Is Bjerkandera adusta Important to fungus-associated chronic cough as an allergen? Eight cases' reports

Recently, we have reported a new clinical disease concept called fungus-associated chronic cough (FACC), which entailed the following manifestations: (1) chronic cough; (2) the presence of environmental fungi, particularly basidiomycetous (BM) fungi, in the sputum; and (3) good clinical response to antifungal drugs. To clarify the relationship between the exposure to environmental fungi and the development of cough attacks, we reviewed the clinical records of patients with FACC and performed a molecular biological analysis of the BM fungi.

We successfully selected 8 patients with chronic cough, wherein a sputum culture yielded B. adusta beforehand; moreover, we conducted allergological tests such as the immediate-type skin test, a serological test, bronchoprovocation test, and lymphocyte stimulation test (LST), using the antigenic solution of B. adusta. The efficacy of individualized therapy and the clinical manifestations in the eight patients were examined.

All the eight patients were diagnosed with FACC. Although three patients who did not show a positive reaction to the bronchoprovocation test or LST showed excellent clinical response to anti-fungal drugs; other 5 patients who showed a positive reaction to the bronchoprovocation test and/or LST seemed to be more intractable because of taking a longer time for complete remission and more frequent recurrence of cough.

It was suggested that so-called allergic fungal cough (AFC), which is characterized by sensitization to B. adusta, may be included in a part of chronic intractable cough.