Diagnostic utility of HFLC% and IG% for acute Pancreatitis-A retrospective Case-Control study.

OBJECTIVE

To evaluate the occurrence, development and outcome value of hyperfluorescent lymphocyte percentage (HFLC%) and immature granulocyte percentage (IG%) for acute pancreatitis (AP).

METHODS

The laboratory data collected from 1533 patients diagnosed with AP between August 2018 and August 2022 were retrospectively analyzed. The patients were classified into mild acute pancreatitis (MAP) and non-mild acute pancreatitis (Non-MAP) groups; non-MAP groups were additionally subgrouped based on HFLC% at day 7. White blood cells (WBC), HFLC%, and IG% were examined from day 1 (baseline) to day 14 post-admission using Sysmex XN Series Hematology Analyzers. C-reactive protein (CRP), serum amylase (AMY), and lipase (LPS) were detected by Beckman AU5800.

RESULTS

A total of 623 patients were finally included in the study [MAP group (n = 358) and Non-MAP group (n = 265)]. WBC, IG%, and CRP were higher in the Non-MAP group from day 1 to day 12 (all P<0.05). The HFLC% was not statistically significant from day 1 to day 6; yet, it increased on day 6 and 7 in the Non-MAP group. We divided patients in the Non-MAP group with complete data(101 patients) into HFLC% ≥ 2.9 %(31 patients) and HFLC% < 2.9 %(70 patients) according to the threshold of 7th day HFLC%. WBC, HFLC%, IG%, and CRP effectively predicted the progression of MAP to Non-MAP (all P < 0.001). HFLC% was the most obvious value, followed by CRP and IG%. Combined with HFLC%, IG%,CRP and WBC in day7, the ROC analysis showed that the area under ROC curve of the combined indicators was the largest (AUC = 0.912, P < 0.001) and had higher sensitivity and specificity than single-item assessment of AP outcomes(P < 0.05). HFLC% < 2.9 %, IG% > 1.7 %, CRP >28.66 mg/L, and WBC >9.24 × 109/L indicated the possibility of AP disease aggravation. Also, HFLC% <2.9 % was directly associated with infection, SIRS, APPACHII grade, and ICU admission (all P < 0.05). In non-MAP there was a significant negative correlation between HFLC% and APACHE-II score (rs = -0.312, P = 0.023).

CONCLUSION

HFLC% <2.9 % on 7th day was directly indicated more infection, systemic inflammatory response syndrome(SIRS), higher APPACH II grade and ICU admission. HFLC% may be an independent laboratory marker for prognosis in AP. Combining HFLC% with IG%, CRP, and WBC helps evaluate AP patients' disease development and outcome.