Urinary bladder bilharziasis as a cause of impaired bladder muscle contractility.

In an attempt to evaluate the effect of bilharziasis on bladder contractility as a factor in the genesis of voiding disorders, 44 cases of bilharzial bladder neck obstruction diagnosed using traditional methods (symptomatological, radiographic, and endoscopic) were subjected to complete urodynamic evaluation (flowmetry, cystometry, pressure/flow study, and stop-flow test). Their parameters were compared with those of 28 patients with urodynamically obstructed benign prostatic hyperplasia and 8 nonsymptomatic controls. Contractility parameters (isometric detrusor pressure, maximum estimated flow rate, detrusor power at maximum flow) were calculated for the studied cases and their distribution according to the Schafer pressure/flow diagram was evaluated. Bladder biopsy including the detrusor was evaluated in all 72 patients. Poor bladder contractility associated with an extensive bilharzial effect on the detrusor muscle was found to be the major abnormality in 20 of 44 patients with presumed bilharzial bladder neck obstruction with no evidence of urodynamic outflow obstruction. We believe such a workup is essential in cases of suspected obstruction associated with bilharziasis to throw light on the pathophysiology of the voiding disorders, avoid unnecessary surgery, and provide a better prognosis.