Madurella mycetomatis grains within a eumycetoma lesion are clonal.

Eumycetoma is a neglected tropical infection of the subcutaneous tissue, characterized by tumor-like lesions and most commonly caused by the fungus Madurella mycetomatis. In the tissue, M. mycetomatis organizes itself in grains, and within a single lesion, thousands of grains can be present. The current hypothesis is that all these grains originate from a single causative agent, however, this hypothesis was never proven. Here, we used our recently developed MmySTR assay, a highly discriminative typing method, to determine the genotypes of multiple grains within a single lesion. Multiple grains from surgical lesions obtained from 11 patients were isolated and genotyped using the MmySTR panel. Within a single lesion, all tested grains shared the same genotype. Only in one single grain from one patient, a difference of one repeat unit in one MmySTR marker was noted relative to the other grains from that patient. We conclude that within these lesions the grains originate from a single clone and that the inherent unstable nature of the microsatellite markers may lead to small genotypic differences. LAY ABSTRACT: In lesions of the implantation mycosis mycetoma many Madurella mycetomatis grains are noted. It was unknown if grains arose after implantation of a single isolate or a mixture of genetically diverse isolates. By typing the mycetoma grains we showed that all grains within a single lesion were clonal and originated from a single isolate.

Eumycetoma and disseminated phaeohyphomycosis in a Sumatran tiger.

A 16-y-old female Sumatran tiger (Panthera tigris sumatrae) was evaluated for hyporexia. Examination revealed chronic kidney disease and a large subcutaneous axillary mass with draining tracts that contained numerous small black grains. Histologic examination revealed the presence of intralesional fungal hyphae. Persistent hyporexia and pyogranulomatous disease, as well as progressive cachexia and azotemia occurred despite treatment, and euthanasia was performed. Disseminated phaeohyphomycosis was diagnosed on postmortem examination, additionally affecting various lymph nodes, the nasal cavity, mesenteric adipose tissue, abdominal aorta, pericardium, and kidney. Fungal culture from a deep-tissue sample isolated a pure growth of Curvularia sp., a dematiaceous opportunistic fungus able to cause eumycetomas and/or phaeohyphomycosis. Phaeohyphomycosis is a rare but emerging condition, not previously reported as disseminated disease in an exotic carnivore, to our knowledge. Aggressive systemic antifungal treatment was unsuccessful, likely complicated by diagnostic challenges and concurrent renal disease. The presence of a swelling with abundant grains exiting draining tracts should direct clinicians to the diagnosis of a mycetoma, warranting early and aggressive treatment.

Successful medical treatment of an Aspergillus terreus mycetoma of the nostril/lip in a 16-year-old Fjord pony gelding with pituitary pars intermedia dysfunction.

BACKGROUND: Mycetoma is a chronic, proliferative lesion of cutaneous/subcutaneous tissue characterized by draining tracts and granules in the discharge caused by actinomycetes (actinomycetoma) or filamentous fungi (eumycotic mycetoma). OBJECTIVES: This case report describes the unusual finding of a cutaneous mycetoma of the lateral wing of the right nostril in a gelding. ANIMAL: A 16-year-old Fjord gelding with suspected pituitary pars intermedia dysfunction (PPID) was presented for evaluation of a nonpainful, firm and raised mass involving the lateral wing of the right nostril and the lip. METHODS AND RESULTS: Cytological examination of the mass showed marked pyogranulomatous inflammation and histopathological examination revealed a fungal mycetoma. Fungal culture identified the causative organism as Aspergillus terreus, which is not known for its propensity to cause either dermal granulomas or mycetoma in domestic animals. Further investigation, including a TRH stimulation test, led to a diagnosis of PPID (Cushing's disease), which may have led to immunosuppression of the animal and increased susceptibility to infection. CONCLUSIONS AND CLINICAL IMPORTANCE: The horse was treated medically with pergolide for the PPID and oral potassium iodide for the fungal infection, with good therapeutic response and no relapse after five months. Surgical debridement or excision was not performed. To the best of the authors' knowledge, this is the first case report of a cutaneous mycetoma caused by A. terreus in a horse.

Successful treatment of intra-abdominal eumycotic mycetoma caused by Penicillium duponti in a dog.

A 2-year-old female neutered golden retriever was presented for investigation of an intra-abdominal mass. Computed tomography revealed a mass associated with the caudal pole of the right kidney. Incisional biopsy findings were consistent with eumycotic mycetoma. The mass was subsequently removed in conjunction with right ureteronephrectomy. Two years later, the dog re-presented with a splenic mass and fungal plaques located throughout the peritoneum. Splenectomy was performed and the mass was diagnosed as eumycotic mycetoma caused by Penicillium duponti. Indefinite systemic treatment with 10 mg/kg itraconazole orally once a day was initiated. Thirty-two months after the last surgery, there were no clinical signs apart from mild polydipsia. Haematology and biochemistry results were unremarkable. To the authors' knowledge, this is the first report of successful treatment of intra-abdominal eumycotic mycetoma with a combination of surgery and systemic antifungal therapy in the dog. Penicillium duponti has not apparently been reported to cause disease in animals or humans.

Variable antibiotic susceptibility patterns among Streptomyces species causing actinomycetoma in man and animals.

BACKGROUND: Drug therapy is recommended in conjunction with surgery in treatment of actinomycetoma. The specific prescription depends on the type of bacteria (actinomycetoma) or fungi (eumycetoma) causing the disease and their in vitro antimicrobial susceptibility. OBJECTIVES: To investigate the antimicrobial susceptibility among isolates of Streptomyces spp. isolated from cases of actinomycetoma in man and animals in Sudan. METHODS: Streptomyces strains (n = 18) isolated from cases of actinomycetoma were tested in vitro against 15 commonly prescribed antibacterial agents using MIC agar dilution method as per standard guidelines. RESULTS: Streptomyces strains isolated from actinomycetoma fall into various phenotypic groups. All of the strains were inhibited by novobiocin (8 µg/mL), gentamycin (8, 32 µg/mL) and doxycycline (32 µg/mL). Fusidic acid (64 µg/mL) inhibited 94.4% of the strains; bacitracin, streptomycin, cephaloridine, clindamycin, ampicillin, rifampicin and tetracycline (64 µg/mL) inhibited between 61.1 and 77.8% of the strains. All strains were found resistant to amphotericin B (64 µg/mL), penicillin (20 µg/mL) and sulphamethoxazole (64 µg/mL). CONCLUSIONS: Saprophytic Streptomyces spp. cause actinomycetoma in man and animal belong to separate phenotypes and have a wide range of susceptibility patterns to antimicrobial agents, which pose a lot of difficulties in selecting effective in vivo treatment for actinomycetoma.

Subconjunctival mycetoma caused by Scedosporium apiospermum infection in a horse.

An 11-year-old American Saddlebred gelding was presented for evaluation of a nonpainful subconjunctival mass involving the lateral canthus of the left eye. Other findings included a central corneal scar and a small central cataract of the lens in the left eye. Fine-needle aspiration of the mass was performed and cytologic examination revealed marked pyogranulomatous inflammation with intralesional fungal hyphae, consistent with mycetoma. The fungal structures were elongated and characterized by nonstaining walls; several bulbous yeast-like structures were also observed. The mycetoma was surgically removed and submitted for histopathologic examination and fungal culture. The histopathologic diagnosis was subconjunctival phaeohyphomycosis. Scedosporium apiospermum was identified based on macroscopic and microscopic features of the organism in culture. Scedosporium spp. have been reported as causes of mycetomatous and nonmycetomatous infections in both immunocompromised and immunocompetent people and animals. S. apiospermum and Pseudallescheria boydii, which is its teleomorphic counterpart, have been implicated as potentially emerging human and veterinary pathogens. Timely diagnosis is essential as the organism is often resistant to commonly used antifungal drugs. This report provides a detailed cytologic description of the organism and recent information on the taxonomy of this fungus and the diagnostic peculiarities of this particular infection.

Intra-abdominal actinomycetoma in a cat.

A 5-year-old, female Ragdoll cat was diagnosed with an intra-abdominal mycetoma involving the ileocaecal region. Diagnosis was obtained via histopathological examination following surgical resection of the mass and an ileocolic anastomosis. The initial surgery was complicated by lymphangiectasia, chylous abdominal effusion and mild bacterial leakage from the anastomosis site. A second, exploratory laparotomy was performed to augment the anastomosis with serosal patching and omentalisation and to investigate a cystic structure observed on follow-up abdominal ultrasound. Initial amoxycillin clavulanate (Clavulox; Pfizer Animal Health) therapy was ineffective, but clindamycin (Antirobe; Pfizer Animal Health) proved successful in resolving the infection. Abdominal actinomycetoma in the cat may be an under-diagnosed condition due to its close resemblance to neoplastic disease. Standard diagnostic and therapeutic regimens are commonly ineffective in Actinomyces species infections. Surgical resection along with adjunctive, long-term, selective antimicrobial therapy is effective and prognosis is good for localised lesions.

Imaging diagnosis--sublumbar pseudomycetoma in a Persian cat.

A 6-year-old Persian cat was examined for constipation, anorexia, and vomiting that was subsequently found to be due to a pseudomycetoma originating from the descending colon and sublumbar region, and causing mechanical obstruction of the colon and rectum. Multiple discrete hyperechoic foci likely representing fungal grains within the lesion gave the mass a coarse echotexture on ultrasound and was supportive of the diagnosis and computed tomography allowed delineation the extent of the mass. A pseudomycetoma is a granulomatous/pyogranulomatous reaction that surrounds dermatophytic fungal hyphae. Definitive diagnosis of a dermatophytic pseudomycetoma requires identification of the etiologic agent by cultivation or immunohistochemical staining. A pseudomycetoma should be included in the differential diagnosis for an abdominal mass in a Persian cat, especially is accompanied by the sonographic findings noted above.

Eumycetoma caused by Cladophialophora bantiana in a dog.

We report a case of eumycetoma due to Cladophialophora bantiana in a 3-year-old male Siberian Husky living in France. The dog presented a tumefaction on the thorax and deformity of the second and third subjacent ribs, which were surgically removed. Macroscopic black granules were visible on the ribs, and direct microscopic examination revealed their fungal origin. Cultures yielded pure colonies of C. bantiana. The identification of the causative agent was confirmed after amplification and sequence analysis of fungal internal transcribed spacers 1 and 2 and 5.8S ribosomal DNA regions. Surgery and antifungal treatment with oral itraconazole associated with flucytosine allowed apparent cure after a 10-month follow-up. Envenomation with pine processionary caterpillars (Thaumetopoea pityocampa) and subsequently intensive corticotherapy were considered as possible predisposing factors. This is, to the best of our knowledge, the first case in which C. bantiana is identified as the causative agent of eumycetoma.

Invasive pulmonary pseudallesheriosis in a cross-breed calf.

Pulmonary pseudallescheriosis was diagnosed in a two-months old calf. Pneumonic lungs with yellow-white nodules on the surfaces revealed granulomatous lesions microscopically. Septate, pleomorphic hyphae were present in the central caseated core with a bright eosinophilic periphery surrounded by polymorphonuclear cells and macrophages followed by a zone of epithelioid cells admixed with lymphocytes and plasma cells. The fungal agent was demonstrated by Grocott's silver methenamine staining. On isolation, morphologically it was found to be indistinguishable from that of Pseudallescheria boydii. It appears to be first report of fatal mycotic pneumonia in a calf due to P. boydii. The emphasis is given for further detailed investigation on this aspect in veterinary mycopathology.

Eumycetoma caused by Curvularia lunata in a dog.

Curvularia lunata was cultured from black granules found in granulomatous tumefactions excised from the subcutis of a three year old Medium Schnauzer dog. Draining sinuses were present in some of the tumefactions. Accordingly the diagnosis of eumycotic mycetoma was made. This diagnosis was confirmed by histopathological examination. During the four years following the first surgical intervention, several more similar tumefactions were excised on three different occasions. The dog died of chronic renal failure at the age of 8 years. There was no bone involvement or visceral diffusion of the fungus. The granules were examined by scanning electron microscopy. Immunoglobulins in the dog's serum, assessed by a qualitative test, proved to be equal to immunoglobulins in the serum of a control dog. Precipitating antibodies against C. lunata were not found. The dog was treated for 150 days with itraconazole. In spite of good initial results, recurrence of the fungal lesions were observed after the treatment's interruption. Further treatment with itraconazole for 45 days proved ineffective. No side effects of the drug were observed. This is, to the best of our knowledge, the first case in which C. lunata is identified as the causative agent of an animal eumycetoma.

Black grain eumycetoma (Madurella mycetomatis) in the abdominal cavity of a dog.

A uterine stump granuloma was surgically removed from a sterilized bitch. Histopathology and fungal culture revealed Madurella mycetomatis eumycetoma. Infection may have occurred through a cesarean wound dehiscence. Long-term fluconazole therapy was instituted but failed to arrest and eliminate the infection.

Reproducción experimental del micetoma en ratón por nocardia brasiliensis / Experimental reproduction of mycetoma by nocardia brasiliensis in mouse

Se presenta la reproducción experimental del micetoma podal e intraperitoneal en el ratón albino Swiss por nocardia brasiliensis. Las inoculaciones en almohadilla plantar y por vía intraperitoneal se realizaron usando tres tipos de adjuvantes: solución fisiológica estéril, glicerina+polvo de piedra pómez y mucina gástrica al 5%. La reproducción de gránulos actinomicóticos se obtuvo en el 100% de los animales. La producción de edema, tumefacción, gránulos y la respuesta celular del huésped demuestran que es posible la reproducción experimental de micetomas por nocardia brasiliensis y que el ratón albino swiss es suceptible a este microorganismo.

Eumycotic mycetoma caused by Pseudallescheria boydii in a dog.

Abdominal eumycotic mycetoma caused by Pseudallescheria boydii was diagnosed in a 3-year-old male Siberian Husky. The dog was examined because of weight loss and signs of depression. Initially, pyrexia was the only clinical finding. Antibiotic and corticosteroid treatment was ineffective. Two weeks later, the dog's appetite had decreased, it had vomited a few times, and the caudal portion of the abdomen was sensitive to palpation. Hematologic and serum biochemical abnormalities consisted of anemia, leukocytosis, hypoglycemia, hypoalbuminemia, hyperglobulinemia, and high alkaline phosphatase activity. One week later, the dog's condition continued to worsen, and testicular swelling was observed. The dog was castrated. Microscopic examination of specimens obtained at surgery revealed pyogranulomatous periorchitis with mycetoma granules. Ketoconazole treatment was initiated and continued until the dog died one month later. Necropsy revealed multifocal duodenal ulcers, with transmural pyogranulomatous enteritis, pancreatitis, and peritonitis. This case is unique because the etiologic agent apparently entered via the intestinal tract rather than by contamination of an external wound.

Actinomycotic mycetoma in a cat.

Actinomycotic mycetoma, a chronic, progressive infection of the subcutaneous tissue characterized by tumefaction, draining sinuses, and grains, was diagnosed in the right hindlimb of a young adult, male cat. The organisms that cause actinomycetoma are soil or plant saprophytes that gain entrance to the skin through abrasion or traumatic implantation. Streptomyces griseus, an organism generally considered to be a saprophyte, was cultured bacteriologically. Despite extensive surgery and long-term antibiotic therapy, the infection persisted, and the cat was euthanatized.

Mycetoma in a grand Eclectus (Eclectus roratus roratus) parrot.

A Grand Eclectus parrot with central nervous system disturbances and wing paralysis was necropsied. There were two grayish-black nodules in the upper left thoracic cavity and one nodule in the lower left lung. In addition, several nodules were present in the cerebral hemispheres and optic lobes. The cerebellum had extensive areas of granulomatous lesions. Microscopically, brown-staining hyphae were observed in the nodules. Curvularia geniculata was isolated from the lesions. A diagnosis of mycetoma was based on histologic lesions and isolation of fungus from the lesions.

Mycetoma-like granuloma in a cat caused by Microsporum canis.

A solitary subcutaneous nodule from a Persian cat consisted of coalescing mycetoma-like granulomas containing abnormal hyphae of Microsporum canis. Overlying hair follicles were heavily laden with dermatophytes but had little associated perifollicular inflammation. The complex classification of dermatophyte-induced dermal inflammatory lesions is reviewed.