Retrospective analysis of patients with non-tuberculous mycobacteria from a primary hospital in Southeast China

Abstract

to achieve a comprehensive understanding of the characteristics of patients with non-tuberculous mycobacteria (NTM), patients with NTM between January 2016 and June 2019 were recruited from a primary hospital. NTM were identified based on the MBP64 protein assay. The clinical records and laboratory assay results were retrospectively reviewed. A total of 204 patients with NTM were included in the final analysis. The patients with multiple isolations were more likely accompanied with chronic obstructive pulmonary disease (copD) (p = 0.029) and arthritis (p = 0.049), but showed a lower percentage of positive t-spot results (p = 0.022). In addition, patients with multiple isolations showed a higher rate of positive acid-fast staining results and their symptom duration was more likely longer than 30 days (p = 0.019). Patients with a positive response in T-spot assay showed a higher proportion of nodular manifestation on computed tomography (ct) than those with a negative response. compared with male patients with ntM, female patients showed lower rates of positive acid-fast staining results (p = 0.03), but were more likely accompanied with COPD (p < 0.0001). The positive acid-fast staining results were closely associated with pulmonary cavities and tuberculosis antibody. patients with different NTM isolation frequencies were closely associated with coexisting diseases and examination results.

Different source of sample strains corresponds to different characteristics of patients with non-tuberculous mycobacterium

“…Among patients with NTM in this study, the patients with COPD were mainly older and males, as it was also previously reported [11]. Limited data are available regarding the in uence of NTM infection on COPD, but our previous work and another study suggested that repeated isolation of samples in patients was associated with a higher percentage of COPD [10,11]. In a follow up study, COPD patients with NTM-positive sample more likely experience exacerbation than those with NTM-negative samples, and patients with multiple positive samples had a more pronounced pulmonary function decline than those with single or no positive samples [22].…”

“…The percentage of tuberculosis history between patients with COPD or without COPD was not signi cantly different, suggesting that previous tuberculosis infection might not be associated with the pathogenesis of COPD. Previous works showed that the percentage of patients with bronchiectasis presenting multiple NTM positive isolations is comparable to the percentage of patients with bronchiectasis presenting a single NTM positive isolation [10,11], indicating the limited impact of NTM infection on bronchiectasis. Instead, repeated isolations of NTM positive strains partly contributes to the progression of COPD [10,11].…”

“…Nodular-related bronchiectasis is of signi cance in the diagnosis and treatment of pulmonary NTM infection. Although bronchiectasis has been observed in 20%-30% of patients with NTM, NTM infection seems not common in patients with bronchiectasis [10,27]. Indeed, 34%-50% of patients with multiple small nodules (and sometimes cavity or cavities) combined with their diffusion (or widespread) indicate the presence of active pulmonary NTM infection [28].…”

“…The clinical records of inpatients and the corresponding NTM isolates were collected as previously described and anonymously reviewed [10]. The term "NTM isolates" is referred only to positive NTM isolates due to the aim of this work.…”

“…Previous studies showed that the repeated collection and isolation of NTM strains from patients was closely associated with a higher percentage of COPD when compared to the percentage revealed by a single isolation [10,11]. However, both studies above did not evaluate the correspondence of different source of the sample with different characteristics of both NTM disease and infected patients.…”