Hypophosphatemia occurs when the serum phosphorus level falls below 2.5 mg/dl.
Signs and symptoms of hypophosphatemia depend on the severity, associated deficiencies and underlying illness.
Mild to moderate hypophosphatemia is often asymptomatic and major clinical sequelae are usually seen only in severe hypophosphatemia.
Hypophosphatemia affects the musculoskeletal, central nervous system, cardiac and hematologic systems. With hypophosphatemia, muscle weakness is the most common symptom. Other symptom may include diplopia, malaise, and anorexia. The patient may experience a weakened hand grasp, slurred speech or dysphagia and also may develop myalgia.
Hypophosphatemia can cause rhabdomyolysis. This may be asymptomatic, manifested only by increased serum muscle enzyme levels or may cause severe muscle pain and weakness and acute renal failure.
Osteomalacia, loss of bone density and bone pain may occur with prolonged hypophosphatemia and can result in pathological fractures.
Respiratory insufficiency is common among severely hypophosphatemia patients. Respiratory failure may result from weakened respiratory muscles and poor contractility of the diaphragm.
Hypophosphatemia may also cause hemolytic anemia because of changes in the structure and function of red blood cells. Hypophosphatemia results in impaired production of 2,3-DPG in the erythrocyte, causing a leftward shift of the oxyhemoglobin dissociation curve and decreased tissue oxygen delivery.
Hypophosphatemia cause lack of ATP results in decreased leukocyte production, making the patient susceptible to infection.
Chronic hypophosphatemia also effects platelet function, resulting in bruising and bleeding, particularly mild GI bleeding.
What are symptoms of hypophosphatemia?
