Cryptococcus neoformans and Cryptococcus gattii are closely related pathogenic fungi. Cryptococcus neoformans is ecologically widespread and affects primarily immunocompromised patients, while C. gattii is traditionally found in tropical climates and has been reported to cause disease in immunocompetent patients. L-Canavanine glycine bromothymol blue (CGB) agar can be used to differentiate C. neoformans and C. gattii, but there are few reports of its performance in routine clinical practice. Growth of C. gattii on CGB agar produces a blue color, indicating the assimilation of glycine, while C. neoformans fails to cause a color change. Using reference and clinical strains, we evaluated the ability of CGB agar and D2 large ribosomal subunit DNA sequencing (D2 LSU) to differentiate C. neoformans and C. gattii. One hundred two yeast isolates were screened for urease activity, melanin production, and glycine assimilation on CGB agar as well as by D2 sequencing. Seventeen of 17 (100%) C. gattii isolates were CGB positive, and 54 of 54 C. neoformans isolates were CGB negative. Several yeast isolates other than the C. gattii isolates were CGB agar positive, indicating that CGB agar cannot be used alone for identification of C. gattii. D2 correctly identified and differentiated all C. gattii and C. neoformans isolates. This study demonstrates that the use of CGB agar, in conjunction with urea hydrolysis and Niger seed agar, or D2 LSU sequencing can be reliably used in the clinical laboratory to distinguish C. gattii from C. neoformans. We describe how CGB agar and D2 sequencing have been incorporated into the yeast identification algorithm in our laboratory.Cryptococcus gattii (formerly Cryptococcus neoformans var. gattii) differs from the closely related C. neoformans in several ways, including a contrasting host profile and a reduced susceptibility to certain antifungal agents (19,20). Cryptococcus gattii has traditionally been thought to be geographically restricted to tropical and subtropical climates, although recent reports indicate that it can be found worldwide, including in regions with distinctly nontropical climates, like the Pacific Northwest (2,4,8,12,14,17,19). Clinically, the majority of cryptococcosis cases that occur in AIDS patients and other immunocompromised hosts are caused by C. neoformans var. neoformans or C. neoformans var. grubii. In contrast, C. gattii has been reported to cause meningoencephalitis and pulmonary infections in hosts who are generally immune competent (9,14,18).Since C. gattii is recognized as an emerging pathogen, it is important for the clinical microbiology laboratory to accurately differentiate it from C. neoformans. A recent proficiency testing survey administered by the New York State Department of Health indicated that only 7/140 (5%) clinical laboratories participating in the event were able to correctly identify C. gattii, while the remaining 95% of laboratories surveyed misidentified the isolate as C. neoformans (15). The critique that followed this proficiency event in...

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The genus Oscillibacter has been known since 2007, but no association to human infection has been reported. Here, we present four cases of Oscillibacter ruminantium bacteremia from hospitals across Denmark from 2001 to 2010. Correct identification is now possible, as the 16S rRNA gene sequence was recently made publicly available. CASE REPORTSC ase 1 (year 2001) is a 53-year-old man who was admitted to the medical department with nausea and diarrhea, with a previous medical history of insulin-dependent diabetes mellitus, alcohol dependency, and chronic pancreatitis. On admittance, his temperature was 35.6°C and his blood pressure was 70/50 mm Hg. The total leukocyte count was 32.3 ϫ 10 9 cells/liter (normal value range, 3.5 ϫ 10 9 to 8.8 ϫ 10 9 ), and the C-reactive protein level was 169 mg/liter (normal value, Ͻ10 mg/liter). Blood cultures were drawn and antibiotic treatment was initiated with intravenous benzylpenicillin, gentamicin, and metronidazole. After 1 day of incubation, blood cultures (Bactec Plus aerobic/F vial and Bactec 9240 automated instrument; Becton, Dickinson Diagnostic Instrument Systems, Franklin Lakes, NJ, USA) were positive with coagulase-negative staphylococci, and the following day, after 45 h of incubation, the anaerobic vial (Bactec Plus anaerobic/F) showed growth of anaerobic Gram-negative rods. Benzylpenicillin was discontinued in favor of intravenous cefuroxime.The patient became afebrile but developed diffuse abdominal pains. A computerized tomography scan of his abdomen showed pancreatic calcifications and small quantities of peritoneal ascites. New blood cultures drawn were negative, and antibiotics were discontinued after a total of 10 days of treatment. The patient subsequently developed a large pleural effusion, but successful pleuracentesis could not be performed and the patient succumbed.The Gram-negative rods isolated from the first set of blood cultures were sent to an anaerobe reference laboratory and identified using conventional anaerobic identification methods (1) as a possible Clostridium species.Case 2 (year 2002) is a 78-year-old man who was admitted to the department of medicine with fatigue and epistaxis and with a previous medical record of ulcerative colitis, a mechanical aortic valve due to severe aortic stenosis, and hemicolectomy, including sigmoidectomy due to colon adenocarcinoma. The C-reactive protein level was 121 mg/liter, and the erythrocyte sedimentation rate was elevated to 110 (normal value, 0). The total blood leukocyte count was not elevated, and he was afebrile. Blood cultures drawn on admittance were without growth. The patient was diagnosed with a relapse of the colonic adenocarcinoma with metastasis to the liver and discharged 20 days later. Blood cultures (Bactec Plus anaerobic/F vial) drawn 1 day prior to discharge showed growth of anaerobic Gram-negative rods. The isolate was sent to an anaerobe reference laboratory and identified as a possible Clostridium sp. by using conventional anaerobic identification methods (1). To our knowledge, the...

Staphylococcus aureus is a major human pathogen in catheter-related infections. Modifying catheter material with interpenetrating polymer networks is a novel material technology that allows for impregnation with drugs and subsequent controlled release. Here, we evaluated the potential for combining this system with plectasin derivate NZ2114 in an attempt to design an S. aureus biofilm-resistant catheter. The material demonstrated promising antibiofilm properties, including properties against methicillin-resistant S. aureus, thus suggesting a novel application of this antimicrobial peptide.