Hypocalcemia - Differential Diagnosis Algorithm • Low Serum Mg: GI losses, Renal losses, Alcoholism, Malnutrition, Drug-Induced • Intact PTH Level Elevated - Secondary Hyperparathyroidism: CKD/ESRD, Malabsorption, Vit D deficiency or resistance, Pseudohypoparathyroidism (PTH resistance) • Intact PTH Level Inappropriately Normal/Low - Hypoparathyroidism: Destruction of parathyroid glands (i.e. thyroid surgery, autoimmune), irradiation, infiltrative disease (very rare) • Low Serum 25-OH Vit D: GI losses, Low dietary intake, Low sunlight • Other Causes: Acute pancreatitis, Sepsis/severe illness, Hyperphosphatemia, Large volumes of blood (citrate chelates Ca2+) Emory IM Chiefs @emoryimchiefs #Hypocalcemia #Differential #Diagnosis #Algorithm #causes
