Original article Arch Argent Pediatr 2018;116(3):192-197 / 192 Most commonly isolated viruses in asthma exacerbation and their correlation with eosinophil and total serum immunoglobulin E levels Mireya Robledo Aceves. Doctor of Sciencea. Alejandro Barrón Balderas. M.D.a and María de L. Jaime Ornelas. M.D.b ABSTRACT INTRODUCTION Background. Asthma exacerbations are still Asthma exacerbations are still one a cause of hospitalization at the Emergency Department. The triggers of asthma exacerbations of the main causes of hospitalization include allergens and infections –mostly viral–. in the Emergency Department. They The objective of this study was to establish the are triggered by allergen sensitization, relationship between viruses detected during an infections, and genetic factors.1,2 asthma exacerbation and eosinophil and serum immunoglobulin E (IgE) levels in pediatric Viral infections are one of the agents patients. involved in an already allergen- Population and methods. Cross-sectional. sensitized inflammatory process; analytical study. Children aged 5-15 years seen some authors suggest that recurrent at the Pediatric Emergency Department with an asthma exacerbation in the period between infections during early childhood March 2013 and February 2016 were included. are the cause of such frequent Viral ribonucleic acid was extracted from exacerbations, together with poorly- nasopharyngeal aspirates using the CLART controlled asthma and the resulting Pneumo Vir kit. Eosinophil levels were measured 3,4 in peripheral blood and total IgE levels, in serum. hospitalizations. Eosinophilia was defined as a count ≥ 0.4 x 103/ Rhinovirus is the most commonly mm3 and high IgE. as a level ≥ 350 IU/L. The isolated virus in people who Pearson’s correlation was carried out. A value develop asthma exacerbations, both of p ≤ 0.05 was considered significant. 5-7 Results. Out of 211 children with asthma children and adults. Most children 8 exacerbation, a virus was isolated in 20%. The with asthma have atopy. Gaining most commonly isolated viruses were rhinovirus. understanding of the relationship enterovirus, and respiratory syncytial virus. between specific viral infections and A correlation of 0.89 was established between eosinophil and total serum IgE levels in children allergic sensitization in asthmatic with asthma exacerbation and rhinovirus, with children will probably help to create a p value of 0.0001. strategies aimed at preventing Conclusions. Rhinovirus, enterovirus, and exacerbations. respiratory syncytial virus were the most a. Pediatric Emergency common viruses in asthma exacerbations in The objective of this study was Department. children younger than 15 years. A correlation to establish the relationship between b. Department of was established between eosinophil and IgE viruses detected during an asthma Pediatrics. levels in the presence of rhinovirus. exacerbation and eosinophil and Hospital Civil de Key words: rhinovirus, asthma, eosinophils, Guadalajara immunoglobulin E. serum immunoglobulin E (IgE) levels Dr. Juan I. Menchaca. in pediatric patients. Jalisco. Mexico. http://dx.doi.org/10.5546/aap.2018.eng.192 POPULATION AND METHODS E-mail address: Mireya Robledo The study was conducted at the Aceves: Doctor of To cite: Robledo Aceves M. Barrón Balderas A. Pediatric Emergency Department of Science: myreace@ Jaime Ornelas ML. Most commonly isolated viruses Hospital Civil de Guadalajara Dr. Juan yahoo.es in asthma exacerbation and their correlation with I. Menchaca, Jalisco, Mexico. This was eosinophil and total serum immunoglobulin E levels. Funding: Arch Argent Pediatr 2018;116(3):192-197. a cross-sectional, analytical study. None The study population was made up of children hospitalized due to an Conflict of interest: asthma exacerbation between March None. 2013 and February 2016. The study Received: 4-26-2017 group consisted of children with Accepted: 10-12-2017 asthma exacerbation aged 5-15 years. Most commonly isolated viruses in asthma exacerbation and their correlation with eosinophil and total serum immunoglobulin E levels / 193 An asthma exacerbation was diagnosed based RESULTS on the clinical presentation of sudden wheezing, Sample characteristics cough, dyspnea, polypnea, accessory muscle use, Out of 211 children with asthma exacerbation, radiographic findings of air trapping, history of 120 were boys (56.9%) and 43.1%, girls, and their prior wheezing in more than two occasions in average age was 97.8 months (range: 60-180 1 year, and nocturnal symptoms.1,9 All children months). Ninety-seven children were hospitalized who met the criteria for asthma exacerbation had between September and November (46%) and 42 a viral panel; those with asthma exacerbation (20%) had a positive viral panel with isolation of who had pneumonia or suspected bacterial one or more viruses (Table 1). infection were excluded from the panel. Only children with asthma exacerbation and a positive Isolated viruses viral panel had their eosinophil level measured Rhinovirus was the most commonly isolated in peripheral blood and total IgE measured in virus, in 26.9% (14 cases), followed by enterovirus, serum. Blood eosinophils were measured using in 19.2% (10 cases), RSV type B was isolated in a flow cytometry. Eosinophilia was defined as 9.6% (5 cases); RSV type A and bocavirus, in an eosinophil level > 0.4 x 103/mm3. Total serum 7.6% (4 cases); parainfluenza 3, adenovirus, and IgE levels were measured using an immunoassay, H3N2 influenza, in 5.7% (3 cases); influenza type IgE was considered high if it was > 350 IU/L. B, metapneumovirus B, and parainfluenza 1, in Inclusion criteria: All children with asthma 4% (1 case). Two viruses were isolated in the viral exacerbations who attended the Emergency panel of 10 children with asthma exacerbation Department for the first time were assessed (23.8%). Rhinovirus was the most common virus and those with a positive panel for one or more found in association with another virus: 2 cases viruses were included. also had RSV A, and 1 case each also had RSV B, enterovirus, parainfluenza 3, parainfluenza 1, and Virus detection metapneumovirus, H3N2 influenza and RSV B Virus samples were collected from the were isolated in 1 case; influenza B and bocavirus, nasopharynx through the nostril by inserting in 1 case; and RSV A and B, in 1 case (Table 2). a disposable suction catheter connected to an Children with a positive viral panel were extractor. Viral ribonucleic acid (RNA) was stratified into asthma exacerbation caused by extracted from the nasopharyngeal aspirate using rhinovirus, asthma exacerbation caused by the CLART PneumoVir kit by amplification of enterovirus, and asthma exacerbation caused by specific fragments from the virus genome and other virus (Table 3). The average age of children using a specific probe hybridization for each in the three groups was similar, between 84 virus. Detected viruses included adenovirus, and 113 months. A mild prevalence of male metapneumovirus A and B, parainfluenza 1, 2, 3, sex was observed among children with asthma and 4, respiratory syncytial virus (RSV) A and B, exacerbations and isolated viruses, but it was not bocavirus, coronavirus, H1N1 influenza, H3N2 statistically significant. In the rhinovirus group, influenza, influenza B and C, rhinovirus, and 57.1% were boys; in the enterovirus group, 88.9%; enterovirus. and in the other virus group, 63.2%. Statistics For the statistical analysis, quantitative outcome measures were described as mean TABLE 1. Characteristics of children with asthma ± standard deviation and range. Qualitative exacerbation outcome measures were expressed as percentage. Characteristic n= 211 The Pearson’s correlation was used to measure Age (months) (average ± SD [range]) 97.8 ± 41.3 (60-180) the correlation between eosinophil and total IgE levels in serum. A value of p < 0.05 was Sex (female/male [%]) 91/120 (43.1/56.9) considered significant. This study was approved Season (n/%) March through May (spring) 38 (18) by the Ethics and Research Committee of Hospital June through August (summer) 34 (16) Civil de Guadalajara; parents’ written consent September through November (fall) 97 (46) was obtained. The IBM SPSS Statistics software, December through February (winter) 42 (20) version 21, and Microsoft Excel, version 14.4.5. Positive viral panel (n/%) 42 (20) were used. SD: standard deviation. 194 / Arch Argent Pediatr 2018;116(3):192-197 / Original article Eosinophil and total serum 0.01 x 103/mm3 in the other virus group. Although immunoglobulin E levels none of the 3 groups showed a prevalence of The investigation of the medical history of eosinophilia, the cases with rhinovirus isolation children with asthma exacerbation and an isolated had higher blood eosinophil levels compared to virus included allergic rhinitis, atopic dermatitis, the other 2 groups. Total IgE levels in serum were and a family history of asthma or allergies. The measured in children with asthma exacerbation incidence of atopy was not higher in children and an isolated virus; the average total serum with asthma exacerbation and an isolated virus. IgE level was 299 U/L in the rhinovirus group; In relation to serum eosinophil levels in children 271 U/L in the enterovirus group; and 679.9 U/L with asthma exacerbation and an isolated virus, in the other virus group, Although total serum IgE it was observed that the average eosinophil level levels in children with asthma exacerbation and was 0.31 x 103/mm3 in the rhinovirus group, an isolated virus were higher, when a correlation 0.18 x 103/mm3 in the enterovirus group, and was established between serum eosinophil and total serum IgE levels in the 3 groups, a positive correlation was observed in the rhinovirus group, which was 0.89 with a p= 0.0001, and in the TABLE 2. Isolated respiratory viruses enterovirus group, which was 0.81 with a p= 0.01 Virus % Number (Figure 1). Rhinovirus 26.9 14 Enterovirus 19.2 10 DISCUSSION Respiratory syncytial virus B 9.6 5 The prevalence of asthma varies from one Respiratory syncytial virus A 7.6 4 Bocavirus 7.6 4 region to another.