3A01.4

ICD-11 MMS 2026-01

Vitamin B12 deficiency anaemia due to intestinal disease

Description

A number of intestinal disorders can also cause vitamin B12 (cobalamin) deficiency. These include severe pancreatic diseases and small bowel diseases such as malabsorption, ileal disease (including tuberculous ileitis, lymphoma, amyloid, long-term survivors of pelvic irradiation), extensive small bowel resection or bypass, gastric surgery/reconstruction for obesity (bariatric surgery) and Crohn's disease. When jejunal blind loops are present, bacterial overgrowth within the loops competes for cobalamin, leading to cobalamin deficiency. Although not as common currently, infestation with the fish tapeworm, Diphyllobothrium latum, was once a classic cause of cobalamin deficiency.

Index terms

  • Vitamin B12 deficiency anaemia due to intestinal disease
  • Acquired megaloblastic anaemia due to vitamin B12 deficiency secondary to intestinal disease

Exclusions from above levels

  • 04 – Diseases of the immune system
  • 05 – Endocrine, nutritional or metabolic diseases
  • 18 – Complications of pregnancy, childbirth or the puerperium
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  • 19 – Certain conditions originating in the perinatal period
  • 20 – Congenital malformations, deformations or chromosomal abnormalities
  • 22 – Injury, poisoning or certain other consequences of external causes
  • http://id.who.int/icd/entity/1000704511 – Human immunodeficiency virus disease
  • JB64.1 – Other diseases of the blood or blood-forming organs or certain disorders involving the immune mechanism complicating pregnancy, childbirth or the puerperium

Sibling codes

  • 3A01.0 – Hereditary vitamin B12 deficiency anaemia
  • 3A01.1 – Neonatal vitamin B12 deficiency anaemia
  • 3A01.2 – Vitamin B12 deficiency anaemia due to low intake
  • 3A01.3 – Vitamin B12 deficiency anaemia due to intrinsic factor deficiency
  • 3A01.5 – Drug-induced vitamin B12 deficiency anaemia
  • 3A01.Y – Other specified megaloblastic anaemia due to vitamin B12 deficiency
  • 3A01.Z – Megaloblastic anaemia due to vitamin B12 deficiency, unspecified

Foundation entity

Vitamin B12 deficiency anaemia due to intestinal disease – http://id.who.int/icd/entity/1470734867

Allowed postcoordination axes

Part of: 3A01: Megaloblastic anaemia due to vitamin B12 deficiency › 03: Diseases of the blood or blood-forming organs