Oral Treatment of Pernicious Anaemia: First Fifty Cases

Subnormal vitamin B12 concentrations and anaemia in older people: a systematic review

“…Although we did not find an association between subnormal vitamin B12 concentrations and anaemia in older people, this does not imply that patients with pernicious anaemia or age-related food-vitamin B12 malabsorption (with tissue depletion of vitamin B12 and very low vitamin B12 concentrations) will not benefit from vitamin B12 administration, especially since non-placebo-controlled studies showed (large) increases in haemoglobin concentrations or haematocrit after intramuscular or oral vitamin B12 administration in patients with pernicious anaemia or age-related food-vitamin B12 malabsorption [ 55 - 59 ]. However, apart from the undisputed reality of pernicious anaemia, the clinical impact of a subnormal vitamin B12 level in older people is unclear, especially since several observational studies and randomized controlled trials also showed no effect of vitamin B12 administration on cognitive function [ 60 - 62 ].…”

The effect of vitamin B12 and folic acid supplementation on routine haematological parameters in older people: an individual participant data meta-analysis

“…Guidelines recommend vitamin B12 supplementation in patients with very low serum vitamin B12 concentrations due to lack of intrinsic factor (IF) (pernicious anaemia) or food-vitamin B12 malabsorption. Several studies have shown significant increases in haemoglobin after vitamin B12 administration in these patients [14][15][16]. Thus, when low levels of vitamin B12 and folate are found, patients are often treated with injections or oral supplements [9,11,17].…”

Absorption of vitamin B12from the intestine

“…Most people accept that intrinsic factor is essential for the normal absorption of the vitamin, though some deny this (Mooney & Heathcote, 1966). The nature and function of intrinsic factor remain uncertain.…”