To evaluate the prevalence of congenital urinary tract defects in Came
roonese children, the kidneys and urinary tract were investigated by u
ltrasound scanning in 55 children with a first documented episode of u
rinary tract infection. A Siemens unit with a 5 Mhz transducer was use
d. The appearance of transversal and longitudinal sections of both kid
neys was assessed, as well as the size of the kidneys, their contours,
the pyelocalyceal cavities, and corticomedullary differentiation; in
addition, dilation of the retrovesical portions of the ureters was loo
ked for. Thirty-nine sonograms (71%) were normal. Among the 16 abnorma
l sonograms, 12 (22%) showed minor defects (minor pyelocalyceal dilati
on) and four (7%) major defects (severe ureteropelvic junction obstruc
tion, n = 1; megaureter, n = 1 ; posterior ureteral valves, n = 2). Tw
o patients had evidence of acute pyelonephritis (focal bacterial nephr
itis in one case and diffuse pyelonephritis in the other). These data
are consistent with earlier studies suggesting that ultrasound evaluat
ion of the kidneys and urinary tract should be performed in both boys
and girls with a first urinary tract infection to look for urinary tra
ct malformations.