IMMUNOLOGIC ASPECTS OF PHAGE THERAPY OF INFECTIONS RELATED TO MEDICAL CARE IN NEUROREANIMATION

Abstract

Aim. Evaluate the effect of anti-phage humoral immune response on effectiveness of phage therapy of infections related to medical care (IRMC). Materials and methods. 42 patients on extended mechanical ventilation (MV) in neuroreanimation, 1 time in 2014, 4 times in 2015 and 1 time in 2016 had received bacteriophage cocktail per os - 20 ml including 6 patients - additionally 3-5 times. Effectiveness of phage therapy was evaluated by seeding of IRMC strains from samples of endotracheal aspirate, blood, urine and feces of patients before and after treatment. Results. 87.5% of samples from the patients initially had gram-negative pathogens (Acinetobacter baumannii, Klebsiella pneumoniae, Pseudomonas aeruginosa). Effective sanation for the first episodes of phage therapy was confirmed in 54 - 62.5% of cases. Pharmacokinetic studies have indicated a systemic mechanism of action for enteral forms of bacteriophages. Repeated courses of phage therapy did not result in significant eradication of pathogens. Antiphage immunity after a single administration of the cocktail of bacteriophages with a certain strain composition was detected using ELISA by the presence of specific IgG titers in a range from 1/16 to 1/4096 (in patients not receiving the cocktail antibodies were not detected). Conclusion. Reduction of sanation effect of bacteriophage could be due to formation of anti-phage antibodies after a repeated course in the same patient. Changes of strain composition of phage cocktail of bacteriophages is necessary to preserve results of phage therapy.