Colorectal schistosomiasis: clinicopathologic study and management

Large bowel obstruction secondary to schistosomiasis-related colonic stricture

•

Schistosomiasis can manifest as non-obstructive polypoid lesions due to deposition of schistosomal eggs.

•

Obstructive lesions, such as fibrotic strictures, secondary to the infectious sequelae of schistosomiasis are rare.

•

Although schistosomiasis can be diagnosed on imaging and laboratory tests, there is no conclusive method of ruling out a malignancy.

•

Praziquantel is a safe and effective treatment for schistosomiasis, and prevents future sequela of the parasitic infection.

•

Surgical resection provides definitive treatment resulting in symptom resolution while ruling out a neoplastic etiology.

Introduction

Intestinal involvement of schistosomiasis uncommonly involves the formation of non-obstructive polypoid lesions; however, obstructing fibrotic stenoses and strictures secondary to chronic infection are extremely rare with only nine reported cases in the literature.

Presentation of case

An 85-year-old Southeast Asian female originating from the Philippines presents with a one-day history of obstructive symptoms in the setting of chronic constipation over the past four months. Subsequent CT imaging and colonoscopy biopsy revealed a nodular cecal mural wall thickening with chronic inflammation and a single Schistosoma egg. Despite treatment with praziquantel, and medical optimization the patient did not improve. Additionally, a malignancy as the underlying cause of obstruction could not be ruled out as such, she had a right hemicolectomy. Final pathology confirmed the diagnosis of intestinal submucosal schistosomiasis causing fibrotic stenosis.

Conclusion

Obstructing lesions including fibrotic stenoses secondary to Schistosomiasis infection can be managed safely with medical co-morbidity optimization when possible, treatment with Praziquantel and surgical resection of the involved area of colon. Given the risk of malignancy and the inability to clinically distinguish between infectious and neoplastic processes, surgical management is recommended.

Huge bilharzial polyp mimicking colon cancer

Bilharziasis (Schistosomiasis) is the third devastating tropical disease globally and is endemic in many countries including Egypt. The pathology of chronic colonic schistosomiasis results from egg-induced immune response, granuloma formation, and associated fibrotic changes that may manifest as bloody diarrhea, cramping, and, eventually, inflammatory colonic polyposis. Huge polyps complicating schistosomiasis are not frequently reported in the literature. Also, huge polyps as a sole manifestation of intestinal bilharziasis are rather rarely reported. Here, we report an Egyptian male patient who presented with bleeding per rectum with a huge polyp on colonoscopy, with morphological traits that mimicked colon cancer and proved to be of bilharzial etiology after surgical excision.

The patient presenting with acute dysentery--a systematic review

OBJECTIVES

The etiologies, clinical presentations and diagnosis of acute pathogen-specific dysentery in children and adults in industrialized and developing regions is described to help develop recommendations for therapy.

METHODS

We conducted a systematic review of literature published between January 2000 and June 2011 to determine the frequency of occurrence of pathogen-specific dysentery.

RESULTS

Shigella, Salmonella, and Campylobacter remain the most frequent bacterial causes of dysentery worldwide. Shiga toxin-producing Escherichia coli (STEC) is potentially important in industrialized countries. Entamoeba histolytica must be considered in the developing world, particularly in rural or periurban areas. Clinicians should use epidemiological clues and knowledge of endemicity to suspect Vibrio spp., Aeromonas spp., Plesiomonas spp., Yersinia enterocolitica, Clostridium difficile, Cytomegalovirus or Schistosoma mansoni in cases presenting with dysentery. A single fecal sample studied for etiologic agents is the customary way to make an etiologic diagnosis.

CONCLUSIONS

While a majority of dysenteric cases will not have an identifiable agent causing the illness, when an etiologic organism is identified, other than STEC, each has a specific recommended form of therapy, which is provided in this review.

The value of colonoscopy in schistosomal, tuberculous, and amebic colitis. Two-year experience

Forty-six patients were diagnosed as having schistosomal, tuberculous, or amebic colitis over a two-year period using colonoscopy and biopsy. Both schistosomal and tuberculous colitis could be diagnosed by characteristic endoscopic and histologic features in the majority of cases. Colonoscopy provided the added advantage of endoscopic polypectomy at the diagnostic session itself. The yield of granulomas in tuberculous lesions was 100 percent, although acid-fast bacilli could not be recovered from any. The endoscopic picture of amebic colitis often resembles that of inflammatory bowel disease; hence endoscopic biopsies are of paramount importance in establishing a correct diagnosis, especially in developing countries where both diseases exist with considerable frequency.

Rectocolonic calcification due to schistosomiasis. A clinicoradiologic study

Four patients who had intravenous pyelography were found to have radiologically visible calcification of the rectocolon and urinary tract due to schistosomiasis. All four patients had mild proctocolitis colonoscopically and multiple calcified schistosomal ova were found in the submucosa histologically. The authors believe that radiologically visible rectocolonic calcification is more common than reported and that it is associated with a clinically mild or latent form of schistosomiasis.

Colorectal schistosomiasis. Endoscopic polypectomy

The role of colonoscopic polypectomy for schistosomal polyps was studied. The results showed that, in spite of the large number of polyps, a total of 404 polyps were removed from 20 patients. The procedure is feasible with minimal complications. A marked reduction of rectal bleeding occurred in half the patients, and the remaining half had minimal symptoms. Colonoscopic polypectomy gives equal results to colonic excision for schistosomal polyps.