RESUMEN
BACKGROUND & OBJECTIVES: There is a paucity of data available on genetic biodiversity of Mycobacterium tuberculosis isolates from central India. The present study was carried out on isolates of M. tuberculosis cultured from diagnostic clinical samples of patients from Bhopal, central India, using spoligotyping as a method of molecular typing. METHODS: DNA was extracted from 340 isolates of M. tuberculosis from culture, confirmed as M. tuberculosis by molecular and biochemical methods and subjected to spoligotyping. The results were compared with the international SITVIT2 database. RESULTS: Sixty five different spoligo international type (SIT) patterns were observed. A total of 239 (70.3%) isolates could be clustered into 25 SITs. The Central Asian (CAS) and East African Indian (EAI) families were found to be the two major circulating families in this region. SIT26/CAS1_DEL was identified as the most predominant type, followed by SIT11/EAI3_IND and SIT288/CAS[2]. Forty (11.8%) unique (non-clustered) and 61 (17.9%) orphan isolates were identified in the study. There was no significant association of clustering with clinical and demographic characteristics of patients. INTERPRETATION & CONCLUSIONS: Well established SITs were found to be predominant in our study. SIT26/CAS1_DEL was the most predominant type. However, the occurrence of a substantial number of orphan isolates may indicate the presence of active spatial and temporal evolutionary dynamics within the isolates of M. tuberculosis.
Asunto(s)
Variación Genética , Mycobacterium tuberculosis/genética , Tuberculosis/microbiología , Adolescente , Técnicas de Tipificación Bacteriana , Niño , Femenino , Genotipo , Humanos , India , Masculino , Persona de Mediana Edad , Repeticiones de Minisatélite/genética , Mycobacterium tuberculosis/clasificación , Mycobacterium tuberculosis/patogenicidad , Tuberculosis/genética , Adulto JovenRESUMEN
In India, extrapulmonary tuberculosis (EPTB) accounts for 10 - 15% of all types of tuberculosis. To identify and compare predominant spoligotypes and drug-resistance patterns in strains of Mycobacterium tuberculosis isolated from extrapulmonary and pulmonary specimens in central India, drug susceptibility testing and spoligotyping were carried out. Spoligotyping data was analyzed using SITVIT2 database. ST11/EAI3_Ind with 33% isolates among extrapulmonary specimens and ST26/CAS1_DEL with 28% isolates among pulmonary specimens were the most predominant lineages. Multidrug resistance was found in 5.5% of the strains isolated from extrapulmonary specimens in contrast to 17% isolated from pulmonary specimens.
Asunto(s)
Antituberculosos/farmacología , Farmacorresistencia Bacteriana , Variación Genética , Mycobacterium tuberculosis/clasificación , Mycobacterium tuberculosis/efectos de los fármacos , Tuberculosis/microbiología , Adulto , Anciano , Análisis por Conglomerados , Femenino , Genotipo , Humanos , India , Masculino , Pruebas de Sensibilidad Microbiana , Persona de Mediana Edad , Tipificación Molecular , Mycobacterium tuberculosis/genética , Mycobacterium tuberculosis/aislamiento & purificación , Adulto JovenRESUMEN
This cross-sectional multi-centric study compared the yield of and potential benefit for detecting smear-positive pulmonary tuberculosis (PTB) by bleach sedimentation (2% sodium-hypochlorite) versus direct microscopy under programme conditions in India. Among 3168 PTB suspects, 684 (21.6%) were detected by bleach sedimentation vs. 625 (19.7%) by direct microscopy, with a proportional overall agreement of 96% (κ = 0.88). While 594 patients were smear-positive with both methods, 31 patients detected by direct microscopy were missed and an additional 90 patients were detected by bleach sedimentation. Overall, bleach sedimentation increased the yield of smear-positive TB detection; however; it also increased the time to results.
Cette étude transversale multicentrique a comparé, dans les conditions du programme en Inde, le rendement et les avantages potentiels de la détection des tuberculoses pulmonaires (TBP) à frottis positif par la sédimentation à l'eau de Javel (2% d'hypochlorite de sodium) par comparaison avec l'examen microscopique direct. Parmi 3168 sujets suspects de TBP, 684 (21,6%) ont été détectés par la sédimentation à l'eau de Javel par rapport à 625 (19,7%) par l'examen microscopique direct, avec donc une proportion de 96% de concordance globale (κ = 0,88). Alors que les résultats des frottis étaient positifs chez 594 patients par les deux méthodes, l'examen microscopique direct a raté la détection chez 31 patients et la sédimentation à l'eau de Javel a détecté 90 patients de plus. Au total, la sédimentation à l'eau de Javel a augmenté le rendement de la détection des TB à frottis positif, mais a prolongé la durée avant obtention des résultats.
En un estudio transversal multicéntrico se comparó el rendimiento y la posible utilidad de la detección de la tuberculosis (TB) con baciloscopia positiva mediante la concentración del esputo con hipoclorito de sodio (2%) y se comparó esta técnica con el examen microscópico directo, en las condiciones del programa nacional de la India. En los 3168 pacientes con presunción clínica de TB se detectaron 684 casos (21,6%) por el método de la sedimentación con lejía y 625 casos (19,7%) mediante la microscopia directa, lo cual ofrece una concordancia global del 96% (índice κ = 0,88). Quinientos noventa y cuatro pacientes presentaron baciloscopias positivas con ambas técnicas; con la técnica de sedimentación se pasaron por alto 31 de los pacientes diagnosticados por microscopia directa y la concentración con lejía permitió el diagnóstico de 90 pacientes suplementarios. En términos generales, la sedimentación con lejía aumentó el rendimiento de la detección de casos de tuberculosis con baciloscopia positiva, pero prolongó el lapso hasta la obtención de los resultados.