Handbook of Genetic Counseling/Vitamin C Deficiency

Vitamin C Deficiency

(Ascorbic Acid Deficiency, Scurvy)

General Information edit

  • Vitamin C is reducing agent that is easily oxidized or destroyed by heat
  • Deficiency can cause defects in collagen formation
  • Adrenal glands and lenses have high concentrations of Vitamin C

Etiology edit

  • Infants born with adequate stores of Vitamin C if mother's intake was good
    • Breast milk also provides adequate source of Vitamin C
    • Infants not breastfeeding or whose mothers are deficient require supplements
  • Majority of cases occur from 6-12 months
  • Febrile illnesses increase need for Vitamin C
    • Particularly infectious or diarrheal diseases
    • Iron deficiency, cold exposure, protein depletion, and smoking also increase need for intake of Vitamin C

Pathology edit

  • Collagen formed during deficiency is low in hydroxyproline
    • Leads to hemorrhage, defective tooth dentin, and loosening of teeth
    • Endochondral bone formation ceases
    • Bones may become brittle and fracture easily
  • Periosteum becomes loosened and hemorrhages in femur and tibia common
  • Degeneration in skeletal muscles, cardiac hypertrophy, bone marrow depression, adrenal atrophy if severe.

Clinical Manifestations edit

  • Begins with irritability, tachypnea, digestive disturbances, and loss of appetite
  • General tenderness, especially in legs
    • Pain causes pseudoparalysis with legs in "frog position"
    • Swelling and hemorrhage along legs
  • Face appears apprehensive, gums swollen
  • Depression of sternum
  • Petechiae in skin or mucous membranes
  • Hematuria, melena, orbital, or subdural hemorrhages
  • Anemia due to inability to utilize iron or impairment in folic acid metabolism
  • Swollen joints

Roentgenographic Manifestations edit

  • Usually basis of diagnosis of Vitamin C deficiency
  • Changes in long bones especially at knee
    • Begin as simple atrophy
    • Zone of well calcified cartilage appears as thick, irregular white line around bone
    • Difficult to diagnose at this stage
  • Subperiosteal hemorrhages at ends of bone may become more intense as deficiency becomes more severe

Diagnosis edit

  • Based mainly on clinical findings and history of poor intake of Vitamin C
  • Laboratory tests not very good index
  • Can get estimate from amount of urinary excretion of Vitamin C after test does of ascorbic acid
    • Children with deficiency secrete less ascorbic acid than those without
    • Check concentrations 3-5 hours after administration of test dose

Differential Diagnosis edit

  • Arthritis or acrodynia due to pain in limbs exacerbated by movement
  • Rheumatic fever - rare in children under 2 years of age
  • Suppurative arthritis and osteomyelitis
  • Syphilis due to pseudoparalysis - usually occurs at earlier age and has other symptoms
  • Polio - doesn't cause tenderness in limbs
  • Henoch-Schonlein purpura, thrombocytopenic purpura, leukemia, meningococcemia, nephritis also may be considered

Prognosis edit

  • Recovery rapid when treated correctly
    • Pain ceases within few days
    • May take months for subperiosteal hemorrhage to disappear
    • Body growth resumes quickly
  • Unrecognized/untreated cases may lead to death
    • From malnutrition, exhaustion, intercurrent disease
    • Uncommonly have permanent deformity

Treatment edit

  • Can be prevented by providing formula fed infants 25-50 mg ascorbic acid daily
    • Lactating mothers should have minimum intake of 80 mg per day
    • Children and adults need 50 mg per day
  • Therapeutic dose of ascorbic acid is 100-200 mg daily

Reference edit

"Vitamin C (Ascorbic Acid) Deficiency." Textbook of Pediatrics (1979):225-228.

Notes edit

The information in this outline was last updated in 2002.