Impact of chronic co-infection in pulmonary Mycobacterium avium complex disease after treatment initiation

Abstract

Background The impact of co-infection with other pathogenic microorganisms after initiation of treatment for Mycobacterium avium complex pulmonary disease (MAC-PD) has not been clearly described. This study sought to clarify the clinical outcomes of co-infection with MAC after antimycobacterial therapy for MAC. Methods Co-infection status was defined as the detection of pathogenic microorganisms other than MAC in at least two consecutive sputum cultures 6–24 months after initiation of treatment. Chest computed tomography (CT) findings and culture results were compared between co-infection and MAC alone groups. Results The co-infection and MAC alone groups comprised 12 and 36 patients, respectively. The proportion of patients with sputum culture positive for MAC after 24 months of therapy did not differ significantly between the two groups [25% (3/12) vs. 16.7% (6/36); p = 0.671]. The proportion of patients with improved chest CT score after 24 months of starting treatment compared to baseline was significantly lower for the co-infection group than for the MAC alone group [16.7% (2/12) vs. 79.4% (27/34); p < 0.001]. In the co-infection group, median CT score values at 12 and 24 months did not differ from baseline. However, the MAC alone group showed significant improvement at 12 and 24 months compared with baseline. Conclusions In the patient group with co-infection of other pathogenic microorganisms after treatment initiation for MAC there was no impact on therapeutic efficacy compared to the MAC alone group. However, therapeutic intervention interfered with improvement in chest CT findings such as nodule formation, bronchiectasis, infiltration, and cavitary lesions.

Mycobacterium tuberculosis and Mycobacterium avium Coinfection in an Immunocompetent Patient

“…There was an increased prevalence of concurrent infection in those with chronic obstructive pulmonary disease (COPD) [ 8 ]. In a subsequent study, the coinfections were shown not to have any impact on the therapeutic efficacy of MAC [ 9 ]. Another study looked into the impact of concomitant infection by fungal species like Aspergillus fumigatus , Histoplasma capsulatum , and Cryptococcus neoformans .…”

Risk factors for clinical progression in patients with pulmonary Mycobacterium avium complex disease without culture-positive sputum: a single-center, retrospective study

“…However, neither the microbiological findings nor the bronchiectasis-predominant type in the present study affected disease status. This result may have been affected by the fact that patients with pulmonary MAC diagnosed by bronchoscopy had fewer cavities, less severe bronchiectasis, and less presence of locus minoris resistentiae [ 30 , 31 ]. On the other hand, Veillonella species, anaerobic bacteria, were detected in almost half of the pulmonary MAC patients in both groups.…”

Exploring the Association of Bacterial Coinfections with Clinical Characteristics of Patients with Nontuberculous Mycobacterial Pulmonary Disease

“…One of these manifestations is that the bronchi become more susceptible to chronic, slowly progressive inflammation, potentially compromising their structural integrity 6 . Furthermore, the compromised airways in NTM-PD patients are more susceptible to secondary infections, and previous studies have indicated that 12% -45% of patients with Mycobacterium avium complex pulmonary disease (MAC-PD) concurrently exhibit bacterial infections [7][8][9] . Although prior investigations have consistently identified co-infection with bacterial pathogens alongside NTM acquisition or disease course, these studies have been limited by the use of sputum culture-based bacterial detection, small numbers of patients, and differences in research objectives and testing timing depending on study design [7][8][9][10] .…”