Intra peritoneal abdominal fat area measured from computed tomography is an independent factor of severe acute pancreatitis

Purpose: The purpose of this study was to search for a possible relationship between acute pancreatitis (AP) severity and visceral fat (VF) surface on contrast-enhanced computed tomography (CECT).

Material and method: A total of 112 patients with AP who underwent CECT within 2 to 3 days after the beginning of AP were included. There were 68 mean and 44 women, with a mean age of 56.3±21.6 (SD) years (range: 19-98 years). AP was regarded as mild for patients with an hospital stay up to 5 days and severe for those with an hospital stay greater than 5 days. VF surface was measured on CECT at the level of L4-L5 and of the umbilicus. Association between AP severity and VF surface, computed tomography severity index (CTSI), modified CTSI (mCTSI) and other variables were searched for using uni- and multivariate analysis.

Results: At univariate analysis, the VF surface at the level of L4 was greater in patients with severe AP (129.3±68.6 [SD] cm²; range: 21.8-355.8 cm²) than in patients with mild AP (100.1±68.4 [SD] cm²; range:13.2-333 cm²) (P=0.006). Similarly, the VF surface at the umbilicus was greater in patients with severe AP (161.1±76.1 [SD] cm²; range: 31.3-376.7cm²) than in those with mild AP (128.4±74.3cm2; range: 12.8-323.1cm2) (P=0.024). CTSI and mCTSI were also associated to AP severity. At multivariate analysis, only VF surface either measured at the umbilical or at the L4-L5 level was associated with AP severity (P=0.017 and 0.006, respectively).

Conclusion: VF surface at the level of L4-L5 on CECT is an independent factor of AP severity. VF surface at the level of L4-L5 on CECT is an independent factor of AP severity. These results are in line with recent data on the role of abdominal fat in the genesis of inflammatory response, which is associated with severe forms of AP.