BACKGROUND: In Maiduguri, Nigeria in the 1990's, we had available to us only the direct Acid Fast Bacilli (AFB) smear method to diagnose tuberculosis (TB), and no facility for TB culture. Because the clinical and radiologic manifestations of lower respiratory tract (LRT) fungal infections are difficult to differentiate from those of LRT TB, it was not clear how many of the direct AFB smear negative patients had fungal infections, or were true negatives for TB. OBJECTIVE: To assess sputum samples from patients with suspected lower respiratory tract infection for non-candidal fungal isolates as well as Mycobacterium tuberculosis. METHODS: Smears of sputum samples were examined microscopically for fungal hyphae and AFB. Sputum samples were also plated onto different fungal culture media. Isolation data were correlated with clinical and radiological data, to determine their clinical significance. RESULTS: Of the 274 patients seen, 41(15%) had positive sputum for AFB, while 61(22.3%) had positive sputum for fungal isolates. The most common fungal isolates were Aspergillus spp (42.9%), Scopulariopsis (14.3%), Chrysosporium (8.9%), Penicillium (7.1%), Fusarium (7.1%) and Acremonium (5.4%). No patient with mold isolate had cavitary lung disease, while 62.5% of TB patients had cavitary disease. Extensive disease (54.2%) and abnormal chest x-ray (91.7 %) were characteristic of patients with TB but very rare in patients with fungal infection. CONCLUSION: We therefore conclude that serious lower respiratory tract fungal infection was rare and that extensive or cavitary disease was usually due to pulmonary TB. The clinical diagnosis of TB under defined conditions, as in our setting, still has great utility.
BACKGROUND: In Maiduguri, Nigeria in the 1990's, we had available to us only the direct Acid Fast Bacilli (AFB) smear method to diagnose tuberculosis (TB), and no facility for TB culture. Because the clinical and radiologic manifestations of lower respiratory tract (LRT) fungal infections are difficult to differentiate from those of LRT TB, it was not clear how many of the direct AFB smear negative patients had fungal infections, or were true negatives for TB. OBJECTIVE: To assess sputum samples from patients with suspected lower respiratory tract infection for non-candidal fungal isolates as well as Mycobacterium tuberculosis. METHODS: Smears of sputum samples were examined microscopically for fungal hyphae and AFB. Sputum samples were also plated onto different fungal culture media. Isolation data were correlated with clinical and radiological data, to determine their clinical significance. RESULTS: Of the 274 patients seen, 41(15%) had positive sputum for AFB, while 61(22.3%) had positive sputum for fungal isolates. The most common fungal isolates were Aspergillus spp (42.9%), Scopulariopsis (14.3%), Chrysosporium (8.9%), Penicillium (7.1%), Fusarium (7.1%) and Acremonium (5.4%). No patient with mold isolate had cavitary lung disease, while 62.5% of TB patients had cavitary disease. Extensive disease (54.2%) and abnormal chest x-ray (91.7 %) were characteristic of patients with TB but very rare in patients with fungal infection. CONCLUSION: We therefore conclude that serious lower respiratory tract fungal infection was rare and that extensive or cavitary disease was usually due to pulmonary TB. The clinical diagnosis of TB under defined conditions, as in our setting, still has great utility.
Authors: Israel Kiiza Njovu; Benson Musinguzi; James Mwesigye; Kennedy Kassaza; Joseph Turigurwa; Edwin Nuwagira; Joel Bazira; Taseera Kabanda; Moses Mpeirwe; Lucas Ampaire; Andrew Mutekanga; James Kiguli; Beatrice Achan; Herbert Itabangi Journal: Ther Adv Infect Dis Date: 2021-08-31