Preliminary survey of antimicrobial susceptibility and genetic variability of Mycobacterium tuberculosis isolates from Colombian Caribbean.

Abstract

Objective: The aim of this preliminary study was to investigate the drug susceptibility and genetic variability of Mycobacterium tuberculosis isolated from patients of Montería.

Methods: Patients with tuberculosis were included in the study. Socio-demographics and epidemiologic information was collected from each patient. Sputum samples were cultured on Lowenstein-Jensen medium. Antibiotic susceptibility testing was performed using the proportion method and rifoligotyping. The study of genetic variability was performed by RFLP.

Results: 67 strains of M. tuberculosis isolated from patients with pulmonary tuberculosis were included; fifty-nine patients (88%) were smear positive, the patients ranged from 14 to 83 of age, mean 41.5 years. The initial resistance and multidrug-resistance was 29.2% (14/48) and 6.7% (3/48) respectively. The rifoligotyping detected 4 strains (4, 17, 21 and 45) with the mutation in the rpoB gen, hot spot region codon 531. The number of IS6110-bands varied from 3 to 13, 12 (48%) isolates had among 8 and 9 copies. RFLP revealed genetic diversity of isolates in 2 groups: group A and B. Group A included 20 (80%) strains and only one cluster constituted by the patients 17, 45, 54. Group B, had 5 (20%) strains with only one cluster conformed by two patients 31 and 32.

Conclusions: The study demonstrated high levels of drug resistance and variability of strains of M. tuberculosis in Montería. Our results suggest establishing urgent measures of surveillance in epidemiology and public health for the control of the disease.