A case of Exophiala dermatitidis-induced phaeohyphomycosis in a cat with multiple intra-abdominal masses.

Pus discharge containing black granular materials (1-2 mm in diameter) was found in the abdominal skin of a 13-year-old sterilized female cat. Abdominal ultrasonography revealed a large intra-abdominal mass with abundant blood flow beneath the skin lesion. Laparotomy revealed a large mass that adhered to the spleen and left kidney. Similar small lesions were found in the abdominal wall and mesentery. The masses were surgically removed along with the spleen and kidney. Histopathologically, the mass lesions consisted of granulomas with lesional pigmented fungi, and the cat was diagnosed with phaeohyphomycosis. Uisng genetic analysis, the Exophiala dermatitidis was identified as the causative pathogen.

Disseminated phaeohyphomycosis due to Cladophialophora bantiana in an immunocompetent child.

A 3-year-old boy presented with acute headache, vomiting and right focal clonic seizures without history of fever, joint pain or altered sensorium. Neuroimaging showed multifocal contrast enhancing lesions with significant perilesional edema. CECT chest and abdomen showed multiple variable sized nodules in the lungs and hypodense lesion in liver with mesenteric lymphadenopathy. There was persistent eosinophilia with maximum upto 35 %. Liver biopsy and brain biopsy revealed Cladophialophora bantiana. He was treated with IV liposomal amphotericin and voriconazole for 6 weeks with repeat neuroimaging showing more than 50 % resolution of the intracranial lesions. He was transitioned to oral combination of flucytosine and voriconazole. At 14 months follow-up, he remained symptom free with complete radiological resolution of the lesions and no eosinophilia. High suspicion, an aggressive approach in obtaining microbiological diagnosis and timely combination antifungal therapy may give satisfactory outcome without surgery.

Cytology of Rhytidhysteron rufulum: An emerging cause of phaeohyphomycosis.

Fine-needle aspiration cytology (FNAC) is often the first-line investigation for detection of any fungal infection. Rhytidhysteron rufulum is an emerging dematiaceous fungus detected as a human pathogen. FNAC combined with molecular techniques helps in the detection of rare fungal species, especially in cases of non-sporulating fungi. We describe the cytomorphologic features of this species in a 62-year immunocompetent male who presented with a localised subcutaneous infection. Molecular studies helped in the final diagnosis.

Combination therapy with itraconazole and terbinafine for phaeohyphomycosis caused by Exophiala spinifera: A case report and literature review.

Exophiala spinifera is a rare dematiaceous fungus causing cutaneous, subcutaneous and disseminated phaeohyphomycosis (PHM). Standard antifungal therapy for PHM is still uncertain. Here, we report a case of a Chinese male with PHM caused by E. spinifera, who received significant clinical improvement after the treatment with oral itraconazole and terbinafine. With the aim of evaluating the antifungal therapy for PHM caused by E. spinifera, a detailed review was performed.

Pulmonary abscess caused by Cladosporium cladosporioides after receiving outpatient chemotherapy.

Cladosporium cladosporioides is one of the most ubiquitous dematiaceous fungi that seldomly occur human infection. Here, we demonstrate a rare case of pulmonary phaeohyphomycosis with a distinctive pulmonary lesion during the nadir period of outpatient chemotherapy against endometrial cancer. In addition to severe neutropenia, excessive exposure to C. cladosporioides at patient's residence was considered as dominant causative factor. More caution is considered necessary for pulmonary phaeohyphomycosis in patients who receive outpatient chemotherapy and are homebound during neutropenic status.

Subcutaneous phaeohyphomycosis caused by Alternaria section Alternaria.

A woman presented with purulent infiltrating plaques on her hands and arms after a 7-year history of nephrotic syndrome. She was ultimately diagnosed with subcutaneous phaeohyphomycosis, which is caused by Alternaria section Alternaria. The lesions completely resolved after 2 months of antifungal treatment. Interestingly, spores (round-shaped cells) and hyphae were observed in the biopsy and pus specimens, respectively. This case report highlights that distinguishing subcutaneous phaeohyphomycosis from chromoblastomycosis may be difficult if the diagnosis is solely based on pathological findings. It also emphasizes that the parasitic forms of the dematiaceous fungi in immunosuppressed hosts may vary with the site and environment.

Clinical characteristics of central nervous system phaeohyphomycosis: A brief report of 20 years' experience.

Central nervous system (CNS) phaeohyphomycosis is a rare and often fatal fungal infection. Our study reported a case series of eight CNS phaeohyphomycosis cases at our institution over the past 20 years. We did not observe the common pattern of risk factors, abscess location, or number of abscesses among them. Most patients were immunocompetent without classic risk factors for fungal infection. Early diagnosis and aggressive management with surgical intervention and prolonged antifungal therapy can lead to a favorable outcome. The study highlights the need for further research to better understand the pathogenesis and optimal management of this challenging rare infection.

Mouse Models of Phaeohyphomycosis.

Infections by dematiaceous fungi especially phaeohyphomycosis are an emerging group of infectious diseases worldwide with a variety of clinical presentations. The mouse model is a useful tool for studying phaeohyphomycosis, which can mimic dematiaceous fungal infections in humans. Our laboratory has successfully constructed a mouse model of subcutaneous phaeohyphomycosis and found significant phenotypic differences between Card9 knockout and wild-type mice, mirroring the increased susceptibility to this infection observed in CARD9-deficient humans. Here we describe construction of the mouse model of subcutaneous phaeohyphomycosis and related experiments. We hope that this chapter can be beneficial for the study of phaeohyphomycosis and facilitate the development of new diagnostic and therapeutic approaches.

Phaeohyphomycosis: A study from tertiary health care center in North India.

Objectives: Phaeohyphomycosis refers to infections caused by phaeoid/dematiaceous or darkly pigmented fungi. This study was undertaken to further increase our knowledge about the incidence of phaeohyphomycosis and its causative agents. Materials and Methods: The present study was conducted over a period of one and a half years (January 2018-June 2019) on specimens received from patients with varied clinical manifestations ranging from superficial infections, subcutaneous cysts, pneumonia, brain abscess to a disseminated infection. These specimens were processed in the Department of Microbiology for potassium hydroxide (KOH) examination and culture and in Pathology for cytology/histopathological examination (HPE). All specimens positive on direct examination for dark grey, brown or black fungi were included in the study. Results: A total of 20 specimens were confirmed as phaeohyphomycosis. Most of the patients belonged to the age group of 41 to 50 years. Male: Female ratio was 2.3:1. Trauma was the most common risk factor. Spectra of the isolated fungal pathogens comprised of Bipolaris species, Exophiala species, Curvularia geniculata, Phialemonium species, Daldinia eschscholtzii, Hypoxylon anthochroum, Phaeoacremonium species, Leptosphaerulina australis, Medicopsis romeroi, Lasiodiplodia theobromae, Eutypella species, Chaetomium globosum, Alternaria species, Cladophialophora bantiana and 2 unidentified dematiaceous fungi. Recovery from phaeohyphomycosis was seen in 12 patients, 7 were lost to follow up and one patient succumbed to the illness. Conclusion: Infections caused by phaeoid fungi can no longer be viewed as rare. In fact, phaeohyphomycosis can have myriad of presentations spanning from mild cutaneous infections to fatal brain disease. Therefore, a high index of clinical suspicion is needed to diagnose such infections. The primary treatment modality remains surgical removal of the lesion in cutaneous or subcutaneous infections however disseminated disease with a guarded prognosis requires aggressive management.

Pulmonary phaeohyphomycosis due to Exophiala dermatitidis in a patient with pulmonary non-tuberculous mycobacterial infection.

A 65-year-old Japanese woman repeatedly withdrew and resumed antibiotics against pulmonary non-tuberculous mycobacterial infection caused by Mycobacterium intracellulare for more than 10 years. Although she continued to take medications, her respiratory symptoms and chest computed tomography indicated an enlarged infiltrative shadow in the lingular segment of the left lung that gradually worsened over the course of a year or more. Bronchoscopy was performed and mycobacterial culture of the bronchial lavage fluid was negative, whereas Exophiala dermatitidis was detected. After administration of oral voriconazole was initiated, the productive cough and infiltrative shadow resolved. There are no characteristic physical or imaging findings of E. dermatitidis, and it often mimics other chronic respiratory infections. Thus, when confronting refractory non-tuberculous mycobacterial cases, it might be better to assume other pathogenic microorganisms, including E. dermatitidis, and actively perform bronchoscopy.

A rare case of refractory facial phaeohyphomycosis caused by Cladosporium halotolerans successfully treated with aminolevulinic acid photodynamic therapy.

A 55-year-old female presented with a gradually enlarged red plaque and ulceration on the right side of her nose, face and suborbital region for ten years. The histopathologic features indicated infectious granuloma. The results of the fungal culture of the tissue and DNA sequencing identified as Cladosporium halotolerans infection. The patient was diagnosed with phaeohyphomycosis due to Cladosporium halotolerans. In this case, it was unsuitable for surgical treatment since the lesion was located periorbital. Furthermore, the patient had a poor response to oral itraconazole (400 mg/d) for 9 months. Therefore, ALA-PDT was added to the treatment regimen. The patient received ALA-PDT irradiation 5 times at 2-week intervals and achieved significant clinical remission. We believe that ALA-PDT may be an effective and safe adjuvant therapy.

Not all black fungus is mucormycosis: A challenging case of Medicopsis romeroi.

In this case of phaeohyphomycosis, fine needle aspiration cytology enabled a rapid diagnosis and prompt treatment. This infection is quite prevalent in immunocompromised individuals; however, the Medicopsis romeroi species is a rare causative agent. These cases are associated with inadequate response to standard antifungal therapy and require discussion.

Cutaneous phaeohyphomycosis in a greater bulldog bat (Noctilio leporinus) in northeastern Brazil.

An adult male greater bulldog bat (Noctilio leporinus) was found dead in a suburban area in the municipality of Patos, Paraiba, northeastern Brazil. At post-mortem examination, the bat was emaciated and had multifocal to coalescent grey, crusted, dry, scaly cutaneous lesions, irregularly distributed over the dorsal thoracoabdominal region, muzzle, labial commissures, ears and dorsoventral surfaces of the patagia. Histopathology revealed numerous longitudinal and transverse sections of fungal organisms, with weakly basophilic walls, associated with multifocal areas of ulceration of the epidermis, necrosis, rupture and discontinuity of collagen fibres in the dermis without any inflammatory response. Molecular identification matched the organism to Cladosporium spp, Curvularia spp, Exserohilum spp, Bipolaris spp (100%) and Alternaria spp (97%), all of which have been associated with phaeohyphomycosis. Phaeohyphomycosis should be included as a differential diagnosis of cutaneous lesions in chiropterans.