# Pleural effusion within 24 h of admission predicts severe hypertriglyceridemia-induced acute pancreatitis and organ failure: retrospective cohort of 296 patients

## TL;DR

Pleural effusion detected within 24 hours of admission helps predict severe hypertriglyceridemia-induced acute pancreatitis and organ failure.

## Contribution

Pleural effusion is shown as a novel early predictor for severe hypertriglyceridemia-induced acute pancreatitis and organ failure.

## Key findings

- Pleural effusion had the strongest correlation with severe hypertriglyceridemia-induced acute pancreatitis (OR: 6.82).
- Pleural effusion showed higher predictive accuracy than CRP for severe hypertriglyceridemia-induced acute pancreatitis.
- Pleural effusion is a practical early marker when composite scores or lab results are unavailable.

## Abstract

Early risk-stratification in hypertriglyceridemia-induced acute pancreatitis (HTG-AP) is challenging within the first 24 h of admission. We assessed whether pleural effusion (PE) detected on early imaging serves as an early predictor for the development of severe HTG-AP (HTG-SAP) and organ failure (OF), compared with BISAP, MCTSI, and C-reactive protein (CRP).

A retrospective study included 296 HTG-AP patients at Xuanwu Hospital from August 2013 to February 2024. PE presence within 24 h was abstracted from chest CT; outcomes were HTG-SAP and OF. Diagnostic performance was evaluated using ROC analysis and DeLong tests, comparing with BISAP, MCTSI, and CRP. The prognostic impact of PE laterality (unilateral vs. bilateral) was also analyzed.

PE demonstrated the strongest positive correlation with hypertriglyceridemia-induced severe acute pancreatitis (HTG-SAP) (OR: 6.82; 95% CI: 3.13–14.88; p < 0.001). PE achieved the area under the curve (AUC) of 0.792 (95% CI: 0.742–0.837) for HTG-SAP prediction and 0.718 (95% CI: 0.663–0.768) for OF anticipation. The predictive accuracy of PE was significantly higher than that of CRP for predicting HTG-SAP (ΔAUC = 0.106; p = 0.004) and comparable for predicting OF (ΔAUC = 0.055; p = 0.112). There was no significant difference between PE and MCTSI scores in predicting either HTG-SAP or OF. However, PE had a lower predictive accuracy compared with the BISAP for both HTG-SAP (ΔAUC = 0.057) and OF (ΔAUC = 0.083; p < 0.001). Despite this, PE still demonstrated substantial predictive value for HTG-SAP and OF. There was no significant difference between unilateral and bilateral pleural effusions in predicting the risk of developing HTG-SAP and OF.

PE detected within 24 h is a simple, readily available early radio-graphic marker that identifies patients at high risk for progressing to severe course and OF in HTG-AP. While not superior to BISAP, PE offers pragmatic utility when composite scores or complete laboratories are unavailable and may trigger early monitoring and escalation.