Posterior urethral valve: A case report in an older Nigerian child

Abstract

Posterior urethral valve (PUV) is an anomaly of the urinary tract in male children and is the leading cause of urinary tract obstruction in the pediatric population. PUV is diagnosed radiologically by ultrasonography, both pre- and postnatally, and using micturating cystourethrography. Its prevalence and age of diagnosis may vary by demographic and ethnic background. This case highlights an older Nigerian child that presented with recurrent urinary tract symptoms and was subsequently diagnosed with PUV. The study further explores the key radiographic findings and analyzes the radiographic imaging features of PUV in various populations.

Keywords: DMSA; Genitourinary imaging; MCUG; Posterior urethral valves; Urinary tract infections.

Fig. 1

Sagittal B- mode ultrasound scan of the abdomen showing enlarged kidneys with multiple communicating anechoic structures within them (calyces-star) and both renal pelvis (cross). There is also associated complete thinning of the renal parenchyma bilaterally.

Fig. 2

Transverse scan of the pelvis showing the urinary bladder (cross) with thickened walls and irregular outline (trabeculation) as well as dilated distal ureters (star).

Fig. 3

Sagittal and transverse B- mode ultrasound scan of the pelvis showing the urinary bladder (star) with low level echoes within it. It also shows thickening of its wall with irregularity of its outline (trabeculations- block arrows).

Fig. 4

Sagittal and transverse B- mode ultrasound scan of the pelvis showing the urinary bladder – post void (star). The urinary bladder contained significant post void residual volume (291 mL) with low level echoes within it.

Fig. 5

Bladder view of a micturating cystourethrogram (MCUG) showing a well distended urinary bladder, with irregularity of its outline indicative of trabeculations (block arrow). It also shows multiple tiny outpouchings consistent with diverticular formation with the largest seen on the right lateral wall (bent arrow).

Fig. 6

Micturating cystourethrography (MCUG) showing a dilated and elongated posterior (prostatic) urethra giving the “spinning top” appearance (block arrow), with a transverse filling defect seen within it consistent with a posterior urethral valve (bent arrow). The anterior urethra (curved arrow) shows a normal caliber and smooth outline.