Preventive and therapeutic effectiveness of bioflavonoids in children with recurrent respiratory infections

Мета роботи. Підвищення ефективності лікування та профілактики гострих рекурентних респіраторних інфекцій (ГРРІ) шляхом застосування сиропу Імунофлазід® у дітей молодшого шкільного віку. Матеріали і методи. Обстежено 50 дітей молодшого шкільного віку з ГРРІ. Ефективність застосування сиропу Імунофлазід® визначалась шляхом порівняння динаміки клінічних симптомів, особливостей мікрокристалізації слини, бактеріального складу фарингеального ексудату до дослідження та через рік проведення лікувально-профілактичних курсів. Висновки. Сироп Імунофлазід® при лікувально-профілактичному застосуванні сприяє покращанню загального стану здоров’я дітей, зменшенню проявів інтоксикаційного, астенічного синдромів, частоти та тяжкості перебігу гострих респіраторних інфекцій, кількості днів пропусків занять у школі, числа та тривалості госпіталізацій, нормалізації кристалоутворюючого потенціалу слини на тлі зменшення мікробіологічного навантаження ротової порожнини.


Introduction
Health status analysis of the child population of Ukraine proves the current tendency towards a constant increasing proportion of school-aged children with recurrent and long-term acute respiratory infections (ARI) [6,7].Children suffering from common conditions of the upper respiratory tractacute recurrent respiratory infections (ARRI)pose a special problem for paediatricians and general practitioners.They account for the majority of visits to paediatricians, disruptions in school attendance, and hospitalizations; they are administered a wide range of drugs, but the lack of efficient and timely preventive measures in this category of children results in chronic conditions in 70.0% of them, among which the leading place is occupied by the otolaryngologic and bronchopulmonary diseases [13].This group of children is very heterogeneous.It is necessary to distinguish those patients who have episodes of repeated viral infections, and children with chronic diseases of the ENT organs and respiratory tract, developmental anomalies of the respiratory tract, congenital or acquired immune dysfunctions, etc.
There is a fact to consider that the definition of "recurrent respiratory tract infections" (RRTI) today remains quite controversial, arbitrary and is too general in nature, with a lack of explicit medical consensus.For the RRTI diagnosis in children, we adhered to the recommendations of the Italian Society of Pediatric Allergy and Immunology with the detection of one of the following criteria [13]: -≥6 respiratory infections per year; -≥1 respiratory infection per month with the upper respiratory tract involvement from September to April; -≥3 respiratory infections per year with the lower respiratory tract involvement.
Data of currently conducted studies show that though the immune system of children with ARRI does not have rough primary and acquired defects, it is characterised by extreme intensity of the immune response system, intercellular cooperation violation and insufficiency of reserve capacity, which are the consequence of a long-term and massive antigenic exposure on the child's organism [9][10][11].
Our studies suggest that any serious abnormalities in the health status, immune or non-immune pathologies were not revealed in the majority of children with ARRI, which allowed to diagnose the physiological status of their respiratory system.This means that in certain cases these changes can be considered as an adaptive reaction of the child organism's response to the excessive load of infectious antigens, unfavourable environmental factors and socio-environmental challenges.A partial decrease in certain immunity indices, which was revealed in some children with ARRI, was temporary and de facto reflected an increased tendency to response against infectious agent, which can confirm its secondary, post-infectious nature.Nonspecific changes in immunity indices are a consequence of reinvasions of infectious agents, rather than favourable factor that leads to their development.According to our data, 83.3% of children with ARRI had latent and recurrent intracellular infections (herpes virus type 1 and type 2, Epstein-Barr virus, cytomegalovirus, chlamydia and mycoplasma), which significantly burdened the inflammatory process and reduced its treatment efficacy [6].
An issue of ARRI prevention and treatment during the formation period of organised school groups, which are rightfully classified as high-risk groups, is particularly topical, as far as they are notable for the cross infection due to their active transference and characterised by an increased incidence, which, in turn, may be an indirect proof of immune changes in this adaptation period [7].Flu vaccination is an efficient preventive measure; however, due to the serologic plasticity of the pathogen, the continuous monitoring and development of new vaccine strains circulating in the human population in each specific epidemic season are required.
In recent years, the properties of Imunoflazid ® syrup have investigated in experimental and clinical studies, the active ingredients of which are the bioflavonoids (BF) of such herbs as bushgrass (Calamagrostis epigeios L.) and tufted hair grass (Deschampsia caespitosa L.)the stable molecular complexes of aglycone flavonoid compounds, consisting of free aglycones (tricine, apigenin, luteolin, quercetin, rhamnazin), O-glycosides and C-glycosides [1, 2].The major characteristic of these bioflavonoids is the direct antiviral action due to their biological properties; in addition, they function in the human body as antioxidants [1, 2, 8].
It is proved that the antioxidative activity of BF of Imunoflazid ® syrup is achieved by inhibition of the activated oxygen metabolites (AOM) generation by cells of the macroorganism.The generation rate of superoxide anion radical after the 2-hour cell incubation with BF decreased by 20-30%, after the 4hour incubationby more than 50% reduction observed, and after the 24-hour incubation, the generation of AOM by the macroorganism's cells was almost completely inhibited [8].Flavonoids affect the antioxidant system: at the stage of free radical and peroxide formation, they act as traps for free radicals, suppress a number of enzymes, provoke an oxidative process and protect antioxidant enzymes from damage [16].
BFs potentiate the apoptosis inducers effect, activate initiation caspase-9 by intracellular mechanisms and contribute to the elimination of affected cells, thereby an apoptosis-modulating effect achieved, which is important for preventing the development of chronic processes associated with the latent viral infection persistence [8].
In recent years, the effect of BF on the cell receptors, including receptors stimulating detoxification processes, has been determined [17].Such properties are of paramount importance for children with ARRI, since persistent inflammatory processes, accompanied by increased proinflammatory cytokine production and the immune balance violation, lead to the chronic intoxication and a decrease in the adaptive properties of the organism [9].
For preventing polypragmasy in this category of children, efficient use of combined drugs that, except for specific antiviral action, should have a wide range of immunomodulating and general tonic properties, which results in search for new means of prevention and treatment of respiratory infections and determines the relevance of the study.

Objective.
To improve treatment and prevention efficacy of acute recurrent respiratory infections by using Imunoflazid ® syrup in the primary school-aged children.

Materials and methods
To perform the assigned tasks 50 children aged 7-10 years with recurrent respiratoty infections were examined, who suffered from ARIs during the academic year more than six times and had 35-40 days of absenteeism on average due to the disease during the academic year.The comprehensive examination and treatment in this group of children was agreed upon with their parents.
The followed-up children had no clinically significant organic respiratory and otolaryngologic diseases, congenital and acquired immune deficiencies.All children were followed-up for 12 months; they were administered prophylactic (anti-relapsing) treatment courses, which included Imunoflazid ® syrup at the age-related doses for three weeks twice per year (September-October and February-March).Additionally, in case of clinical symptoms of respiratory infection, this group of children was administered a 5-day treatment course with the indicated above drug (no more than twice per year).
The efficacy of Imunoflazid ® syrup was determined by comparing the dynamics of clinical symptoms during the year, the features of saliva microcrystallization (SMC), the bacterial composition of the pharyngeal exudate at the baseline and a year after the treatment and prevention courses.
The study of the crystallization function of mixed saliva was carried out according to P.A. Leus [4].Dried saliva drops were examined microscopically.Depending on the arrangement of crystals, three types of saliva microcrystallization were distinguished: -Type I of SMC is represented by a large centrally located arboraceous or crystal-like pictures ("fern"); the percentage of oral cavity and tonsils diseases in children with this type is no more than 12-15%; -Type II of SMCoccasional crystal-like conglomerates or needle-like crystals across the visual field of microscope; the percentage of oral cavity and tonsils diseases in children with this type does not exceed 25-30%; -Type III of SMCfragmented occasional fine crystals without a specific orientation (sometimes in the form of drops); this type is accompanied by multiple noncompensated inflammatory processes of the oropharynx.
The results of a comparative evaluation of the microcrystallization indices of three biological fluids (serum, oral fluid, urine) of experimental animals and humans prove that microcrystallization of saliva is a general index of the organism's homeostasis, which can be used to evaluate the efficacy of preventive, curative and rehabilitative measures, and predicting the disease course as well [3].A number of studies [5, 14] deals with the investigation of the saliva microcrystallization in various somatic pathologies.
Statistical processing of the study outcomes was carried out using Excel.The main characteristics are given as quantitative observations (n), arithmetic mean (M), standard error of mean (m), absolute and relative values(abs.,%), and statistical significance (p).Comparison of statistical characteristics in different groups and during follow-up care was carried out using parametric and non-parametric tests.When determining the statistical significance of differences between independent groups of study by comparison the mean values of the studied indices, unpaired t-test was used.

Results
The study outcomes showed that there was a decrease in signs of prolonged asthenic and intoxication syndromes, manifested in increased physical activity and performance efficiency in 25 (50.0%)children, fatigue reduction in 33 (66.0%) patients, increased sleep duration in 16 (32.0%)cases, improved appetite in 26 (52.0%) children (p≤0.05) after 12 months of the follow-up care.
Reduced number of ARVI episodes during the follow-up period compared to the previous year was recorded in 16 (32.0%)children, which is illustrative of a high efficiency of the preventive courses (Table 1).One or two episodes of respiratory disease were observed in 6 (12.0%) children.The follow-up care of these children showed that they had uncomplicated course of ARI, reduced duration and severity of the key symptoms that did not require any additional drug administration or inpatient treatment.In 42.0% of children, normalization of haemoglobin and WBC were observed, and the rheological parameters of blood improved.
In 13 (26.0%)children, the clinical efficiency of preventive therapy was found to be low.While analyzing the past medical history of this group of children, there were no specific features of the respiratory infection course concerning its severity, complications or

Table Table 1. Dynamic pattern of certain clinical and laboratory parameters in children with ARRI (n=50)
Clinical symptom Abs.severe concomitant conditions, but these were children from multi-member families with low socioeconomic status.

%
Children who were administered Imunoflazid ® syrup with prophylactic and treatment purpose throughout the year had a 3-fold decrease in the incidence of the herpes virus infection reactivation, a decrease in the hospitalization rate by 19.0% and its durationby 27.0%.
When estimating the number of days of the disruptions in school attendance, it was established that in the previous year this number was 37.5±3.7 days per year, and at the end of the follow-up period -21.2±1.5 days (p≤0.05).In addition to the above, the number of bed-days in case of hospitalization for the complicated ARI decreased from 14.8±1.3 to 8.1±1.9 days; p≤0.05 (Fig. 1).
A microbiological study of the oropharynx in 92.0% of children during the period with no clinical Before the use of Imunoflazid ® syrup ® syrup

Number of bed days
manifistations of the disease, the following pathogenic microorganisms and commensals were cultured: St. aureus -68.0 %, Str.haemolyticus -48.0 %, Str.pyogenes -52.0 %, or associations of coccal flora or their combination with Е. coli -18.0 %, C. albicans -34.0 % and P. aeruginosa -10.0 %.The persistence of potentially pathogenic bacteria in the oropharynx should be considered as an evidence of the local defence mechanisms exhaustion, which determines the risk of chronic processes formation associated with increased viral load.
During the follow-up control, the oropharynx microbiocenosis indices showed a great improvement after such preventive and treatment courses: the number of children with bacterial overgrowth and moderate growth of commensals and microbial associations was significantly reduced (the moderate and poor growth prevailed (grade III and II)), which was due to the immunological processes normalization associated with the antigenic viral load reduction; p<0.01 (table .2).
The type definition of the saliva microcrystallization, presented in Table 3, indicates that the type III of SMC was detected in 35.4% of children with ARRI, which indirectly evidenced a decrease in the mineralizing function, saliva pH, violation of its antioxidative properties and determined the decreased protective functions of the respiratory mucous membranes secondary to increased proliferative activity of potentially pathogenic flora.Moreover, the type I of SMC corresponded to the standard data, at the baseline of the observational study was found only in 6.3% of this cohort of children, and at the end of the yearin 39.6% of patients; p<0.01.

Figure 1 .
Figure 1.Number of days of the disruptions in school attendance and bed-days during the follow up care.