Schistosomiasis, although unusual in North America, is a common disease worldwide. Symptoms vary depending on the species involved. Immigrants from endemic regions are the commonly affected patients found in North America. In most cases, schistosomiasis does not present with right lower quadrant pain. Even in endemic regions, this form of presentation is uncommon. In the United States, most cases of right lower quadrant pain often will be treated as appendicitis. Questions remain unanswered as to whether the schistosomes cause appendicitis or are found incidentally in these cases. Stool and urine specimens may be helpful in making a diagnosis. Most cases require operative intervention to rule out appendicitis and to obtain tissue for histopathologic diagnosis. Praziquantel is effective in eradicating infestations.

Schistosomal appendicitis. Ann Saudi Med. 1995 Jul;15(4):347-9.

This is a retrospective study involving 4708 consecutive appendix specimens removed over a period of 6.5 years for a clinical diagnosis of acute appendicitis, 64 (1.3%) of which showed histological evidence of schistosomiasis. Thirty-four schistosomal appendicitis (SA) cases were compared with 68 non-schistosomal appendicitis (NSA) cases admitted during the same period. SA patients were older in age, usually of male sex, mostly Egyptians and tended to have a higher hemoglobin and a lower leukocyte count (P<0.05). Other features were not significantly different. It is concluded that, despite these differences, there are no reliable clinical or laboratory features by which SA can be predicted preoperatively. The majority of the studied patients were either discharged before the results of the histopathology study were ready and were lost to follow-up or the reports were overlooked. Therefore, we recommend that for all post-appendectomy patients living in or coming from endemic areas of schistosomiasis, the results of the histopathology study should be processed as early as possible and before the patient can be discharged so that the treatment can be commenced. Moreover, establishing a system by which infected patients could be traced and hence treated is highly recommended.