uremia

Introduction

Elevated plasma urea. According to ref 3, uremia is a term reserved to the signs & symptoms of azotemia.

Clinical manifestations

• uremic signs & symptoms may become apparent as:
  • BUN rises above 100 mg/dL
  • glomerular filtration rate drops below
    • 30 mL/min in chronic renal failure (CRF)
    • 10 mL/min (most commonly)
    • 15 mL/min in diabetic patients
• neurologic manifestations
  • central nervous system
    • lethargy
    • seizures
    • myoclonus
    • asterixis
    • dysgeusia
    • delirium
    • sleep disturbances
  • peripheral neuropathies
    • more sensory than motor
    • pruritus
    • diminished vibratory sensation
    • hypoesthesia
    • diminished deep tendon reflexes (DTR)
    • restless legs syndrome
  • autonomic dysfunction
    • orthostatic hypotension
    • gastroparesis
• cardiovascular abnormalities
  • pericarditis (pericardial friction rub)
  • hypertension
  • accelerated atherosclerosis
• dermatologic abnormalities
  • pruritus
  • hyperpigmentation
  • acne
• gastrointestinal manifestations
  • nausea & vomiting
  • anorexia
  • pancreatitis
• hematologic manifestations
  • platelet dysfunction
  • abnormal B- & T-cell function
  • anemia
  • increased bleeding time
• fluid & electrolyte abnormalities
  • volume expansion
  • hyperkalemia
  • hypocalcemia
  • hyperphosphatemia
  • metabolic acidosis
• endocrine manifestations
  • impaired priduction of 1,25-dihydroxyvitamin D3
  • hyperparathyroidism
  • altered thyroxine metabolism
  • carbohydrate intolerance
    • resistance to insulin
    • resistance to growth hormone
  • decreased renal clearance of insulin
  • hypertriglyceridemia
  • hyperprolactinemia
  • decreased serum testosterone levels
• pulmonary:
  • uremic lung, a form of non-cardiogenic pulmonary edema
  • pleural effusion is common - generally transudative

Radiology

• chest X-ray
  • may show 'butterfly shadows', alveolar infiltrates limited to the inner 2/3 of both lungs with sparing of the peripheral areas
  • chest X-ray changes proportional to degree of azotemia & acidosis in acute renal failure

Complications

(see complications of uremia)

Management

• treatment of hypertension & hypervolemia
  • Na+ restriction < 1.5 g/day
  • antihypertensive agents
  • loop diuretics
• K+ restriction is generally required
• avoid magnesium-containing antacids
• correct acidosis: CaCO3 (doubles as phosphate binder)
• DDAVP first line for acute bleeding
  • also preopeoperative prophylaxis
• hemodialysis if evidence of uremic encephalopathy
  • hemodialysis improves platelet function & decreases bleeding
• conjugated estrogens can improve mucosal bleeding if DDAVP & hemodialysis are not effective
• platelet transfusions for active bleeding as needed
• epsilon aminocaproic acid for active bleeding as needed

More general terms

• azotemia

Additional terms

• complications of uremia
• urea in serum/plasma