Neutrophil-Lymphocyte Ratio in Predicting Infective Endocarditis: A Case-Control Retrospective Study

Abstract

Background. Infective endocarditis (IE) is a complex infectious disease with high morbidity and mortality. The inflammation mechanism of IE is a complex network including interactions of inflammatory cytokines and other components of host response. As an important inflammation marker, the prediction ability of neutrophil-to-lymphocyte ratio (NLR) in IE deserves further investigation. Methods. NLR values were measured and compared between IE patients and healthy controls, good and bad clinical outcome groups. The receiver operating characteristic curves (ROCs) of NLR and cut-off values were measured in IE patients, pathogen-subgroups, and different clinical outcome groups. Results. There were 678 IE patients and 2520 healthy controls enrolled in our study. The number of good and bad clinical outcome patients was 537 and 141, respectively. The value of NLR was significantly higher in IE patients than healthy controls ( 6.29 ± 9.36 vs. 1.87 ± 0.34 , p < 0.001 ), and the area under the ROC (AUC) was 0.817 (95% CI (0.794, 0.839), p < 0.001 ). The critical value of NLR for diagnosis of IE was 2.68, with a sensitivity of 69%, and a specificity of 88%. The value of NLR was significantly higher in bad clinical outcome patients than in good clinical outcome patients ( 5.8 ± 6.02 vs. 3.62 ± 2.61 , p < 0.001 ). The critical value of NLR to predict the outcome of IE was 5.557, with a sensitivity of 39.0% and a specificity of 85.3%. Conclusions. NLR is a predictive marker for IE patients, especially in Gram-negative bacteria and Gram-positive bacteria-infected IE patients. NLR also can predict the outcome of IE. Early detecting NLR upon admission may assist in early diagnosis and risk stratification of patients with IE.

Prognostic Value of a Novel Parameter in Patients with Infective Endocarditis

“…In recent times, investigators have made a great effort to explore factors to judge the prognosis of patients with different diseases, such as IE [ 8 – 12 ]. LDH, lymphocyte, and LWR are inexpensive, easy to get, and automated factors that timely and effectively forecast the prognosis of the patients with different sicknesses [ 13 – 17 ]. Previous researches suggested that the performance (accuracy/precision) of the combination of LDH and lymphocyte (LDH/lymphocyte) was better than that of LDH and lymphocyte alone [ 5 ].…”

Neutrophil–lymphocyte ratio in acute ischemic stroke: Immunopathology, management, and prognosis

“…Patients with infective endocarditis have similarly higher stroke risk, 60 and are also thought to have higher baseline NLR due to the inflammatory nature of this condition. Higher baseline NLR is predictive for in‐hospital outcomes, 61 and may have a role in the risk stratification of patients 61 . However, a literature gap exists with NLR use in AIS patients with underlying infective endocarditis, with, to our knowledge, no studies in this group of patients, despite the higher stroke risk which infective endocarditis confers 60 …”

Prognostic Value of Lymphocyte-to-White Blood Cell Ratio for In-Hospital Mortality in Infective Endocarditis Patients

“…Inflammatory factors, derived from lymphocyte, including platelet-to-lymphocyte ratio (PLR), neutrophil-to-lymphocyte ratio (NLR), and LWR, are eagerly connected with the clinical results of patients [ 17 ]. Some studies suggested that lymphocyte and its related index, such as platelet-to-lymphocyte ratio (PLR) and neutrophil-lymphocyte ratio (NLR), were associated with the diagnosis and prognosis of IE [ 11 , 12 ]. Our work also found that lymphocyte count was lower in the nonsurvivor group compared with the survivor group, while it was not significant.…”

“…However, a sole index could not truly reflect all possible conditions of patients. Recently, some studies tried to analyze the value of comprehensive indexes, such as lymphocyte and its related index in predicting prognosis of IE [ 11 , 12 ], while the association of lymphocyte-to-white blood cell ratio (LWR) with short-term mortality in IE patients remains unknown. Therefore, we conducted this investigation to evaluate the value of admission LWR for prediction of short-term mortality in IE patients.…”