A 50 year old female presented to our institution with worsening productive cough. The onset of her symptoms had coincided with exposure to a damp, poorly ventilated environment for several weeks prior to the onset of cough. Computed tomography (CT) of the chest demonstrated tree-in-bud changes most prominent in the right lower lobe with bronchiectasis. Symptoms and radiological changes progressed over 3 months. In three sputum samples the direct sample microscopy, using calcofluor’s fluorescent stain revealed numerous septate hyphae. Cultures after incubation for 34 days at 28 C and 37 C on sabouraud’s agar grew a white fluffy, spreading fungus. Initial microscopy of the fungal isolate showed a septate, hyaline fungus with hyphae of varying widths and also with some bizarre shapes. After further incubation, the isolate developed spicules along the hyphae and some crystals were also seen. No clamp connections were detected. The initial identification was a ’’basidiomycete’’ fungus. This fungus was subsequently identified as Schizophyllum commune, using fungal Internal Transcribed Spacer (ITS) region polymerase chain reaction (PCR). The patient underwent bronchoscopy to confirm the isolate and rule out other pathogens. The same organism was identified on the bronchial lavage. No other typical or atypical pathogens were identified on standard bacterial and mycobacterial culture. The patients’ serum IgE level was normal and pulmonary function testing and bronchial provocation testing showed no evidence of reversible airways disease. Susceptibility testing using SENSITITRE YeastOne resulted in M.I.C levels (mg l)1) of; amphotericin B 0.25, 5- fluorocytosine 0.5, posaconazole 0.5, voriconazole 0.06, itraconazole 0.25 and fluconazole 8. The patient was commenced on voriconazole for a period of 6 months. Her cough resolved, and follow-up CT showed mild bronchiectasis and no features of active inflammation. Schizophyllum commune is a cosmopolitan basidiomycete (mushroom) fungus commonly found on rotting wood. A review of reported cases suggests a spectrum of disease similar to aspergillus, from allergic bronchopulmonary mycosis and airway hyper-responsiveness to a more invasive type of infection. Although corticosteroids are typically used to treat ABPA/ABPM, the response to voriconazole along with absence of an IgE mediated immune response or bronchial asthma, and the extent of radiological change suggests a more invasive type of infection in this patient.
Full conference title:
18th International Society for Human and Animal Mycology
- ISHAM 18th (2012)