Background Vitamin B12 (Vit B12) deficiency is a common condition, which can be manifested with non-specific clinical features or with neurological and/or haematological abnormalities in severe cases. In systemic sclerosis (SSc) gastrointestinal involvement (GI), nutritional status and medications may lead to Vit B12 deficiency.
Objectives We aimed to investigate the frequency of Vit B12 deficiency and its determinants in SSc patients.
Methods Sixty-two (90.3% female) SSc patients were enrolled in to the study. The nutritional status of patients was assessed with Malnutrition Universal Screening Tool (MUST). Serum Vitamin B12, homocysteine and Helicobacter Pylori Immunoglobulin G (H. Pylori IgG) levels were measured in all patients. Serum Vit B12 levels of patients were classified as; Low (<200 pg/ml), Borderline (200 - 300 pg/ml) and Normal (>300 pg/ml). Serum homocysteine levels of patients were classified as; Elevated (>9 μmol/L) and hyperhomocysteinemia (>15 μmol/L). H. Pylori IgG antibody level >5 U/ml considered as positive. Serum Vit B12 level <200 pg/ml or being on Vit B12 replacement therapy was considered as B12 deficiency.
Results The mean age of the patients was 50.2 (12.5) years and mean disease duration was 12.0 (7.5) years. Forty-four (71.0%) patients were limited and 18 (29.0%) patients had diffuse SSc. The mean serum Vit B12 level of the patients was 323.6±291.5 pg/ml. Seventeen (27.4%) patients had normal, 23 (37.1%) patients had borderline and 22 (35.5%) patients had low serum Vit B12 level. Forty-four (71.0%) patients were considered as Vit B12 deficient; 22 had serum Vit B12 level <200 pg/ml (4 of these patients were on vitamin B12 replacement therapy), 22 were already on Vit B12 replacement therapy and Vit B12 level ≥200 pg/ml. The mean homocysteine levels were higher in the group with Vit B12 <200 pg/ml as compared to other groups (p=0.005). In the group with Vit B12 level <200 pg/ml, 33.3% (7/21) of the patients had hyperhomocysteinemia and 76.2% (16/21) had 'elevated homocysteine levels (Table). Fifty-one (82.3%) patients had GIS involvement and 16 (25.8%) patients had medium-high risk MUST score. H. Pylori IgG antibody was positive in 40 (64.5%) patients. There were no statistically significant differences between the patients with and without Vit B12 deficiency regarding to age, mean disease duration, hemoglobin level, GI involvement, medium-high risk MUST score, H. Pylori IgG antibody positivity and other clinical features (p>0.05 for all).
Conclusions SSc patients are at risk for Vit B12 deficiency. Using homocysteine level seems to be unpractical for confirmation of Vit B12 deficiency in a complex disease such as SSc because its level is influenced by many factors. Patients with SSc should be closely monitored for Vit B12 deficiency and replacement therapy should be planned if necessary.
Disclosure of Interest None declared