Clinical aspects in patients with pulmonary infection caused by mycobacteria of the Mycobacterium abscessus complex, in the Brazilian Amazon

Abstract

Objective:To describe the clinical manifestations of patients with pulmonary infection caused by mycobacteria of the Mycobacterium abscessus complex (MABSC), and to compare these manifestations with those of patients infected with other nontuberculous mycobacteria (NTM). Methods:This was a retrospective cohort study involving 43 patients divided into two groups: the MABSC group, consisting of patients with pulmonary infection caused by MABSC (n = 17); and the NTM group, consisting of patients with pulmonary infection caused by NTM other than MABSC (n = 26). Patients were previously treated with a regimen of rifampin, isoniazid, pyrazinamide, and ethambutol before the diagnosis of NTM was confirmed by two culture-positive sputum samples. The nucleotide sequences of the hsp65, 16S rRNA, and/or rpoB genes were analyzed to identify the mycobacteria. Data were collected on demographic, clinical, and radiological characteristics, as well as on treatment responses and outcomes. Results:Loss of appetite was the only clinical manifestation that was significantly more common in the MABSC group than in the NTM group (p = 0.0306). The chance of having to use a second treatment regimen was almost 12 times higher in the MABSC group than in the NTM group. Treatment success was significantly higher in the NTM group than in the MABSC group (83.2% vs. 17.6%; p < 0.0001). The chance of recurrence was approximately 37 times higher in the MABSC group than in the NTM group. Conclusions:In the study sample, treatment response of pulmonary disease caused by MABSC was less favorable than that of pulmonary disease caused by other NTM.

Clinical aspects of the Mycobacterium abscessus complex

“…2 , 3 The failure of treatment is usually related to late diagnosis and previous antibiotic treatment due to the lack of standard microbiological testing to confirm the specificity of the pathogen. This situation seems to be similar to that reported by Monteiro et al 1 ; most of the patients receive antibiotic treatment before having the final diagnosis of MABSC. In addition, the availability of drugs of choice against MABSC (such as imipenem) is limited in large tertiary hospitals that cannot correspond to the increased incidence of the problem in a community hospital.…”

“…The study by Monteiro et al 1 on clinical aspects in patients with pulmonary infection caused by mycobacteria of the Mycobacterium abscessus complex (MABSC) in the Brazilian Amazon is very interesting. The authors concluded that the “treatment response of pulmonary disease caused by MABSC was less favorable than that of pulmonary disease caused by other nontuberculous mycobacteria .…”

“…Initially, on behalf of our team, I would like to thank the authors for their correspondence, aimed at the exchange of ideas about a complex clinical condition. The challenge of treating respiratory infection with mycobacteria of the Mycobacterium abscessus complex is established from the outset, either by the difficulty of isolating and identifying the bacteria, or by the fact that the patients are critically ill, typically developing structural lung changes prior to becoming ill. 1 …”

“…The abovementioned wide variety of drugs compose the therapeutic arsenal available for use, which is nevertheless of limited efficacy because of the bacterial resistance of the M. abscessus complex, mainly to macrolides and aminoglycosides. This excessive number of drugs creates barriers to a satisfactory clinical outcome, 1 the main barriers being the prolonged duration of treatment, which makes adherence difficult; the high incidence of adverse effects; the long hospital stay (due to parenteral administration of drugs); and the high economic cost.…”

Non-tuberculous mycobacterial lung disease: a brief review focusing on radiological findings

“…In Brazil, a study on clinical aspects of patients with LD by MABSC identified the presence of nodular bronchiectasis in individuals diagnosed with NTM infection but were not undergoing any treatment. However, these results are not sufficient to determine a radiological standard for NTM-LD findings 43 .…”