Two Cases of Cryptococcuria Developed as Isolated Cryptococcuria and Disseminated Cryptococcosis / 대한임상미생물학회지

Cryptococcus is an opportunistic pathogen that mainly affects immunocompromised hosts and, less frequently, immunocompetent hosts. It causes serious morbidity and mortality due to systemic infections such as meningoencephalitis and pulmonary infection. Urinary involvement of Cryptococcus is sometimes reported among cases of disseminated cryptococcosis in AIDS patients, but no such reports have been published in Korea. We report two cases of cryptococcuria that developed in a 71-year old female with diabetes and liver cirrhosis and in a 50-year old male who received a liver transplant due to HBV-associated hepatic failure. The female patient had received prednisolone for 12 days before we detected C. neoformans in urine culture. Even though no antifungal therapy was indicated for cryptococcuria, following urine culture became negative, but still positive for cryptococcal antigen on hospital day 25. Her blood, CSF culture, and antigen tests were negative, and therefore she was diagnosed with isolated cryptococcuria. The male patient had received prednisolone and tacrolimus for 10 days before sputum and urine cultures became positive for C. neoformans. He had ill defined nodules and pleural effusion in both lungs on chest CT. His cryptococcuria was sustained for over 2 months, despite receiving amphotericin B treatment. His cryptococcuria seemed to be a symptom of disseminated cryptococcosis.

Microbiological and Epidemiological Characteristics of Vancomycin-dependent Enterococci / 대한진단검사의학회지

BACKGROUND: Vancomycin-dependent enterococci (VDE) are clinically equivalent to vancomycin-resistant enterococci (VRE), but more difficult to detect. This study was purposed to characterize VDE microbiologically and epidemiologically. METHODS: The patients from whom VDE were detected from April 2007 to March 2008 were investigated. For available isolates, minimal inhibitory concentrations (MICs) of and the levels of dependence on vancomycin and teicoplanin were measured by E test (AB Biodisk, Sweden), and a test for reversion of VDE to non-dependent VRE (NDVRE) and pulsed field gel electrophoresis (PFGE) were performed. Patients' demographic and clinical findings were reviewed via electronic medical records. RESULTS: VDE were recovered from 6 (2.2%) of 272 patients carrying VRE during this study period. All patients were already colonized or infected by VRE and treated with vancomycin for 13 to 107 days. VDE were isolated from pleural fluid (one), urine (four), and stool (one). All isolates carried vanA with vancomycin MICs of >256 microgram/mL, but two of them had intermediate susceptibilities to teicoplanin. Because 4 VDE isolates were reverted to NDVRE with single passage, vancomycin dependence was measurable for only two isolates as equal and above 0.064 and 0.5 microgram/mL respectively, and was reverted after 5 and 7 passages, respectively. Six VDE isolates showed no related clones in PFGE analysis, and 3 of 4 available pairs of initial VRE isolates and subsequent VDE isolates were identical clones. CONCLUSIONS: VDE were not rare and seemed to emerge independently from VRE with a prolonged use of vancomycin. Vancomycin-dependence was reverted within several passages.

The Evaluation of Clinical Utility of Platelia Aspergillus Antigen Immunoassay for Diagnosis of Invasive Aspergillosis / 대한임상미생물학회지

BACKGROUND: Because the mortality rate of invasive aspergillosis (IA) is more than 50%, an early diagnosis and appropriate management are important to achieve a favorable outcome. Aspergillus galactomannan(AG)antigen test has recently been introduced for diagnosis and monitoring of IA. This study was to evaluate the clinical utility of AG detection in diagnosis of IA. METHODS: One hundred and seventy-five samples from 149 patients were tested for AG during the period from September 2004 to May 2005 and the results were evaluated retrospectively. IA was diagnosed into 'proven','probable'and 'possible', groups based on patients' clinical laboratory findings as per European Organization for Research and Treatment of Cancer/Mycoses Study Group. AG was tested using a Platelia Aspergillus antigen ELISA (Bio-Rad, Hercules, CA, USA); the optical density (OD) of the test specimen was divided by the mean OD of two cut-off controls. The test was classified as positive when the OD ratio was > or =1.5; ratios 1-1.5 were classified as equivocal. Clinical Information was obtained from the electronic medical records of the patients. RESULTS: Of the 175 samples tested, 19 were positive, 14 equivocal, and 142 negative for AG. A number of the 'proven', 'probable', and 'possible'IA patients were 2, 15, and 28, respectively. At the OD ratio of 1.5, sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) were 76.9%, 94.7%, 58.8%, and 97.7%, respectively, when 4 false-negative patients treated with amphotericin B before Aspergillus antigen test were excluded. CONCLUSION: The Platelia Aspergillus ELISA demonstrated an excellent sensitivity, specificity and NPV for the diagnosis of IA. A combined use of the antigen test with microbiological and clinical evaluation might facilitate the early diagnosis of IA and, consequently, improve its clinical outcome.