P288 Vitamin B12 deficiency in patients with ileal resection for Crohn's disease: Frequency and predictive factors
N. Ben Mustapha1, M. Bejaoui*1, M. Mahmoudi1, A. Laabidi1, M. Fekih2, M. Serghini1, L. Kallel1, M. Fekih1, J. Boubaker1, A. Filali1
1La Rabta Hospital, Department of Gastroenterology A, Tunis, Tunisia, 2La Rabta Hospital, Department of Biochemistry, Tunis, Tunisia
Vitamin B12 deficiency is involved in a broad range of hematological, neurological and mucocutaneous disorders. Absorption occurs at the terminal ileum. Patients with Crohn's disease (CD) in whom the terminal ileum (RTI) was removed may suffer from a deficiency in this vitamin.
The aim of the study was to determine the frequency of vitamin B12 deficiency and associated factors in patients followed for CD with RTI.
We collected prospectively sera from patients followed for CD in clinical remission with RTI from January to September 2014.
Patients in which the metabolism of vitamin B 12 is disturbed (total gastrectomy, pernicious anemia or chronic intake of proton pump inhibitors) were excluded.
We performed a descriptive and analytical study to determine the demographic, clinical, biological features of the study population and looking for independent predictive factors of vitamin B12 deficiency.
A total of 51 patients were included. The average age of patients at baseline was 35.56 years [16-77] with a sex ratio M / F= 1.04. Forty-three percent of patients were active smokers at the time of inclusion.
The average time frame between RTI and diagnosis of CD was 58.5 months [1-264] while that between RTI and inclusion was 69.5 months [5-300]. The mean extent of RTI was 39.48 cm [7-110], the mean remaining healthy small intestine was 356.6 cm.
The mean serum vitamin B12, hemoglobin and mean corpuscular volume were respectively 297.86 ng/l [34-501]; 12.4 g/dl [7.5-16.5] and 86.4 fl [61-105.2].Vitamine B12 deficiency was seen in 9 patients (17,6%).
Univariate analysis shows that vitamin B12 deficiency was associated with an age over 40 years at baseline (p=0.015), a folate deficiency (p=0.028), resection of more than 30 cm of the ileum (p<0.030) and a healthy remaining small intestine less than 3 m (p=0.041).In multivariate analysis, only ileal resection upper 30 cm (p=0.046) was found as an independent risk factor for vitamin B12 deficiency.
The mean serum vitamin B12 was significantly higher (312.6 ng/l) in the subgroup of patients who was included within 5 years from RTI [G1] compared with the subgroup of patients [G2] included more than 5 years after RTI (263.5 ng/l); p = 0.046.
The threshold limit for the appearance of a vitamin deficiency was 60.5 months.
Vitamin B12 deficiency was not correlated neither with endoscopic (p=0.606) nor with clinical recurrence (p=0.490).
Our work demonstrated that vitamin B12 deficiency in patients followed for CD with RTI was seen in 17% of patients. It is correlated with extent of ileal resection (>30 cm) and delay after resection (beyond 5 years) probably related to the depletion of liver stocks. These patients should be screened for replacement therapy.