Allergic rhinitis and immunoglobulin deficiency in preschool children with frequent upper respiratory illness.

Background: Frequent upper respiratory illness (URI) is a common problem in preschool children. Allergic rhinitis and immunoglobulin (Ig) deficiency are usually suspected as underlying etiologies. Objective: To determine the prevalence of allergic rhinitis and Ig and IgG subclass deficiency in preschool children with frequent URI. Methods: Two thousand eight hundred and seventy-six questionnaires were distributed to the parents of children aged 3-6 years in 24 kindergartens. Firstly, they determined the frequency of URI in the previous year and secondly the prevalence of rhinitis according to the International Study of Asthma and Allergies in Childhood (ISAAC) questionnaire. The skin prick test (SPT) was performed and serum Ig and IgG subclasses were measured in children with frequent URI (>10 episodes per year). Allergic rhinitis was diagnosed when the child had had rhinitis in the previous 12 months and positive SPT for at least 1 aeroallergen. Results: Two thousand three hundred and one questionnaires (80.01 %) were returned. Ninety-four out of 219 children with frequent URI participated in the study. The prevalence of allergic rhinitis in the participants was 42.55%. Exclusive breastfeeding for at least 6 months had a protective effect, while paternal history of rhinitis was a risk factor. All participants had normal serum IgG, IgA, IgM and IgG subclass levels for age. Conclusion: The prevalence of allergic rhinitis in preschool children with frequent URI in our study was 42.55%. Allergic rhinitis should be considered if they have a family history of allergic rhinitis. Immunoglobulin deficiency was not found in our study.

Comparison of salbutamol efficacy in children- via the metered-dose inhaler (MDI) with Volumatic® spacer and via the dry powder inhaler, Easyhaler®, with the nebulizer - in mild to moderate asthma exacerbation: a multicenter, randomized study.

Background: β2 agonist administered via a nebulizer is the standard treatment for acute asthma exacerbation. There are some limitations for the use of nebulization. We conducted a study to determine the efficacy of salbutamol administered via the pMDI with Volumatic® spacer and the Easyhaler®(DPI) compared to nebulization in mild to moderate asthma exacerbations in children. Methods: A multicenter, randomized, controlled study was conducted in children between 5 and 18 years of age who presented at an emergency or outpatient department. They were randomized to receive either 6 puffs of salbutamol via the pMDI with Volumatic® spacer, or via the Easyhaler®, or 0.15 mg/kg of salbutamol nebulized via oxygen (or compressed air). The primary outcome was the clinical response which was assessed using the modified Wood’s asthma score. The secondary outcomes were: hospitalization, asthma re-visit within 3 days, systemic corticosteroid use and adverse events. The clinical score, oxygen saturation, PR, RR, BP and adverse events were recorded at time 0 (before treatment) and 20, 40 and 60 minutes after drug administration. Results: There were no statistically significant differences in the clinical response between the three groups at the 1st, 2nd or 3rd dose or for the SpO2 or the respiratory rate while the children in the Easyhaler® group had significantly less tachycardia after the 2nd dose. No significant adverse events were noted among the three groups. Conclusions: Salbutamol administered via pMDI with Volumatic® spacer or DPI (Easyhaler®) are as effective as salbutamol given via a nebulizer in providing effective relief of mild to moderate severity acute asthma exacerbation in children between 5 and 18 years of age.

X-linked agammaglobulinemia in northern Thailand.

X-linked agammaglobulinemia (XLA) is a primary immunodeficiency characterized by a failure to generate immunoglobulins of all isotypes due to the absence of mature B cells and plasma cells, secondary to mutations in the Bruton's tyrosine kinase (Btk) gene. We report six patients with XLA, confirmed by mutation analysis, from northern Thailand. The mean age of onset was 2.5 years and the mean age at diagnosis was 7.3 years. All patients had a history of otitis media, pneumonia and arthritis at the time of diagnosis, five patients had developed bronchiectasis and 3 patients septicemia. Other infections reported included sinusitis (5/6), pericarditis (1/6), meningitis (1/6) and pyoderma (1/6). Haemophilus influenzae, Streptococcus pneumoniae, Pseudomonas aeruginosa and Staphylococcus aureus were isolated on multiple occasions. One patient died of sepsis at the age of 16 years. These observations demonstrate that early diagnosis and treatment can improve prognosis and quality of life.

House dust mite allergen levels in Chiang Mai homes.

The quantitative assays for house dust mite (HDM) allergens provide a valid index of exposure and can be used for risk evaluation. We assessed group I HDM allergen levels in mattress and living room floor dust from 35 Chiang Mai homes and identified factors associated with high allergen levels. One-third of mattress and living room floor dust had group I HDM allergen levels of between 2-10 microg/g. Two-thirds of mattress dust and a small amount of living room floor dust had group I HDM allergen levels of over 10 microg/g. The geometric means of Der p I, Der f I and total group I allergens in mattress and living room floor dust were 8.61, 2.88, and 15.81 microg/g and 1.61, 0.27 and 2.43 microg/g, respectively. Mattresses made of kapok and rugs kept in the living room were associated with high group I allergen levels.

Sensitization to Dermatophagoides pteronyssinus and Blomia tropicalis extracts and recombinant mite allergens in atopic Thai patients.

Mite surveys in Thailand indicated that Dermatophagoides pteronyssinus (Dp) is predominant, but so far there were no data available on Blomia tropicalis (Bt), which is prevalent in the Asia Pacific region. Skin prick testing (SPT) was performed in 40 atopic children, 45 atopic adults and 17 non-atopic volunteers. Skin reactions to Dp were found in 25/40 (62.5%) and 23/45 (51.1%); skin reactions to Bt were found in 15/40 (37.5%) and 18/45 (40%) in atopic children and adults, respectively. SPT to the major sensitizing allergens Der p 1, Der p 2, Der p 5, and Blo t 5 showed positive results in 14/40 (35%), 12/40 (30%), 1/40 (2.5%) and 4/40 (10%) of atopic children, and in 12/45 (26.7%), 13/45 (28.9%), 5/45 (11.1%), 6/45 (13.3%) of atopic adults, respectively. The results indicate that Dp is one of the major sources of allergy, while Bt is a minor one and that Der p 1 and Der p 2 are important mite allergens in Chiang Mai, Thailand.