Features of Renal Disease

Clinical Features

The clinical features of renal disease include the following:

  • Changes in urine output that include reduced urinary output (oliguria, anuria), increased urinary output (polyuria), increased frequency without increased volume.
  • Oedema of the body, usually facial initially but later involving legs and generalized.
  • Haematuria that ranges from microscopic to gross. Haematuria is a serious sign of disease and should be aggressively investigated. Causes include infections (urinary tract infection, tuberculosis, schistosomiasis), acute glomerulonephritis, trauma, meatal ulcers, blood disorders (bleeding disorders, leukaemia, purpura, sickle cell disease), tumours, scurvy, congenital
  • The blood pressure may be raised in some conditions or it may be a terminal manifestation in some conditions.
  • Renal masses may be palpable, for example if the patient has nephroblastoma, polycystic kidneys, horse-shoe kidneys, neuroblastoma, and hydronephrosis.

Laboratory Findings

The following laboratory findings may be found in renal disease:

  • Pyuria of >10 cells/mm3 in uncentrifuged urine specimen.
  • Casts of renal tubules formed by red blood cells (RBC), white blood cells (WBC), epithelial cells. The casts may be granular or hyaline.
  • Proteinuria that may vary from minimal to gross.
  • High blood urea or blood urea nitrogen (azotaemia, BUN) that accompany renal failure.
  • Raised blood creatinine levels that accompany renal failure.
  • Hyperkalaemia: Usually, there are no clinical consequences until the levels rise to 6mmol/L and above. Clinical features of hyperkalaemia include muscle weakness, abdominal distension, tingling of the face and of the muscles on the
    hands and feet, and irregular pulse, heart block, and increased amplitude of the T-wave on the ECG.