DR. VIVEK M. REGE
PEDIATRIC SURGEON & PEDIATRIC UROLOGIST
REFLUX NEPHROPATHY
As described earlier, there are 2 kidneys – each has a pelvis, a ureter
that opens in the bladder. Normally, the flow of urine is from above
downwards only. In some children, it is possible that there may be in
addition, a flow of urine from below upwards into the ureter and the kidneythis is called Reflux of urine.
Reflux of urine has been known to cause a lot of major problems if
undetected and hence untreated. Some of these problems are easily treatable
by oral medications, but, some may require an operation to correct the
abnormality. Reflux is basically of 2 types i.e. Primary and Secondary.
Primary Reflux
Primary reflux is one in which there is no abnormality in the rest of
the urinary tract, except an abnormal junction of the ureter and the bladder.
1
HURKISONDAS HOSPITAL
B J WADIA HOSPITAL FOR CHILDREN
WOCKHARDT HOSPITAL
MOBILE: 98210 52680
Website: www.addlifesurgikids.com
DR. VIVEK M. REGE
PEDIATRIC SURGEON & PEDIATRIC UROLOGIST
Usually, the ureter does not join the bladder thru a hole – but, a part of the
ureter has a submucosal tunnel thru which is passes before opening in the
cavity of the bladder. This means after entering the bladder on the outer side,
it goes between the muscle and mucosal(innermost layer) of the bladder. The
length of the tunnel is about 3 –4 times the diameter of the ureter. This
submucosal tunnel acts as flap valve that gets compressed as the bladder fills
up with urine and prevents the urine from the bladder going up into the
ureter, at the same time it allows the urine from the ureter to enter the
bladder. In some children, if the submucosal tunnel length is too short or the
bladder muscle support is inadequate, the valve action cannot occur
efficiently and reflux can occur.
Secondary reflux occurs in those children where the junction of the
ureter and the bladder is normal, but, there are high pressures in the bladder
and the back pressure can allow the reflux of urine into the ureter(s). The
high pressures in the bladder may be due to an obstruction at the neck of the
bladder, or in the urethra from where the urine is ultimately expelled out of
the body. The high pressure in the bladder is transmitted backwards and can
cause the reflux. In a few children, there may be damage to the nerves
supplying the bladder and even less quantity of urine may generate very high
pressures and lead to reflux. Therefore it is important to know the cause of
the reflux and then traet the cause after a proper investigation.
Urethral valves with secondary reflux
Symptoms which make one suspect presence of a reflux in a child are
very common, non specific and subtle. The doctor must have a suspicion and
order investigations to prove the presence of the reflux. In a young infant
2
HURKISONDAS HOSPITAL
B J WADIA HOSPITAL FOR CHILDREN
WOCKHARDT HOSPITAL
MOBILE: 98210 52680
Website: www.addlifesurgikids.com
DR. VIVEK M. REGE
PEDIATRIC SURGEON & PEDIATRIC UROLOGIST
below 1 year age, there may be fever and urinary infection; or may come
with not thriving well – always ill, not putting on weight etc. In an older
child, there may be recurrent urinary infections occurring every month with
or without fever each time. There may be urinary symptoms like difficulty in
passing urine, burning, dribbling of urine, poor stream of urine and straining
to pass urine. Some children may have recurrent abdominal pain more at the
back or in the flank. Reflux of long standing and not diagnosed nor treated –
may cause a lot of complications. The damage is mainly to the kidney and
its function and part of the damage is permanent, part is reversible
depending on how early the diagnosis and therapy has begun. The effects of
the reflux will spell out how the damage occurs. Reflux of urine can occur
when the childs bladder begins to fill up with urine. Urine goes up into the
ureter, additionally, when the bladder is full and the child is straining to pass
urine, once again more urine goes up into the ureter. This urine is over and
above the normal urine that is formed within the kidney and is coming down
normally. Thus, the amount of urine in the ureter is more than normal and in
order to accommodate the excess volume, the ureter dilates stretches. This
will increase with time and more volumes of refluxed urine.The urine in the
ureter is now stagnant and will enter the bladder after the child has passed
urine and will remain there till the child wishes to pass urine again. This may
be a period of hours or more. Part of the stagnant urine may again go up in
the ureter and stagnate further. Stagnant urine is ideal for getting infected.
Thus the child is given treatment for the urinary infection, then the antibiotic
is stopped, but the process of reflux continues and after a lapse of a few day
or weeks, the infection recurs and the cycle goes on. Reflux has been graded
from 1 to 5. Higher the grade of reflux, the higher the urine goes up and into
the kidney tissue due to the high pressure. Reflux pressure and the infection
together hits the kidney substance and deposit the bacteria within the kidney
tissue to cause an infection called Pyelonephritis. This infection can
damage the kidney and if left untreated or incompletely treated, may lead to
a permanent damage to the kidney on one or both sides and finally lad to
renal failure which responds to Dialysis and later a renal transplant.
Pyelonephritis can also be a cause of high blood pressure due to various
mechanisms, and in all children will lead to stoppage of growth of the
kidney in all dimensions.
Investigations are done based on suspicion and the most important 2
investigations are Ultrasound(USG) of the kidneys, ureters, and bladder;
followed by a Voiding Cysto Urethrogram(VCU).
3
HURKISONDAS HOSPITAL
B J WADIA HOSPITAL FOR CHILDREN
WOCKHARDT HOSPITAL
MOBILE: 98210 52680
Website: www.addlifesurgikids.com
DR. VIVEK M. REGE
PEDIATRIC SURGEON & PEDIATRIC UROLOGIST
The USG will show the shape, size thickness of the kidneys, presence
of dilatation of the ureters, and the bladder wall thickness, residual urine etc.
The VCU is the next investigation wherein a small tube is passed into
the urethra of the child upto the bladder and the bladder is filled with a
contrast liquid that is seen as white on a x ray picture. When the bladder is
full one x ray is taken to look for the shape, size of the bladder, any reflux is
present can also be seen and graded. Next the tube is removed from the
bladder and the child is asked to pass urine and a second x ray is taken as the
child is passing urine. This will show the presence of reflux if it occurs only
during straining; it will also show the shape and size of the urethra, any
obstruction at the bladder neck or in the urethra that may be the primary
cause.
Neither of thee investigations tells us the individual function of the
kidneys which is essential to know before therapy is begun. This will act as a
baseline for later studies to show improvement in function after proper
therapy or may show no improvement that may indicate permanent damage
has already occurred. This can be done by doing a Radio Nuclear study
called DMSA Scan of the kidneys. Here, the radioactive material is injected
into the child intravenously and the pictures are taken at intervals and
charted. This investigation will tell the individual function of each kidney(
normal should be 50%). This will also show non functioning areas of the
kidney as “cold” areas suggesting damage to that part of the kidney. The
more the cold areas, the worse is the prognosis, and lower the percentage
function of the kidney, worse is the prognosis. Serial Scans will show
improved function if the treatment is successful and others may show no
change in percentage or may even show falling percentage leading to a renal
failure.
Treatment of Primary reflux depends on the severity, the time of
diagnosis(age), and kidney function at the time of diagnosis. Certain basic
principals are followed in therapy: one is that reflux by itself is not harmful
or dangerous, but, together with infection can cause severe renal damage;
secondly, reflux that is picked up early will have caused les damage than one
picked up later – this is because reflux has been present since birth; and
thirdly, reflux is known to decrease in grade and even disappear with
increasing age of the child, so if we wait for an adequate time without
allowing infection to occur, there may be no reflux after a few years later.
The last and most important principal is to prevent infection and reflux may
take care of itself. Thus the therapy for grade 1 - 3 reflux in children with
4
HURKISONDAS HOSPITAL
B J WADIA HOSPITAL FOR CHILDREN
WOCKHARDT HOSPITAL
MOBILE: 98210 52680
Website: www.addlifesurgikids.com
DR. VIVEK M. REGE
PEDIATRIC SURGEON & PEDIATRIC UROLOGIST
adequate renal function is prevention of infection: this is done by giving a
long term, low dose antibiotics to the child for a period of 3 – 4 years under
proper supervision and regular check ups The indications for change in
therapy in these children are – urinary infections despite regular antibiotics,
if grade of reflux is 4 – 5, if kidney function is severely affected to start
with. The only alternate therapy in these cases is surgical correction of the
reflux. Surgery for reflux is called a reimplantation of the ureter into the
bladder. This is a very major surgery where the ureter is disconnected from
the original position, and a fresh tunnel is made within the bladder and the
ureter is taken thru this and sutured to the bladder at a different position. The
new tunnel must be at least 3 – 4 times the diameter of the ureter to avoid a
reflux post operatively. Tubes are kept to drain the urine from the kidneys
directly in the ureter. These tubes may be removed after 10 days. The child
stays in the hospital for 10 – 12 days before being sent home after removal
of all sutures.
Ureter before reimplantation
5
HURKISONDAS HOSPITAL
B J WADIA HOSPITAL FOR CHILDREN
WOCKHARDT HOSPITAL
MOBILE: 98210 52680
Website: www.addlifesurgikids.com
DR. VIVEK M. REGE
PEDIATRIC SURGEON & PEDIATRIC UROLOGIST
Making a submucosal tunnel in bladder for ureter
Complications associated with this surgery are – infection of the
main wound , leak of urine around the tubes instead of thru them, the
bladder that had been opened for the operation may leak urine outside. Late
complications of this procedure are recurrence of the reflux if the tunnel
length is inadequate, inappropriate, or due to infection damage; the other is
narrowing at the new junction of the ureter an the bladder leading to
obstruction of urinary flow and dilatation of the ureter with back pressure
on the kidney and damage.
The therapy of secondary reflux is naturally treatment of the basic
cause like obstruction distal to the bladder, abnormal bladder function
treatment with specific drugs. In most cases, therapy of the primary cause
and patience will allow the reflux to subside on it own and no specific
therapy is required. If the reflux persists or its complication occurs then it
will be necessary to treat the reflux also as has been just described
6
HURKISONDAS HOSPITAL
B J WADIA HOSPITAL FOR CHILDREN
WOCKHARDT HOSPITAL
MOBILE: 98210 52680
Website: www.addlifesurgikids.com