Children with single kidney
What is single kidney status?
This refers to a condition where instead of two kidneys, like everyone
else, the patient has only one kidney. Single kidney status may be due
Few children are born with a single
kidney. How does it happen? How common is this problem?
One of the kidneys will
fail to form/develop during the intra uterine period itself. So they
will be born only with a single kidney. Apart from defect in the
development, other causes like poorly controlled diabetes mellitus in
the mother, drugs like angiotensin converting enzyme inhibitors and high
dose vitamin A during pregnancy are the few risk factors for this
It can happen in 1 in
500 to 1000 live births. Often ultrasound (before birth) picks up the
absence of a kidney. There is no need to panic, if one
kidney is normally detected and the liquor volume is normal. After birth
a repeat ultrasound is performed to see whether the antenatal scan
findings are confirmed. If at this stage both kidneys can be detected no
further testing is required. If the ultrasound after birth also confirms
the single kidney status, this has to be further confirmed with a
definitive test like DMSA/CT scan, as an ultrasound often misses to pick
up a kidney that is located in the pelvis.
we have the kidney in some other part of the body instead of it in the
Yes. In some
individuals, one of the kidneys will be placed in lower position and may
not be detected by ultrasound.
It may also be crossed
to the opposite side with both kidneys fused one below the other
(crossed fused ectopia).
To find out this, we have other tests like DMSA/ CT.
Is it possible to live
with a single kidney? Do they need kidney transplant?
You can lead a normal
life with single kidney provided that the existing kidney has proper
growth and function. They do not need a kidney transplantation as the
single functioning kidney is often enough to clear the waste products
and sustain normal life. (This is the reason how normal individuals with
two kidneys are able to donate one kidney). Those with single kidney
status obviously can not donate it!
it be familial and run in families? Do we have to screen the other
family members? Do they have any associated abnormalities?
Yes. It can be familial
also. It is advisable to screen the parents and siblings of children
born with single kidney with ultrasound for renal anomalies. They can
have associated Vesico ureteric reflux. Even if
the ultrasound is normal, this needs to be ruled out if the child
develops urinary tract infection with the help of a test called MCU.
the ultrasound shows evidence for 2 kidneys with variation in size
during pregnancy, but once the baby is born, doctors say that only one
kidney is functioning. Is it possible to get that scenario?
Yes. Cysts in the
kidneys are non functioning tissues. Hence though we see the kidney by
USG as small, that may have only minimal/nil function. To prove that we
may need further imaging studies.
the children with single kidney need regular follow up?
should be followed up at regular interval with a pediatric nephrologist.
Blood pressure, height, weight and urine protein should be checked every
6 months. Annually renal function test has to be checked. Children with
renal dysfunction require more frequent visit depending upon the stage
of the renal disease.
they participate in sports?
can participate. But activities which are prone to cause kidney injury
need to be restricted are sports like boxing, skiing, snowboarding.
Apart from these, they should be encouraged to engage in some form of
will be the prognosis in children with single kidney?
uncomplicated single kidney usually will do well. Any disease in the
single existing kidney, will have varied prognosis depending on the
function of that kidney. Risk of hypertension, protein loss in urine and
hypertension during pregnancy are high compared to normal population.
they need any restriction in food intake?
They can have normal
salt diet, fluids, proteins and calories which are important for their
growth. In case of renal dysfunction and associated hypertension, diet
should be modified restriction of salt and fluid according to the stage
of the disease.
case of illness can they be shown to any other doctor? Any contra
indication for drugs?
Yes. But you should
reveal the single kidney status of your child. Avoid NSAIDS(pain
killers) and contrast agents.
Aminoglycosides (gentamicin/amikacin) may need careful
monitoring of dose and levels to prevent damage to the only kidney
functioning. Several native medications (siddha, ayurveda etc) may have
multiple ingredients that could potentially damage the kidney and are
case of necessity, get the advice of the pediatric nephrologist.