Review Question - QID 104528

Posterior urethral valves can lead to urethral obstruction, resulting in an inability to pass urine and a distended bladder, which is appreciated on physical exam as a midline mass.

A posterior urethral valve is a congenital defect in which an obstructing membrane develops in the male urethra. The membrane results in obstruction of the urinary system, a distended bladder, and subsequent midline mass in newborn male children. Posterior urethral valves can be associated with oligohydramnios as well as as lung hypoplasia, and they are the most common cause of bladder outlet obstruction in newborn males.

Fuloria and Kreiter discuss the newborn examination. They note that newborns with one anatomic malformation should be evaluated for additional abnormalities. Infants with craniosynostosis often require neurosurgical consultation. Facial nerve palsies often resolve spontaneously, and murmurs in the immediate newborn period are frequently innocent and a byproduct of the transition from fetal to adult circulation.

Casey et al. conducted a trial to examine the effects of oxybutynin administration on patients with posterior urethral valve ablation. They enrolled 18 patients at an average age of 3.4 months and treated them for a mean of 2.2 years. Patients with initial high voiding pressures had significant reduction in their voiding pressures, and patients with poor bladder compliance and low bladder capacity had significant improvements.

Illustration A is a picture of rocker bottom feet.
Illustration B is a diagram of the results of a congenital diaphragmatic hernia.

Incorrect Answers:
Answer 1: Rocker Bottom feet are seen in patients with trisomy 13 and trisomy 18.
Answer 2: A single palmar crease is associated with trisomy 21.
Answer 3: Bowel sounds in the thorax can be found in patients with congenital diaphragmatic hernias.
Answer 4: Polydactyly is associated with mutations in Sonic hedgehog proteins/genes.