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Deep-seated trichosporonosis is a lethal opportunistic infection occasionally found in immunocompromised patients, particularly those who are neutropenic due to cytotoxic therapy for hematological malignancies. Trichosporon asahii is considered the principal etiologic agent of non-Candida fungemia and disseminated trichosporonosis in Japan. This infection may disseminate to multiple organs and difficult to diagnosis and treat. Because clinical findings and courses of trichosporonosis are similar to disseminated candidasis, it is impossible to distinguish these infections without fungal isolation. Monotherapy of amphotericin B is thought to be unsuccessful for this infection, and new antifungal agents echinocandins are also not active against Trichosporon species. Some clinical reports and animal models suggest that triazoles and combination therapies are most effective drugs against trichosporonosis. Recently, T. asahii isolates with reduced susceptibility in vitro to multi-antifungal agents are reported. T. asahii is the allergen of summer-type hypersensitivity pneumonitis and sometimes isolated from the houses environments, but it is not clear that the environmental strains directly infect to human. There is no clinical evidence that Trichosporon is the common outbreak pathogen in the hospital. However, it is necessary for a clinician to pay enough care as the lethal infections in immunocompromised patients.

We detected the metallo-beta-lactamase gene blaIMP positive strains of the gram-negative rods (GNR) isolated in Oita Medical University Hospital between 1993 and 1999 and studied the clinical characteristics of patients infected or colonized with blaIMP positive GNR. 25 strains (20 Pseudomonas aeruginosa and 5 Serratia marcescens) were detected and most of them were isolated from urinary samples after 1997. In the studies of antimicrobial susceptibility, some strains had sensitivity to aztreonum or imipenem although most of the strains showed multidrug resistance. When blaIMP positive GNR were isolated from patients, these strains were thought to have caused infection in 88% of the patients. About half of the patients were over 65 years old and had malignant diseases. Most of the patients had inserted urinary tract catheters, intratracheal tube or intravernous catheters. It was suggested that the insertion of the catheters were related to infection of blaIMP positive GNRs. Two patients were not treated with any antibiotics before the isolation of blaIMP positive GNRs although more than half of the patients were administered carbapenems and cephems. Most of strains were isolated in the same department and showed the same genotype by pulsed field gel electrophoresis.

In this study, cytomegalovirus (CMV) infection was found in eleven of 21 autopsied cases (52.4%) with adult T-cell leukemia (ATL). Seven cases (63.6%) revealed disseminated infection in more than three organs. The lungs were involved in all eleven cases (100%), adrenal glands in eight cases (72.7%), esophagus in four cases (36.4%), and stomach, small intestine and urinary bladder in three cases (27.3%). Histopathological findings suggested that lung involvement was the cause of death in five of the 11 cases, the small intestine were involved in two of the 3 cases, and the adrenal glands were involved in one of the 8 cases. In summary, CMV infection was found to be the main cause of death in five (45.5%) of the 11 ATL patients.

A 64-year-old male was admitted to Oita Medical University Hospital because of primary lung cancer. After the anticancer chemotherapy, the patient developed a high fever. His chest X-ray showed diffuse reticular shadows bilaterally, which were considered to be a drug induced pneumonia, then pulse therapy with corticosteroid was performed. With this treatment, the diffuse reticular shadows disappeared. One month later, however, a severe interstitial pneumonia developed, and the patient died of respiratory failure. Autopsy findings demonstrated cytomegalovirus (CMV) and Pneumocystis carinni pneumonia. The polymerase chain reaction (PCR) for CMV in mononuclear cells in the blood was positive through out his hospitalization. In the sera, however, it was negative at the time of admission, then became positive 10 days before the onset of pneumonia. In addition, the PCR for P. carinni on the swab became positive as well. These results imply that PCR can be used for diagnosis of CMV and P. carinii infections from sera or swabs.