Human pathogenic fungi in China--emerging trends from ongoing national survey for 1986, 1996, and 2006.

This epidemiological survey was a retrospective study on three nodes during the past three decades on fungal infections representing the China, including Taiwan. Owing to rare publications reporting on dynamic epidemiological trends in the pathogen epidemiology in China, we surveyed the isolation rates and pathogenic fungi from 8 representative districts in China using uniform identification with uniform methodology. The pathogenic fungi isolation rates and species obtained from 1986 (n=9,096), 1996 (n=19,009), and 2006 (n=33,022) suggested that Trichophyton rubrum was the commonest organism cultured in 1980s (45.4%) and 1990s (34.5%), but Candida albicans increased significantly and reaching to its peak (26.9%) in 2006s' survey, and has become the most common isolate of fungal infections in China currently. In addition, Candida glabrata became the most common non-albicans species of Candida in 2006s' survey. At the same time, the incidence of molds also gradually increased. According to comparative analysis of the results of these three surveys, we found apparent differences in the isolation rates of different pathogenic fungi and the forefront 10 species in China varied significantly, and the dermatophytes decreased markedly, while yeasts, especially the Candida species and the molds, increased gradually during the past three decades. Less dermatophytic infections may suggest better access to healthcare or increase in Candida species indicated higher incidence of hospital acquired infections.

Pyoderma gangraenosum caused by Rhizopus arrhizus.

A rare case of pyoderma gangraenosum caused by Rhizopus arrhizus is reported. The patient, a 50-year-old male farmer, was admitted to hospital complaining of gangrening and festering of the right upper arm with severe pain for nearly 2 months. A lesion was found on the inside of right upper arm. The central skin part of the lesion became black dry gangrenous, the periphery was deeply ulcerated with yellow-green pus. The necrotic crust, biceps, triceps and vessels inherited a histopathologically proven fungal infection. The fungus isolated was identified as Rhizopus arrhizus. The infection was successfully treated with itraconazole.

Candida zeylanoides causing candidiasis as tinea cruris.

Candida zeylanoides caused candidiasis as tinea cruris in 4 cases. Candida zeylanoides were characterized by good growth of the strain in malt medium, potato dextrose agar and Sabourard's agar. Their colony was milky white and greasy with smooth surface. The diameter of the colony reaches 12 mm within a week. As candida type pseudohyphae but not hyphae, they do not produce ascospore and bolospore. Carbon sources fermentation showed positive results. Nitrogen sources assimilation agar (KNO3) negative, arbutin agar negative, nonvitamin medium positive. G+C mol% value of their DNA was 51.24. Animal experiment showed that guinea pigs were infected by Candida zeylanoides. The main feature of candidiasis as tinea cruris caused by the strain was pink infiltrative erythema with clear margin, a lot of grain-sized papules, a few vesicles, and thin scales. The disease can be cured by preparation of ketoconazole.

Research on rapid identification of auto-microbiology system for pathogenic yeast.

The auto-microbiology system yeast biochemical card (AMS-YBC; Vitek System, Inc.) was studied in 77 clinical isolates and 50 laboratory kept isolates on the basis of routine identification. Results of 123 isolates were obtained in 24 hours, while that of the other 4 in 48 hours. 122 (96.1%) were coincidently identified with AMS and routine method. The results suggest that AMS is a rapid, accurate and simple identification method for common pathogenic yeast.

Sporotrichosis presenting as pyoderma gangrenosum.

A 56-year-old female with an eight-year history of corticosteroid therapy for rheumatoid arthritis presented with large, deep, painful ulcers on the left buttock and thigh. The lesions appeared typical of pyoderma gangrenosum. Nine separate cultures of the exudate grew Sporothrix schenckii. During the course of iodide therapy, the patient expired due to Escherichia coli pneumonia. This is the third case report of sporotrichosis presenting as pyoderma gangrenosum and the first report from China. Sporotrichosis presenting as pyoderma gangrenosum is a special form of this disease. It develops quickly and must be treated promptly. Only two cases have been reported in the world literature. This is the first case reported from China.

Cepholosporium acremonium. A new strain of fungus causing white piedra.

A strain of fungus (CZ408) was isolated from white piedra of a female child. Mycological identification showed that it is the first case in the world. Asymptomatic white nodules were noted on the hair of the scalp, and they were distributed irregularly along the shaft 4-10 cm from the scalp. The nodules, hard, not easily broken or removed, consist of hyphae, spores and metabolic materials around the hair. Oral antimycotic drugs are effective in treating this disease.