Chrysosporium anamorph of Nannizziopsis vriesii associated with fatal cutaneous mycoses in the salt-water crocodile (Crocodylus porosus)

Major Emerging Fungal Diseases of Reptiles and Amphibians

Emerging infectious diseases (EIDs) are caused by pathogens that have undergone recent changes in terms of geographic spread, increasing incidence, or expanding host range. In this narrative review, we describe three important fungal EIDs with keratin trophism that are relevant to reptile and amphibian conservation and veterinary practice. Nannizziopsis spp. have been mainly described in saurians; infection results in thickened, discolored skin crusting, with eventual progression to deep tissues. Previously only reported in captive populations, it was first described in wild animals in Australia in 2020. Ophidiomyces ophidiicola (formely O. ophiodiicola) is only known to infect snakes; clinical signs include ulcerating lesions in the cranial, ventral, and pericloacal regions. It has been associated with mortality events in wild populations in North America. Batrachochytrium spp. cause ulceration, hyperkeratosis, and erythema in amphibians. They are a major cause of catastrophic amphibian declines worldwide. In general, infection and clinical course are determined by host-related characteristics (e.g., nutritional, metabolic, and immune status), pathogens (e.g., virulence and environmental survival), and environment (e.g., temperature, hygrometry, and water quality). The animal trade is thought to be an important cause of worldwide spread, with global modifications in temperature, hygrometry, and water quality further affecting fungal pathogenicity and host immune response.

Cross-continental emergence of Nannizziopsis barbatae disease may threaten wild Australian lizards

Members of the genus Nannizziopsis are emerging fungal pathogens of reptiles that have been documented as the cause of fatal mycoses in a wide range of reptiles in captivity. Cases of severe, proliferative dermatitis, debility and death have been detected in multiple free-living lizard species from locations across Australia, including a substantial outbreak among Eastern water dragons (Intellagama lesueurii) in Brisbane, Queensland. We investigated this disease in a subset of severely affected lizards and identified a clinically consistent syndrome characterized by hyperkeratosis, epidermal hyperplasia, dermal inflammation, necrosis, ulceration, and emaciation. Using a novel fungal isolation method, histopathology, and molecular techniques, we identified the etiologic agent as Nannizziopsis barbatae, a species reported only once previously from captive lizards in Australia. Here we report severe dermatomycosis caused by N. barbatae in five species of Australian lizard, representing the first cases of Nannizziopsis infection among free-living reptiles, globally. Further, we evaluate key pathogen and host characteristics that indicate N. barbatae-associated dermatomycosis may pose a concerning threat to Australian lizards.

Outbreak of Paranannizziopsis australasiensis Infection in Captive African Bush Vipers (Atheris squamigera)

We report the epidemiological, clinical and pathological features of an outbreak of Paranannizziopsis australasiensis (order Onygenales) in captive African bush vipers (Atheris squamigera) (ABVs) that died suddenly. The snakes had multifocal, raised, white-grey to dark brown discoloured cutaneous patches. Microscopically, all had integumentary lesions characterized by multifocal to coalescent necroheterophilic epidermitis with superficial and intraepidermal fungal elements and bacteria. Concurrent epidermal hyperplasia, hyperkeratosis and intracellular and intercellular oedema, often leading to vesiculation, and fasciitis/superficial myositis, were consistent findings in all snakes, while ulceration (9/11) and dysecdysis (5/11) varied. A panfungal polymerase chain reaction targeting the internal transcribed spacer-2 region, and gene sequencing, confirmed P. australasiensis infection in three cases. This is the first report of P. australasiensis in the USA and the first record of paranannizziopsis infection in African bush vipers. P. australasiensis should be considered in the differential diagnosis of dermatomycosis in snakes and represents a potential threat to reptile conservation programmes.

Emydomyces testavorans, a New Genus and Species of Onygenalean Fungus Isolated from Shell Lesions of Freshwater Aquatic Turtles

The fungal order Onygenales includes many pathogens of humans and animals, and recent studies have shown some onygenalean fungi to be significant emerging pathogens of reptiles. Although many of these fungi have similar morphological features in histologic tissue sections, recent molecular analyses have revealed a genetically complex and diverse group of reptile pathogens comprising several genera, most notably Nannizziopsis, Ophidiomyces, and Paranannizziopsis Infections by members of these genera have been previously reported in a variety of reptile species, including crocodilians, lizards, snakes, and tuataras, with negative impacts on conservation efforts for some reptiles. Despite the well-documented pathogenicity of these fungi in all other extant reptile lineages, infection has not yet been reported in aquatic turtles. In this study, we report the isolation of an onygenalean fungus associated with shell lesions in freshwater aquatic turtles. The morphologic and genetic characteristics of multiple isolates (n = 21) are described and illustrated. Based on these features and results of a multigene phylogenetic analysis, a new genus and species, Emydomyces testavorans, are proposed for these fungi isolated from turtle shell lesions.

Novel Paranannizziopsis species in a Wagler's viper (Tropidolaemus wagleri), tentacled snakes (Erpeton tentaculatum), and a rhinoceros snake (Rhynchophis boulengeri) in a zoological collection

We report several cases of fungal infections in snakes associated with a new species within the genus Paranannizziopsis. Three juvenile Wagler's vipers (Tropidolaemus wagleri) presented with skin abnormalities or ulcerative dermatitis, and two snakes died. Histologic examination of skin from the living viper revealed hyperplastic, hyperkeratotic, and crusting epidermitis with intralesional fungal elements. The terrestrial Wagler's vipers were housed in a room with fully aquatic tentacled snakes (Erpeton tentaculatum), among which there had been a history of intermittent skin lesions. Approximately 2 months after the biopsy of the viper, a skin sample was collected from one tentacled snake (TS1) with skin abnormalities and revealed a fungal infection with a similar histologic appearance. Fungal isolates were obtained via culture from the Wagler's viper and TS1 and revealed a novel species, Paranannizziopsis tardicrescens, based on phenotypic characterization and molecular analysis. P. tardicrescens was cultured and identified by DNA sequence analysis 8 months later from a dead tentacled snake in an exhibit in an adjacent hallway and 13 months later from a living rhinoceros snake (Rhynchophis boulengeri) with two focal skin lesions. Antifungal susceptibility testing on three of four cultured isolates demonstrated potent in vitro activity for terbinafine and voriconazole.

Dermatological conditions of farmed Crocodilians: A review of pathogenic agents and their proposed impact on skin quality

The control of pathogens that target crocodilian skin is essential to the long-term success and sustainability of intensive farming operations worldwide. To understand the impact these pathogens may have on the skin, a brief overview of skin histology is given. A review of the known viral, bacterial, fungal and helminth taxa associated with skin conditions in commercially significant crocodilian species is presented. Best management practices are discussed, with an emphasis on addressing extrinsic factors that influence transmission and pathogenicity. It is argued that, in the past, reduced immune function arising from inadequate thermal regulation was the leading cause of skin disease in captive crocodilians. Consequently, innovations such as temperature control, coupled with the adoption of more stringent hygiene standards, have greatly reduced the prevalence of many infectious skin conditions in intensively farmed populations. However, despite improvements in animal husbandry and disease management, viral pathogens such as West Nile virus, herpesvirus and poxvirus continue to afflict crocodilians in modern captive production systems.

Disseminated Nannizziopsis obscura infection in a renal transplant patient- The first reported case

This is a presentation of a case of disseminated fungal infection in a renal transplant patient with Nannizziopsis obscura, a species not previously reported as having caused disseminated disease in humans and not previously reported in the UK. The fungus was isolated from a intramuscular collection and from a lymph node. The patient responded well to a course of posaconazole.

Nannizziopsis guarroi infection in 2 Inland Bearded Dragons (Pogona vitticeps): clinical, cytologic, histologic, and ultrastructural aspects

Chrysosporium-related infections have been increasingly reported in reptiles over the last 2 decades. In this report, we describe clinical, cytologic, histopathologic, and ultrastructural aspects of Chrysosporium-related infection in 2 Inland Bearded Dragons (Pogona vitticeps). Case 1 was presented for an enlarging raised lesion over the left eye and multiple additional masses over the dorsum. Case 2 was submitted to necropsy by the referring veterinarian for suspected yellow fungus disease. Impression smears of the nodules in case 1 revealed granulomatous to pyogranulomatous inflammation and many septate, variably long, 4-10 μm wide, often undulated hyphae, and very rare conidia. Postmortem impression smears of the superficial lesions of case 2 contained large numbers of solitary conidia and arthroconidia and low numbers of hyphae with similar morphology to case 1. Histopathology of the 2 cases revealed severe, multifocal, chronic, ulcerative, nodular pyogranulomatous dermatitis, with myriad intralesional septate hyphae, and arthroconidia. Fungal culture and molecular sequencing in both cases indicated infection with Nannizziopsis guarroi.

Ophidiomyces ophiodiicola dermatitis in eight free-ranging timber rattlesnakes (Crotalus horridus) from Massachusetts

Eight free-ranging timber rattlesnakes (Crotalus horridus) from two geographically isolated Massachusetts populations were observed with skin lesions located primarily on the head but occasionally also on the lateral and ventral surfaces of the body. The snakes underwent health assessments that included physical examination, clinical pathology, full body radiographs, and full thickness biopsies of skin lesions. Each snake had fungal elements present histologically in tissue sections from skin lesions. Ophidiomyces ophiodiicola was identified from skin lesions using polymerase chain reaction in all eight snakes.

Molecular characterization of reptile pathogens currently known as members of the chrysosporium anamorph of Nannizziopsis vriesii complex and relationship with some human-associated isolates

In recent years, the Chrysosporium anamorph of Nannizziopsis vriesii (CANV), Chrysosporium guarroi, Chrysosporium ophiodiicola, and Chrysosporium species have been reported as the causes of dermal or deep lesions in reptiles. These infections are contagious and often fatal and affect both captive and wild animals. Forty-nine CANV isolates from reptiles and six isolates from human sources were compared with N. vriesii based on their cultural characteristics and DNA sequence data. Analyses of the sequences of the internal transcribed spacer and small subunit of the nuclear ribosomal gene revealed that the reptile pathogens and human isolates belong in well-supported clades corresponding to three lineages that are distinct from all other taxa within the family Onygenaceae of the order Onygenales. One lineage represents the genus Nannizziopsis and comprises N. vriesii, N. guarroi, and six additional species encompassing isolates from chameleons and geckos, crocodiles, agamid and iguanid lizards, and humans. Two other lineages comprise the genus Ophidiomyces, with the species Ophidiomyces ophiodiicola occurring only in snakes, and Paranannizziopsis gen. nov., with three new species infecting squamates and tuataras. The newly described species are Nannizziopsis dermatitidis, Nannizziopsis crocodili, Nannizziopsis barbata, Nannizziopsis infrequens, Nannizziopsis hominis, Nannizziopsis obscura, Paranannizziopsis australasiensis, Paranannizziopsis californiensis, and Paranannizziopsis crustacea. Chrysosporium longisporum has been reclassified as Paranannizziopsis longispora. N. guarroi causes yellow fungus disease, a common infection in bearded dragons and green iguanas, and O. ophiodiicola is an emerging pathogen of captive and wild snakes. Human-associated species were not recovered from reptiles, and reptile-associated species were recovered only from reptiles, thereby mitigating concerns related to zoonosis.

Chrysosporium anamorph Nannizziopsis vriesii: an emerging fungal pathogen of captive and wild reptiles

Chrysosporium anamorph Nannizziopsis vriesii is a recent pathogen associated with infections in lizards, snakes, and crocodilians. It seems to be an obligate pathogen. It has been isolated from wild reptiles in addition to captive animals. Affected animals often present with aggressive, pyogranulomatous lesions that can affect the integument and musculoskeletal systems. Diagnosis can be done using culture, histopathology, and polymerase chain reaction assay. Ancillary diagnostic tests can be useful in characterizing the health status of the affected reptile and aid in planning supportive care and therapy. Treatment using antifungals has shown mixed results.

Phylogeny of chrysosporia infecting reptiles: proposal of the new family Nannizziopsiaceae and five new species

We have performed a phenotypic and phylogenetic study of a set of fungi, mostly of veterinary origin, morphologically similar to the Chrysosporium asexual morph of Nannizziopsis vriesii (Onygenales, Eurotiomycetidae, Eurotiomycetes, Ascomycota). The analysis of sequences of the D1-D2 domains of the 28S rDNA, including representatives of the different families of the Onygenales, revealed that N. vriesii and relatives form a distinct lineage within that order, which is proposed as the new family Nannizziopsiaceae. The members of this family show the particular characteristic of causing skin infections in reptiles and producing hyaline, thin- and smooth-walled, small, mostly sessile 1-celled conidia and colonies with a pungent skunk-like odour. The phenotypic and multigene study results, based on ribosomal ITS region, actin and β-tubulin sequences, demonstrated that some of the fungi included in this study were different from the known species of Nannizziopsis and Chrysosporium and are described here as new. They are N. chlamydospora, N. draconii, N. arthrosporioides, N. pluriseptata and Chrysosporium longisporum. Nannizziopsis chlamydospora is distinguished by producing chlamydospores and by its ability to grow at 5 °C. Nannizziopsis draconii is able to grow on bromocresol purple-milk solids-glucose (BCP-MS-G) agar alkalinizing the medium, is resistant to 0.2 % cycloheximide but does not grow on Sabouraud dextrose agar (SDA) with 3 % NaCl. Nannizziopsis arthrosporioides is characterised by the production of very long arthroconidia. Nannizziopsis pluriseptata produces 1- to 5-celled sessile conidia, alkalinizes the BCP-MS-G agar and grows on SDA supplemented with 5 % NaCl. Chrysosporium longisporum shows long sessile conidia (up to 13 μm) and does not produce lipase.

Phaeohyphomycoses, emerging opportunistic diseases in animals

Emerging fungal diseases due to black yeasts and relatives in domestic or wild animals and in invertebrates or cold- and warm-blooded vertebrates are continually being reported, either as novel pathogens or as familiar pathogens affecting new species of hosts. Different epidemiological situations can be distinguished, i.e., occurrence as single infections or as zoonoses, and infection may occur sporadically in otherwise healthy hosts. Such infections are found mostly in mammals but also in cold-blooded animals, are frequently subcutaneous or cerebral, and bear much similarity to human primary disorders. Infections of the nervous system are mostly fatal, and the source and route of infection are currently unknown. A third epidemiological situation corresponds to pseudoepidemics, i.e., infection of a large host population due to a common source. It is often observed and generally hypothesized that the susceptible animals are under stress, e.g., due to poor housing conditions of mammals or to a change of basins in the case of fishes. The descriptions in this article represent an overview of the more commonly reported and recurring black fungi and the corresponding diseases in different types of animals.

Dermatitis and cellulitis in leopard geckos (Eublepharis macularius) caused by the Chrysosporium anamorph of Nannizziopsis vriesii

An epizootic of ulcerative to nodular ventral dermatitis was observed in a large breeding colony of 8-month to 5-year-old leopard geckos (Eublepharis macularius) of both sexes. Two representative mature male geckos were euthanized for diagnostic necropsy. The Chrysosporium anamorph of Nannizziopsis vriesii (CANV) was isolated from the skin lesions, and identification was confirmed by sequencing of the internal transcribed spacer region of the rRNA gene. Histopathology revealed multifocal to coalescing dermal and subcutaneous heterophilic granulomas that contained septate fungal hyphae. There was also multifocal epidermal hyperplasia with hyperkeratosis, and similar hyphae were present within the stratum corneum, occasionally with terminal chains of arthroconidia consistent with the CANV. In one case, there was focal extension of granulomatous inflammation into the underlying masseter muscle. This is the first report of dermatitis and cellulitis due to the CANV in leopard geckos.

Deep fungal dermatitis caused by the Chrysosporium anamorph of Nannizziopsis vriesii in captive coastal bearded dragons (Pogona barbata)

Deep fungal dermatitis caused by the Chrysosporium anamorph of Nannizziopsis vriesii (CANV) was diagnosed in a group of coastal bearded dragons (Pogona barbata). The outbreak extended over a 6-month period, with four of six lizards from the same zoological outdoor enclosure succumbing to infection. A fifth case of dermatomycosis was identified in a pet lizard originally sourced from the wild. Diagnosis of infection with the CANV was based on similar clinical signs and histopathology in all animals and confirmed by culture and sequencing of the fungus from one animal. This is the first report of the CANV causing disease in a terrestrial reptile species in Australia and the first in the coastal bearded dragon.

Waterborne Exophiala species causing disease in cold-blooded animals

The majority of mesophilic waterborne species of the black yeast genus Exophiala (Chaetothyriales) belong to a single clade judging from SSU rDNA data. Most taxa are also found to cause cutaneous or disseminated infections in cold-blooded, water animals, occasionally reaching epidemic proportions. Hosts are mainly fish, frogs, toads, turtles or crabs, all sharing smooth, moist or mucous skins and waterborne or amphibian lifestyles; occasionally superficial infections in humans are noted. Cold-blooded animals with strictly terrestrial life styles, such as reptiles and birds are missing. It is concluded that animals with moist skins, i.e. those being waterborne and those possessing sweat glands, are more susceptible to black yeast infection. Melanin and the ability to assimilate alkylbenzenes are purported general virulence factors. Thermotolerance influences the choice of host. Exophiala species in ocean water mostly have maximum growth temperatures below 30 °C, whereas those able to grow until 33(−36) °C are found in shallow waters and occasionally on humans. Tissue responses vary with the phylogenetic position of the host, the lower animals showing poor granulome formation. Species circumscriptions have been determined by multilocus analyses involving partial ITS, TEF1, BT2 and ACT1.

Voriconazole, a safe alternative for treating infections caused by the Chrysosporium anamorph of Nannizziopsis vriesii in bearded dragons (Pogona vitticeps)

Dermal and systemic infections caused by the Chrysosporium anamorph of Nannizziopsis vriesii (CANV) are highly prevalent in reptiles and may result in severe disease and high mortality. Due to the high incidence of therapeutic failures, optimizing treatment is required. We first determined in this study the minimal inhibitory concentrations (MIC) of itraconazole, voriconazole, amphotericin B and terbinafine against 32 CANV isolates. For voriconazole, amphotericin B and terbinafine a monomodal MIC distribution was seen, whereas a bimodal MIC distribution was present for itraconazole, indicating acquired resistance in one isolate. Fourteen naturally-infected bearded dragons (Pogona vitticeps), from the same owner, were treated orally with either itraconazole (5 mg/kg q24h) or voriconazole (10 mg/kg q24h). The clinical condition, drug plasma concentrations and the presence of CANV in skin samples were followed. The animals were treated until complete clearance of the fungus. The plasma concentrations of voriconazole and itraconazole exceeded the minimal inhibitory concentrations of the CANV isolates. Elimination of CANV was achieved on average after 27 and 47 days of treatment with itraconazole and voriconazole, respectively. Whereas only 2 out of 7 survived after itraconazole treatment, only a single animal died in the voriconazole treated group. In conclusion, based on a limited number of animals, voriconazole applied at a regimen of 10 mg/kg bodyweight (BW) q24h seems to be a safe and effective antimycotic drug to eliminate CANV infections in bearded dragons.

Cutaneous hyalohyphomycosis in a girdled lizard (Cordylus giganteus) caused by the Chrysosporium anamorph of Nannizziopsis vriesii and successful treatment with voriconazole

The Chrysosporium anamorph of Nannizziopsis vriesii was associated with dermatomycosis and high mortality in a group of captive giant girdled lizards (Cordylus giganteus). Treatment of one of the infected girdled lizards with voriconazole, which was selected on the basis of in vitro sensitivity testing of the isolate, resulted in resolution of lesions and negative fungal cultures from the skin. Three hours after oral administration of 10 mg/kg, the plasma level of voriconazole exceeded the 0.25-μg/mL minimal inhibitory concentration tenfold. In conclusion, administration of voriconazole at 10 mg/kg of body weight once daily for 10 weeks resulted in clinical cure and was well tolerated. A longer follow-up time and larger studies will be necessary to determine the long-term efficacy and safety of this treatment in giant girdled lizards.

Dermatomycosis in a pet inland bearded dragon (Pogona vitticeps) caused by a Chrysosporium species related to Nannizziopsis vriesii

A Chrysosporium sp. related to Nannizziopsis vriesii was isolated in pure culture from squames and biopsies of facial lesions in a pet inland bearded dragon (Pogona vitticeps) in Spain. The presence in histological sections of morphologically consistent fungal elements strongly incriminates this fungus as the aetiological agent of infection. Lesions regressed following treatment with oral ketoconazole and topical chlorhexidine and terbinafine until the lizard was lost to follow up 1 month later. The ITS-5.8S rRNA gene of the isolate was sequenced and a search on the GenBank database revealed a high match with the sequences of two Chrysosporium sp. strains recently isolated from green iguanas (Iguana iguana) with dermatomycosis, also in Spain. Phylogenetic analysis of the sequences revealed that all these strains are related to N. vriesii. This is the first report of dermatomycoses caused by a Chrysosporium species related to N. vriesii in a bearded dragon outside North America.

CROCODILIANS

This chapter presents a general overview of the anatomy, physiology, and treatment methodology for crocodilians. Most crocodilians grow to be larger than other reptile species and, therefore, have significant space requirements. Like most animals requiring an aquatic environment, crocodilians need water that is clean and free of disease. Crocodilians have a true hard palate in the roof of the mouth that ends caudally in a soft palate. This soft palate has a ventral flap which is referred to as the velum palati. The respiratory system of crocodilians consists of well-developed lungs benefiting from a very effective inspiration aided by the intercostal muscles and the septum post hepaticum. Crocodilians have a four-chambered heart as opposed to the three-chambered heart found in other reptiles and amphibians. The temperature and humidity requirements for crocodilians in captivity vary with the species. An understanding of crocodilian biology and natural history is needed to try and duplicate their natural environment. An important consideration is the allowance of circadian variations in light cycle and temperatures to mimic their natural environment. This is not the case in many commercial operations, where they are maintained at a fairly constant temperature and humidity to achieve faster growth.

Isolation and characterization of a new fungal species, Chrysosporium ophiodiicola, from a mycotic granuloma of a black rat snake (Elaphe obsoleta obsoleta)

Isolation and characterization of the new species Chrysosporium ophiodiicola from a mycotic granuloma of a black rat snake (Elaphe obsoleta obsoleta) are reported. Analysis of the sequences of different fragments of the ribosomal genes demonstrated that this species belongs to the Onygenales and that this species is genetically different from other morphologically similar species of Chrysosporium. This new species is unique in having both narrow and cylindrical-to-slightly clavate conidia and a strong, pungent odor.

Deep fungal dermatitis in three inland bearded dragons (Pogona vitticeps) caused by the Chrysosporium anamorph of Nannizziopsis vriesii

The Chrysosporium anamorph of Nannizziopsis vriesii (CANV), a keratinophilic fungus that naturally and experimentally causes severe and often fatal dermatitis in multiple reptile species, was isolated in pure culture from skin samples of three inland bearded dragons (Pogona vitticeps) with deep granulomatous dermatomycosis. The first animal presented with a focal maxillary swelling involving the skin and gingiva. This lizard died while undergoing itraconazole and topical miconazole therapy. The second presented with focally extensive discoloration and thickening of the skin of the ventrum and was euthanized after 10 weeks of itraconazole therapy. A third lizard presented with hyperkeratotic exudative dermatitis on a markedly swollen forelimb. Amputation and itraconazole therapy resulted in a clinical cure. Histopathology of tissue biopsies in all cases demonstrated granulomatous dermatitis with intralesional hyphae morphologically consistent with those produced by the CANV. The second lizard also had granulomatous hepatitis with intralesional hyphae. Evidence in this report suggests that the CANV is the etiologic agent of an emerging condition in captive bearded dragons that has been called 'yellow fungus disease'.

Pathogenicity of the Chrysosporium anamorph of Nannizziopsis vriesii for veiled chameleons (Chamaeleo calyptratus)

Veiled chameleons (Chamaeleo calyptratus) were experimentally challenged with the fungus Chrysosporium anamorph of Nannizziopsis vriesii (CANV). Chameleons were exposed to conidia in their captive environment, or were inoculated by direct application of a conidial suspension inoculum on intact and on abraded skin. The CANV induced lesions in all experimental groups and was recovered from infected animals, fulfilling Koch's postulates and confirming that it may act as a primary fungal pathogen in this species of reptile. A breach in cutaneous integrity, as simulated by mild scarification, increased the risk of infection but was not required for the CANV to express pathogenicity. Initial hyphae proliferation occurred in the outer epidermal stratum corneum, with subsequent invasion of the deeper epidermal strata and dermis. A spectrum of lesions was observed ranging from liquefactive necrosis of the epidermis to granulomatous inflammation in the dermis. CANV dermatomycosis appears to be contagious and can readily spread within a reptile collection, either directly through contact with infective arthroconidia or indirectly via fomites. Dense tufts of arthroconidiating hyphae were demonstrated histologically on the skin surface of many animals that developed dermatomycosis, and these arthroconidia may act as infective propagules involved in the transfer of disease between reptiles.

False-positive Histoplasma capsulatum Gen-Probe chemiluminescent test result caused by a Chrysosporium species

We describe a case in which the Histoplasma capsulatum AccuProbe test displayed cross-reactivity with a respiratory isolate thought to be Histoplasma but not morphologically consistent with H. capsulatum. The isolate was later identified as the Chrysosporium anamorph of Nannizziopsis vriesii by sequence analysis and phenotypic data.