Paracoccidioidomycosis ceti (PCM-C) is a chronic granulomatous keloidal dermatitis in cetaceans that has been reported worldwide and is caused by Paracoccidioides ceti. Serological cross-reactions among highly pathogenic fungal infections and related diseases have been reported. However, the true cross-reaction of antibodies against P. ceti has remained unknown due to the use of positive control sera from infected dolphins. This study aimed to re-evaluate antibodies from mechanically dislodged fungal cells in the infected tissue of a PCM-C case and demonstrate the actual cross-reaction. The results revealed a limited cross-reaction between PCM-C and paracoccidioidomycosis, while the antibodies did not react with other pathogens such as Coccidioides posadasii, Histoplasama capsulatum, and Arthrographis kalrae. Thus, the method for evaluation of the antibody against PCM-C is reliable, and there is potential for epidemiological study.

Paracoccidiodomycosis ceti (PCM-C) is a zoonotic mycosis characterized by chronic granulomatous cutaneous lesions in cetaceans. It is distributed worldwide and is caused by an unculturable fungus; Paracoccidioides cetii. On the other hand, coccidioidomycosis (CCM), caused by Coccidioides spp., is also a zoonotic and highly pathogenic fungal infection endemic in both American continents. Even though the Far East is not an endemic area of CCM, an autochthonous case has been reported in China. Although the seroprevalence against P. cetii in captive dolphins was 61.0%, there is no information on wild dolphins living in cold waters. The present study aimed to investigate the seroprevalence against P. cetii and C. posadasii in 15 Dall\'s porpoises (Phocoenoides dalli) and 11 harbor porpoises (Phocoena phocoena) stranded in Hokkaido, Japan. The seroprevalence against P. cetii in the above dolphins was 26.9% (7/26), which was recorded only in Dall\'s porpoises (7/15), and that against C. posadasii was 15.4% (4/26), three in Dall\'s porpoises and one in harbor porpoise. The present study demonstrated positive seroprevalence against P. cetii and C. posadasii in wild cetaceans living in the subarctic areas of the Far East as the first records, and would issue the warning those who live in the area were exposed to the causative agent of CCM from seawater.

The skin disease paracoccidioidomycosis ceti occurs in several dolphin species globally. Infection by the unculturable fungi Paracoccidioides brasilensis or other Paracoccidioides spp. results in chronic cutaneous and granulomatous lesions. In this study we used immunohistochemistry to investigate the seroprevalence of antibodies to Paracoccidioides spp. in captive dolphins from three aquaria in Japan. We had previously reported that there were serological cross-reactions for Paracoccidioides spp. with related species in the order Onygenales. We hypothesized that the degree of serological cross-reactions for Paracoccidioides spp. might be lower in areas, such as Japan, where the fungal diseases coccidiodomycosis and paracoccidiodomycosis are not endemic. Sera from 41 apparently healthy dolphins, including 20 Atlantic bottlenose dolphins (BD: Tursiops truncatus), 6 Indo-Pacific bottlenose dolphins (IPBD: Tursiops aduncus), 2 F1 generation of a cross between BD and IPBD (F1), 3 Pacific white-sided dolphins (PWD: Lagenorhynchus obliquidens), 2 pantropical spotted dolphins (PSD: Stenella attenuata), 6 false killer whales (FKW: Pseudorca crassidens), and 2 rough-toothed dolphins (RTD: Steno bredanensis) were investigated. Sera from three dolphins with paracoccidioidomycosis ceti were used as a positive control. The yeast-form cells of Paracoccidioides spp. in the cutaneous tissue sample derived from the first Japanese paracoccidioidomycosis ceti case were used as the antigen for the immunohistochemistry. Of the 41 dolphins tested, 61.0% had antibodies against Paracoccidioides spp. This indicates that dolphins of several species in Japanese aquaria have likely been exposed to the pathogen Paracoccidioides spp.

The prominence of seafood in Japan motivates close monitoring of its seas and marine lives for potentially pathogenic fungi. During the treatments of the male Pacific white-sided dolphin (Lagenorhynchus obliquidens) for paracoccidioidomycosis ceti (PCM-C), 5 white and floccose colonies showing identical genotype and morphological characteristics were isolated from two skin biopsy samples of cutaneous granulomatous lesions in 2018. The isolates were identified as Parengyodontium album known as one of fungal species having abilities to produce industrially important proteases, and to become a causative agent for emerging mycosis based on morphological and molecular biological characteristics. These lesions consisted of non-malignant pearl-like structures of hyperplastic keratinocytes. Interestingly, although the isolates could grow at 35 °C, their DNA sequences were phylogenetically located in a cluster consisting of environmental and clinical isolates lacking the ability to grow at 35 °C, based on previous reports. The opportunistic infection we observed in the dolphin might be caused by immune disorder due to PCM-C. Notably, although P. album is recognized as non-harmful, and has significant industrial importance and antitumor activity, it has potential to cause not only superficial but also systemic infection, and presents difficulties in treatment because of its high resistance to antifungal compounds.

Recently, we have reported serological cross-reactivity between paracoccidioidomycosis ceti and paracoccidioidomycosis, histoplasmosis, and coccidioidomycosis. However, data on the interaction of Arthrographis kalrae with the above pathogenic fungal infections are lacking. A. kalrae is a widely occurring ascomycetous fungus; causes superficial and deep mycoses; shows thermally dependent dimorphism; and has a genomic profile related to the above-mentioned fungal species. Our study aims to investigate cross-reactivity using eight murine sera, obtained from experimental infection with two A. kalrae isolates. The murine sera were incubated with fungal cells of A. kalrae, Coccidioides posadasii, Histoplasma capsulatum, Paracoccidioides sp., and P. brasiliensis. Thirty murine sera, obtained from experimental infection with six isolates of H. capsulatum, sera from three cases of dolphin paracoccidioidomycosis ceti, two human sera from patients with paracoccidioidomycosis, and a serum sample from a healthy person with a history of coccidioidomycosis, were also incubated with A. kalrae fungal cells and the respective fungal cells that caused the infection as positive controls. Sera derived from the mice infected with A. kalrae reacted strongly when incubated with the Paracoccidioides sp., P. brasiliensis, and C. posadasii, but no positive reaction was observed against the fungal cells of H. capsulatum. The murine sera infected with three out of six isolates of H. capsulatum, and all cetacean and human serum samples reacted positively with the fungal cells of A. kalrae. The present study demonstrated serological cross-reactions among A. kalrae infection, coccidioidomycosis, paracoccidioidomycosis, paracoccidioidomycosis ceti, and histoplasmosis.

Paracoccidioidomycosis ceti is a cutaneous disease of cetaceans caused by uncultivated Paracoccidioides brasiliensis or Paracoccidioides spp. Serological cross-reactions between paracoccidioidomycosis ceti and paracoccidioidomycosis, paracoccidioidomycosis and histoplasmosis, and paracoccidioidomycosis and coccidioidomycosis have been reported before. The present study aimed to detect immunohistochemical cross-reaction between antibodies to Paracoccidioides sp. and Histoplasma capsulatum, and vice versa. Thirty murine sera, obtained from experimental infections of 6 isolates of H. capsulatum, were reacted with paraffin-embedded yeast-form cells of Paracoccidioides sp. derived from a case of paracoccidioidomycosis ceti in Japan. The murine sera were also reacted with human isolates of H. capsulatum yeast cells, with P. brasiliensis yeast cells, and with fungal cells of Coccidioides posadasii. Three dolphins\' sera from cases of paracoccidioidomycosis ceti, two human sera from patients with paracoccidioidomycosis, and a serum from a healthy person with a history of coccidioidomycosis were used in order to determine that the tested fungal cells reacted properly. Sera derived from mice infected with an isolate of H. capsulatum reacted positively against yeast cells of Paracoccidioides sp., yeast cells of P. brasiliensis, and fungal cells of C. posadasii, while those derived from other strains were negative. The present study recorded for the first time the cross-reaction between the yeast cells of H. capsulatum and antibodies against Paracoccidioides spp., the yeast cells of Paracoccidioides sp. and antibodies against H. capsulatum, the yeast cells of Paracoccidioides sp. and antibodies against Coccidioides sp., and fungal cells of C. posadasii and antibodies against Paracoccidioides spp.

From 2003 to 2015, 360 free-ranging Atlantic bottlenose dolphins Tursiops truncatus inhabiting the Indian River Lagoon (IRL, n = 246), Florida, and coastal waters of Charleston (CHS, n = 114), South Carolina, USA, were captured, given comprehensive health examinations, and released as part of a multidisciplinary and multi-institutional study of individual and population health. The aim of this review is to summarize the substantial health data generated by this study and to examine morbidity between capture sites and over time. The IRL and CHS dolphin populations are affected by complex infectious and neoplastic diseases often associated with immunologic disturbances. We found evidence of infection with cetacean morbillivirus, dolphin papilloma and herpes viruses, Chlamydiaceae, a novel uncultivated strain of Paracoccidioides brasiliensis (recently identified as the causal agent of dolphin lobomycosis/lacaziasis), and other pathogens. This is the first long-term study documenting the various types, progression, seroprevalence, and pathologic interrelationships of infectious diseases in dolphins from the southeastern USA. Additionally, the study has demonstrated that the bottlenose dolphin is a valuable sentinel animal that may reflect environmental health concerns and parallel emerging public health issues.

\"Paracoccidioidomycosis ceti\" is a rare zoonotic fungal infection affecting dolphins and is endemic worldwide. The causative agents are Paracoccidioides species; however, it is impossible to isolate the fungal species. We isolated Trichosporon asteroides from multifocal, irregularly raised skin lesions on a female bottlenose dolphin (Tursiops truncatus) captured off coast of Japan, which was suspected to have \"paracoccidioidomycosis ceti.\" An abundance of round, yeast-like cells was detected in a potassium hydroxide direct-mount specimen of the skin samples; however, nested PCR targeting the partial sequence of 43-kDa glycoprotein-coding gene correspondent to Paracoccidioides sp. was negative. Biopsied tissue samples were cultured on brain heart infusion agar plates supplemented with chloramphenicol, 1% yeast extract, and 4% sodium chloride (4% NaCl-BHI), on Mycosel agar with 4% sodium chloride (4% NaCl-Mycosel), and on potato dextrose agar supplemented with chloramphenicol (CPDA) at 35 °C for 4 weeks. Cream-colored and wrinkled colonies consisting of hyphae and arthroconidia grew on 4% NaCl-BHI and CPDA, while film-like colonies composed of arthroconidia and round yeast-like cells developed on 4% NaCl-Mycosel. Although these primary cultures resembled fresh isolates of P. brasiliensis, they were identified as Trichosporon asteroides based on routine mycological studies and the internal transcribed spacer regions of ribosomal RNA sequences. The results suggested that trichosporonosis caused by T. asteroides might remain latent among cases of \"paracoccidioidomycosis ceti\" diagnosed without cultures and molecular biological analysis.

Cutaneous granulomas in dolphins were believed to be caused by Lacazia loboi, which also causes a similar disease in humans. This hypothesis was recently challenged by reports that fungal DNA sequences from dolphins grouped this pathogen with Paracoccidioides brasiliensis. We conducted phylogenetic analysis of fungi from 6 bottlenose dolphins (Tursiops truncatus) with cutaneous granulomas and chains of yeast cells in infected tissues. Kex gene sequences of P. brasiliensis from dolphins showed 100% homology with sequences from cultivated P. brasiliensis, 73% with those of L. loboi, and 93% with those of P. lutzii. Parsimony analysis placed DNA sequences from dolphins within a cluster with human P. brasiliensis strains. This cluster was the sister taxon to P. lutzii and L. loboi. Our molecular data support previous findings and suggest that a novel uncultivated strain of P. brasiliensis restricted to cutaneous lesions in dolphins is probably the cause of lacaziosis/lobomycosis, herein referred to as paracoccidioidomycosis ceti.