Occurrence of nontuberculous mycobacterial pulmonary infection in an endemic area of tuberculosis

Abstract

The majority of investigations of the epidemiology of nontuberculous mycobacteria (NTM) have focused on highly developed nations with a low prevalence of tuberculosis. In contrast, the Para state of north Brazil represents an area of high tuberculosis prevalence and increasing NTM incidence. Toward the goal of understanding the dynamics of infection by all Mycobacterium species, we report patient characteristics and the identification of NTM strains isolated from sputum samples from patients that were residents of Para, a state in the Amazon region, Northern of Brazil, over the period January 2010 through December 2011 (2 years). The 29 NTM patients comprised 13.5% of positive mycobacterial cultures over the 2-year period. A major risk factor for NTM pulmonary disease was previous tuberculosis (76%). Further, the average age of NTM patients (52 years) was significantly higher than that of tuberculosis patients (39 years) and more were female (72.4% vs. 37.4%). Unlike other Brazilian states, NTM pulmonary patients in Para were infected with a different spectrum of mycobacteria; primarily the rapidly growing Mycobacterium massiliense and Mycobacterium simiae complex.

Figure 1. Proportion of tuberculosis and nontuberculous mycobacterial lung disease by age group - State of Para, Brazil, 2010–2011.

Figure 2. Representative image showing lung damage in a patient with nontuberculous mycobacterial diseases.

A 69-years-old woman with Mycobacterium abscessus pulmonary disease. (A and B) High resolution computed tomography (HRCT) of the chest obtained at level of upper lobes showing multiples cavities in the right upper lobe and centrilobular nodules. It is also possible to observe bronchiectasis in left upper lobe (arrow). (C) Tree-in-bud pattern. (D) Presence of bronchiectasis in middle lobe. Also note centrilobular nodules at right lower lobe.