Defects of immune system function in immunocompromised children with congenital cleft lip and palate and recurrent respiratory infections
Introduction. Problem of comprehensive rehabilitation in children with congenital cleft lip and palate (CCLP) is actual, because this pathology has high frequency of occurrence and often has no possibility to conduct stage-by-stage surgical treatment in time in connection with the development of recurrent infections of the respiratory tract and oral cavity. The aim of the study was to identify the characteristics of the functioning of the immune system in immunocompromised children with CCLP compared to immunocompromised children without congenital malformations of the face with recurrent respiratory infections (10 or more episodes per year) and exacerbations of chronic diseases of the oropharynx and upper respiratory tract. Material and methods. 62 children of both sexes (aged 1-3 years) were monitored. 3 groups of children were formed. The 1<sup>st</sup> study group included 20 children (8 girls, 12 boys) with CCLP, suffering from recurrent acute viral infections of the respiratory tract, herpes-viral infection and different infection of oral cavity. All patients were at the stage of preparation for surgery to correct a soft palate defect. The study group 2 (without CCLP) included 22 children (11 girls and 11 boys) suffering from recurrent acute respiratory infections and herpes-viral infection. The comparison group consisted of 20 conditionally healthy children of the corresponding gender and age. A clinical, anamnestic and immunological study was conducted. The state of CD3+-, CD3+CD4+-, CD3<sup>+</sup>CD8<sup>+</sup>-T-lymphocytes subpopulations, CD3+CD4+/CD3+CD8+<sup>-</sup>, CD3<sup>-</sup>CD19+-B-lymphocytes, CD3<sup>-</sup>CD16+CD56+-natural killer cells (NK) was studied by flow cytometry. Serum IgA, IgM, and IgG levels were determined using ELISA. The phagocytic and microbicidal functions of neutrophilic granulocytes (NG), as well as their spontaneous and induced oxidase activity, were studied. Results. All patients in the 1<sup>st</sup> study group (with CCLP) were immunocompromised. All of them had clinical signs of immunocompromising: the frequency of recurrent acute respiratory viral infections, herpes-viral infections and oral infections were more than 10 times a year, they were complicated up to 6-8 times a year by bacterial infections, and therefore children received up to 6-8 courses of antibacterial therapy per year. It was revealed that children with CCLP have combined defects of immune system: deficiency of NK, reduced level of serum IgG and disorders of the NG system: neutropenia, deficiency of actively phagocytic cells, impaired production of reactive oxygen species. In study group 2 (children without CCLP), clinical signs of immunocompromising were also detected: the frequency of repeated acute respiratory viral and herpes-viral infections reached 10 or more times a year, and the frequency of bacterial complications was observed 2-3 times a year. Other disorders of the immune system were detected in this group of patients: the inability of the immune system to respond to infectious pathogens prevailed due to an inadequate response of innate and adaptive mechanisms of antimicrobial protection in combination with various defects in the functioning of the NG. Conclusion. Combined secondary immune system defects have been identified in immunocompromised children with CCLP. At the same time in immunocompromised children without CCLP we observed another change in the immune system: the defective response of antimicrobial immune defense mechanisms - an inadequate immune response to infectious pathogens in combination with various disorders of the functioning of NG. The obtained data justify the need to develop new immunotherapy approaches aimed at correcting the detected defects in the functioning of the immune system in children with CCLP.