II. Symptoms

  1. Cardiovascular (Systolic Dysfunction)
    1. Dyspnea
    2. Edema
    3. Palpitations
    4. Syncope
  2. Neurologic
    1. Headache
    2. Muscular fasciculations, muscle cramping or spasms, muscle stiffness
    3. Seizures
    4. Paresthesias
    5. Circumoral numbness
    6. Nervousness
    7. Weakness
  3. Gastrointestinal
    1. Vomiting
    2. Diarrhea
    3. Dysphagia
    4. Abdominal Pain

III. Signs

  1. Neurologic
    1. Tetany
    2. Carpopedal Spasm (Trousseau's Sign)
    3. Chvostek's Sign
  2. Skin
    1. Hair Loss (due to dry, brittle hair)
    2. Dry, puffy skin
  3. Eyes
    1. Premature Cataracts
    2. Papilledema

IV. Diagnostics: EKG

V. Labs

  1. Serum Calcium low
    1. Total Corrected Serum Calcium (for Serum Albumin) or
    2. Ionized Calcium
  2. Serum electrolytes
    1. Serum phophate
    2. Serum Magnesium
    3. Serum Creatinine
  3. Parathyroid Hormone (PTH)
  4. Vitamin D
    1. 25-Hydroxyvitamin D
    2. 1,25-Dihydroxyvitamin D

VI. Causes

  1. Miscellaneous and Multifactorial causes
    1. Hypoalbuminemia
      1. Use Corrected Serum Calcium for albumin or Ionized Calcium to interpret calcium level
    2. Gram-Negative Sepsis (Marker for increased Sepsis related mortality)
      1. Zaloga (1987) Ann Intern Med 107(1): 36-41
  2. Low Parathyroid Hormone (or normal Parathyroid Hormone level)
    1. Hypoparathyroidism
      1. Urine Calcium to Creatinine Ratio decreased
    2. Hypomagnesemia
    3. Calcium-sensing receptor activating mutation
      1. Serum Phosphorus increased
      2. Urine Calcium to Creatinine Ratio increased
  3. High Parathyroid Hormone (secondary Hyperparathyroidism as a reflex response to Hypocalcemia)
    1. Low serum phosphate
      1. See Medication-Induced Hypocalcemia
      2. Pancreatitis
      3. Vitamin D Deficiency
        1. Decreased 25-hydroxyvitamin D
    2. High or normal serum phosphate
      1. Acute Renal Failure or Chronic Kidney Disease
        1. Decreased 1,25-dihydroxyvitamin D
      2. Rhabdomyolysis
      3. Tumor lysis
      4. Pseudohypoparathyroidism
        1. Associated with adequate PTH levels, but a PTH receptor defect
        2. Associated with a shortened fourth digits on the hands and feet

VII. Evaluation

  1. Confirm Hypocalcemia
    1. Obtain Corrected Serum Calcium (for Serum Albumin) or Ionized Calcium
  2. Obtain labs to narrow causes (see labs above)
    1. Parathyroid Hormone
    2. Serum electrolytes (Serum phosphate, Serum Magnesium, Serum Creatinine)
    3. Vitamin D (25-Hydroxyvitamin D, 1,25-Dihydroxyvitamin D)
  3. Initial correction of abnormalities (if indicated)
    1. Correct Serum Magnesium if abnormal
    2. Immediate Calcium Replacement if symptomatic
  4. Identify underlying cause
    1. See causes above (based on lab findings as well as history and exam)

VIII. Management

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Ontology: Hypocalcemia (C0020598)

Definition (NCI) Lower than normal levels of calcium in the circulating blood.
Definition (NCI) A disorder characterized by laboratory test results that indicate a low concentration of calcium in the blood.
Definition (MSH) Reduction of the blood calcium below normal. Manifestations include hyperactive deep tendon reflexes, Chvostek's sign, muscle and abdominal cramps, and carpopedal spasm. (Dorland, 27th ed)
Definition (CSP) reduction of the blood calcium below normal; manifestations include hyperactive deep tendon reflexes, muscle and abdominal cramps, and carpopedal spasm.
Concepts Pathologic Function (T046)
MSH D006996
ICD9 275.41
ICD10 E83.51
SnomedCT 5291005, 154752005, 267505006
English Hypocalcemias, CALCIUM BLOOD DECREASED, HYPOCALCAEMIA, HYPOCALCEMIA, hypocalcemia, hypocalcemia (diagnosis), Hypocalcemia, Blood calcium decreased, Calcium blood decreased, Hypocalcemia [Disease/Finding], abnormally low blood calcium levels, Calcium deficiency disease, Hypocalcemia syndrome, Hypocalcaemia, Hypocalcaemia syndrome, Hypocalcemia (disorder), hypocalcaemia
French HYPOCALCEMIE, Calcium sanguin diminué, DIMINUTION DE LA CALCEMIE, Calcémie diminuée, Hypocalcémie
Portuguese HIPOCALCEMIA, Cálcio no sangue diminuído, DIMINUICAO DA CALCEMIA, Calcemia diminuída, Hipocalcemia
Spanish HIPOCALCEMIA, Calcio disminuido en sangre, Hypocalcaemia, Hypocalcemia, CALCEMIA DISMINUIDAD, enfermedad por deficiencia de calcio, hipocalcemia (trastorno), hipocalcemia, síndrome de hipocalcemia, síndrome hipocalcémico, Calcio en sangre disminuido, Hipocalcemia
German HYPOKALZAEMIE, KALZIUMBLUTSPIEGEL VERMINDERT, Hypokalzaemie, Kalzium im Blut erniedrigt, Hypocalcaemia, Hypokalzämie
Dutch calcium bloed verlaagd, bloed calcium verlaagd, hypocalciëmie, Calciëmie, hypo-, Hypocalciëmie
Japanese 低カルシウム血症, 血中カルシウム減少, テイカルシウムケツショウ, ケッチュウカルシウムゲンショウ, テイカルシウムケッショウ
Swedish Hypokalcemi
Czech hypokalcémie, Kalcium v krvi snížené, Snížený vápník v krvi, Hypokalcemie
Finnish Hypokalsemia
Russian GIPOKAL'TSIEMIIA, ГИПОКАЛЬЦИЕМИЯ
Italian Calcio ematico diminuito, Ipocalcemia
Polish Hipokalcemia
Hungarian Kalcium vérszint csökkent, Hypocalcaemia

Ontology: Serum calcium decreased (C0595882)

Concepts Finding (T033)
English SERUM CALCIUM DECREASED, Calcium Serum Decreased, Calcium serum decreased, Serum calcium decreased
Dutch calcium serum verlaagd, serum calcium verlaagd
French Calcium sérique diminué
German Kalzium im Serum erniedrigt
Italian Calcio sierico diminuito
Portuguese Cálcio do soro diminuído, Cálcio sérico diminuído
Spanish Calcio disminuido en suero
Japanese 血清カルシウム減少, ケッセイカルシウムゲンショウ
Czech Snížené kalcium v séru
Hungarian Kalcium szérumszint csökkent, Szérum kalcium csökkent