Prognostic value of the neutrophil-to-lymphocyte ratio in critically ill patients with severe pneumonia

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Published Oct 11, 2026
https://doi.org/10.62438/tunismed.v104i09.6735
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Vol. 104 No. 09 (2026): Tunis Med Sept 2026

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Ines Sdiri
Medical Intensive Care Unit, Habib Thameur Hospital, Montfleury, Faculty of Medicine of Tunis, University of Tunis El Manar, 1007, Tunis, Tunisia
Ines Sedghiani
Medical Intensive Care Unit, Habib Thameur Hospital, Montfleury, Faculty of Medicine of Tunis, University of Tunis El Manar, 1007, Tunis, Tunisia
Amira Hmaidi
Medical Intensive Care Unit, Habib Thameur Hospital, Montfleury, Faculty of Medicine of Tunis, University of Tunis El Manar, 1007, Tunis, Tunisia
Wafa Homrani
Medical Intensive Care Unit, Habib Thameur Hospital, Montfleury, Faculty of Medicine of Tunis, University of Tunis El Manar, 1007, Tunis, Tunisia
Imen Klai
Medical Intensive Care Unit, Habib Thameur Hospital, Montfleury, Faculty of Medicine of Tunis, University of Tunis El Manar, 1007, Tunis, Tunisia
Imen Zaghdoudi
Medical Intensive Care Unit, Habib Thameur Hospital, Montfleury, Faculty of Medicine of Tunis, University of Tunis El Manar, 1007, Tunis, Tunisia
Ahmed Smiri
Medical Intensive Care Unit, Habib Thameur Hospital, Montfleury, Faculty of Medicine of Tunis, University of Tunis El Manar, 1007, Tunis, Tunisia
Yesmine Garbaa
Medical Intensive Care Unit, Habib Thameur Hospital, Montfleury, Faculty of Medicine of Tunis, University of Tunis El Manar, 1007, Tunis, Tunisia
Nebiha Borsali Falfoul
Medical Intensive Care Unit, Habib Thameur Hospital, Montfleury, Faculty of Medicine of Tunis, University of Tunis El Manar, 1007, Tunis, Tunisia

Abstract

Introduction : Community-acquired pneumonia (CAP) is one of the main reasons for admission to intensive care. Several studies have suggested the potential role of the neutrophil-to-lymphocyte ratio (NLR) in risk stratification and prognosis prediction in septic patients. Our objective was to evaluate the prognostic value of NLR on admission to intensive care in patients hospitalized for CAP.
Methods : We conducted a prospective, single-center, observational cohort study in the medical intensive care unit over a six-month period, from July 2024 to December 2024. We included patients over 18 years of age admitted to intensive care for CAP.
Results : We included 126 patients with a median age of 68 years and a gender ratio of 1.13. The main comorbidities were diabetes (48.8%), hypertension (47.6%), and dyslipidemia (41.2%). The APACHE II and SAPS II scores were 7.7 ± 4.4 and 24 ± 7.4 points, respectively. Invasive mechanical ventilation was indicated in 30 patients (23.8%). Thirty-one patients (24.6%) were in shock and 31 patients (24.6%) had ARDS. The mortality rate was 46% with a median length of stay of 5 days. The median NLR was 8.85. An NLR > 9 was associated with mortality (p < 10⁻³) with an AUC = 0.69, sensitivity = 62%, and specificity = 64%. It was associated with an increased risk of shock (p=0.03), acute respiratory distress syndrome (p=0.01) and acute renal failure (p=0.04).
Conclusion : NLR is a relevant biomarker that can determine the short-term prognosis in patients hospitalized for CAP.

Keywords:

Neutrophil, Lymphocyte, Ratio, ICU, Prognostic, Pneumonia

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