II. Causes
- Renal Failure
- Dehydration
- Addison's Disease
- Hypervitaminosis D
- Hypoparathyroid
- Magnesium Deficiency
- Milk-Alkali Syndrome
- Transfusions
- Hemolysis
- Sarcoidosis
- Bone metastases
- Myelogenous Leukemia
III. Evaluation: Renal Failure
-
Chronic Renal Failure
- Increased phosphate when GFR falls below 20 ml/min
- Usually Phosphate in 5-10 mg/dl range
-
Acute Renal Failure
- Especially in oliguric or hypercatabolic forms
- Highest in:
- Myoglobinuric Acute Tubular Necrosis
- Surgery
- Trauma
IV. Evaluation: Normal Renal Function
- Check Urinary phosphate excretion (Urine pHosphate)
- Increased Urine pHosphate: over 1500 mg/dl
- Endogenous source
- Cytotoxins
- Rhabdomyolysis
- Malignant hyperpyrexia (Fever)
- Exogenous source
- Endogenous source
- Normal Urine pHosphate: Under 1500mg/dl
- Increased reabsorption
- Hyperparathyroidism
- Menopause
- Extracellular Fluid Volume contraction
- Tumoral calcinosis
- Increased reabsorption
V. Management
-
Antacid binding gel: Aluminum hydroxide (AlternaGel)
- Dose 600 mg/5 ml, 5 ml qid with meals and at bedtime
- Low Phosphate diet