Aetiology of Pulmonary Symptoms in HIV-Infected Smear Negative Recurrent PTB Suspects in Kampala, Uganda: A Cross-Sectional Study

INTRODUCTION: Previously treated TB patients with pulmonary symptoms are often considered recurrent TB suspects in the resource-limited settings, where investigations are limited to microscopy and chest x-ray. Category II anti-TB drugs may be inappropriate and may expose patients to pill burden, drug toxicities and drug-drug interactions. OBJECTIVE: To determine the causes of pulmonary symptoms in HIV-infected smear negative recurrent pulmonary tuberculosis suspects at Mulago Hospital, Kampala. METHODS: Between March 2008 and December 2011, induced sputum samples of 178 consented HIV-infected smear negative recurrent TB suspects in Kampala were subjected to MGIT and LJ cultures for mycobacteria at TB Reference Laboratory, Kampala. Processed sputum samples were also tested by PCR to detect 18S rRNA gene of P.jirovecii and cultured for other bacteria. RESULTS: Bacteria, M. tuberculosis and Pneumocystis jirovecii were detected in 27%, 18% and 6.7% of patients respectively and 53.4% of the specimens had no microorganisms. S. pneumoniae, M. catarrhalis and H. influenzae were 100% susceptible to chloramphenicol and erythromycin but co-trimoxazole resistant. CONCLUSION: At least 81.5% of participants had no microbiologically-confirmed TB. However our findings call for thorough investigation of HIV-infected smear negative recurrent TB suspects to guide cost effective treatment.