Seishi Osabe

Autopsy case of disseminated Trichosporon inkin infection identified with molecular biological and biochemical methods

Trichosporon species are usually opportunistic pathogens. Disseminated trichosporonosis is uncommon but is increasingly reported with a high mortality rate, especially in immunocompromised patients. Although Trichosporon asahii and T. mucoides are known as the most common pathogens of disseminated trichosporonosis, cases of systemic infection due to T. inkin have been reported recently. However, no autopsy case of disseminated T. inkin infection has been reported. Herein is presented an autopsy case of disseminated trichosporonosis caused by T. inkin in a 30‐year‐old man with allogenic peripheral blood stem cell transplantation for acute myelocytic leukemia. In the present case, identification of T. inkin was performed with morphological, molecular biological and biochemical methods. It is difficult to make a diagnosis of Trichosporon infection on only histological examination; therefore, molecular biological and biochemical methods are needed in a diagnosis of disseminated trichosporonosis.

Rapid diagnosis of cryptococcal meningitis by microscopic examination of centrifuged cerebrospinal fluid sediment

The classic India ink test is positive in only half of cryptococcal meningitis cases, and reliable, rapid cryptococcal antigen (CRAG) testing requires technical expertise and facilities not always available. We therefore examined cerebrospinal fluid (CSF) sediment using May-Giemsa, periodic acid-Schiff, and Gram stains in 16 patients with cryptococcal meningitis. The India ink test was positive in seven patients (44%), while microscopic examination of sediment revealed cryptococci in 13 (81%); in six of these 13 the India ink test was negative. Both methods failed to detect the pathogen in the remaining three patients. CRAG testing in CSF was negative in two patients (one with acquired immunodeficiency syndrome, one with diabetes mellitus) whose India ink test also was negative while cryptococci were identified in their CSF sediment. No false positives occurred with CSF May-Giemsa staining in 27 cases of aseptic meningitis with negative cultures for Cryptococcus. In all, microscopic examination of centrifuged and stained CSF sediment proved more sensitive for rapid diagnosis of cryptococcal meningitis than the India ink method, and in two of our patients cryptococci were seen in centrifuged CSF sediment despite negative CRAG and India ink tests.