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Vitamin C needs increased by fever, inflammation, diarrhoea, smoking, hyperthyroidism, Fe deficiency, cold or heat stress, surgery, burns, and protein deficiency.

About

• Always check BNF or equivalent for prescribing advice
• Scurvy is the clinical state from dietary deficiency of vitamin C (ascorbic acid)
• Humans cannot synthesize Ascorbic acid

History

• Limiting sea voyage, often killing many sailors after two to three months at sea.
• James Lind showed that scurvy could be cured by citrus fruits
• Ascorbic acid was first isolated by Albert Szent-Gyorgyi in 1928

Aetiology

• Vitamin C is an electron donor, or reducing agent
• Antioxidant protection against UV-induced photodamage to skin
• It results in impaired collagen synthesis as it is a co-factor for the proline and lysine hydroxylases that stabilise the collagen molecule tertiary structure
• Vitamin C also promotes collagen gene expression
• Clinical manifestations found in dentine, osteoid and capillary vessel wall tissues

Clinical

• Apathy, hypochondriasis and depression
• Gum swelling, friability, bleeding, and infection with loose teeth
• Mucosal petechiae; scleral icterus (late, probably secondary to haemolysis);
• Fractures, dislocations, and tenderness of bones are common in children.
• Bleeding into muscles and joints may be seen.
• Perifollicular hyperkeratotic papules, perifollicular haemorrhages
• Purpura, and ecchymoses are the classical skin manifestation of scurvy.

Differentials

• Osteoarthritis, ageing
• Haemorrhagic disorders and connective tissue/collagen diseases
• Gingivitis, and protein-energy malnutrition

Investigations

• FBC - may have anaemia
• Not commonly done but Vitamin C levels of < 0.2 mg/dL (< 11 mmol/L) indicate vitamin C deficiency.

Management

• This is primarily a disease of alcoholics and the elderly who consume <10 mg/d of vitamin C.
• Vitamin C replacement Ascorbic acid 100 to 500 mg po TDS is given for 1 to 2 wk and continued long term
• Five servings of most fruits and vegetables (recommended daily) provide > 200 mg/day of vitamin C.

References

• Ascorbic acid at BNF
• Review Article