Журнал «Здоровье ребенка» 3 (46) 2013

Introduction 

Immune, nervous and endocrine system are being integrated responsible for keeping the constant of internal environment of fetus organism and newborn child in stress conditions and high antigenic difficulties in labors and postnatal period. Therefore, the immune system condition determine survival rate of a child and life quality, rehabilitation or invalidism stage [1, 2, 9].

Children, which were born in early terms, have features of internal and gained immunity and they make the risk group of inflectional diseases appearance [1, 12].

Interaction of organs and systems in conditions of healthy organism in premature children during the first year of life characterized with lability of regulation, debilitation and dissociation of adaptation mechanisms [5,11]. It is known that mobilization of congenital and gained immunity factors in children of the first age of life is subordinated to general adaptive features. But their characteristic at different pathological conditions in premature children remains unexplored [5].

Respiratory system diseases during long time period take the third place in structure of child population morbidity, with perinatal pathology and congenital anomalies which takes the first place [6, 10]. Statistical data show that there is 29% of the first year of life children among those, who hospitalized with non hospital pneumonia in Ukraine [6,7].

It is known that, delayed pneumonia in early aged children with recurrent diseases conditioned with numerous factors, among which the premature takes the main place [8].

Age dismaturity of specific and non specific immune protection within children’s first 5 years of life manifests with more mild inflectional diseases appearance, more severe its prognosis, higher risk of complication appearance and infection generalization complication [3]. Premature children due to dismaturity of immune system and insufficient transplacental transmission of antibodies from mother are being most defenseless to infection [4, 5].  

There is no enough data about features of adaptive reactions development in premature children of the first year of life with different inflectional diseases including pneumonia.

That is the reason of searching the new criteria, which determine the stage and character of immune answer in the first year of life children with not hospital pneumonia which were born earlier. The search is actual and foreground direction of further scientific studies in pediatrics.

The aim of study was evaluation of immunological volumes in children of the first year of life, born with very low body weight, with nonhospital pneumonia.

Materials and methods

For this aim realization, clinical – laboratory and instrumental examination was provided in 50 children of the ages from 1 month to 1 year, born with very low body weight. Examination took place on the base of Vinnitsa Regional Clinical Hospital. Examined children were divided as: the main group consisted of the 25 children of the first year of life which were born with very low body weight (VLBW) with gestation term 28 ±0,69 weeks. Children of the main group were on treatment in department for children of early ages and in reanimation department with diagnosed nonhospital pneumonia. Comparison group consisted of 25 children of the first age who born with very low body weight and gestation term less than 31 weeks. These children did not have acute pathology during first examination and were on ambulatory catamnestic observation in Vinnitsa Regional Child Clinical Hospital. Physical development of the yeare of life children, who were born prematurely were applicable to their corrected age. Control group consisted of 30 almost healthy children of the first year of life.  

In all children who took the place in study anamnesis data, evaluation of functional condition of all systems and organs were received. Clinical laboratory and X-ray examination of the yeared children with nonhospital pneumonia were provided according to pneumonia diagnostic and severity condition estimation criteria according to Command of Ministry of Health of Ukraine (MHU) №18 from 13.01.2005. About Protocols approval of children’s medical care by specialty «Child pulmonology» and by pneumonia severity index (XII Pediatric Congress «Actual problems in pediatrics» 12-14.10.2010, Kiev).

Immune system condition in children with nonhospital pneumonia examined at hospitalization to stationary treatment. Immunological examination was provided in allegro-immunological centre «Immunologist» in Vinnitsa (License of MHU № 539053 from 8.04.2010).

Estimation of population and subpopulation of immunocompetent cells (CD3, CD4, CD8, CD16, CD22) was done with indirect immunoflouriscence with «DIAM» (Moscow) monoclonal antibodies, immunoregulatory index (CD4/CD8) was calculated also. B-lymphocytes functional activity was calculated by standard serum class A, M, G immunoglobulines concentration in blood serum with immunofermental test system («Immunoglobulines A, M, G – IFA (immunofermental analysis)», «Granum»,Kharkov). Neutrophile phagocytary activity volumes were estimated with tests of spontaneous and stimulated phagocytosis with nitroblue tetrazolium and neutral latex parts (NBT-test) («DIAM», Russia).Volumes, which characterize phagosytosis activity (phagocytary number and phagocytary index) were calculated also. The circulated immune complex (CIC) level estimation was carried out with method of selective precipitation of antibodies – antigen complexes with 10,5% polyethylenglicol («DIAM», Russia). Reaction of leucocytes migration Inhibition with phytohemaglutinin (IFA with PHA).

Statistical estimation of received data was carried out with standard pockets of programs for personal PC Statistica 6.0.

Results, discussion

In majority of examined children of the main group respiratory syndrome dominated at hospitalization. In clinical picture of nonhospital pneumonia low productive cough observed in 18 (72%) children of the main group. Respiratory insufficiency of I-II stages was diagnosed in majority number of children (80%) of the first year of life with nonhospital pneumonia. For the majority number of children with VLBW (72%) with nonhospital pneumonia, except pneumonic status, intoxication sign was present also. The feature of nonhospital pneumonia in majority of children with VLBW (60%) was the absence of fever reaction.

Objective examination of respiratory system organs revealed reduction of percussion sound in 12 (48%) children of the first year of life, who were born with VLBW. In children of the main group locus-confluent pneumonia was revealed at X-ray examination. In all children of the main group weakened breath, crepitation and/or small bubbing sonorous rales, localized over the pathological process locus were revealed during auscultation.

In examined children nonhospital pneumonia with bilateral localization of pathological process and locally lung damaging (96%) was dominated. It is important to note that majority of children of the main group (80%) had pneumonia of the II and III stages of severity. In 5 (20%) of children nonhospital pneumonia characterized with IV stage if severity.

Secondary cardiomyopathy in 8 (32%) of children, subatelectasis, in 4 (16%), otitis in 2 (8%) and pyelonephtitis in 2 (8%) of children took important place among singes and complications of nonhospital pneumonia.

Concomitant pathology such as D-deficiency rickets (28%) and iron-deficiency anemia (40%) was revealed in children of the first year of life with nonhospital pneumonia at clinical and instrumental examination. Atopic dermatitis signs observed in 5 (20%) children, the signs of intestine dysbiosis were noted in 19 (76%) children. Congenital defects of development (congenital heart and kidney and urine system defects) were diagnosed in 4 (16%) children also.

We analyzed immunological observation data in children of the main and comparison group. In the children of the first year of life with nonhospital pneumonia who were born with VLBW, leucocytes level (8,65±1,6 g/l) was within normative limits (table 1).

There was a decreased level of T-lymphocytes (CD3) (41,0±1,58%), T-helpers (CD4) (21±2,94%) in the main group if the first year of life children who were born with VLBW in comparison with immunological data of comparison group (p<0,05). CD8 level was within reference volumes 20 ±1,91% in children of the main group what led to decreasing of CD4/CD8 (1,05±0,09). There was no difference between volumes of T-killers (CD16) levels in children of the main (13,25±1,25%) group, comparison group (15,2±1,3%) and control group (16,6±2,3%). We revealed significant decreasing of CD3, CD4, CD22 and CD4/CD8 in the main group of children in comparison with immunological results in children of control group (p<0,05).

The feature of humoral immunity in the first year of life children who were born with VLBW was the absence of immunoglobulin A (IgA) in 40 (80%) of examined children. Increasing of immunoglobulin M (IgM) (1,19±0,23 g/l) was distinctive feature for the main group children, taking into account their diagnosis, (p<0,05) (table 2). Immunoglobulin G level (IgG), phagocytary number and phagocytary index were within reference volumes, which were immanent for children of this age group.

The low level of spontaneous phagocytosis with nitroblue tetrazolium (NST) (0,5 ±0,1%) characterize that phagocytary feature of phagocytes in children of the main group was decreased in comparison with comparison group data. It is important to note that CIC level was within normative limits. We also revealed significant decreasing of volumes of IgM, spontaneous and stimulated phagocytosis with nitroblue tetrazolium (NST) in children of the main group in comparison with control group data (p<0,05).

Thus, volumes level decreasing of T-lymphocytes (CD3), helpers (CD4), natural T-killers (CD16), CD4/CD8 index, decreasing of functional phagocytes feature, absence of IgA (80%) proves about immunoregulation process defects and anti-infectious immunity decreasing in children of the first year of life who were born prematurely.

We also provided analysis of immunological volumes in examined children depending on the severity stage of nonhospital pneumonia. It is important to note that for children with pneumonia of IV stage of severity the tendency of CD4 (18,2±1,0%) decreasing was noted. In children with II (20±1,06%) and III (21±1,23%) stage of severity of nonhospital pneumonia we observed tendency of CD4 increasing. But these volumes were decreased in comparison with level of CD4 of comparison group of children (28±0,6%) and control group (48,6±1,72%) (p<0,05). So, received data show testify about immune dysfunction in children of the first year of life with VLBW.

According to literature data, the importance in immune system condition estimation has CD4/CD8 index in peripheral blood volume which the intensity of immune answer depends of [2, 8]. According to our research data in children with pneumonia of IV stage of severity the decreasing of immunoregulatiry index took place (0,9±0,01) due to CD4 activity decreasing with maintenance of CD8 activity. Thus, analysis of immunological data allowed to reveal dysfunction of T-cell part of immune system at nonhospital pneumonia with the IV stage of severity in children of the first year of life who were born prematurely.

Conclusions

1. Provided study shows that in children of the first year of life, who were born with VLBW nonhospital pneumonia characterizes with almost asymptomatic clinical picture of the disease, intoxication sign presence without fever and with the signs of respiratory insufficiency of I and II stages. Among signs and complications of nonhospital pneumonia in children of the first year of life, who were born prematurely, secondary cardiopathy (23%) and subathelectasis (16%) takes an important place.
2. Feature of cell immunity in children of the first year of life who were born with VLBW is noted: decreasing of T-lymphocytes level (CD3), T-helpers (CD4), CD4/CD8 index. It is important to note, that there was absence of IgA and decreasing of functional phagocytes activity.
3. Decreasing of immunological answer: decreasing of CD3, CD4 and CD4/CD8 index is characterized for children of the first year of life who were born with VLBW and with nonhospital pneumonia. It shows that there is dismaturity of immune system of not premature child and poor answer to bacterial colonization.