Functional Urinary Tract Obstructions

The article by Salvatierra et al on "Primary Vesicoureteral Reflux and End-Stage Renal Disease" (p 1454) in this issue shows an intelligent and praiseworthy attempt to urge more effort, on the part of the medical profession, to detect the underlying causes of renal failure in an early stage when effective treatment might be applied. It provides an opportunity to call attention to studies on functional obstruction of the urinary tract, which have been going on, relatively unnoticed, for some years.1-3The relations between structural obstruction (eg, stricture) and infection of the urinary tract are clear, but observers have been puzzled by many cases in which infection persisted despite the absence of any anatomical obstruction. Many have classified such cases as "nonobstructive infection." It has now been shown that spasm or hypertonicity of the external urethral sphincter can be a potent cause of urethral obstruction, undetectable by cystoscopic or roentgenographic