Clinical significances of neutrophil-to-lymphocyte ratio, platelet-to-lymphocyte ratio and lymphocyte-to-monocyte ratio in infectious spondylodiscitis

Abstract

Background: The changes in the rate of leukocytes are simple, rapid and hopeful inflammation parameters in many diseases. Despite the close relationship between spondylodiscitis and inflammation, the roles of leukocyte subtypes in spondylodiscitis have not been previously investigated.

Objective: To evaluate the value of neutrophil-to-lymphocyte ratio, platelet-to-lymphocyte ratio and lymphocyte-to-monocyte ratio in predicting abscess and etiology in spondylodiscitis.

Materials and methods: A total of 121 medical records of patients were analyzed retrospectively. The data were obtained from hospital records. The neutrophil-to-lymphocyte, platelet-to-lymphocyte and lymphocyte-to-monocyte ratios were calculated using neutrophil, lymphocyte, monocyte and platelet levels in complete blood count measurements. Patients’ clinical data, and their neutrophil-to-lymphocyte, platelet-to-lymphocyte and lymphocyte-to-monocyte ratio values, were analyzed statistically.

Results: A total of 121 medical records were evaluated; the male-to-female ratio was 1:1.2 and mean age was 56.1±16.6 years at the time of diagnosis. The lymphocyte-to-monocyte ratio was lower in patients with abscesses than patients with no abscesses (p=0.040). The ‘area under the curve’ value for lymphocyte-to-monocyte ratio was 0.626, with a cut-off point of ≤3.7 in predicting abscess in patients with spondylodiscitis. The mean neutrophil-to-lymphocyte ratio was higher and lymphocyte-to-monocyte ratio was lower in pyogenic spondylodiscitis compared to granulomatous spondylodiscitis (p=0.001 and p=0.038). The ‘area under the curve’ values for the neutrophil-to-lymphocyte ratio and the lymphocyte-to-monocyte ratio were 0.717 and 0.680, respectively, with cut-off points of ≥4.9 and <2.7, respectively, in discriminating pyogenic spondylodiscitis from granulomatous spondylodiscitis.

Conclusions: The neutrophil-to-lymphocyte ratio and lymphocyte-to-monocyte ratio are simple, broadly available and cost-effective parameters, and may be useful in the differential diagnosis of infectious spondylodiscitis. [Ethiop. J. Health Dev. 2020; 34(2):144-121]

Key words: Lymphocyte, monocyte, neutrophil, platelet, spondylodiscitis