Protracted primary cytomegalovirus infection presenting as ileoanal pouchitis in a non-immunosuppressed patient: a case report

Abstract

Introduction: Pouchitis often occurs after proctocolectomy and ileal pouch-anal anastomosis for ulcerative colitis. It is usually deemed idiopathic and commonly responds to antibacterial therapy. To date, only a few cases of cytomegalovirus pouchitis have been documented, and only a single report describes pouchitis in a case of assumed primary cytomegalovirus infection.

Case presentation: A 26-year-old Caucasian woman underwent proctocolectomy and ileal pouch-anal anastomosis for refractory ulcerative colitis and adenocarcinoma. After 28 months she developed bloody diarrhoea, abdominal pain, fever, nausea and general malaise suggesting severe pouchitis. Antibiotic treatment reduced humoral inflammation, but failed to resolve her fever. A pouchoscopy revealed distinct pouchitis, and cytomegalovirus infection was diagnosed from pouch biopsies by polymerase chain reaction as well as conventional histology and immunohistochemistry. The infection was confirmed in her blood by polymerase chain reaction and pp65 antigen test, and was clearly defined as the 'primary' infection by serial serological tests. Intravenous treatment with ganciclovir (10mg/kg body weight/day) led to resolution of symptoms and negative cytomegalovirus deoxyribonucleic acid and pp65 within a few days. When symptoms and laboratory evidence of cytomegalovirus infection recurred a few days after completing 20 days of therapy with ganciclovir and valganciclovir, a second course of ganciclovir treatment was initiated.

Conclusions: Cytomegalovirus infection of the ileoanal pouch is an important differential diagnosis of pouchitis even in non-immunosuppressed patients and can be treated with ganciclovir.

Figure 1

Pouchoscopy findings before and after ganciclovir therapy. A and B show endoscopic photographs of the pouch one day after admission to our hospital before treatment with ganciclovir; note the size of the biopsy tweezers in the lower left corner of A. C shows a comparable view into the pouch 25 days after the end of the first hospital stay and after treatment with ganciclovir and valganciclovir. At that time point, the mucosa was smooth and shiny within the whole pouch except for a single small ulceration (about 3×7mm) in the pouch corpus; D shows the view into the pouch on day 6 of the second admission to our hospital. The ulceration, marked with an arrow, is clearly healing.

Figure 2

Microscopic findings in cytomegalovirus pouchitis. A and B show microphotographs of pouch biopsies taken before the first course of treatment with ganciclovir (hematoxylin and eosin stain, ×40). Note the enlarged nuclei of some cells and the virus-induced eosinophilic intranuclear and cytoplasmatic inclusions (arrows). C and D: immunohistochemistry revealing positive staining for cytomegalovirus (×40).