>... The appearence is of reactive fibrosis closely associated with the
>ureter and possibly early hydronephrosis.  The small area of calcification
>may be the result of ischaemic necrosis...
 
Dear X:
 
Much as we had thought going in, this is not a case of a traditional renal
cyst, nor is it a case of polycystic disease.
 
The gross description of a collapsed cyst-like structure suggests that
there is little functional renal tissue left, and that we have at best a
remnant surrounded by that tough renal capsule.
 
Most telling here is the dilated ureter (the pipe that connects the
kidney to the bladder).  This tells us that there is obstruction
downstream, what type apparently was not seen on the slide.
 
This is pretty classic hydronephrosis, and in ferrets, it usually is the
result of a bacterial urinary tract infection with obstruction of the
ureter by inflammatory debris and scarring.
 
With kindest regards,
Bruce Williams, DVM
[Posted in FML issue 3736]