Schistosomiasis By Mohammed Mahmoud MD Lecturer of tropical

Schistosomiasis By Mohammed Mahmoud, MD Lecturer of tropical Medicine Cairo university

Specices & Distribution n S. Mansoni : Nile valley, Sudan, Brazil and Venzezuella S. Haematobium: Upper Egypt, Africa, Western Asia S. Japonicum: Far East

Life Cycle

Basic pathology n n n Cercaria Allergic dermatitis Adults No harm Eggs granulomas Fibrosis egg antigens immune complexes Katayama fever

Clinical picture n n Cercarial dermatitis: pruritic rash occurs within 24 h of cercarial penetration Katayama fever: - Usually with S. japonicum (? ? ? ) - Heavy infection with mansoni - Occur in non-immune persons - 4 -6 weeks after primary infection (time of egg deposition) - Fever, rigors, HSM, LN, ulticarial rash, marked eosionophilia

n Urogenital schistosomiasis: - S. haematobium - affect UB, ureter, genital organs - Dysuria, terminal haematuria Complications: 1 - Obstructive uropathy 2 - Cancer bladder (squamous cell)

n Intestinal schistosomiasis: - caused by mansoni - affect large bowel (rectum and sigmoid) - due to submucosal egg deposition granumona fibrosis - Clinically: 1 - Bilharzial dysentery, tensmus, mucus in stools, crampy abdominal pain 2 - Colonic polyposis Bloody diarrhea, anemia, hypoprotinemia, clubbing of fingers (never turn malig) 3 - Bilharzioma: Tender palpable mass in Lt iliac fossa Never turn malignant

Hepatic schisosomiasis n n Caused by S. Mansoni, S. Japonicum Stages: 1 - Stage of hepatomegly: ovideposition and granuloma formation liver is enlarged, smooth, firm, rounded edge. 2 - Stage of HSM (Mainly due RES) 3 - Stage of Huge splenomegly (PH) and shrunken liver (periportal fibrosis) and PS collaterals. 4 - Stage of ascites (PH and hypoprotinemia, late due to malnutrition, loss of proteins by colonic polyposis and haematemesis) 5 - Terminal hepatic failure concomitant viral hepatitis Reversal of the blood flow away from the liver (PS)

Periportal fibrosis

Paraumbilical vein

Oesophageal varices

Cardiopulmonary Schistosomiasis n n Larval Pneumonitis: allery to schistosomulae migrations low grade fever, cough, haemoptysis, wheezes, eosionophilia Core pulmonale: due to eggs of S. mansoni (reach through PS collaterals), S. haemtobium pulmonary arterioles granuloma fibrosis endertaritis oblitrans pulmonary HT RVH RVF X-ray dilatation of main pulmonary arteries (Dumble shape masses at the hilum)

Schistosomal corepulmonale

Ectopic Schistosomiasis n n Due to aberrant migration of the eggs Mainly affect brain (seizures), spinal cord (paraplegia), eye (visual field defects), skin.

Chronic salmonellosis n n n Salmonella behave atypical in cases of schistosomiasis following a rather chronic course unlike the usual acute illness Due to proliferation of salmonella in the gut of the adult schistosomes, shedding salmonella into blood chronic bacteraemia prolonged fever Ttt by antityphoid to eradicate salmonella and prevent relapse by antischistosomal therapy.

Diagnosis n n Stool and urine examination Rectal snip (gold standard) Liver biopsy Serological tests: n n Ab detection donot differentiate between active and past infection, did not decrease after ttt Ag detection indicate active infection and decrease after successful ttt

Treatment n n n Praziquantel (Drug of choice) for both mansoni and haematobium, 40 mg/kg, can be repreated 2 or 3 times in moderate and severe infections Metrifonate: for S. haematobium 10 mg/kg in 3 repeated doses at 2 weeks interval Oxamniquine: for mansoni 20 mg/kg daily for 3 days

Thank you