## 4 Discussion
qSOFA has been designed as a tool in predicting sepsis as an alternative to SIRS, which lacked specificity [14; 28]. Thus, it has been previously linked to intraabdominal sepsis [29], being considered an independent risk factor for severity and an indirect predictor for the length of stay in cases of acute cholangitis [30]. Persistent organ dysfunction is associated with severe PEP [7], and multiorgan dysfunction seems to be a relatively frequent finding in post-ERCP AEs [24]. In ERCP patients, qSOFA predicts severity of acute biliary pancreatitis and cholangitis [31], being considered the earliest predictor of sepsis in patients with acute cholangitis presenting for ERCP procedures [32]. So far, there are no data within the literature to show any correlation between qSOFA and the severity of PEP or any other post-ERCP AE. However, similar to our results, both SIRS and qSOFA seem to predict severity and mortality in all-cause pancreatitis irrespective of ERCP procedures [33; 34]. Post-ERCP AEs increase the overall length of hospital stay and in-hospital mortality rates to over 1% [35]. Nevertheless, both length of stay and in-hospital mortality have been linked to low caseloads and limited ERCP experience of specific centers [36]. However, despite the AEs, ERCP procedures have been shown to decrease overall mortality rates of referred patients [35]. Our results show no correlation and thus no predictive power of either SIRS or qSOFA over the length of hospital stay in PEP patients. This fact could be explained by the lack of locally implemented criteria for discharging patients, resulting in disparities regarding length of stay in patients regardless of admittance diagnosis. One potential alternative predictor for PEP severity is the CRP level. The CRP level has previously been correlated with not only PEP severity [37], but also with all-cause length of stay in patients with post-ERCP AEs [38]. However, it seems that CRP levels may be highly influenced by pre-ERCP conditions, such as acute cholangitis, acute biliary pancreatitis, or even uncomplicated bile duct obstructions, thus generating potential bias in interpreting their predictive value for post-ERCP PEP severity [39]. Other studied markers for PEP severity have predictive value, although it has not yet been clearly defined [39; 40]. Despite its prospective value, our study is limited by a number of factors that require attention. First, the cohort is comprised of patients referred to a tertiary emergency unit; thus, the severity and complexity of cases are predominantly high, resulting in higher rates of post-procedural complicated evolutions of patients. This calls into question how the observed parameters would predict severity of PEP in regular cases and in the absence of numerous comorbidities. Such comorbidities along with longstanding and complex bile duct obstructions could influence the predictive values of SIRS and qSOFA. Second, due to the lack of clearly established discharge criteria after post-ERCP AEs, length of hospital stay may have been biased, and thus, no predictive values of the studied parameters could be found. Moreover, the high rate of post-ERCP infections and the association between infectious AEs and PEP could have biased the true predictive potential of both SIRS and qSOFA when related solely to PEP. Subsequently, the lack of alternately studied scoring systems and biomarkers, such as those included in the revised Atlanta classification of acute pancreatitis, is among the most important limitations of our study, but their workup and follow-up in routine clinical practice is still challenging.