This communication describes the consensus multi-locus typing scheme established by the Cryptococcal Working Group I (Genotyping of Cryptococcus neoformans and C. gattii) of the International Society for Human and Animal Mycology (ISHAM) using seven unlinked genetic loci for global strain genotyping. These genetic loci include the housekeeping genes CAP59, GPD1, LAC1, PLB1, SOD1, URA5 and the IGS1 region. Allele and sequence type information are accessible at http://www.mlst.net/.

Invasive fungal diseases (IFDs) have become major causes of morbidity and mortality among highly immunocompromised patients. Authoritative consensus criteria to diagnose IFD have been useful in establishing eligibility criteria for antifungal trials. There is an important need for generation of consensus definitions of outcomes of IFD that will form a standard for evaluating treatment success and failure in clinical trials. Therefore, an expert international panel consisting of the Mycoses Study Group and the European Organization for Research and Treatment of Cancer was convened to propose guidelines for assessing treatment responses in clinical trials of IFDs and for defining study outcomes. Major fungal diseases that are discussed include invasive disease due to Candida species, Aspergillus species and other molds, Cryptococcus neoformans, Histoplasma capsulatum, and Coccidioides immitis. We also discuss potential pitfalls in assessing outcome, such as conflicting clinical, radiological, and/or mycological data and gaps in knowledge.

A total of 356 clinical isolates of the encapsulated basidiomycetous fungus Cryptococcus neoformans var. neoformans, obtained from Australia, Argentina, Brazil, India, Italy, New Zealand, Papua New Guinea, South Africa, Thailand and the USA, were analyzed to lay the basis for a comprehensive evaluation of the global genetic structure of C. neoformans. Two polymerase chain reaction (PCR)‐based typing techniques were standardized: PCR fingerprinting using a single primer specific to minisatellite or microsatellite DNA, and randomly amplified polymorphic DNA (RAPD) analysis using two combinations of three 20‐ to 22‐mer random primers. Previous studies showed that the resultant profiles are reproducible and stable over time. Identical results were obtained in two different laboratories and by different scientists in the same laboratory. Both typing techniques separated the isolates into four major groups (VNI and VNII, serotype A; VNIII, serotype A/D; and VNIV, serotype D). The majority (78%) of isolates belonged to VNI, compared with 18% VNII, 1% VNIII and 3% VNIV. All US isolates could be differentiated by a unique, strain‐specific PCR fingerprint or RAPD pattern in contrast to most of the non‐US isolates, which showed a substantially higher degree of genetic homogeneity, with some clonality, in different parts of the world. Isolates obtained from the same patient at different times and from different body sites, had identical banding patterns. Both typing techniques should provide powerful tools for epidemiological studies of medically important fungi.

During a European Confederation of Medical Mycology (ECMM) prospective survey of cryptococcosis in Europe (from July 1997 to December 1999) 655 cases were reported from 17 countries; 565 of the completed questionnaires were evaluable. Cryptococcosis was associated with HIV infection in 77% of cases (range 57.5-94%). Assessment of the laboratory data highlighted the lack of defined standard procedures for the diagnosis of cryptococcosis: the antigen test was not usually used for screening, the disease was mainly recognised when meningitis occurred (65% of patients) and, with the exception of a few cases, the extent of the infection was not investigated. Cryptococcus neoformans was the etiological agent in all of the cases except for six caused by C. gattii and four by other Cryptococcus species. A total of 311 C. neoformans strains were serotyped by Crypto Check latex agglutination, genotyped by PCR-fingerprinting using the (GACA)4 oligonucleotide as a single primer, and their mating type was determined by PCR of the STE20 alleles. Serotype A was the most represented (51% of the isolates), followed by serotype D (30%) and serotype AD (19%). PCR-fingerprinting analysis significantly increased the percentage of hybrid strains to 30%, as 6% of the serotype A and 28% of the serotype D isolates were of the VN3 or VN4 hybrid genotype. In addition, the mating type determinations revealed the MATa serotype A allele in one haploid strain and 28 hybrids, and hybrid isolates with a single mating type (four Aalpha and two Dalpha) were also identified. This is the first prospective survey to be carried out in Europe which has attempted to investigate the epidemiology of cryptococcosis and the population structure of C. neoformans, and the results obtained thus far show the widespread involvement of AD hybrid strains in C. neoformans infections.