Wallach's Interpretation of Diagnostic Tests: Pathways to Arriving at a Clinical Diagnosis (1113 page)

   Most causes of hypocalcemia (except vitamin D deficiency, in which it is usually decreased)

   Increased tubular reabsorption or decreased glomerular filtration of phosphate

   Hypoparathyroidism (idiopathic, surgical, irradiation)

   Secondary hyperparathyroidism (renal rickets)

   Pseudohypoparathyroidism types I and II

   Other endocrine disorders (e.g., Addison disease, acromegaly, hyperthyroidism)

   Sickle cell anemia

   Increased cellular release of phosphate

   Neoplasms (e.g., myelogenous leukemia, lymphomas)

   Excessive breakdown of tissue (e.g., chemotherapy for neoplasms, rhabdomyolysis, malignant hyperthermia, lactic acidosis, acute yellow atrophy, thyrotoxicosis)

   Bone disease (e.g., healing fractures, multiple myeloma [some patients], Paget disease [some patients], osteolytic metastatic tumor in bone [some patients])

   Childhood

   Increased phosphate load: exogenous phosphate (oral or IV) form