Scurvy (vitamin C deficiency) — SAQ

Stem

A 68-year-old widow who lives alone presents with a three-month history of progressive bruising on her shins, bleeding gums on brushing, fatigue, and a non-healing ulcer on her right leg. Her diet consists almost entirely of tea and toast since her husband died. Examination reveals perifollicular purpura on the shins and dorsal feet, corkscrew hairs on the thighs, swollen spongy interdental papillae that bleed on probing, and a 4 cm sloughy leg ulcer. PT 12 s, APTT 31 s, platelets 240 × 10⁹/L, Hb 92 g/L, MCV 78 fL.^[1]

Questions

a) What is the most likely diagnosis and what three features support it? (2 marks)

Scurvy (severe vitamin C / ascorbic acid deficiency).^[1][3] Supported by: (i) a tea-and-toast diet for months (the dietary risk factor); (ii) the cutaneous tetrad of perifollicular purpura, corkscrew hairs, and follicular hyperkeratosis on dependent limbs; (iii) bleeding, hypertrophied gums with normal PT, APTT, and platelets (mechanical, not haematological, bleeding).

b) Outline the pathophysiology. (2 marks)

Vitamin C is an essential cofactor for prolyl-4-hydroxylase and lysyl hydroxylase, the endoplasmic-reticulum enzymes that hydroxylate proline and lysine during collagen post-translational maturation.^[3] Without hydroxylation, the collagen triple helix is unstable at body temperature, cross-linking fails, and defective collagen is secreted. The clinical consequence is capillary-wall fragility (perifollicular purpura, bleeding gums), poor wound healing (leg ulcer), and twisted hair shafts (corkscrew hairs). Humans lack L-gulonolactone oxidase, so vitamin C is a true dietary essential; stores last 1 to 3 months.

c) List four investigations and the expected result. (2 marks)

• Plasma ascorbic acid: under 11.4 micromol/L (the NHANES working definition of deficiency; sample on ice, protected from light).^[3]
• Full blood count: microcytic anaemia (here, Hb 92, MCV 78 — coexisting iron deficiency); platelets NORMAL.
• Coagulation: PT and APTT NORMAL (excludes coagulopathy).
• Iron studies, folate, B12: likely co-deficient (microcytosis indicates iron deficiency).

d) Outline the management. (4 marks)

• Replacement: oral ascorbic acid — published adult regimens use 500 mg to 1 g daily (500 mg daily resolved skin lesions fully within two weeks; 1000 mg daily gave dramatic gingival resolution); children 1 g/day with resolution within 48 to 96 hours.^[1]
• Co-deficiencies: oral iron for the microcytic anaemia; folate and B12 supplementation; screen and treat zinc, vitamin D, thiamine.
• Wound care: dressings for the leg ulcer; dental review for the gum disease.
• Address the cause: dietetic referral, social work for isolation and meals support, written dietary advice (citrus, peppers, kiwi, strawberries, broccoli).
• Follow-up: expect clear improvement within the first days (48 to 96 hours to symptom resolution in children on 1 g/day), adult skin lesions resolved within about two weeks, and hairs to normalise over 1 to 3 months.

References3ShowHide

1. [1]Toscano F, et al. Scurvy, all the faces you can see: our experience and review of the literature. Italian journal of pediatrics, 2025.PMID 40437614
2. [2]Reikersdorfer KN, et al. The Troubling Rise of Scurvy: A Review and National Analysis. JAAOS Global research & reviews, 2024.PMID 39018570
3. [3]Kinlin LM, Weinstein M. Scurvy: old disease, new lessons. Paediatrics and international child health, 2023.PMID 37795755