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Clinical isolates of Sporothrix schenckii were investigated for mitochondrial DNA (mtDNA) types using restriction fragment length polymorphism patterns with HaeIII. The 62 isolates in South Africa comprised Types 3 (9· 7%), 4 (1· 6%), 11 (9· 7%), 17 (77· 4%) and 23 (1· 6%) while the 23 Australian isolates comprised Types 3 (26· 0%), 4 (56· 5%), 7 (8· 6%) and 21 (8· 6%). In a phylogenetic tree based on the sequence divergence of mtDNA, the mtDNA types were clustered into two groups, A and B. The results suggested that isolates in South Africa mainly belong to Group A and isolates in Australia mainly belong to Group B.

The first reported human case of possible disseminated infection with the insect pathogen Metarrhizium anisopliae var. anisopliae , a fungus which has been used commercially for biocontrol of insects, is described. The patient, a 9-year-old boy, had a 5-year history of pre-B-cell acute lymphoblastic leukemia and had been on chemotherapy throughout this period. After 10 days of profound neutropenia, lesions consistent with ecthyma gangrenosum appeared on his arms and legs. M. anisopliae was grown from specimens from three separate sites, collected at different times over a period of 1 month: a skin biopsy, a swab from the base of a lesion, and the core of another skin lesion which spontaneously discharged. The initial skin biopsy also showed histological evidence of epidermal necrosis and dermal invasion with fungal hyphae. A computed-tomography (CT) scan of the chest demonstrated a lesion in the superior segment of the lower lobe of the left lung. A CT scan of the brain revealed a lesion in the left temporoparietal region of the brain, consistent with an abscess. Despite antifungal treatment including liposomal amphotericin and 5-flucytosine, the patient eventually died. The initial portal of entry is unknown, but hematogenous dissemination to the skin appears likely because of the multiple ecthymic lesions, and the appearances of the brain lesion on the CT scan are consistent with a hematogenous fungal abscess.

Invasive mycotic rhinitis was diagnosed in a cat with a 4-month history of stertor, nasaldischarge and subcutaneous swelling of the nasal bridge. Histology demonstrated fungal hyphae in representative biopsies of the nasal cavity and subcutaneous mass.Mycological culture demonstrated a pure growth of Metarhizium anisopliae var. anisopliae. The infection was treated with orally administered itraconazole. This is the firstwell documented case of infection by M. anisopliae in a mammalian host.

The BioMerieux ID 32C Yeast Identification System was examined to determine its usefulness as a rapid method for the identification of medically important aerobic actinomycetes. More than 290 strains were tested by this method and the results were compared to those obtained by conventional methods. It was found that aerobic actinomycetes could be differentiated to species level in 7 days by the ID 32C system.

Nasal washings, obtained from a random source of dogs and cats, were concentrated by centrifugation and plated onto bird seed agar containing antibiotics. Cryptococcus neoformans var. neoformans was isolated from eight of 56 dogs (14%) and three of 45 cats (7%). More than 100 colonies of C. neoformans were present on the plates from seven of the 11 positive animals. Absence of cryptococcal antigen in the serum of these animals, and failure to demonstrate yeast-like organisms or significant pathology in nasal biopsies, suggests that the nasal cavity of these animals was not infected by C. neoformans but rather that blastoconidia and/or basidiospores were carried asymptomatically. These findings are discussed in relation to the likelihood of the upper respiratory tract being the primary site for cryptococcal infection in dogs and cats.

Five cases of human infection with Scedosporium prolificans are described. There were two groups of patients. In group one, two were immunocompetent males with localized bone and joint infections, a man with post-traumatic septic arthritis, responded to surgical treatment alone and a boy with post-traumatic septic arthritis, appeared to respond to treatment with oral fluconazole, without surgery. The second group consisted of three immunocompromised patients. S. prolificans was isolated at autopsy from the lungs of one patient with acute leukaemia, and from the lungs, liver, and kidneys of another. Nosocomial S. prolificans infection of a synthetic vascular graft occurred in the third patient with end-stage renal failure on corticosteroid therapy for idiopathic hypereosinophilia. His infection faied to respond to combinations of surgery, fluconazole and itraconazole. All isolates of S. prolificans were resistant in vitro to antifungal drugs, including the first case, which responded clinically to fluconazole.

Summary A retrospective study was undertaken of 192 cases of culture proven tinea capitis occurring between 1979 and 1988 in a predominantly white population of children in New South Wales (NSW). The aim of the study was to identify whether Trichophyton tonsurans was increasing in importance in the causation of this condition in Australia as it was in many other parts of the world. The results of our study were compared with those of earlier Australian studies. Our study demonstrated that Trichophyton tonsurans is now equal in importance to Microsporum canis which was previously the strongly predominant organism.

Over a 22-month period, sequential nasal and skin swabs were obtained from 52 healthy captive koalas (Phascolarctos cinereus) from the Sydney region. Cryptococcus neoformans was isolated in 17 koalas from 64 of 262 (24%) nasal swabs and from nine of 262 (3%) skin swabs. Prevalence of nasal colonization varied seasonally from 12% (3/25) to 38% (10/26). Cryptococcus neoformans var. gattii alone was cultured from 37, var. neoformans alone from 22 and both varieties from five nasal swabs. Of 33 koalas sampled on three or more occasions, organisms were isolated persistently from six, occasionally from eight and never from 19. Two koalas were persistently and heavily (>/=100 colonies/plate) colonized by C. neoformans var. gattii and two with var. neoformans. Isolation of C. neoformans var. gattii from the skin was low grade and sporadic. No koalas from which C. neoformans was persistently isolated showed clinical signs of cryptococcosis and all except one had a negative latex cryptococcal antigen test, therefore the nasal cavity was presumed to be colonized by, rather than infected with, C. neoformans. Preliminary observations of koalas from Coffs Harbour indicated a much higher prevalence of colonization by C. neoformans, suggesting that environmental factors influenced the extent of carriage by C. neoformans.

The clinical and mycological findings in 20 consecutive cases of cryptococcosis evaluated between 1981 and 1995 were analysed retrospectively. Typically, young adult dogs (median age 2 years) of either sex were affected. Dobermann Pinschers and Great Danes were significantly over-represented in relation to other breeds and crossbred dogs, and there was no trend for cryptococcosis to be acquired at a particular time of year. Cryptococcus neoformans was cultured from 18 dogs, with 16 isolates further characterized. Of these, C. neoformans var. neoformans was isolated from 12 cases, while the remaining four strains were C. neoformans var. gattii. Dogs with C. neoformans var. gattii infections resided in rural (two cases) or suburban (two cases) environments. Ten dogs were presented as a result of infection of structures inside, adjacent to, or contiguous with the nasal cavity. Seven dogs were presented primarily for signs of central nervous system disease, of which at least three also had cryptococcal rhinosinusitis. One dog had cryptococcal pneumonia and also possible mycotic rhinitis, another had disseminated disease with lymph node and skin involvement, while the last dog was presented for vomiting referable to cryptococcal mesenteric lymphadenitis. Treatment consisting of surgery and/or antifungal drug therapy was successful in the majority of animals in which it was attempted, including two of three cases with meningo-encephalitis.

We report on 17 Australian cases of human infection or colonization with Scedosporium inflatum. The spectrum of clinical manifestations was similar to that in infection caused by Scedosporium apiospermum. The patients were classified into three groups. Four immunocompetent patients who presented with localized infections of a joint, nail bed, eye, or sphenoidal sinus made up the first group. Our first case, in a boy with posttraumatic septic arthritis, responded to surgical drainage with amphotericin B followed by treatment with itraconazole. The other three cases were cured by surgery alone. The second group consisted of five immunocompromised patients who presented with disseminated infections in a variety of sites. Four of these patients did not respond to antifungal therapy and died. The fifth apparently responded to antifungal drugs after correction of his neutropenia. The third group included eight patients with asymptomatic colonization in the external ear (five cases) or respiratory secretions (three cases). The nine isolates of S. inflatum tested by both disk and agar dilution methods were resistant to antifungal drugs. In our first case, which responded clinically to itraconazole, the MIC of this drug for the fungal isolate was 25 micrograms/mL. Thus S. inflatum can cause a broad spectrum of human infections whose severity and prognosis depend largely on the host's immune status.

Twenty-nine cats with naturally occurring cryptococcosis were evaluated prior to commencing oral fluconazole therapy (25-100 mg every 12 h). Affected cats ranged from 2 to 15 years-of-age. Male cats (19; 66%) and Siamese cats (5; 21%) appeared to be over-represented in comparison to the hospital's cat population. Mycotic rhinitis was observed in 24 (83%) of the cases, although nasal cavity involvement was subtle in four animals. Disease of the skin and subcutaneous tissues was present in 15 cases (52%) and amongst these the nasal plane (seven cats) and bridge of the nose (seven cats) were most commonly involved. Primary infection of the central nervous system was not encountered, although one cat developed meningoencephalitis and optic neuritis as a sequel to longstanding nasal cavity disease. Antibodies against the feline immunodeficiency virus (FIV) were detected in eight cats (28%), and these cats tended to have advanced and/or disseminated disease. There was a tendency for cats to develop cryptococcosis during the Australian summer. Organisms were cultured from 27 cases. Cryptococcus neoformans var. neoformans was isolated from 21 cats, while C. neoformans var. gattii was identified in the remaining six. The response to oral fluconazole was excellent in this series, which included many cats with advanced, longstanding or disseminated disease. The fungal infection resolved in all but one advanced case which died after only 4 days of therapy. A dose of 50 mg per cat, given every 12 h, produced a consistently good response without side effects. Lower doses were effective in some cases, while 100 mg every 12 h was required to control the infection in one cat. Serum fluconazole levels obtained during chronic dosing (50 +/- 18 mg l-1, mean +/- SD; 50 mg per cat every 12 h) were highly variable (range 15-80 mg l-1). Concurrent FIV infection did not impart an unfavourable prognosis, although affected cats often required prolonged courses of therapy.

Over a twelve month period, 25 platypuses (Ornithorhynchus anatinus) were presented for necropsy. The most common causes of mortality were dog predation (40%), road trauma (28%), starvation and/or exposure (16%) and Mucor-mycosis (8%). Mucor amphibiorum is the only disease agent known to cause significant morbidity and mortality in free-living O. anatinus in Tasmania. This fungus causes a severe, granulomatous, commonly ulcerative, skin condition in this species. A study was conducted to define the nature and extent of the granulomatous dermatitis caused by M. amphibiorum. The mycotic granulomatous dermatitis of O. anatinus appears to be confined to streams in the north and midlands. The prevalence of the disease at two infected sites was 36% (n=36) and 66% (n=3). Lesions included abscesses, ulcers, granulation tissue and nodules. Of the 17 diseased animals captured, II were adult male, 5 were adult female and 1 was a juvenile female. Thirteen isolates of M. amphibiorum were cultured from skin lesions, all were of the positive mating type. Mucor amphibiorum was not isolated from 40 faecal or 8 skin samples from O. anatinus. No M. amphibiorum was isolated from 14 environmental samples. Mucor circinelloides and M. saturninus were isolated from soil, and M. circinelloides and M. hiemalis were isolated from faecal samples from O. anatinus.

Two hundred and eight isolates of Trichosporon beigelii were identified over the period January 1973 to July 1983. 45.7% of these were from skin, 25.0% from nail, 22.6% from tissues and fluids, 3.4% from hair and 3.4% from sputum. Tr. beigelii was isolated in association with a recognized pathogen in 23 cases, 9 with a yeast, 14 with a dermatophyte. In 38 cases, Tr. beigelii was the only organism isolated when direct microscopic examination of clinical material showed the presence of hyphae and/or yeast cells. Although Tr. beigelii could only be assigned a definite pathogenic role in 6 cases of genital white piedra, and in one case of peritonitis associated with chronic ambulatory peritoneal dialysis, we believe that this organism was pathogenic in many cases of skin infection. In most of the cases where it was isolated from tissue or fluids at Royal North Shore Hospital, Tr. beigelii was not considered to be significantly contributing to the disease process.

Over a 17 yr period from 1966 to 1982, 4354 dermatophytes were identified at the Australian National Reference Laboratory in Medical Mycology. The most frequently identified species was Trichophyton rubrum, accounting for 35.3% of identifications, followed by Trichophyton mentagrophytes (26.5%), Trichophyton tonsurans (12.8%), Epidermophyton floccosum (10.7%) and Microsporum canis (8.4%). Specimens taken from the feet were the most common source of the Trichophyton rubrum isolates, followed by specimens from the groin. The highest incidence of T. rubrum and other Trichophyton infections was found in males in the age group 21-30 yr. Microsporum species were most commonly isolated from children aged 10 yr or less. In 1.5% of specimens, more than one fungal species was isolated. In most of these instances a yeast (predominantly Candida species) was found in addition to a Trichophyton species.

Five hundred and fifty six dematiaceous hyphomycetes, the great majority referred from other laboratories, were identified by us over a five year period. Of these, thirty five were regarded as being of probable pathogenetic significance. These included seven isolates associated with chromoblastomycosis, and seven isolates thought to be causing phaeohyphomycosis. There were six strains of Phaeoannellomyces werneckii and five strains of Sporothrix schenckii. Seven isolates, all strains of Aureobasidium pullulans, were associated with fungal peritonitis in patients on chronic ambulatory peritoneal dialysis. Two Bipolaris isolates were associated with paranasal sinus fungus ball, a condition in which no evidence of tissue invasion by fungi could be found, even though pressure necrosis of bone could lead to very serious consequences. A further seven dematiaceous hyphomycetes, isolated from cases of paranasal fungus ball, keratitis and otitis externa, were thought to be of possible pathogenetic significance. Of the remaining 514 isolates thought to be of no pathogenetic significance, two thirds were made up of strains of Aureobasidium pullulans, Alternaria alternata, Cladosporium cladosporioides, Epicoccum purpurascens and Phoma species. In many cases it was thought that the referring laboratories had allowed insufficient time for development of conidiogenesis in these strains, before sending them to our laboratory for identification.

A case of localized, subcutaneous infection in the cheek of a three-month-old girl that was caused by the zygomycete Saksenaea vasiformis is reported. This is the fourth report of infection in Australia that was due to this fungus and, in contrast to all but one of the few previous reports in the literature, a cure was effected by surgical debridement alone.