The variability of urographic findings in posterior urethral valves.

The full variety of secondary and associated upper tract abnormalities concurrent with obstructive valves seems not to be generally appreciated. While upper urinary dilatation and impaired renal function are features regarded as almost obligatory, there are cases at the other end of the spectrum with surprisingly slight or no abnormalities of the bladder, ureters or collecting systems. Therefore a negative IVP does not exclude posterior urethral valves in any boy with symptoms pertaining to the urinary tract. A MCU should invariably be included in the radiological work-up.