Disseminated intestinal basidiobolomycosis with mycotic aneurysm mimicking obstructing colon cancer

Abstract

Basidiobolomycosis is a rare fungal infection that may affect the gastrointestinal tract. It is caused by Basidiobolus ranarum and less than 80 cases have been reported in the literature. The incidence seems to be higher in the Middle East and in particular Saudi Arabia where most cases are diagnosed in the south-western region. An 18-year-old woman presented to the emergency department with an obstructing caecal mass initially suspected to be malignant. Surgical resection was complicated by bowel perforation, histology and cultures confirmed basidiobolomycosis infection. The postoperative course was complicated by an enterocutaneous fistula, fungal intra-abdominal abscesses, liver and lung abscesses, formation of mycotic hepatic artery aneurysm and meningoencephalitis. The patient eventually expired due to sepsis despite aggressive treatment. Diagnosis and management of such rare cases are very challenging and require a multidisciplinary approach. Complications are common and associated with a high mortality.

Keywords: gastrointestinal surgery; gastrointestinal system; general surgery; infections; liver disease.

Figure 1

Coronal enhanced CT of the abdomen showing an obstructing caecal mass (arrow).

Figure 2

Right hemicolectomy specimen showing caecal wall thickening with necrotic debris in the lumen.

Figure 3

(A) Axial and (B) coronal enhanced CT of the abdomen: multiple scattered hepatic abscesses, largest seen anterior to the caudate lobe extending downward just above the pancreatic head (arrow).

Figure 4

Caecal mass, transverse and longitudinal sections of broad fungal hyphae (periodic acid-Schiff fungal stain, ×200 original magnification).

Figure 5

Caecal mass, transverse and longitudinal sections of fungal hyphae showing sunburst pattern of Splendore-Hoeppli phenomenon and numerous eosinophils (H&E, ×400 original magnification).

Figure 6

Liver biopsy, pauciseptate fungal hyphae with foreign body type multinucleate giant cells (periodic acid-Schiff fungal stain, ×200 original magnification).

Figure 7

Axial enhanced CT scan showing increase of the right iliac fossa collection measuring 8.4×8.2 cm.

Figure 8

(A) Axial and (B) coronal enhanced CT shows development of common hepatic artery aneurysm (yellow arrow), surrounded by the previously seen abscess anterior to the caudate lobe extending downwards towards the head of pancreas (orange arrow).