Home › Biomarkers › Neutrophil/lymphocyte ratio
One study followed 90 patients in intensive care. With planned bowel surgery, the share of neutrophils rose from 62.5% before the operation to 84.4% after it. The share of lymphocytes fell from 28.1% to 10.3%.[1]
On this page, you can read what the neutrophil/lymphocyte ratio is, what the guidelines say about a value that is too low or too high, what affects your value and which values are best to look at alongside it.
Also known as: NLR, neutrophil-to-lymphocyte ratio, neutrophil-lymphocyte stress factor. At the lab: n/a.
The neutrophil/lymphocyte ratio is the number of neutrophils divided by the number of lymphocytes. Both are white blood cells. The ratio can be worked out from the absolute counts or from each type's share of all white blood cells.[1]
Neutrophils and lymphocytes respond differently when the body is under heavy strain. In the study, the share of neutrophils rose and the share of lymphocytes fell. The ratio sums up those two movements in one number.[1]
Doctors in intensive care have long been looking for a value that is easy to measure and shows how heavily stress or inflammation is weighing on the body. The ratio comes from an ordinary white blood cell count.[1]
In the study, how severe the course of illness was went together with how far neutrophils and lymphocytes moved apart. The author therefore proposes the ratio as a measure of severity, under the name neutrophil-lymphocyte stress factor.[1]
According to the author, the ratio can be measured in intensive care every 6 to 12 and 24 hours. Whether the ratio also says something about how things will go from there is something further research still has to show.[1]
| What the study found | What it can indicate | Who it is for |
|---|---|---|
| Neutrophils from 62.5% to 84.4%, lymphocytes from 28.1% to 10.3%[1] | Can point to the immune system's normal response to the stress of surgery | Patients having planned bowel surgery |
| 83.2% neutrophils and 9.5% lymphocytes even before surgery, then 89.9% and 7%[1] | Can point to a severe inflammation in the abdomen | Patients having emergency abdominal surgery |
| Neutrophils up to 94%, lymphocytes around 3.8%[1] | Can point to a very severe inflammation throughout the body and a severe course of illness | Critically ill patients in intensive care |
Source: Zahorec, 2001. A study of 90 patients in intensive care. The figures are shares of all white blood cells, not ratios. The source gives no limits for healthy people.[1]
A high ratio means a lot of neutrophils compared with lymphocytes. In the study, this could point to the immune system's response to surgery, to inflammation throughout the body or to a more severe course of illness. The study looked at critically ill patients in intensive care, not at healthy people.[1]
BioProfile is working on its own zones for each value, from risk to optimal. A doctor reviews those zones before they appear in your result.
After planned surgery in the study, the share of neutrophils rose and the share of lymphocytes fell. From the day after the operation, neutrophils slowly fell and lymphocytes rose again.[1]
In the study, a severe inflammation in the abdomen or throughout the body went together with many neutrophils and few lymphocytes, sometimes even before surgery.[1]
The mix of white blood cells changes quickly. The study measured on the day before surgery, on the day itself and on the two days after. So a value mainly tells you something about that moment.[1]
The neutrophil/lymphocyte ratio is in all five packages, from BioProfile 31 to BioProfile 150.[2]
The BioProfile editorial team wrote this page on 22 October 2026 from the sources below, which we read on 22 October 2026. Every number on this page comes from one of those sources, with that source's number next to it. An expert is still reviewing this page; after that review, the expert's name and the date of the review will appear at the top. This page explains and does not diagnose. Discuss an abnormal value with your GP.
