Trichosporon asahii as an emerging etiologic agent of disseminated trichosporonosis: a case report and an update

Abstract

Purpose: To report a fatal case of disseminated trichosporonosis caused by Trichosporon asahii in a patient with acute myeloblastic leukemia (AML) and to present an update on systemic trichosporonosis with special reference to India.

Methods: The diagnosis was based on repeated demonstration of budding yeast cells and arthroconidia by direct microscopic examination of sputum and by isolation of T. asahii in culture of sputum and blood. The update is largely based upon literature search in Medline and Review of Medical and Veterinary Mycology.

Results: A 41-year-old male presented with acute myeloblastic leukemia, cough and fever. He had received cytotoxic drug therapy, broad spectrum antibiotics and was neutropenic. Trichosporon asahii was repeatedly demonstrated in his sputum by direct microscopy and culture, and also isolated from blood. It was identified by appropriate morphological and physiological characteristics viz., arthroconidium formation, diazonium blue B reaction, urease activity and assimilation of carbon and nitrogen compounds. The identification was confirmed by PCR amplification and direct DNA sequencing of internally transcribed spacer (ITS) 1 and ITS2 of rDNA.

Conclusion: With greater awareness of etiologic significance of T. asahii, trichosporonosis is likely to be recognised more frequently than apparent from the available published reports.