Background: It is well recognized that inflammatory bowel disease (IBD) patients are at risk of developing nonalcoholic fatty liver disease (NAFLD). Our aim was to assess the prevalence of fatty liver in IBD patients as quantified by controlled attenuation parameter (CAP), compared to conventional methods of detecting hepatic steatosis.
Methods: For this observational study, we prospectively evaluated all IBD patients presenting for a disease flare or follow-up visit in our clinic, during a 12 month period (Nov 1st 2015 – Oct 31st, 2016). Clinical characteristics and laboratory data were recorded. Hepatic steatosis was evaluated by abdominal ultrasound, hepatic steatosis index (HSI) and transient elastography with CAP (Fibroscan, Echosens, Paris). Significant steatosis (S≥1) was defined for a CAP value over 236 , and the cut-off of HSI for detecting NAFLD was set at ≥36 .
Results: Altogether 36 IBD patients (17 ulcerative colitis, UC and 19 Crohn's disease, CD), mean age 43±13 years, 52.8% female, were included in the analysis. All patients denied alcohol use of more than 20 g/day. No significant difference in the two groups (UC, CD) was seen regarding disease activity (remission/flare – 52.9/47.1% in the UC group, 47.4/51.6% in the CD group), BMI (23.7 and 23.4 respectively), mean hemoglobin values (13.38 and 13.48 g/dl, respectively) or inflammatory markers (ESR 18 and 19.9 mm/h, fibrinogen 523 and 520 mg/dl, respectively). UC patients had higher mean cholesterol values (197.4 vs. 175 mg/dl) and 2 of them were diabetic (compared to none in the CD group). Mean CAP was similar among the two groups – 222 for UC and 223 dB/m for CD, as well as mean HSI, with values of 35±6 and 34±5, respectively. Ultrasound and HIS both identified 8/36 (22.2%) patients with fatty liver, whereas CAP assessment detected 3 more patients (11/36, 30.5%) with significant steatosis (S≥1). NAFLD-IBD patients were more likely to have CD, history of resection, steroid use and longer disease duration – Table 1.
Conclusions: CAP outperformed conventional ultrasound and HSI in detecting fatty liver in IBD patients. This result needs to be explored in larger cohorts.
 Imajo K, Kessoku T, Honda Y, et al. (2016), Magnetic Resonance Imaging More Accurately Classifies Steatosis and Fibrosis in Patients With Nonalcoholic Fatty Liver Disease Than Transient Elastography, Gastroenterology, https://http://www.ncbi.nlm.nih.gov/pubmed/26677985
 Bessissow T, Le NH, Rollet K, et al. (2016), Incidence and predictors of nonalcoholic fatty liver disease by serum biomarkers in patients with inflammatory bowel disease, Inflamm Bowel Dis, https://http://www.ncbi.nlm.nih.gov/labs/articles/27379445/