metabolic disease vitamin B12 deficiency icd11.foundation:1366882206 UMLS:C0042847 hypocobalaminemia NCIT:C131684 HP:0100502 EFO:0000734 MONDO:0020696 ICD9:266.2 vitamin b12 deficiency MESH:D014806 SCTID:190634004 A disease characterized by low serum levels of vitamin B12, either inherited or acquired. cobalamin deficiency MEDGEN:21880 vitamin B deficiency obsolete_vitamin B12 deficiency