Neutrophil to lymphocyte ratio

Neutrophil to Lymphocyte Ratio (NLR) is a blood test used in medicine as a marker of systemic inflammation and immune response. It is calculated by dividing the number of neutrophils by the number of lymphocytes in a patient's blood sample.

Overview[edit | edit source]

The NLR is a simple, inexpensive, and readily available laboratory test that can provide valuable information about a patient's immune system status. It has been used in a variety of clinical settings, including oncology, cardiology, and infectious diseases.

Clinical Significance[edit | edit source]

An elevated NLR is associated with a worse prognosis in many conditions, including cancer, cardiovascular disease, and sepsis. It can also be elevated in conditions of systemic inflammation, such as rheumatoid arthritis and lupus. Conversely, a low NLR may indicate a strong immune response and a better prognosis.

Calculation[edit | edit source]

The NLR is calculated by dividing the absolute neutrophil count by the absolute lymphocyte count. Both of these values can be obtained from a routine complete blood count (CBC) with differential.

Limitations[edit | edit source]

While the NLR is a useful tool, it is not without limitations. It can be influenced by a variety of factors, including age, sex, and the presence of certain medications. Furthermore, it is a nonspecific marker of inflammation and should not be used in isolation to diagnose or monitor disease.