The answer is that the micturating cysto–urethrogram (MCUG) shows evidence of posterior urethral valves (PUV) and a diverticulum in the bulbous urethra
The Question:
The image is a micturating cysto–urethrogram (MCUG) performed (see picture) in an 18–month–old boy who presented with problems of urinary dribbling since birth, with fever, dysuria, straining on micturition and a lower abdominal mass. He had never passed urine with a normal stream. A physical examination revealed a distended bladder and normal genitalia. His serum urea level was 0.85 g/L (normal range 0.05–0.4 g/L) and creatinine level 27 mg/L (normal range 5–15 mg/L). Source: Dr. M. Zia–Ul–Miraj, Lahore Pakistan. BJU International 2000
Explanation
- PUV are the most common structural cause of urinary outflow obstruction in pediatric practice
- The most common type of obstructive uropathy leading to childhood renal failure
- 1 of every 5000 to 8000 male births
- 10% of prenatally diagnosed hydronephrosis
- 1 PUV in 1250 fetal ultrasound
- The etiology is not clear
- Children with PUV may demonstrate gradual loss of renal function over time
- The causes of renal insufficiency include:
- Renal parenchymal dysplasia
- Incomplete relief of obstruction
- Injury from a UTI
- HTN
- Progressive glomerulosclerosis from hyperfiltration
- Obstruction
- ESRD occurs in 25%-40%
- 1/3 soon after birth
- 2/3 during late teenager
