Characterization of clinical isolates of Mycobacterium tuberculosis from indigenous peoples of Colombia

Abstract

Introduction: Tuberculosis continues to be a public health priority. Indigenous peoples are vulnerable groups with cultural determinants that increase the risk of the disease. Objective: To determine molecular epidemiology features and phenotypically of Mycobacterium tuberculosis isolates in indigenous people in Colombia from 2009 to 2014. Materials and methods: Analytical observational study; 234 isolates were analyzed to determine their patterns of sensitivity to antituberculosis drugs and their molecular structures using the spoligotyping. Results: The isolates came from 41 indigenous groups, predominately the Wayúu (13.10%) and Emberá Chamí (11.35%). We found 102 spoligotypes that were distributed among seven genetic families (37.2% LAM, 15.8% Haarlem, 8.1% T, 3.4% U, 2.6% S, 2.1% X, and 0.9% Beijing). The association analysis showed that the non-clustered isolates were related to prior treatment, relapse, orphan spoligotypes and the Beijing family. The H family presented an association with the Arhuaco and Camëntŝá indigenous groups, the U family was associated with the Wounaan group, and the T family was associated with the Motilon Barí group. Conclusions: This is a first national study for characterization of M. tuberculosis of indigenous groups, this work evidenced that the diagnosis in the indigenous is late. We describe 53% of orphan patterns that could be typical of the Colombian indigenous population. The high percentage of grouping by spoligotyping (62%) could indicate cases of active transmission, a situation that should be corroborated using a second genotyping marker. A new Beijing spoligotype (Beijing-like SIT 406) was identified in Colombia.