Handbook of Genetic Counseling/Vitamin C Deficiency

Vitamin C Deficiency

(Ascorbic Acid Deficiency, Scurvy)

General Information

 * 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

 * 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

 * 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

 * 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

 * 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

 * 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

 * 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

 * 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

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