Several lung fungal infections can be mistaken for TB – histoplasmosis, aspergillosis, coccidioidomycosis and paracoccidioidomycosis. Antibody testing and fungal culture of sputum are the means of establishing the diagnosis. The number of incident cases of these fungal infections varies substantially by region and country and the rate of misdiagnosis of TB-like fungal infections is not known. But examples include
- In the 1950s 7.2% of patients in a Missouri TB sanatorium had chronic pulmonary histoplasmosis (Furcolow, 1956).
- In Iran, Aspergillus antibody was detected in 29% of 94 patients finishing TB therapy (93.7% smear positive) and 93% of those with recurrent or persistent ‘TB’ after finishing treatment (Hedayati, 2015).
- 19% of smear and GeneXpert negative, HIV negative Nigerians had chronic pulmonary aspergillosis, and not TB (Oladele, 2017).
- Among 48 MDR-TB cases in Sao Paulo, Brazil, fungal co-infection was diagnosed in 15% 3 with chronic pulmonary aspergillosis and 4 with paracoccidioidomycosis (Bollela, 2016)
- In California, 70% of patients received antibiotics before and 36% after they had a positive serological test for coccidioidomycosis (Chi et. al., 2020).
- A meta-analysis of 17 studies from India, Cameroon, Egypt, Kenya, Iran and Iraq of Aspergillus infection by respiratory culture and concurrent TB in 15.4% (Hosseini, 2020).
GAFFI urges governments to ensure fungal antibody testing, especially for aspergillosis, to be apart of all TB programs to reduce mis-diagnosis and diagnosis co-infection.