Hypocalcemia Flashcards
Signs/Symptoms of HYPOcalcemia
Agitation Hyperreflexia (lower threshold) Convulsions/Seizures Hypotension Long QT Troussea sign chvostek sign Perioral parethesia
What can cause HYPOcalcemia
Hypoparathyroidism (Low PTH) High PTH (due to Vit D deficiency or Renal Disease) Drugs (bone resorption inhibitors) Low Mg Low albumin
How to diagnose Hypocalcemia
Measure urine/serum Ca+2 Measure PTH Measure Mg Measure Albumin Measure Vit D
How can Hypomagnesemia cause hypocalcemia
VERY low Mg can paradoxically activate CaSR and inhibit PTH release (thinks there is plenty of calcium)
Most common cause of HYPOparathyroidism
Post-Surgical (triggers autoimmune mediated activation of CaSR, inhibiting PTH release)
Cause of Hypoparathyroidism; AD inheritance of 22q11 deletion; failure of 3rd/4th branchial pouches to form, resulting in absence of Thymus and Parathyroids; can also see cardiac abnormalities, abnormal facies and cleft palate
DiGeorge Syndrome
What does the Mnemonic “CATCH-22” mean for DiGeorge Syndrome
Cardiac Abnormality Abnormal Facies Thymic Aplasia Cleft Palate Hypocalcemia/Hypoparathyroidism
How can Chronic Kidney Disease result in Hypocalcemia
Impaired Vitamin D activation, lowering Calcium absorption in gut (thus triggers an appropriate rise in PTH)
Cause of Hypocalcemia due to PTH resistance; due to an inactivating mutation of the GNAS gene (important for G proteins); results in brachydactyly (short fingers), round face, short stature and central obesity
Albright’s Hereditary Osteodystrophy
Signs/Symptoms of Vitamin D deficiency (either Rickets or Osteomalacia)
"Pigeon Chest"
Protruding sternum
"Rachitic Rosary" of ribs
Curved arm and leg bones ("bowed")
Looser-Milkman pseudofractures
