Exudative and productive types of inflammatory tissue response in newly diagnosed infiltrative pulmonary tuberculosis and factors determining them

Introduction. In the context of a steady decline in the tuberculosis morbidity and mortality, the need to improve the effectiveness of treatment of newly diagnosed patients is of particular importance, which is ensured not only by a rational choice of standard anti-tuberculosis chemotherapy regimens, but also by the appropriate use of pharmaceutical adjuvants. Aim. Evaluation of the features of NET-forming (NETs – neutrophil extracellular traps) function of neutrophils in patients with newly diagnosed infiltrative pulmonary tuberculosis in exudative and productive types of inflammatory tissue response. Materials and methods. The randomized prospective study included 180 patients aged 18–59 years with newly diagnosed infiltrative pulmonary tuberculosis divided into two groups: group 1 – 120 patients whose pathological process characteristics corresponded to the exudative type of inflammatory tissue response; group 2 – 60 patients with a process characterized predominantly by the productive type of inflammatory tissue response. The NET-forming ability of neutrophils was evaluated according to the author’s method of D.G. Novikov and colleagues, therefore, the content of citrullinated histone H3 was determined in peripheral blood serum samples. Results. Patients with the exudative type of inflammatory tissue response had more active bacterial shedding (34.8% higher), the growth of Mycobacterium tuberculosis culture was faster (less than 30 days) and more massive (+++) than in productive tissue reaction. The ability of peripheral blood leukocytes to form сloud-like NETs in the exudative type of inflammatory tissue response was 8.5 times higher than in the productive type; thread-like NETs formed 10% more often, which was accompanied by a high content of citrullinated histone H3 in the blood serum of patients. Conclusion. The revealed peculiarities of NET-formation in the exudative type of inflammatory tissue response are essential, and can serve as an additional diagnostic criterion of activity and severity of inflammation in pulmonary tuberculosis, which should be considered when developing prognosis models – variants (favorable, unfavorable) of the course of pulmonary tuberculosis and substantiation of indications for adjuvant therapy and choice of its regimen(s).