Efficiency of combined postoperative treatment including an immunomodulatory Hexapeptide in children with acute destructive pneumonia

Acute destructive pneumonia (ADP) is a severe purulent and septic infectious disorder of childhood, characterized by a high level of morbidity and associated with imbalance of the immune system (IS). Hence, there is an obvious need to study the immunopathogenesis of this disease in order to develop new therapeutic strategy aimed at eliminating the pathogen, detoxifying the body, relieving respiratory failure and correcting functional immune deficiency. Our aim was to perform a clinical and immunological study in order to evaluate efficiency of immunomodulatory therapy using a medical drug with hexapeptide as an active substance. This drug was included into the complex postoperative treatment of children with acute destructive pneumonia. Clinical and immunological examination of 15 children 2-5 years old with ADP was performed before (study group 1 – SG1) and after (study group 1a – SG1a) combined postsurgical treatment including immunomodulatory therapy with a Hexapeptide-based pharmaceutical (HP, Arginyl-alpha-Aspartyl-Lysyl-Valyl-Tyrosyl-Arginine). Comparison group (CG) included twenty healthy children. The contents of T and B lymphocytes, natural killer cells (NK) were measured by means of flow cytometry (CYTOMICS FC 500, USA). Serum levels of IgA, IgM, IgG (ELISA), phagocytic and microbicidal activity of neutrophil granulocytes (NG) were also evaluated. Prior to the treatment in SG1 patients, a decreased number of CD3⁺CD19^-T lymphocytes, CD3⁺CD8⁺ T_CTL lymphocytes was revealed along with significant decrease in the contents of CD3^-CD16⁺CD56⁺ NK (p_1-3 < 0.05). It was found that in children with ADP, the IgG level did not differ from indices of control group, with a decrease of IgM (p_{1, 2} > 0.05), and increased level of IgA (p < 0.05). We have also found a deficiency of NG effector functions, i.e., insufficiency of active phagocytic NG with impaired capture and killing of bacterial antigen. Assays of NADPH-oxidase activity showed lacking response to both inflammation and additional induction by S. aureus. After complex treatment including immunomodulatory therapy in the SG1a group, we revealed a recovery in CD3⁺CD19^-T lymphocyte contents, CD3⁺CD8⁺T_CTL lymphocytes, CD3^-CD16⁺CD56⁺ NK (p_1-3 < 0.05). The trends towards normalization of IgA, IgM, improved NG effector functions (killing ability) were revealed due to activation of NADPH-oxidases. The restoration of immunological parameters in ADP was associated with earlier recovery from the purulent-destructive process in lungs, absence of postoperative complications including the prevention of septic process. The clinical and immunological effects of the immunomodulatory therapy program with HP-based pharmaceutical preparations suggest its potential usage during postoperative period in immunocompromised children with ADP.