Abdominal ultrasonography for assessing morbidity from schistosomiasis. 2. Hospital studies

Abdominal ultrasound, which uses a pulse echo device to record reflected waves of a sound beam in 2 dimensions, has revolutionized the evaluation of schistosomal morbidity. It is relatively inexpensive, rapid, simple to perform and portable, causes no biological hazards to the subject and, because of its speed, is ideal for diagnosis and directing interventions, e.g., biopsies. Ultrasound complements or replaces intravenous pyelography, cystoscopy, endoscopy, liver biopsy, angiography and other invasive techniques for studying morbidity due to schistosomiasis. The sensitivity and specificity of ultrasound, in comparison to these other procedures, for detecting schistosomal lesions has been between 80% and 100%, with the exception of detection of hydroureter, ureteral calculi and calcified bladder. Ultrasound is the best method for measuring liver and spleen size and configuration; detecting and grading periportal fibrosis, portal hypertension, hydronephrosis and urinary bladder wall lesions; and for demonstrating renal and bladder stones.