neutrophil_lymphocyte_ratio: Neutrophil-Lymphocyte Ratio (NLR)

In cliot: Clinical Indices and Outcomes Tools

Neutrophil-Lymphocyte Ratio (NLR)

Description

Calculates the Neutrophil-Lymphocyte Ratio (NLR), a readily available biomarker of systemic inflammation and stress. It is used as a prognostic indicator in various conditions including sepsis, COVID-19, cardiovascular disease, and solid tumors. Elevated NLR is generally associated with worse outcomes.

Usage

neutrophil_lymphocyte_ratio(neutrophil_count, lymphocyte_count)

Arguments

neutrophil_count	Numeric. The absolute neutrophil count (ANC) or percentage of neutrophils.
lymphocyte_count	Numeric. The absolute lymphocyte count (ALC) or percentage of lymphocytes. Note: Inputs must use the same unit (absolute count or percentage) for the ratio to be valid.

Value

A list containing:

NLR	The calculated ratio (Neutrophils / Lymphocytes).
Interpretation	General clinical context regarding normal vs. elevated ranges.

References

Zahorec R. Ratio of neutrophil to lymphocyte counts–rapid and simple parameter of systemic inflammation and stress in critically ill. Bratisl Lek Listy. 2001;102(1):5-14. Liu Y, Du X, Chen J, et al. Neutrophil-to-lymphocyte ratio as an independent risk factor for mortality in hospitalized patients with COVID-19. J Infect. 2020;81(1):e6-e12. doi:10.1016/j.jinf.2020.04.002

Examples

# Example 1: Normal Range
# Neutrophils 4000, Lymphocytes 2000
# NLR = 2.0
neutrophil_lymphocyte_ratio(4000, 2000)

# Example 2: Elevated (Severe Infection/Stress)
# Neutrophils 8000, Lymphocytes 500
# NLR = 16.0
neutrophil_lymphocyte_ratio(8000, 500)

cliot documentation built on Dec. 1, 2025, 1:06 a.m.