Delta Neutrophil Index as a New Marker of Purulent Inflammation in Men With Non-odontogenic Abscesses of the Neck

Introduction If non-odontogenic abscesses and phlegmons (all purulent inflammations where the etiology is not a diseased tooth) of the neck are not promptly treated, they can lead to serious complications and even end in the death of the affected patient. Classical markers of inflammation such as plasma concentration of leukocytes (WBC), neutrophils (Neu), C-reactive protein (CRP), and erythrocyte sedimentation rate (ESR) are elevated in inflammatory neck diseases, but none of them has been proven as a definite marker in the prediction of this type of pathology. This necessitates the search and analysis of new indicators that could be used in the diagnosis, follow-up, and prognosis of patients with purulent neck infections. Potentially, such a marker could be the delta neutrophil index (DNI), which is increasingly entering clinical practice as a prognostic indicator in critically ill patients with life-threatening illnesses, including sepsis and systemic inflammatory response syndrome (SIRS). In the world literature, there are no data that have been studied in patients with purulent diseases of the neck of non-odontogenic origin, which is the aim of this original article. Materials and methods This retrospective study included 40 men with an average age of 46 (18-87) years with non-odontogenic abscesses and phlegmons of the neck who were hospitalized and operated on. In all of them, the concentration of leukocytes, eosinophils (Eo), neutrophils, and mature polymorphonuclear neutrophil leukocytes (PMN) was examined on an automatic 5-Diff hematology analyzer, ADVIA 2120i (Siemens Medical Solutions USA, Malvern, PA). Thus, it was calculated according to the formula for calculating DNI (DNI% = (Neu%+Eo%) - PMN%). Retrospectively, 30 healthy men with an average age of 42 (18-81) years were used as a control group, in which the same indicators were examined during a preventive examination. Results and discussion Comparing the mean values of WBC, Neu, and DNI between the studied patients with non-odontogenic purulent neck infections (n=40) and the healthy male controls (n=30) it was found that all three indicators of inflammation are significantly higher in the ill men, and these differences are statistically significant (p<0.05): 10.19 ±2.68x103/L versus 7.37 ±1.93x103/L for leukocytes, 7.68 ±2, 76x103/L versus 4.13 ±1.48x103/L for neutrophils, and 1.11±0.83% versus -1.07±1.22% for DNI. Therefore, the high mean numbers of measured WBC and Neu in men with non-odontogenic purulent neck infections were associated with an increase in their mean calculated DNI. This gives us reason to think that while WBC and Neu alone are not sufficient for definitive diagnosis, treatment follow-up, and prediction of disease outcome, in combination with DNI they become reliable indicators in purulent neck infections. Conclusions The DNI correlates well with other well-known and established indicators of inflammation, such as the concentration of leukocytes and neutrophils in the peripheral blood of patients. Its calculation is fast as an implementation procedure and is economically beneficial. Its independent use in the diagnosis and treatment of these diseases is about to be investigated and analyzed.