ICD-11 classes
03 Diseases of the blood or blood-forming organs
Anaemias or other erythrocyte disorders
Nutritional or metabolic anaemias
3A01 — Megaloblastic anaemia due to vitamin B12 deficiency

ICD-11 3A01 — Megaloblastic anaemia due to vitamin B12 deficiency

A disease caused by inadequate dietary intake of vitamin B12, impaired absorption of vitamin B12, surgical removal of the small bowel, coeliac disease or inherited mutations affecting absorption of vitamin B12. This disease is characterised by decreased levels of vitamin B12 in the body presenting with or without anaemia. This disease may present with fatigue, pallor, dizziness, seizures, or symptoms of dementia. Confirmation is by identification of decreased levels of vitamin B12 in a blood sample.

The diagnosis includes nothing.

The diagnosis excludes nothing.

Diagnosis with code 3A01 contains 8 clarifying diagnoses:

1. 3A01.0 — Hereditary Vitamin B12 deficiency anaemia
2. 3A01.1 — Neonatal vitamin B12 deficiency anaemia
3. 3A01.2 — Vitamin B12 deficiency anaemia due to low intake
4. 3A01.3 — Vitamin B12 deficiency anaemia due to intrinsic factor deficiency
   It contains 2 clarifying diagnoses.
5. 3A01.4 — Vitamin B12 deficiency anaemia due to intestinal disease
6. 3A01.5 — Drug-induced vitamin B12 deficiency anaemia
7. 3A01.Y — Other specified megaloblastic anaemia due to vitamin B12 deficiency
8. 3A01.Z — Megaloblastic anaemia due to vitamin B12 deficiency, unspecified