Dual-score framework: National Early Warning Score 2 and quick Sequential Organ Failure Assessment scores in acute pyelonephritis

Abstract

BACKGROUND

Acute pyelonephritis (APN) is a significant part of the healthcare burden globally. Early risk stratification in APN is crucial to guide intensive care unit (ICU) admission and anticipate in-hospital mortality. The relevance of scoring tools like quick Sequential Organ Failure Assessment (qSOFA) and National Early Warning Score 2 (NEWS2) in urology-specific infections has been unclear. Our study is among the first to prospectively compare the qSOFA and NEWS2 scores exclusively in non-emphysematous APN, a real-world cohort previously overlooked in research.

AIM

To assess the accuracy of NEWS2 and qSOFA scores in predicting ICU admission, in-hospital mortality and their role in guiding urological interventions among adults with APN.

METHODS

A prospective observational study, conducted at a tertiary care centre in South India over two years, on adult patients diagnosed clinically and radiologically with APN. Comprehensive clinical, laboratory, and imaging parameters were recorded. The cohort was stratified into patients requiring ICU and not requiring ICU to assess differences across parameters. The discriminative power of the NEWS2 and qSOFA scores for predicting expedited care and mortality was analyzed.

RESULTS

The NEWS2 score ≥ 5 emerged as a robust tool, identifying nearly all patients requiring ICU admission [sensitivity, 98.1%; area under the receiver operating characteristic curve (AUC): 0.977; P < 0.05] and predicting intervention with high accuracy (AUC-0.823; P < 0.05). However, the qSOFA ≥ 2 score proved to be the silent sentinel of mortality (AUC-0.839; P < 0.05), outperforming the NEWS2 score in prognostication. Interestingly, patients who later required ICU care had elevated NEWS2 scores at baseline, suggesting the missed early red flags. To the best of our knowledge, this is the first and largest prospective study to compare NEWS2 and qSOFA scores exclusively in non-obstructive, non-emphysematous APN.

CONCLUSION

In APN, NEWS2 (≥ 5) proved to be a pragmatic trigger for ICU triage, while qSOFA (≥ 2) better flagged in-hospital mortality. Together, they form a complementary framework as a simple, objective, and lifesaving bedside tool.

Keywords: Acute pyelonephritis; Triage; Intervention; In-hospital mortality; Quick Sequential Organ Failure Assessment; National Early Warning Score 2; Early warning scores

Core Tip: Acute pyelonephritis (APN) is common in urology, but existing studies on early warning scores often mix heterogeneous sepsis cohorts or emphasize stone-related or emphysematous pyelonephritis. Our prospective study is the first to focus exclusively on non-obstructive, non-emphysematous APN, a group frequently overlooked yet clinically challenging. We demonstrate that the National Early Warning Score 2 score reliably identifies patients who require intensive care unit care or urgent intervention, while the quick Sequential Organ Failure Assessment score more accurately predicts mortality. Used together, they provide a complementary dual-score framework for bedside triage and prognostication. This simple approach offers urologists and nephrologists a practical, objective tool to enhance decision-making and improve patient outcomes.