Vitamin C (Ascorbic Acid) Deficiency and Excess

Summary

Vitamin C (Ascorbic Acid) imbalances can occur as either deficiency or excess. Deficiency of Vitamin C results in the clinical syndrome of scurvy. Symptoms include easy bleeding, swollen gums, weakened immune response, anemia, and coiled or “corkscrew” hairs. The bleeding abnormalities can manifest as bruising, petechiae, hemarthrosis, subperiosteal and perifollicular hemorrhages. Vitamin C excess is rare and presents clinically with fatigue, nausea/vomiting, calcium oxalate kidney stones, and increased risk for iron toxicity (hemochromatosis).

Key Points

• Ascorbic Acid (Vitamin C) Deficiency
  • Rare in developed countries, but seen in malnourished (elderly, alcoholics, poor/homeless)
  • Clinical syndrome of scurvy
    • impaired collagen synthesis weakens vascular beds
      • subperiosteal hemorrhages
      • hemarthrosis (bleeding into joint spaces)
      • swollen, painful gums
      • bruising, petechiae, and perifollicular hemorrhages
    • poor wound healing
    • weakened immune response
    • anemia, coiled “corkscrew” hair also seen
• Ascorbic Acid (Vitamin C) Excess (low-yield)
  • diarrhea, abdominal bloating, nausea/vomiting, fatigue
  • increased risk of iron toxicity (transfusions, hemochromatosis)
    • via increased GI iron uptake (see Vitamin C Function)
  • may predispose to calcium oxalate nephrolithiasis

Find Vitamin C Deficiency and other Vitamins among Pixorize's visual mnemonics for the USMLE Step 1 and NBME shelf exams.