Bronhiolitis izazvan atipičnim bakterijama kod hospitalizovane dece

Ivane Chkhaidze1,Dali Zirakishvili2, Neli Barnabishvili3
1Tbilisi State Medical University, Tbilisi, Georgia
2Iashvili Central Children Hospital, Tbilisi, Georgia
3 “Test-Medical House” Diagnostic Centre, Tbilisi, Georgia

Summary

Introduction: Bronchiolitis is the most common reason for hospitalization worldwide. Respiratory syncytial virus (RSV), human Metapneumovirus, human Rhinoviruses, human Bocavirus have been shown to predominate. A few studies however have attempted to determine whether other pathogens, particularly Mycoplasma Pneumoniae (Mpn) and Chlamydophila pneumoniae (Cpn), are associated with bronchiolitis in children under 2 years of age. The aim of this study was to determine the prevalence and severity of Mpn and Cpn infection in children under the age of two years presenting to the Iashvili Central Children Hospital in Tbilisi.
Material and Methods: Acute and convalescent serum samples were tested by ELISA for IgM and IgG antibodies to RSV, Cpn and Mpn. 37 children under two years of age were studied. In 19 patients out of 37 (51.35%) etiological diagnosis were established and in 18 patients (48.65%) no pathogens were found. 11 patients (29.72%) had either Cpn or Mpn and 8 patients (21.62%) had RSV.
Results: Children infected with Cpn and Mpn had less severe bronchiolitis than those infected with RSV. There were no statistically significant differences between groups with respect to length of hospital stay.
Conclusion: Our study underlines the importance of atypical bacterial pathogens in acute bronchiolitis in children under two years of age and highlights the complex epidemiology and clinical features of these pathogens in this age group.

Key words: mycoplasma pneumoniae, chlamydophila pneumoniae, respiratory syncytial virus, bronchiolitis, children

Sažetak

Uvod: Bronhiolitis je najčešći uzrok hospitalizacije odojčadi i male dece širom sveta. Respiratory syncytial virus (RSV), humani Metapneumovirus, humani Rhinoviruses, humani Bocavirus smatraju se dominantnim uzročnicima. I drugi uzročnici, naročito Mycoplasma Pneumoniae (Mpn) i Chlamydophilapneumoniae (Cpn), udruženi su sa pojavom bronhiolitisa kod dece mlađe od dve godine života. Cilj našeg istraživanja je bio da odredimo učestalost i težinu bronhiolitisa izazvanih Mpn i Cpn kod dece mlađe od dve godine života, lečenih u Dečjoj bolnici Iashvili u Tbilisju u Gruzijii.
Metodologija: Akutni i rekovalescentni serum pacijenata testirani su ELISA testom na IgM i IgG antitela na RSV, Cpn and Mpn. 37 –oro dece mlađe od dve godine života je ispitivano. Kod 19-oro dece (51.35%) detektovan je uzročnik, dok kod 18-oro pacijenata (48.65%) uzročnik nije utvrđen. 11-oro pacijenata (29.72%) je imalo infekciju Cpn ili Mpn a osam pacijenata (21.62%) je imalo infekciju RSV.
Rezultati: Deca sa bronhiolitisom izazvanim Cpn i Mpn imali su manje ozbiljne forme bolesti u odnosu na decu kod kojih je izolovan RSV. Koinfekcija nije uticala na težinu bolesti u našoj studiji. Nije bilo statistički značajne razlike između grupa u odnosu na dužinu hospitalizacije.
Zaključak: Rezultati naše studije naglašavaju značaj atipičnih patogenih bakterija za pojavu bronhiolitisa kod dece mlađe od dve godine, i ističu kompleksnost epidemioloških i kliničkih karakteristika ovih patogenih uzročnika u grupi dece do dve godine starosti.

Ključne reči: mycoplasma pneumoniae, chlamydophila pneumoniae, respiratorni sincicijalni virus, bronchiolitis, deca

Introduction

Bronchiolitis is the most common reason for children hospitalization in many countries, challenging both economy, area and staffing in paediatric departments (1, 2).

The causes of bronchiolitis have been studied in different environments and populations. In most studies Respiratory syncytial virus (RSV), human Metapneumovirus, human Rhinoviruses, human Bocavirus have consistently been shown to predominate.
A few studies, however, have attempted to determine whether other, particularly atypical pathogens Mycoplasma Pneumoniae (Mpn)and Chlamydophilapneumoniae (Cpn), which are frequently detected in older children and adults with asthma exacerbation, are associated with bronchiolitis in children under 2 years of age (3,4,5).

Objectives

The aim of this study was to determine the prevalence and severity of atypical pathogens in children under the age of 2 years presenting to the Iashvili Central Children Hospital.

Materials and Methods

Acute and convalescent serum samples were tested by ELISA for IgM and IgG antibodies to RSV, Cpn and Mpn. Positive results were defined by a significant antibody response in specific IgM or a 4-fold increase in IgG titer in paired serum samples.

Severity of bronchiolitis 1
Table 1. Dyspnea Score

Children included in the study were divided into age groups of 0-6 months, 7-11 months, and 12-24 months.

Daily dyspnea score (Table 1) was assessed in all patients by using symptom score on a scale from 0 to 10 based on a clinical scoring system according to Kristj'ansson et al. (6).Children with dyspnea score from 0 to 3 were considered as a mild bronchiolitis, with score 4-6 as a moderate and with score 7-10 as a severe bronchiolitis.

The results have been analyzed by the SPSS Statistics versions 16.0. p<0.05 has been considered as significant difference.

Results

Thirty sevenchildren under two years of age were studied. Their median (range) age was 11.86 month (age distribution from 3 to 23 months).Etiological diagnosis was established in 19 patients out of 37 (51.35%).Patients were grouped according to pathogens in three groups: in the group I were included 11 patients with Cpn and Mpn; in the group II - 8 patients with RSV; in the group III – 7 patients with mixed-infections with Cpn, Mpn and RSV.
There was no significant difference in age between infants presenting with bronchiolitis associated with different pathogens.
Overall, 57.9% (n = 11) of children had milddisease, 31.6% (n=6) moderate disease and 10.5% (n=2) severe disease. Children with RSV were more likely to have moderate and severe than mild disease (62.5% vs.27.3%, p <0.05) compared to children without RSV infection, whilst children with Cpn and Mpn infection were more likely to have mildthan moderate disease (72.7% vs. 37.3%, p = 0.05).

Infants with RSV had higher bronchiolitis severity scores with a median of 4.89 vs. infants with atypical pathogens (median 3.37, p<0.05) and vs. infants with mixed-infections (median 3.57, p<0.05).

Conclusion

Our results showed that children infected with Cpn and Mpn had less severe bronchiolitis than those infected with RSV. Co-infection was not associated with the disease severity.

References

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