Elevated serum homocysteine as a predictor for vitamin B₁₂ or folate deficiency

Abstract

Tissue deficiency of vitamin B12 and folate results in an increase in serum homocysteine (sHcy). We have measured sHcy in patients with reduced serum vitamin B12 and/or red cell folate (RCF) to determine its usefulness as a discriminant for the diagnostic interpretation of reduced vitamin levels. Of 3846 patients who had serum vitamin B12 and RCF assayed, 335 (9%) had reduced vitamin levels. Multivariate analysis showed a significant association between sHcy and serum creatinine (p = 0.0001), positive intrinsic factor (IF) antibody or neutrophil hypersegmentation (NHS) (p = 0.001), increased MCV (p = 0.014) and low RCF (p = 0.025) but no relationship with the level of serum vitamin B12 or haemoglobin. After censoring the patients with renal impairment (n = 54), the distribution of the remaining 72 patients with elevated sHcy was 37/151 (25%) with low serum vitamin B12 with or without low RCF and 35/130 (27%) with low RCF alone. sHcy correctly identified response to vitamin therapy in 33/35 (94%) patients who had adequate parameters to assess response. The positive predictive values of IF antibody/NHS, macrocytosis and/or low RCF for elevated sHcy were 100% and 34% respectively. Twenty‐four percent of patients with a low serum vitamin B12 and elevated sHcy had no abnormal haematologic parameters as determined by the routine laboratory staff. These data suggest that the usefulness of measuring sHcy in a routine diagnostic setting is limited and a careful review of the peripheral blood for macrocytosis and NHS plus determination of RCF may be a more cost‐effective process than sHcy assay in most instances to determine the presence of tissue deficiency.

Red blood cell metabolism under prolonged anaerobic storage

“…74 Anomalies to homocysteine fine-tuning are known to be related to oxidative stress 74 and deficiency B-group vitamins. 75 However, no substantial alteration of vitamin intake was observed (retinol -vitamin A, riboflavin -vitamin B2 -Fig. S2, ESI †).…”

Possible Modulation of Vascular Function Measures in Rheumatoid Arthritis by Homocysteine

“…All the patients in the current study were on B vitamin supplements. Therefore, given the importance of B vitamins for homocysteine metabolism, we think that adequate B vitamins might have promoted the conversion of homocysteine to cysteine or methionine [ 26 , 27 ] and thereby prevented homocysteine elevation in the patients of the current study.…”

Glyphosate, pathways to modern diseases III: Manganese, neurological diseases, and associated pathologies

“…Another extensive study on children with autism compared with controls found low serum tryptophan, high serum glutamate and homocysteine, and significantly reduced free sulfate, as well as high levels of oxidative stress markers,[ 1 ] all of which are consistent with these assertions. High serum homocysteine is one associated consequence of folate deficiency:[ 76 ] Folate is produced by Lactobacillus and Bifidobacteria from products of the shikimate pathway. [ 240 ]…”