Interesting Case Presentation by:
Dr Sadia Jama, MD
Graduate of the University of Torino Medical School, Torino/ Italy
Presently 3rd YearResidsent / Internal Medicine/ at Hannopin County Medical Center in Minneapolis, Minnesota, USA
.A case of Schistosomiasis as the etiology of acute appendicitis and review of the literature.
Case Report :
A 20 year-old Somali female who had emigrated from Africa 14 months prior, presented with acute abdominal pain, anorexia and fever to a local health care facility. On examination she had right lower quadrant tenderness and signs of peritoneal irritation such as rebound tenderness. Laboratory investigation was remarkable for elevated white cell count with neutrophilia (the patient did not have an absolute or relative eosinophilia). CT scan of her abdomen demonstrated fat stranding and edema of the appendix. The patient subsequently underwent uneventful open appendectomy. However, the histologic examination of the appendix revealed the presence of numerous mural parasitic ova, morphologically consistent with Schistosoma ova.Serologic testing confirmed active infection with Schistosomiasis. The patient was then treated with praziquantel.
Discussion
Schistosomiasis, also known as Bilharziasis after Theodore Bilharzia who is credited with describing the parasite in 1852, is a disease caused by a blood born fluke of the genus schistosoma. Like all digenetic trematodes, the intermediate hosts of the schistosomes are snails. The main forms of human Schistosomiasis are caused by five species of flatworm, known as: S. haematobium, S. mansoni, (the most prevalent in certain tropical and subtropical areas of sub-Saharan Africa, Middle East, South America and the Carebbean), and S. japonicum (most prevalent in China, Southeast Asia and some pacific rim nations). Less prevalent species are S. mekongi and S. intercaltum. In endemic areas, the infection is usually acquired in childhood. Lack of eosinophilia in this case indicates longstanding infection. In Somalia, recent data does not reflect the prevalence rates of diseases like Schistosomiasis. In some endemic areas prevalence rates can exceed 90%. Although schistosomiasis has been associated with appendicitis, especially S. hematobium, it is an unusual complication of this infection.
Conclusion
Many people immigrating from tropical areas now live in the United States. Although they live outside of their country of birth, they can still carry typical diseases of tropical areas. Schistosoiasis generally will survive for less than 10 years in the host although chronic infections have been documented exceeding 30 years. Health care providers in areas with high proportions of immigrants, refugees and migrants, should become aware of common tropical infection not traditionally encountered in the U.S.
