Dear Putorius:
 
>Brando is our 3 year old sable (fixed) and has undergone surgery once for
>a polycystic kidney condition.  It was "drained/reduced" and life went
>back to normal...he resumed gaining weight and all was well for about a
>year.  As in Poltergeist..."it's baaacccckkk" ... loss of weight although
>he is actively eating and playing.  He's a little sluggish in the am and
>wakes up soooo slow...and tires easily as well.  He was seen today for
>annual shots and checkup and our vet did concur with me that he is losing
>a bit of muscle now... we will put him back on a high fat/protein diet ala
>duck soup and try to get his weight back up before if and when he has to
>be operated on again.  We would like to ask you about general prognosis,
>treatment, resources etc.  Of course he was operated on once and it
>appears to be necessary again...are there other options without employing
>the invasive technique every year or so.  The cyst is about the same size
>as before and is on the left side.
 
From what you are telling me, it sounds like a simple renal cyst, rather
than true polycystic disease.  In true PKD, both kidneys are riddled with
cysts, and usually before the ferret reaches two years of age, it has died
of renal failure.
 
Now probably 25% of ferrets have single large cysts in their kidneys.  Even
when they reach a large size, the kindeys continue to function normally.
(you have to lose 75-90% of functional kidney before it shows up in any
bloodwork.  This is generally not a life-threatening condition, and I've
never seen one rupture (the renal capsule is really a tough thing.)
 
So what do we do here?  Three possibilities -
1) - same surgery - go in and drain it, but it will just reform again.
2) Remove the kidney.  Ferrets do well with only one kidney, and this is
   not uncommonly done.
3) If your vet has a good ultrasound machine and is quite skilled at
palpation and ultrasound, a transcutaneous drainage of the cyst (placing
the needle through the body wall into the cyst) is another possibility.
 
My recommendation is probably to do the removal.
 
With kindest regards,
Bruce Williams, DVM
[Posted in FML issue 3317]