Misdiagnosis: TB vs Aspergillosis

Pulmonary aspergillosis
Source: Radiopaedia.org

Pulmonary tuberculosis continues to be the scourge of humanity. After treatment, recurrent disease can be vexing to diagnose and in a not insignificant number of cases, per a WHO report, 22% of TB recurrences were actually a fungal disease (chronic pulmonary aspergillosis). This report is summarized in Infection Control Today. For the original paper, I refer you to the Bulletin of the World Health Organization.

Both TB and aspergillosis can be difficult to confirm. The radiographic (x-ray) changes are similar, cultures are frequently difficult to obtain, and the pathogens are not rapidly identified in the laboratory. Additionally, couple these challenges with resource poor settings where diagnostic testing is frequently not feasible, and confirmation of either pathogen proves even less realistic.

The treatments for these diseases are very different and misdiagnosis can result in a catastrophic outcome. Better mechanisms for differentiating TB from pulmonary aspergillosis, especially in resource poor settings, are needed.