P546 Diagnostic value of laboratory tests in the assessment of malnutrition in patients with ulcerative colitis

Clinical: Therapy and observation Variables analyzed: demographic data, Montreal classification, concomitant medications, smoking, perianal CD, presence of LOE and duration of CD at initiation of therapy. LOE was defined as one of the following: need for steroids, occurrence of major abdominal surgery during treatment, dose increase, interval shortening or switching of the anti-TNF agent. Patients were allocated in three subgroups regarding DD: <24 months, between 24 and 60 months and >60 months. Our hypothesis was that DD did not influence the rates of LOE in these specific subgroups. The influence of DD on LOE rates was analyzed with Fischer and chi-square tests (p < 0.05). Results: A total of 175 patients were included in the study (117 under IFX and 58 under ADA therapy). The groups were considered homogeneous. Medium follow-up period was 17.3 (±12.4) months on the IFX and 13.1 (±11.3) months on the ADA group. Overall, LOE occurred in 47/117 (40.2%) of the IFX and in 9/58 (15.5%) ADA patients (p = 0.001). The average disease duration was 40.2 months in the IFX group and 60.3 in the ADA patients (p = 0.130). LOE occurred in 32% of patients with DD <24 months, in 33.3% with DD between 24 and 60 months and in 31.3% of subjects with DD over 60 months (p = 0.975). The distribution of the patients in these subgroups did not differ regarding the agent administered, IFX or ADA (p = 0.455). Conclusions: Loss of efficacy (LOE) was observed in 40.2% of the IFX and in 15.5% of the ADA patients. Disease duration (DD) did not influence LOE rates. These results suggest that patients with early CD might have the same rates of LOE than patients with long lasting disease. Controlled studies are needed to better address this issue. P546 Diagnostic value of laboratory tests in the assessment of malnutrition in patients with ulcerative colitis M. Sanges1 *, M. Miniero1 , M.G. Ceriello1 , A. Piacente1 , L. Florio1 , D. Trio1 , O. Donatore1 , D. Mattera1 , R. Sollazzo1 , A. D’Arienzo1 . 1 Federico II University of Naples, Gastroenterology Unit, Department of Clinical and Experimental Medicine, Naples, Italy Background: Nutritional care is important in the management of patients with ulcerative colitis (UC) and early recognition of malnutrition is central in these patients. There are several laboratory tests for the nutritional assessment of UC patients, but the gold standard has not yet been established. Our aim was to evaluate the diagnostic performance of laboratory tests in identifying malnutrition in UC. Methods: 137 UC patients were enrolled. For the anthropometric assessment, the following variables were evaluated: weight, height, body mass index (BMI), triceps skinfold thickness (TSF) and mid-arm muscle circumference (MAMC). Patients with malnutrition were defined as those with BMI < 18.5 kg/m2 or unintentional weight loss >10% in the last six months and TSF or MAMC <15th percentile. Using the anthropometric criteria as the gold standard, we evaluated the diagnostic performance in identifying malnutrition of the following laboratory tests: lymphocyte count, total proteins, albumin, prealbumin, transferrin, total cholesterol, creatinine and creatinine height index (CHI). Results: 81 (59.1%) patients were in active phase and 56 (40.9%) were in remission. According to anthropometric criteria, 32 (23.4%) patients were malnourished. The prevalence of malnutrition was significantly higher in patients with active UC (37%) than in patients in remission (3.6%) (p < 0.001). The diagnostic performance of laboratory tests is given in the table. Creatinine, total cholesterol and CHI showed the best diagnostic performance. Cut-off values were 0.6 mg/dL for creatinine, 129 mg/dL for total cholesterol and 89% for CHI. Conclusions: Our data have shown that creatinine, total cholesterol and CHI are useful markers for the diagnosis of

S229 malnutrition in UC. On the other hand, widely used nutritional parameters, such as albumin, prealbumin and transferrin, failed to be accurate markers of malnutrition in our patients. That is probably because serum levels of these proteins decease in response to inflammation and in UC decreased values may reflect acute disease rather than malnutrition. Table: Diagnostic performance of various laboratory tests in identifying malnutrition in patients with ulcerative colitis Albumin Prealbumin Serum Total Creatinine Transferrin Total CHI total cholesterol lymphocyte proteins count Sensitivity (%) 77 Specificity (%) 56 Accuracy (%) 62

79 60 64

76 51 59

83 86 84

80 88 84

68 65 64

79 52 62

89 93 90

CHI: creatinine height index.

P547 Diagnostic radiation exposure in patients with Crohn’s disease treated with infliximab H.-L. Ching1 *, F. Chariah1 , G. Lipman1 , M. Train2 , S. Mann1 . 1 Barnet and Chase Farm Hospitals NHS Trust, Gastroenterology, London, United Kingdom, 2 Barnet and Chase Farm Hospitals NHS Trust, Radiology, London, United Kingdom Background: Exposure to radiation from diagnostic imaging is thought to be associated with an increase in cancer risk. Patients with Crohn’s Disease (CD) frequently require x-ray exposure throughout the course of their illness. Studies have quantified cumulative radiation exposure in patients with CD [1]. However, as far as we know, there has only been one study that has identified infliximab as an independent risk factor for increased radiation exposure [2]. We aimed to quantify all imaging and associated radiation exposure for this subset of patients in our institution. Methods: Our unit is in a district hospital serving a population of 500,000. All patients with CD who have received infliximab from January 1997-August 2012 were identified from our hospital database. Diagnostic imaging records were also retrieved from the database. Using local protocols, a mean effective dose for each imaging modality was calculated. The cumulative effective dose (CED) per patient was calculated as the sum of the mean effective dose for all imaging modalities. The mean diagnostic radiation exposure per year = CED/years of follow-up. Results: 108 patients (57% female, mean age 43 years) were included in the study. Total number of imaging procedures was 414 (plain abdominal film = 236, CT abdomen/pelvis = 118, barium study = 60). Other imaging modalities included MRI abdomen/pelvis = 53 and abdominal ultrasound = 30. Average total number of imaging per patient was 4 (plain abdominal film = 2, CT abdomen/pelvis = 1, barium study = 1). The total CED for all imaging was 1271.8 mSv (85% attributed to CT imaging). The mean CED per patient was 11.9 mSv (range 0 171.9 mSv) with the mean diagnostic radiation exposure per year being 2.5 mSv/year (range 0 28.7 mSv/year). Conclusions: Imaging requests in patients with CD is high, particularly when they have received infliximab. In spite of concerns about radiation risk, 95% of our patients have CED less than 50 mSv exposure, a level considered to be associated with a low cancer risk. However, most patients are young and are likely to accumulate more radiation exposure over time. The move towards more specialised care should lead to reduction in use of CT scans and increased use of MRI and ultrasound studies. Reference(s) [1] Peloquin JM, et al. Diagnostic ionizing radiation exposure in a population-based cohort of patients with inflammatory bowel disease. Am J Gastro 2008;103:2015 22