Diagnostic Value of Immature-to-Total Neutrophils (I/T) Ratio in Sepsis

Anila Lika, Iris  Mone, Irena Korita, Alma  Barbullushi

Aim: To evaluate the diagnostic usefulness of immature-to-total neutrophils ratio in sepsis diagnosis, differentiating from the Systemic Inflammatory Response Syndrome (SIRS), and also to compare it with other established predictive markers of sepsis.

Methods: This study included 188 patients (67, or ≈36% females) admitted at the University Hospital Centre in Tirana, Albania. Participants were divided into three groups: sepsis, SIRS and local infection (without SIRS). For all patients there were measured WBC, total neutrophils, neutrophils to lymphocytes ratio, immature-to-total neutrophils ratio, C-reactive protein (CRP) and procalcitonin (PCT). CRP and PCT were used as comparative, well-established predictive markers of sepsis.

Results: Mean value of WBC in study groups were 19±7.5 cells/mm3 in sepsis, 16.6±6.6 cells/mm3 in SIRS group, and 18±6 mm3 in group with local infections. Absolute neutrophils had the following mean values: in sepsis 15.8±7.1 cells/mm3, in SIRS group 14±4.4 cells/mm3 and 17±6.2 cells/mm3 in local infections. Immature-to-total neutrophils ratio was higher in sepsis group 0.2±0.11, compared to 0.1±0.089 in SIRS group and 0.12±0.077 in the local infection group. Neutrophil-to-lymphocyte ratio (NLR) had a higher mean value of 16.8±20.4 in sepsis, 11.3±15.1 in SIRS and lower in local infection group (8.7±5.7). Similarly, mean PCT level was very high in sepsis 10.0±18.7ng/ ml, 0.3±0.2 in SIRS and 0.4±0.4 in participants with local infections. Furthermore, mean CRP level was considerably higher among patients with sepsis (149±100mg/l) than in those with SIRS (42.3±45.3 mg/l) and  participants with local infections (34.6±75.1mg/l). Analysis of variance (ANOVA) demonstrated a statistically significant difference in the mean levels by disease categories of study participants (sepsis, SIRS, local infections) for I/T neutrophils ratio (P<0.001), but for not for absolute neutrophils (P=0.175), WBC (P=0.097) or NLR (P=0.163). For PCT and CRP, there was evidence of a statistically significant difference between groups (P<0.001). Multiple comparisons according to Tukey HSD test demonstrated significant pairwise differences between the following disease categories: a higher mean level for PCT, CRP, I/T neutrophils ratio in patients with sepsis compared to SIRS (P<0.001) and those with local infections (P=0.04, P=0.37, P=0.07).

Conclusion: I/T neutrophils ratio seems a highly accurate marker in sepsis diagnosis and differentiating from SIRS. This marker can be obtained at no-added cost, and monitoring serial levels can predict sepsis early, allowing to initiate treatment early, optimize antibiotic use, and reduce overall mortality.

Keywords: I/T neutrophils ratio, NLR, Sepsis; SIRS, total neutrophils, WBC.

Conflict of interests: The authors report no conflicts of interest.

Financial disclosure: Not applicable.

DOI: 10.61034/JGPOH-2024-15