Category Archives: Renal disease

Renal failure

The term ‘renal failure’ means failure of renal excretory function due to depression of GFR. This is accompanied to a variable extent by failure of erythropoietin production , vitamin D hydroxylation, regulation of acid-base balance, and regulation of salt and water balance and blood pressure . ‘Acute renal failure’ means a decrease in renal function lasting days or weeks, whereas R

Drugs and the kidney

Drug-induced impairment of renal function Prerenal Impaired perfusion of the kidneys can result from drugs that cause: 1 Hypovolaemia due to: (a) Potent loop diuretics such as frusemide, especially in elderly patients (b) Renal salt and water loss, e.g. from hypercalcaemia induced by vitamin D therapy (since hypercalcaemia adversely affects renal tubular salt and water conservation) 2 Decrease in cardiac outp

Specific causes of obstruction

Pelviureteric junction obstruction This appears to result from a functional disturbance in peristalsis of the collecting system in the absence of mechanical obstruction. Surgical attempts at correction of the obstruction by open or percutaneous pyeloplasty should be limited to patients with recurrent loin pain and those in whom serial excretion urography, background-subtraction isotope renography or measuremen

Urinary tract obstruction

The urinary tract may be obstructed at any point between the kidney and the urethral meatus. This results in dilatation of the tract above the obstruction. Dilatation of the renal pelvis is known as hydronephrosis. AETIOLOGY Obstructing lesions may lie within the lumen, or in the wall of the urinary tract, or outside the wall, causing obstruction by external pressure. The major causes of obstruction are shown

INVESTIGATING THE CAUSE OF STONE

FORMATION In an elderly patient who has had a single episode with one stone, only limited investigation is required. Younger patients and those with recurrent stone formation require detailed investigation. AN EXCRETION UROGRAM is necessary to define the presence of a primary renal disease predisposing to stone formation. SIGNIFICANT BACTERIURIA may indicate mixed infective stone formation but relapsing bacte

CLINICAL FEATURES

Most people with urinary tract calculi are asymptomatic. Pain is the commonest symptom and may be sharp or dull, constant, intermittent or colicky. When urinary tract obstruction is present, measures that increase urine volume, such as copious fluid intake or diuretics, including alcohol, make the pain worse.Physical exertion may cause mobile calculi to move, precipitating pain and, occasionally, haematuria.

Calculi and nephrocalcinosis

Renal and vesical calculi Approximately 2% of the population in the UK have a urinary tract stone at any given time. A much higher prevalence of stone disease has been recorded elsewhere, notably in the Middle East. In the Western World, most stones occur in the upper urinary tract. The incidence of bladder stones has declined in the UK since the eighteenth and nineteenth centuries, whereas in some developin

Other vascular disorders of the kidney

Renal artery occlusion This occurs from thrombosis in situ usually in a severely damaged arteriosclerotic vessel or more commonly from embolization. Both result in renal infarction resulting in a wide spectrum of clinical manifestations depending on the size of the artery involved. Occlusion of a small branch artery may produce no effect but occlusion of larger vessels results in dull flank pain and varying 

Hypertension and the kidney

Hypertension can be the cause or the result of renal disease. It is often difficult to differentiate between the two on clinical grounds. Routine tests as described should be performed on all patients, but IVU is usually unnecessary. A guide to which patients should be fully investigated is given. ESSENTIAL HYPERTENSION PATHOPHYSIOLOGY In benign essential hypertension, arteriosclerosis of major renal arteries

Hyperuricaemic nephropathy (gouty nephropathy)

Three patterns of renal disease have been described III patients with hyperuricaemia or hyperuricosuria: 1 Gouty or chronic hyperuricaemic nephropathy 2 Acute hyperuricaemic nephropathy 3 Uric acid stone formation Chronic hyperuricaemic nephropathy Considerable controversy surrounds the possible role of chronic hyperuricaemia as a cause of tubulo-interstitial disease and progressive renal damage. While uric acid