Colonic Basidiobolomycosis-An Unusual Presentation of Eosinophilic Intestinal Inflammation

Abstract

Basidiobolomycosis is a rare fungal disease caused by Basidiobolus ranarum. Involvement of the gastrointestinal tract is unusual and poses both a diagnostic and therapeutic challenge, as clinical signs are non-specific and predisposing risk factors are lacking. It can mimick inflammatory bowel disease, primary immunodeficiency, or a malignancy and should be considered in patients who do not respond to standard therapy. We present the case of a 22 months old boy with confirmed colonic Basidiobolomycosis, who presented with severe eosinophilic inflammation of the gastrointestinal tract. Panfungal PCR performed on DNA extracted directly from a tissue sample confirmed the presence of Basidiobolus. He made a full recovery with a combination of surgery and prolonged targeted antifungal medication.

Keywords: basidiobolomycosis; children; colon; eosinophilic inflammation; intestine.

Figure 1

Timeline.

Figure 2

Abdominal ultrasound. Marked thickening of colon loops within mid epigastric and left upper quadrant representing transverse (see blue arrows) and descending colon.

Figure 3

Abdominal CT with contrast. Marked bowel wall thickening of left colon (see blue arrows) extending from the distal transverse to the descending colon. There is an area of spared bowel in the mid descending colon. The thickened bowel is homogenous in attenuation, with relative hyper enhancement of the mucosa. There is abrupt transition between normal and abnormal bowel (shouldering). There is involvement of the serosa with multiple serosal nodules and infiltration of the pericolonic fat.

Figure 4

Same as Figure 3.

Figure 5

HE stain of bowel biopsy. Cores of fibrous tissue with extensive necrotizing granulomatous inflammation with many foreign body type multinucleated giant cells (see red arrow) and large numbers of eosinophils.

Figure 6

Resected left hemicolon.

Figure 7

HE stain of the excised bowel. Splendore Hoeppli (see red arrow).

Figure 8

Grocott stain of the excised bowel. Basidiobolus hyphae (see red arrow). Typically thin-walled, septated hyphae, haphazardly branching, surrounded by eosinophilic material.