Gastrointestinal Basidiobolomycosis: An Unusual Fungal Infection Mimicking Colon Cancer

Abstract

Context.—Basidiobolomycosis is a rare disease caused by the fungus Basidiobolus ranarum, an environmental saprophyte found worldwide. Patients with B ranarum infection may present with subcutaneous, gastrointestinal, or systemic lesions. Gastrointestinal basidiobolomycosis poses diagnostic difficulties, as its clinical presentation is nonspecific, with no identifiable risk factors. Objective.—To discuss and compare the clinical features and histopathologic findings and other ancillary techniques that could be helpful in identifying gastrointestinal basidiobolomycosis. Design.—We report 3 cases of gastrointestinal basidiobolomycosis and describe the clinical and morphologic findings while emphasizing the importance of identifying this unusual entity on endoscopic biopsies, thus avoiding unnecessary major surgeries. Fungal cultures were also performed, which are of diagnostic significance. Our first patient was lost to follow-up; however, patients 2 and 3 were followed up for 4 and 2 years, respectively. Results.—In all 3 cases, patients presented with a clinical profile suggestive of malignancy. None of the patients gave any specific history. There was widespread abdominal disease with peritoneal involvement and colonic masses. Colonoscopic biopsy specimens showed nonspecific inflammation in 1 case; however, they showed only granulomatous inflammation in a second case and granulomas associated with fungal hyphae in a third. Typical morphology included hyphae, irregularly branched, thin-walled, occasionally septated and surrounded by a thick eosinophilic cuff (Splendore-Hoeppli phenomenon). Conclusion.—Gastrointestinal basidiobolomycosis can be detected on small endoscopic biopsy. The unequivocal diagnosis requires microbiologic cultivation of the fungus obtained from tissues. The prognosis for this disease is usually favorable as seen in 3 of our cases; however, cases with fatal outcome are on record.

Basidiobolomicosis subcutáneo, reporte de caso

“…La basidiobolomicosis se presenta en África, India, el Lejano Oriente, América Latina y el sur de los Estados Unidos de América (Habib et al, 2020). Una revisión de la zigomicosis por B ranarum sugiere que se sabe que este moho produce varias enzimas, por ejemplo, lipasa y proteasa, que probablemente desempeñan un papel en la patogenia de las infecciones (Nemenqani et al, 2009). Su manifestación clínica inicia con engrosamiento progresivo difuso del tejido subcutáneo y deformación significativa debido a la inflamación granulomatosa crónica del tejido subcutáneo; las lesiones clínicas a veces se confunden con malignidad (Rermluk et al, 2017).…”

Primary Basidiobolomycosis of the Cecum in Immunocompetent Patients: Two Case Reports

“…Culture on Sabouraud agar at 20 -30 °C with incubation for 2 -3 days is the gold standard for definitive diagnosis. The fungal growth appears as white to pale grey, waxy, or glabrous colonies with radial folds covered by aerial hyphae [20]. However, in most reported cases, the patients have undergone surgical resection with the clinical impression of mass and therefore the specimens have been transferred to the laboratories in formalin and no cultures have been performed.…”

“…Both Conidiobolus (mean of the hyphal diameter, 8 µm; ranging in diameter from 5.0 up to 13 µm) and Basidiobolus species are usually encountered in the materials of the decaying fruit or vegetable and the soil [10]. They are separated from B. ranarum by the fact that these fungi affect the head and neck region in immunocompromised patients [20]. Visceral involvement by these fungi has not been reported [10,24].…”

Histologic features of colonic infections

“…The organisms have broad, occasionally septate hyphae with an appearance resembling crinkled cellophane [27]. The organisms are typically surrounded by a striking Splendore-Hoeppli reaction, which occurs less frequently with Mucor ( [28,29];…”