Gastrointestinal involvement of unusual Mucormycete Syncephalastrum racemosum in a diabetic patient with adenocarcinoma: rare case presentation with review of literature

Background: Mucormycosis is a serious and often fatal mycotic infection caused by members of class Mucormycetes in populations with immunologic or metabolic disorders. Though several clinical manifestations are associated with mucormycetes, gastrointestinal involvement is quite rare.

Case description: We described a rare case of invasive fungal infection due to Syncephalastrum racemosum associated with gastric adenocarcinoma in a 48-year-old male patient with type II Diabetes mellitus. He presented with complaints of abdominal pain, nausea, vomiting, dyspepsia, dysphagia, loss of appetite, and weight. Histopathological examination showed broad and aseptate hyphae and culture of endoscopic biopsy tissue from pylorus and antrum yielded the fungal pathogen S. racemosum. The species was confirmed by molecular sequencing of D1/D2 region of the ribosomal DNA. The in vitro susceptibility of S. racemosum was tested by broth microdilution assay as per CLSI guidelines. The MICs suggest that the isolate was susceptible to Amphotericin B (0.25 µg/ml), Itraconazole (0.25 µg/ml) and Posaconazole (0.06 µg/ml) and showed resistance to Micafungin (>16 µg/ml). The patient was successfully treated with radical subtotal gastrectomy with lymphadenectomy and Amphotericin B antifungal therapy. There was a dilemma in concluding the pathogenicity of the isolate since; the symptoms noted were common for both gastric adenocarcinoma and mucormycosis. A review of previously reported cases on Syncephalastrum was presented in the paper with their clinical manifestations, treatment, and outcome.

Conclusion: To the best of our knowledge, this is the first report from India on the gastrointestinal involvement of S. racemosum. Patients with immunocompromised status are more prone to mucormycotic infections, and any typical presentations should be carefully examined for their etiological agent, and appropriate species directed therapy would help in a better outcome.

Keywords: Adenocarcinoma; Diabetes mellitus; Mucormycosis; Syncephalastrum racemosum.