Gastrointestinal Basidiobolomycosis in pediatric patients: A diagnostic dilemma and management challenge

Abstract

Introduction: Basidiobolomycosis is a rare fungal disease, lately appearing in the gastrointestinal system of pediatric patients. Their clinical presentation resembles that of lymphoma or granulomatous inflammations. This non-specific presentation makes Gastrointestinal Basidiobolomycosis (GIB) a diagnostic challenge.

Methods: We are reporting the largest series of pediatric GIB, from Saudi Arabia. 12 patients were diagnosed between January 2012 and December 2019, between the ages of 16 months and 8 years.

Results: The most common symptoms were fever and abdominal pain. Further examination revealed an abdominal mass. Biopsy of the mass was the mainstay of diagnosis, with histological findings of typical filamentous fungal hyphae and zygospores, surrounded by eosinophils.

Conclusion: Role of surgery was limited to establishing the diagnosis and dealing with complications. Antifungal medication was the cornerstone of treatment in all our patients. Three of our patients were exceptional with complications such as entero-cutaneal fistula, entero-enteric fistula and short bowel syndrome. These complications have not been previously reported. We have discussed the challenges related to their management.The diagnosis of GIB in pediatric patients with abdominal mass, needs a high index of suspicion. We believe outcome depends on the severity of disease, involvement of surrounding tissues and presence of complications at the time of diagnosis.

Keywords: Abdominal mass; Basidiobolomycosis; Entero-cutaneal fistula; Entero-enteric fistula; Fungal hyphae; Fungal infection.

Fig. 1

Patient 2 – Selected coronal and axial images from the contrast enhanced CT scan of the abdomen. (a) The image demonstrates the huge mesenteric mass (black arrow) encasing mesenteric vessels with retroperitoneal extension involving the duodenum wall. Also noted the thickening of the transverse colon and hepatic flexure walls (short white arrows). (b) The coronal image shows the extension of the intra-abdominal mass with the portal vein thrombosis (short white arrow). Also identified the thickening of the terminal ileum (arrow head) and the dilated small bowel loops (thin white arrows).

Fig. 2

Patient 2 – Selected images from upper (a) and lower (b) GI contrast studies show the abnormally short remaining small bowel. The arrow is at the cecum.

Fig. 3

Patient 2 – The last CT scan of the abdomen with oral and IV contrast. Coronal and axial images demonstrate the small residual mass (black arrow). Also noted the persistent thrombosis of the portal vein with consequences of the venous collaterals at the porta hepatis and the splenomegaly (white arrow).

Fig. 4

Patient 8 – CT scan of the chest and abdomen with IV and oral contrast. (a) Selected coronal image demonstrates the large heterogeneous hypo dense pelvic mass (black arrow) with infiltration of the distal ileum. Fungating mass and the aneurysmal dilatation (long white arrow). (b) Axial image shows the pelvic mass and the bowel involvement (short white arrows).

Fig. 5

Patient 12 - The first CT scan of the abdomen with IV and oral contrast. (a) Selected axial image demonstrates the large right hypochondrium necrotic mass (short black arrow) involving the ascending colon causing aneurysmal dilatation of the bowel lumen (short white arrow). There is fistulous communication between the lumen and the necrotic center of the mass (long black arrow). (b) Selected coronal image demonstrates the large necrotic mass infiltrating the head of the pancreas (outlined arrow head).

Fig. 6

Case 12 - Follow up CT scan of the abdomen with IV and oral contrast administration. (a) The axial image demonstrates the necrotic right abdominal mass (black arrow) with retroperitoneal extension. The oral contrast is already in the right side of the colon (outlined arrow head) with massive intraperitoneal free fluid. (b) Coronal image demonstrates the duodeno-colic fistula (short white arrow) and the colocutaneous fistula (long white arrow).

Fig. 7

Upper GI water soluble contrast study shows the contrast flowing from the duodenum into the right colon through a fistulous tract (arrow).

Fig. 8

Patient 12 – Follow-up CT scan of the abdomen 7 months after the start of treatment (a) Coronal planes show marked reduction of the lower abdominal necrotic mass with a residual mesenteric mass (black arrow) involving the duodenum. A dilated CBD (short white arrow) and persistent dilated small bowel segments (long white arrows) are seen. (b) Axial planes show persistent colocutaneous fistula (arrow head).

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