Venous intestinal ischemia of fungal origin as a cause of intestinal obstruction in immunocompromised patients: case report and literature review.

Background: Mucormycosis is a highly lethal opportunistic fungal disease caused by ubiquitous molds of the order Mucorales, with Rhizopus, Lichtheimia and Mucor being the most common genera. This rare disease primarily affects immunocompromised patients, with presentations ranging from rhino-orbito-cerebral infections to disseminated mucormycosis with angioinvasion, leading to thrombosis and tissue infarction. Gastrointestinal mucormycosis is the least common clinical presentation and is believed to be secondary to spore ingestion. It can involve multiple components of the gastrointestinal tract, such as the stomach, liver, ileum, and colon, with nonspecific manifestations, including pain, nausea, vomiting, and abdominal distension. The initial clinical presentation may even manifest as gastrointestinal bleeding due to gastric ulceration or intestinal perforation.

Case presentation: Here we present the case of a 48-year-old male patient with a 9-year history of human immunodeficiency virus (HIV) infection who was hospitalized in the context of febrile neutropenia and whose acute respiratory infection was documented; therefore, antibiotic treatment was initiated. However, due to persistent febrile peaks and peripheral blood showing documentation of multilineage cytopenias, a bone marrow biopsy was performed, compatible with presenting features of marrow myelodysplasia. During hospitalization, the patient presented left flank abdominal pain, and an abdominal computed tomography (CT) scan revealed signs of intussusception of a small bowel loop at the distal jejunum level, leading to intestinal obstruction with ischemic progression, requiring ileectomy (60 cm). Histopathological analysis of the resected intestine revealed severe transmural ischemic changes associated with venous thrombosis due to fungal structures, with histochemical studies demonstrating the presence of zygomycete (Mucor) fungal structures, leading to the initiation of treatment with amphotericin B. However, despite treatment, the patient experienced progressive clinical deterioration with persistent fever and ventilatory failure, with follow-up tests showing absolute neutropenia and blood cultures positive for yeast, leading to death 52 days after admission.

Conclusions: The diagnosis of intestinal mucormycosis may be delayed due to the lack of specificity of the signs and symptoms. Pathologists as well as histopathological studies are essential for timely treatment.