Objective To investigate the early dynamic changes of biomarkers associated with capillary leak syndrome (CLS) in patients with severe acute pancreatitis (SAP) and their correlation with multiple organ failure (MOF).

Methods A total of 171 SAP patients admitted to the West China Centre of Excellence for Pancreatitis, West China Hospital, Sichuan University between September 1, 2019 and December 31, 2020 were enrolled for this study. The patients were divided into MOF and non-MOF groups based on the occurrence of MOF in the first 5 days of hospitalization, and were further divided into subgroups based on the presence of moderate-to-severe intra-abdominal hypertension (IAH). We performed dynamic monitoring of the blood biomarkers (hematocrit HCT, blood urea nitrogen BUN, and creatinine Cr), plasma proteins (albumin Alb, total protein TP, and non-albumin plasma proteins NAPP), and intra-abdominal pressure. Trends in these indicators across groups were analyzed comprehensively.

Results No significant differences in baseline data between the two groups were observed. The baseline data of the 2 groups were comparable. The MOF group had significantly higher rates of persistent systemic inflammatory response syndrome (SIRS) lasting 48 hours (91.3% vs. 71.8%), ICU admission (70.4% vs. 17.6%), and length-of-stay (32 ± 17.7 days vs. 19.0 ± 12.2 days) compared to those of the non-MOF group (P < 0.05). The incidences of respiratory, circulatory, and renal failures were higher in the MOF group than those in the non-MOF group, showing significant differences in circulatory failure (69% vs. 3.5%) and renal failure (65.5% vs. 3.5%) (P < 0.05). In the first 5 days of hospitalization, the MOF group showed significantly elevated BUN and Cr levels, while Alb and TP levels dropped rapidly upon admission and then gradually recovered. The NAPP level of the MOF group continued to decrease after admission, and on the third day after admission, the NAPP level was lower than that of the Non-MOF group, showing statistically significant difference (P < 0.001). The Alb/NAPP ratio of the MOF group decreased significantly on day 1 and then rapidly increased, showing significant differences between the groups on days 3 and 4 (P = 0.001). Subgroup analysis of MOF patients with moderate-to-severe IAH revealed similar trends in the dynamic changes and the overall changes in the indicators, and the difference was even more pronounced. The mixed linear model showed that the average levels of HCT, BUN, Alb/NAPP, and Alb/TP were higher and increased over time in the MOF combined with IAP subgroup (P < 0.001).

Conclusion The CLS model of SAP patients is validated, confirming that CLS is a key factor in the progression from SIRS to MOF. The loss of NAPP is an early and important indicator of CLS persistence and progression to MOF. Additionally, moderate-to-severe IAH accelerates the deterioration of MOF. These findings provide valuable insights into the potential mechanisms of MOF and warrant further validation through large-scale prospective studies.