Журнал «Здоровье ребенка» 3 (46) 2013

Treatment of hematuric form of chronic glomerulonephritis (HFCGN) at children is an actual problem of children's nephrology because of insufficient therapy efficacy. One of the reasons of HFCGN torpid course is the presence of concomitant chronic Epstein-Barr viral infection. It is possible to assume, that treatment of Epstein-Barr viral infection (EBVI) will improve the course and prognosis of HFCGN.

The purpose of research was to define the efficacy of complex antiviral and immunotropic therapies at children with HFCGN and concomitant chronic EBVI.

 Materials and methods

54 children (27 girls and 27 boys) with HFCGN and chronic EBVI in the age from three till 17 years (on average 9,77±0,66 years) were observed. Duration of HFCGN has averaged 43,17±5,16 months. Diagnosis of HFCGN was formulated according to the standard classification of primary GN at children.

For diagnostics of chronic EBVI the following data was determined: antibodies of class IgM VCA, IgG EA, IgG VCA, IgG EBNA by method of immune-enzyme analysis (IEA) with use of diagnostic immune-enzyme system "Vector-Best" (Russia) on immune-enzyme analyzer ChemWell-291 and the virus antigen by method of polymerase chain reaction in blood, saliva, urine with use of detecting amplifier DT-96 NPO "DNA-technology". EBVI was considered as chronic active at revealing the DNA of EBV in the blood, increased level of IgM VCA, IgG ЕA, IgG EBNA [3, 11]. Stage of EBVI without reactivation was defined at absence of viral DNA in blood and revealing of increased IgG VCA, IgG EBNA. According to the above-stated criteria chronic active EBVI was established at 35 (64,8 %) children, chronic EBVI without reactivation - at 19 (35,2 %) children.

Nephrological examination was carried out with the use of general clinical and radioimmunological methods. General clinical methods included the blood and urine analysis, research of daily proteinuria. The intensity of hematuria was determined according to the general urine analysis and Nechiporenko test. In the general urine analysis hematuria was considered as insignificant when up to 10 erythrocytes in field of vision (fov) were found, as moderate - from 10 up to 60 in fov, as severe - from 60 in fov up to the whole field of vision. In the Nechiporenko test: minimal hematuria – the amount of erythrocytes not more than 10´10⁶ /l, moderate - from 10´10⁶/l up to 60´10⁶/l, severe - more than 60´10⁶/l. For the estimation of kidneys functional condition the concentration of urea and creatinine in blood serum was determined, glomerular filtration rate (GRF) according to the Schwarz's formula was counted, Zimnitskiy test was carried out. As the marker of kidney tubules damage the level of β₂-microglobulin was studied in urine by radioimmunological method with the use of immune-enzyme test system “β₂-microglobulin IFA-BEST” (close corporation “Vector-Best”, Russia) on the automatic analyzer “StatFax 303 Plus”.

The immunological examination included the definition of interferon-α and interferon-γ levels and the content of pro-inflammatory interleukins (IL-1ß and Il-6) in blood serum by method of IEA on the photometer-analyzer “Stat Fax 303 Plus” with the help of IEA test system of close corporation “Vector-Best”, (Russia).

The group of control was composed from 29 conditionally healthy children.

The patients were prescribed with combined antiviral and immunotropic therapy of chronic EBVI: medication of recombinant α-2β interferon (Viferon®) and medication containing flavonoids Deschampsia caespitosa L. and Calamagrostis epiquous L. (Proteflazid®). At presence of chronic EBVI activity signs patients were also prescribed with acyclovir. Viferon® was applied in the dosage of 150-500 thousand UA (depending on age) 2 times a day under the following scheme: daily 10 days, then within one week 3 times a week, then 4-6 weeks 2 times a week. Proteflazid® was used for three months according to the age dosages.

Acyclovir was prescribed in the age dosage within seven days with the subsequent transition to the supporting dosage for 20 days. Virological, nephrological and immunological examination was carried out among the patients before treatment and 3 months after the end of treatment, i.e. in 6 months after inclusion to research.

 Mathematical processing of the received results was done with the program “STATISTICA 6.5” [8]. Qualitative attributes were compared by means of Pearson χ² criterion and Fisher φ criterion (Fisher's angular transformation). Statistically significant was considered the difference p <0,05.

Results of researches and their discussion

After the finishing of complex antiviral and immunotropic therapies positive dynamics of the clinical characteristic of the examined patients was noted (tab. 1). First of all, the changes concerned the reduction in frequency or full absence of respiratory diseases. Frequent ARVI have been registered only at third of patients, while before the treatment they were noted at 2/3 of patients. After the treatment practically at all patients the mild pyrexia, intestinal syndrome, arthralgias were liquidated. Frequency of asthenic syndrome has decreased twice. At absence of dynamics of lymphadenopathy frequency clear positive dynamics in reduction of system lymphadenopathy occurrence was noted. Hepatomegaly and cardiopathy were observed significantly less often. The spleen enlargement was liquidated. While the frequency of tonsillitis and adenoiditis has not changed.

The analysis of dynamics of clinical symptoms at 35 patients with active chronic EBVI, who had acyclovir in their complex therapy additionally, was performed separately. At these patients the reduction of ARVI frequency (82,9±5,6 % vs 34,2±4,1 %, р <0,01), systemic lymphadenopathy (45,7±4,6 % vs 5,6±2,4 %, р <0,01), asthenic syndrome (28,6±4,6 % vs 11,4±2,5 %, р <0,05), mild pyrexia (17,1±3,1 % vs 5,6±2,4 %, р <0,05) was also noted. The performed therapy has led to liquidation of splenomegaly and to practical disappearance of arthralgias and intestinal syndrome.

The estimation of dynamics of peripheral blood parameters has revealed significant reduction of lymphocytosis (from 18,5±5,3 % up to 9,3±3,9 %, р <0,05) at the examined patients, and also the frequency of ESR increase was decreased twice (from 27,7±6,1 % up to 13±4,6 %, р <0,05). At chronic active EBVI the reduction of lymphocytosis (from 25,7±3,5 % up to 11,4±2,5 %, р <0,05) as well as monocytosis (from 22,9±3,4 % up to 14,2±3,3 %, р <0,05) was observed.

Positive clinical dynamics at the examined children after complex antiviral and immunotropic therapies was associated with change of virus activity markers of EBVI. Signs of chronic EBVI activity were present at 35 (64,8 %) children before treatment and were liquidated at 17 (31,5 %) patients after it. After treatment IgM VCA was not determined at any patient. The level of IgG VCA (р <0,05) has decreased, moreover the frequency of detection of high level IgG VCA (from 48,1±6,8 % up to 29,6±5,8 %, р <0,05) has went down. The frequency of IgG EA revealing (from 42,6±6,5 % up to 22,2±5,4 %, р <0,05) and also EBV DNA in blood (from 50,0±6,8 % up to 33,3±6,4 %, р <0,05) went down. DNA in urine in dynamics was defined significantly less often - only at 8 (14,9±4,8 %) patients, р <0,05. Frequency of EBV DNA detection in saliva has not changed.

Antiviral and immunotropic therapy has also appeared to be effective for the course of HFCGN. So, in dynamics the significant reduction in number of children who had severe hematuria was observed - from 63,0±6,6 % up to 35,2±6,4 % (р <0,05). Frequency of macrohematuria relapses has decreased twice (from 38,9±6,5 % up to 18,5 ±5,3 %, р <0,05). The number of patients who had proteinuria more than 1 g/l has considerably decreased (from 9,3±3,9 % up to 3,7±2,6 %, р <0,05). Positive dynamics of the urinary syndrome has also been noted at children with active chronic EBVI.

The functional condition of kidneys according to creatinine data in blood serum, counted GFR at children has not been impaired both before and after treatment. Studying of such a tubular marker as β2-microglobulin of urine has revealed the reduction of tubular disorders frequency (from 20,3±5,5 % up to 7,4±3,6 %, р <0,05). So, increase of β2-microglobulin level in urine has been registered at 9 (25,7 %) children with HFCGN and chronic active EBVI before treatment and only at 2 (5,6 %) patients after the end of therapy.

After the treatment positive dynamics of the interferon status of patients (tab. 2) was noted. Increase in 2,7 times of interferon-α level and in 3,6 times of interferon-γ level was observed. However, the given parameters remained considerably lower than these parameters in the control group.

Dynamics of interferon-α and interferon-γ levels during therapy was identical at children with active chronic EBVI and with EBVI without reactivation. However, only at children without reactivation the level of interferon-α after treatment did not differ from parameters of control group. It indicates the more persistent dysfunction of antiviral protection of the organism at children with chronic active EBVI.

At research of pro-inflammatory cytokines in 3 months after the end of complex therapy significant reduction in the level of both IL-1 and IL-6 was noted (tab. 2). At the same time their average parameters have not achieved the level of control group, with the only exception - concentration of IL-1 at children with chronic EBVI without reactivation, which had no differences from control group.

Thus, the received results indicate the positive dynamics after performed antiviral and immunotropic therapies in the course of HFCGN and concomitant chronic EBVI, and also of the cytokine status. However the persistent reduction in levels of interferon-α , interferon-γ and increase of pro-inflammatory interleukins level (IL-1, IL-6) dictate the need for the repeated courses of complex therapy.

Conclusions

1. The use of complex antiviral and immunotropic therapy at children with HFCGN and chronic EBVI leads to reduction of respiratory morbidity frequency, mild pyrexia, asthenic syndrome, systemic lymphadenopathy, hepatomegaly, intestinal syndrome, lymphocytosis, liquidates splenomegaly. Signs of chronic EBVI activity, which were present at 35 (64,8 %) children before treatment, were liquidated at 17 (31,5 %) patients.

2. Positive dynamics of HFCGN symptoms during antiviral and immunotropic therapies of chronic EBVI was shown by the reduction of macrohematuria relapses, intensity of hematuria and tubular disorders.

3. The prescription of complex antiviral and immunotropic therapies leads to the reduction of changes in the immune status, namely increase of interferon-α and interferon-γ levels and also decrease in concentration of "pro-inflammatory" cytokines IL-1 and IL-6.