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Summary.A study of the morphotypes of 446 strains of Candida albicans, isolated from a variety of clinical specimens, is reported. The method was based on a morphotyping scheme that has recently been described, but not all of the potential characters were used in this analysis. By this limited code, 50 different morphotypes were distinguished, the largest group comprising 23% of the population. The simplicity and good discrimination of the method make it a useful typing scheme for C. albicans. Discontinuous colonial fringes were associated with strains from oral sites and deep infections. Significantly, 67% of strains from fatal infections were of the discontinuous fringe type, compared to only 11% of strains from other infections. Further associations between morphotype and anatomical source included narrow-coarse fringes in genitourinary isolates.

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Strains of Candida albicans can be differentiated by the morphological features of streak colonies developed on malt agar. A morphotyping system is proposed, where numerical codes are assigned primarily on the basis of the nature and extent of marginal fringing and the surface topography of the streak colony. The system allows ready differentiation to be made of morphotypes, requires no specialized equipment or expertise and provides a simple and reproducible means for epidemiological studies of candida and candidosis.

To establish a model to study the immunoreactivity of oligosaccharidic structures from the Candida albicans cell wall, we attempted to construct neoglycolipids with these residues by using oligomannosides released after mild acid hydrolysis of the phosphopeptidomannans isolated from yeast forms. From a mixture of manno-oligosaccharides ranging from mannobiose to mannononaose, the structure of a quantitatively major component (mannotriose) was determined to be Man (beta 1-2) Man (beta 1-2) Man alpha by 1H nuclear magnetic resonance analysis. After coupling of the pool of oligosaccharides to a lipid (4-hexadecylaniline), the synthesized molecules were injected into mice and rats. Antibody responses were detected on enzyme-linked immunosorbent assay plates coated with either phosphopeptidomannans or neoglycolipids. The hybrid molecules exhibited both immunogenicity and antigenicity. The kinetics of antibody responses as well as immunofluorescence patterns observed on whole C. albicans cells strongly mimicked results from the immunization of animals with natural antigens. Construction of neoglycolipids could therefore provide an interesting approach to the study of specific oligosaccharides of C. albicans and their recognition by the host immune system.

An ELISA for the detection and measurement ofAspergillus antigenaemia has been developed and evaluated by examining sera submitted over a 12-month period from immunocompromised patients with a likelihood of invasive aspergillosis. Results from proven cases ofinvasive aspergillosis confirmed at post-mortem and specimens from individuals with suspected disease showed that tests on single serum samples were often negative. Multiple specimens from the same patient greatly increased the frequency of deteclion. Repeated monitoring of sera from a single patient showed wide fluctuations in antigen level, which was considered to be due partly to the medical regimen to which the patient was subject. Control sera from healthy laboratory personnel were consistently negative, but a number of 'at-risk' patients without other evidence of invasive aspergillosis sometimes had low amounts of antigen.Concentrations of Aspergillus antigen of 100 ng ml-~ or higher were considered to be strongly suggestive of fungal invasion.Patients whose host defense mechanisms have been compromised by immunosuppressive drug therapy are particularly susceptible to invasive fungal infection. In such cases cultural methods of detection and serological tests for antibody are often unsatisfactory.Enzyme-linked immunosorbent assay (ELISA), radioimmunoassay (RIA) and agglutination procedures have been reported which detect antigenaemia in patients with candidosis [25,19,2,8] and coccidioidomycosis [22]. Detector antigens that have been used with success in inhibition systems include Candida cell wall mannan [25,19] and cytoplasmic antigen from Candida yeast phase cells. Similar tests have been evaluated as diagnostic aids for aspergillosis. The antigens used as sensitizing agents for detector plates in ELISA inhibition tests include predominantly carbohydrate entities [18], glycoprotein fractions [14] and purified galactomannan [7]. Some of these antigens have also been used in RIA procedures, namely purified galactomannan [7]

Summary Forty‐four cases of mycetoma (madura foot) presenting in the United Kingdom between 1963 and 1981 have been analysed. The majority of the patients originated from the tropics particularly the West Indies (41%). The commonest organisms isolated belonged to the pale grain eumycetoma (true fungal mycetoma) group, particularly Petriellidium boydii or Fusarium spp. However, in four instances the infecting organism was not identified because of a lack of distinguishing characteristics. All seven patients from the Middle East had actinomycetoma infections caused by Streptomyces somaliensis. The diagnosis and management of three patients are discussed in more detail.