Outcome and follow-up:
Based on the findings and treatment provided, it was recommended that
retransplantation of the ureters onto the bladder should be carried out
after three months. During the period of follow up there was not any
complications reported and no urinary infections were observed.
Discussion:
Posterior urethral valves (PUV) are the most common form of lower
urinary tract obstructions (LUTO) found in male pediatric patients. The
embryonic abnormality responsible for PUV formation remains unknown.
Some authors suggest that it may result from the abnormal fusion of the
mesonephric duct into the urethra, while others suggest it is due to the
persistence of the cloacal membrane. The overall incidence of LUTO is
approximately 3.3 per 10,000 pregnancies and 2.3 per 10,000 live births.
The overall prevalence is reported to be 3.34 per 10,000 births, ranging
from 2.95 to 3.72.3,6
About 35% of cases are diagnosed in utero, and these cases are
suspected when there is bilateral hydronephrosis, megacystis, and
oligohydramnion or anhydramnion. On the other hand, 42% of cases are
diagnosed during childhood, and the presenting symptoms include signs of
urinary obstruction and infection.3 Our patient
presented with loss of consciousness after a seizure; laboratory studies
revealed high levels of creatinine and urea consistent with
chronic kidney disease (CKD).
Further assessment showed that the patient had PUV.
The predominant presentation that persists in almost all patients with
PUV is voiding dysfunction (identified by poor stream, straining, and
dribbling). Additional features may include anemia, bladder distension
palpable above the pubic region, ascites, fever, ballotable kidneys, and
inability to thrive.4 Many complications can occur due
to the obstruction induced by PUV and it varies depending on the degree
of obstruction and the patient’s age. The obstruction can range from
minimal to severe resulting in bilateral severe hydroureteronephrosis
because of the high pressure above the valve placement, chronic kidney
disease (CKD) which may progress to
end-stage kidney disease (ESKD),
diverticular formation in the bladder, and even bladder rupture in
severe cases.7,8 Even though PUV manifests with
voiding dysfunction and CKD is considered a complication, our patient
presented with no signs or symptoms of voiding problems, and CKD was
detected during evaluation.
Micturating cysto-urethrogram
(MCUG) is the most useful technique for diagnosis. Ultrasonography is
considered an assistive diagnostic method especially for detecting
complications such as diverticular formation in the bladder and
hydroureteronephrosis.7,8 In this case,
MCUG was not able to detect the
valve which was then ablated during urethroscopy.
As we have seen in this case report, PUV can lead to an insidious
progressive chronic kidney disease even after years of birth. As we
know, PUV is not uncommon; therefore, practitioners should consider it
as a differential diagnosis for CKD in any child even if their age at
presentation is not typical. Moreover, heigh suspicion is needed if
diagnostic assessment investigations show normal findings as in this
case.