# Bacterial co-occurrence with pulmonary TB, a respiratory tract infection (RTI): A cross-sectional study in a resource-limited setting

## TL;DR

This study found that many TB patients in a rural South African region also had bacterial co-infections, which could complicate treatment and outcomes.

## Contribution

The study provides new insights into bacterial co-infections among TB patients in a resource-limited setting, highlighting socio-demographic risk factors.

## Key findings

- Non-tuberculous mycobacteria (NTM) were detected in 67% of TB patients.
- HIV-positive individuals had a higher prevalence of Aeromonas spp. and NTM co-infections.
- Age and socioeconomic status were significantly associated with TB and co-infection outcomes.

## Abstract

Bacterial co-infections significantly affect the treatment outcomes of tuberculosis (TB) patients, particularly in resource-limited settings. Misdiagnosis of TB co-infections accelerate disease progression and contribute to the development of drug resistance, leading to higher mortality and morbidity rates, especially in underserved areas. This study aimed to investigate bacterial co-infections in patients with pulmonary tuberculosis in a rural Vhembe region of Limpopo, South Africa.

A total of 100 sputum together with 100 blood samples were collected from TB patients who were undergoing TB treatment. DNA isolates were used as templates for PCR using the Anyplex™MTB/NTMe Assay kit, and subsequently, the Allplex™ MTB/MDR/XDRe Assay kit was used for the multiple detections of Mycobacterium tuberculosis (MTB) and resistance to first line and second line anti-TB drugs. Co-infections were determined using the Allplex™ Bacteria(I) & (II) Assay kit. HIV status of patients was determined using blood testing kits.

Majority of study participants were male (55 %) and aged between 36 and 55 (54 %), while female were 46 % of the population. Bacterial species detected included non-tuberculous mycobacteria (NTM) in 67 % of participants, Aeromonas spp. (19 %), Vibrio spp. (2 %), and E. coli (2 %). Multidrug-resistant Mycobacterium tuberculosis (MTB) strains were identified in 2 % of the cohort. There was a significant association between employment status and age (p = 0.00), as well as between HIV status and age (p = 0.03). While no significant associations were found between HIV status and the presence of NTM or other bacterial co-infections (p = 0.19 and 0.21, respectively), the majority of Aeromonas spp. and NTM cases were observed among HIV-positive participants. Notably, 36 of the NTM cases occurred in individuals living with HIV.

The study findings suggest that age, socioeconomic status, and gender play a role in the development of TB, HIV, and other bacterial infections, which could further complicate treatment outcomes in patients. These factors likely contribute to increased vulnerability to co-infections, emphasizing the complex interplay between TB and HIV in these populations. Additionally, the study emphasises the importance of considering these socio-demographic factors in public health interventions to reduce the burden of TB-HIV co-infection and associated bacterial infections.