolates belonged to distinct strains likely to be related to "Staphylococcus argenteus" lineages. The population structure of S. aureus isolates suggests an importation of strains from Africa, endemicity of PVL-positive MSSA (mainly CC8) and of ST239-MRSA-III, and a recent emergence of the PVL-positive CC8-MRSA-IV strain "USA300".

Rapid detection of Panton-Valentine leukocidin in Staphylococcus aureus cultures by use of a lateral flow assay based on monoclonal antibodies.

Panton-Valentine leukocidin (PVL) is a virulence factor of Staphylococcus aureus, which is associated with skin and soft-tissue infections and necrotizing pneumonia. To develop a rapid phenotypic assay, recombinant PVL F component was used to generate monoclonal antibodies by phage display. These antibodies were spotted on protein microarrays and screened using different lukF-PV preparations and detection antibodies. This led to the identification of the optimal antibody combination that was then used to establish a lateral flow assay. This test was used to detect PVL in S. aureus cultures. The detection limit of the assay with purified native and recombinant antigens was determined to be around 1 ng/ml. Overnight cultures from various solid and liquid media proved suitable for PVL detection. Six hundred strains and clinical isolates from patients from America, Europe, Australia, Africa, and the Middle East were tested. Isolates were genotyped in parallel by DNA microarray hybridization for confirmation of PVL status and assignment to clonal complexes. The sensitivity, specificity, and positive and negative predictive values of the assay in this trial were 99.7, 98.3, 98.4, and 99.7%, respectively. A total of 302 clinical isolates and reference strains were PVL positive and were assigned to 21 different clonal complexes. In summary, the lateral flow test allows rapid and economical detection of PVL in a routine bacteriology laboratory. As the test utilizes cultures from standard media and does not require sophisticated equipment, it can be easily integrated into a laboratory's workflow and might contribute to timely therapy of PVL-associated infections.

Comparison of the QuantiFERON®-TB Gold assay and tuberculin skin test to detect latent tuberculosis infection among target groups in Trinidad & Tobago.

OBJECTIVE: To compare the QuantiFERON®-TB Gold (QFT-G) assay and tuberculin skin test (TST) in screening/diagnosis of latent tuberculosis infection (LTBI) among individuals in Trinidad & Tobago at high risk for TB. METHODS: A total of 560 individuals (TB patient contacts, HIV patients, health care workers, prison inmates, and TB patients [controls]) were recruited for the study. Blood was drawn and processed using the QFT-G assay, followed by immediate administration of TST solution on subjects' forearm. Data were analyzed with Epi InfoTM 3.5.1 software. Results were compared across the target groups using the chi-square test (P < 0.05). RESULTS: The QFT-G assay detected LTBI in 51% of the subjects (with most positive results occurring among the control group) whereas the TST detected it in 39.4% (P = 0.001). Overall, the QFT-G assay detected LTBI more frequently than the TST among all subjects except the control group, where detection favored the TST. The QFT-G assay produced indeterminate and nonreactive results in some HIV patients but required less turnaround time than the TST (23.3 h versus 70.2 h; P < 0.0001). The TST cost less per subject than the QFT-G assay (US $3.70 versus US $18.60; P = 0.0008). CONCLUSIONS: The QFT-G assay cost more but had a higher detection rate among most target groups and required less turnaround time than the TST. However, its sensitivity was lower among immunocompromised subjects. Therefore, the QFT-G assay should be used with caution for LBTI screening/diagnosis in resource-poor, high-HIV prevalence settings such as Trinidad & Tobago.

Comparison of the QuantiFERON®-TB Gold assay and tuberculin skin test to detect latent tuberculosis infection among target groups in Trinidad & Tobago / Comparación entre la prueba QuantiFERON®-TB Gold y la prueba cutánea de la tuberculina para detectar la infección tuberculosa latente en grupos destinatarios en Trinidad y Tabago

OBJECTIVE: To compare the QuantiFERON®-TB Gold (QFT-G) assay and tuberculin skin test (TST) in screening/diagnosis of latent tuberculosis infection (LTBI) among individuals in Trinidad & Tobago at high risk for TB. METHODS: A total of 560 individuals (TB patient contacts, HIV patients, health care workers, prison inmates, and TB patients [controls]) were recruited for the study. Blood was drawn and processed using the QFT-G assay, followed by immediate administration of TST solution on subjects' forearm. Data were analyzed with Epi InfoTM 3.5.1 software. Results were compared across the target groups using the chi-square test (P < 0.05). RESULTS: The QFT-G assay detected LTBI in 51 percent of the subjects (with most positive results occurring among the control group) whereas the TST detected it in 39.4 percent (P = 0.001). Overall, the QFT-G assay detected LTBI more frequently than the TST among all subjects except the control group, where detection favored the TST. The QFT-G assay produced indeterminate and nonreactive results in some HIV patients but required less turnaround time than the TST (23.3 h versus 70.2 h; P < 0.0001). The TST cost less per subject than the QFT-G assay (US $3.70 versus US $18.60; P = 0.0008). CONCLUSIONS: The QFT-G assay cost more but had a higher detection rate among most target groups and required less turnaround time than the TST. However, its sensitivity was lower among immunocompromised subjects. Therefore, the QFT-G assay should be used with caution for LBTI screening/diagnosis in resource-poor, high-HIV prevalence settings such as Trinidad & Tobago.

OBJETIVO: Comparar la prueba QuantiFERON®-TB Gold (QFT-G) con la prueba cutánea de la tuberculina (PPD) para el tamizaje y diagnóstico de la infección tuberculosa latente (ITBL) en personas con alto riesgo de tuberculosis en Trinidad y Tabago. MÉTODOS: Para el estudio, se reclutó un total de 560 individuos (personas en contacto con pacientes de tuberculosis, pacientes con VIH, trabajadores de la salud, presidiarios y pacientes de tuberculosis [grupo testigo]). Las muestras de sangre se extrajeron y procesaron utilizando la prueba QFT-G, seguida de la aplicación inmediata de la solución de PPD en el antebrazo de las personas. Los datos se analizaron con el software Epi InfoTM 3.5.1. Los resultados obtenidos en los grupos destinatarios se compararon utilizando la prueba de la ji al cuadrado (P < 0,05). RESULTADOS: La prueba QFT-G detectó la infección tuberculosa latente en 51 por ciento de los individuos (la mayoría de los resultados positivos se presentaron en el grupo testigo) mientras que la prueba PPD la detectó en 39,4 por ciento (P = 0,001). En términos generales, la prueba QFT-G detectó la infección tuberculosa latente con mayor frecuencia que la PPD en todos los individuos, excepto en aquellos del grupo testigo, donde el índice de detección favoreció a la PPD. La prueba QFT-G produjo resultados indeterminados y no reactivos en algunos pacientes con VIH, pero requirió menos tiempo de respuesta que la PPD (23,3 h contra 70,2 h; P < 0.0001). La prueba PPD tuvo un costo menor por individuo que la QFT-G (US$3,70 en comparación con US$18,60; P = 0.0008). CONCLUSIONES: La prueba QFT-G tuvo un costo más elevado, pero la tasa de detección fue más alta en la mayoría de los grupos destinatarios y el tiempo de respuesta fue más rápido en comparación con la PPD. Sin embargo, la sensibilidad de la prueba QFT-G fue inferior entre los individuos inmunodeficientes. Por consiguiente, se deben tomar las precauciones necesarias para utilizar la prueba QFT-G en el tamizaje y diagnóstico de ITBL en entornos de escasos recursos y alta prevalencia de VIH como Trinidad y Tabago.

Phylogeographical and molecular characterization of an emerging Mycobacterium tuberculosis clone in Trinidad and Tobago.

We report on a fine molecular and phylogenetical characterization of circulating Mycobacterium tuberculosis strains isolated from patients during a 1-year period in Trinidad and Tobago (T&T). The spoligotyping data coupled to minisatellite typing and available epidemiological data showed that a single major clone of "evolutionary modern" tubercle bacilli (SIT566) was responsible for more than half of the tuberculosis (TB) cases. It preferentially infected younger age groups (mean 39.1 years versus 47.7 years for other genotypes, p<0.0005), and was overrepresented in Port-of-Spain (1 out of 3 patients). A comparison of genotyping results to data gathered for 6 Caribbean countries (n=2653 clinical isolates) showed that the overall lineage distribution in T&T was completely different from its neighbors, e.g., T&T was the only country harboring a unique sublineage of the Latin American & Mediterranean (LAM) family, designated LAM-10CAM with phylogeographical specificity for Cameroon and neighboring countries in West Africa; interestingly 3/4 of the patients within this group in T&T were African descendants. Similarly, strains belonging to East African Indian (EAI) lineage with phylogeographical specificity for the Indian subcontinent, were found in T&T (13% of all strains), but were absent among the neighboring countries. Although the predominant SIT566 was not yet detected elsewhere in the Caribbean, available information underlined that this genotype was already present in the United States as imported cases of disease among T&T-born patients. Characterization of SIT566 strains using 12-, 15- and 24-loci MIRU typing, and comparison of results to international databases showed that these isolates were characterized by a common 12-loci MIRU pattern 224315153324 corresponding to MIRU International Type-MIT633 in 21/25 strains tested, as well as its 4 variants; an orphan pattern , MIT27-, MIT117-, and MIT1158-. Extended 24-loci MIRU typing led to a predominant pattern 224315153324323483334323 in a total of 16/21 MIT633 isolates, as well as identification of 3 supplemental patterns. Comparison of 24-loci MIRU data with the international database MIRU-VNTRplus showed the unique nature of the patterns obtained in T&T. Further analysis using the Levenshtein algorithm showed that the first 2 closest matches with the SIT566/MIT633 clone belonged to the X lineage strains in MIRU-VNTRplus. This observation corroborates our preliminary spoligotyping-based analysis using minimum spanning and neighbor-joining trees, which suggested a phylogenetical relatedness of the SIT566 clone with SIT119, which represents X1 lineage prototype in SpolDB4 database. We hypothesize that the predominant SIT566 clone might have evolved from a pool of X lineage M. tuberculosis strains with phylogeographical affinity for Anglo-Saxon descendants.

First insight into Mycobacterium tuberculosis epidemiology and genetic diversity in Trinidad and Tobago.

This report is based on a 1-year recruitment of all of the culture-positive Mycobacterium tuberculosis cases in Trinidad and Tobago (n = 132). The study population was characterized by a high male-to-female sex ratio of 4 and a human immunodeficiency virus-tuberculosis (TB) coinfection rate of 30 per cent. It mainly occurred among African descendants, who represent 37.5 per cent of the total population but 69.7 per cent of all TB cases (P < 0.001). Spoligotyping resulted in 25 different patterns and 12 clusters (2 to 74 strains per cluster), with the predominance of a highly conserved spoligotype international type clone, SIT566.

First insight into Mycobacterium tuberculosis epidemiology and genetic diversity in Trinidad and Tobago.

This report is based on a 1-year recruitment of all of the culture-positive Mycobacterium tuberculosis cases in Trinidad and Tobago (n = 132). The study population was characterized by a high male-to-female sex ratio of 4 and a human immunodeficiency virus-tuberculosis (TB) coinfection rate of 30%. It mainly occurred among African descendants, who represent 37.5% of the total population but 69.7% of all TB cases (P < 0.001). Spoligotyping resulted in 25 different patterns and 12 clusters (2 to 74 strains per cluster), with the predominance of a highly conserved spoligotype international type clone, SIT566.

Evaluation of methods for rapid detection of resistance to isoniazid and rifampin in Mycobacterium tuberculosis isolates collected in the Caribbean.

The rapid identification of drug-resistant strains of Mycobacterium tuberculosis is crucial for the timely initiation of appropriate antituberculosis therapy. The performance of the Genotype MTBDRplus assay was compared with that of the Bactec 460 TB system, a "gold standard" culture-based method. The Genotype MTBDRplus assay was quicker and more cost-effective for the detection of rifampin resistance, but it was not as good for the detection of isoniazid-resistant strains in our setting.