INSTRUCTION

Examine this patient's abdomen.

SALIENT FEATURES

History

· Nephrectomy.

· Congenital absence of kidney.

· History of azotaemia, dialysis.

Examination

One kidney is palpable (bimanually ballottable; there is a transverse band of colonic resonance on percussion and you will be able to

insinuate your fingers between the mass and costal margin).

Proceed as follows:

Look carefully for arteriovenous fistulas in the arms, haemodialysis catheters in the subclavian region.

DIAGNOSIS

This patient has a unilateral palpable kidney (lesion) which may be due to either polycystic kidney disease or renal neoplasm

(aetiology).

QUESTIONS

What are the common causes of a palpable kidney?

· Polycystic kidney disease.

· Renal carcinoma.

· Hydronephrosis.

· Renal cyst.

· Hypertrophy of the solitary functioning kidney.

What changes can occur in a kidney when the other is removed?

Long-term renal function remains stable in most patients with a reduction in renal mass of more than 50%. However, these patients

are at increased risk for proteinuria, glomerulopathy and progressive renal failure. Hence it is important to monitor patients with

remnant kidneys. Problems are most frequent in those in whom the amount of renal tissue removed is greatest and who have

survived the longest (N Engl J Med 1991; 325: 1058).

Leon Fine, contemporary Professor and Chair of Medicine, University College Hospital, London.

Graeme Catto, contemporary Professor of Renal Medicine and Dean, Aberdeen Medical School.

H.A. Lee, retired Professor of Renal Medicine, Portsmouth, University of Southampton, who is also interested in metabolism.