Schistosomiasis - Signs and Symptoms

Signs and Symptoms

Above all, schistosomiasis is a chronic disease. Many infections are subclinically symptomatic, with mild anemia and malnutrition being common in endemic areas. Acute schistosomiasis (Katayama's fever) may occur weeks after the initial infection, especially by S. mansoni and S. japonicum. Manifestations include:

• Abdominal pain
• Cough
• Diarrhea
• Eosinophilia — extremely high eosinophil granulocyte (white blood cell) count.
• Fever
• Fatigue
• Hepatosplenomegaly — the enlargement of both the liver and the spleen. Hepatic schistosomiasis is the second most common cause of esophageal varices worldwide.
• Genital sores — lesions that increase vulnerability to HIV infection. Lesions caused by schistosomiasis may continue to be a problem after control of the schistosomiasis infection itself. Early treatment, especially of children, which is relatively inexpensive, prevents formation of the sores.
• Skin symptoms: At the start of infection, mild itching and a papular dermatitis of the feet and other parts after swimming in polluted streams containing cercariae.

Occasionally central nervous system lesions occur: cerebral granulomatous disease may be caused by ectopic S. japonicum eggs in the brain, and granulomatous lesions around ectopic eggs in the spinal cord from S. mansoni and S. haematobium infections may result in a transverse myelitis with flaccid paraplegia.

Continuing infection may cause granulomatous reactions and fibrosis in the affected organs, which may result in manifestations that include:

• Colonic polyposis with bloody diarrhea (Schistosoma mansoni mostly);
• Portal hypertension with hematemesis and splenomegaly (S. mansoni, S. japonicum);
• Cystitis and ureteritis (S. haematobium) with hematuria, which can progress to bladder cancer;
• Pulmonary hypertension (S. mansoni, S. japonicum, more rarely S. haematobium);
• Glomerulonephritis; and central nervous system lesions.

Bladder cancer diagnosis and mortality are generally elevated in affected areas.