Respiratory and allergic disorders in children with severe and partial immunoglobulin A immunodeficiency.

BACKGROUND: Immunoglobulin A deficiency (IgAD) is the most common primary immunodeficiency. Although most people with selective IgAD (sIgAD) are asymptomatic, many patients often suffer from recurrent respiratory infections and different allergic disorders. Our aim was to investigate connection between subtypes of sIgAD and incidence of respiratory and allergic disorders, as well as connection with lung function changes in children. METHODS: Children with IgAD where divided into two groups; severe IgAD in patients was defined as serum IgA level <7 mg/dL, while partial IgA deficiency diagnosis was made when serum IgA levels was higher than 7 mg/dL but at least two standard deviations (SD) below mean normal concentrations for their age. All patients were evaluated by their clinical and laboratory investigation parameters and compared to control group of children. RESULTS: Group of children with IgAD, severe as well as partial, showed higher prevalence of allergic diseases and total number of infections, compared to controls. There was a statistically significant difference in lung function for peak expiratory flow (PEF), the maximal expiratory flow at 50% of the forced vital capacity (MEF50) and fraction of exhaled nitric oxide (FENO) between group of patients with severe as well as partial IgAD and control group, where children with IgAD showed reduced lung function. CONCLUSIONS: Children with sIgAD are at increased risk for higher number of respiratory infections and developing allergic diseases, resulting in significantly lower pulmonary function which is related with the severity of sIgAD.

Allergen-Specific IgE Measurement: Intermethod Comparison of Two Assay Systems in Diagnosing Clinical Allergy.

BACKGROUND: Our aim was to examine the performance of IMMULITE 2000 assay for specific IgE (sIgE) by comparing it with ImmunoCAP technology in light of a clinical background. METHODS: Measurements of sIgE were done in a selected patient group (N = 569; varied sample size for each allergen) and in a random sample group (N = 100; 8 allergens). sIgE results were correlated with skin-prick test results (selected patients) and medical history (nonselected patients). RESULTS: We have detected fair to excellent correlation and agreement between the results of both assays, despite their methodological differences, both in selected and nonselected patient group (ρc = 0.431-0.976; ρc = 0.390-0.972, respectively). Associations of sIgE levels with skin-prick test (SPT) levels and medical history have shown significant correlation for both assays for majority of tested allergens, where applicable (D. pteronyssinus, cat dander, egg white, milk, peanut, orchard grass, Alternaria tenuis, and common ragweed in selected patients; birch, cat dander, common ragweed, D. pteronyssinus, and orchard grass in nonselected; P < 0.05 for all). CONCLUSIONS: Laboratory testing for sIgE can be successfully accomplished by IMMULITE 2000 immunoanalyzer at a diagnostic accuracy relative to SPT, comparable to the results acquired by CAP technology but not fully comparable on the level of an individual patient.

The effect of mouth breathing on exercise induced fall in lung function in children with allergic asthma and rhinitis.

OBJECTIVES: Exercise induced bronchospasm (EIB) represents a common feature of childhood asthma which is most commonly revealed during free running. On the other hand aerobic exercise shows significant beneficial effects in asthmatics especially on the reduction of the level of systemic inflammation and is recommended as part of its treatment. The aim of this study was to test how mandatory mouth breathing influences the exercise induced level of decrease in lung function according to the level of severity of allergic rhinitis (AR). METHODS: Free 6-minute running test preceded and followed by spirometry done with and without a nose clip a day apart was conducted in 55 children with moderate persistent asthma and AR. Children were divided into two groups according to the severity of nasal symptoms. RESULTS: There was a greater fall in forced expiratory volume in one second after exercise with a nose clip in children with less nasal symptoms than in children with more nasal symptoms (mean ± SD; -5.28 (7.91) vs. -0.08 (4.58), p = 0.0228) compared to testing without the nose clip (mean ± SD; LNS, -1.31 ± 3.89%, p = 0.2408; MNS, -1.47 ± 3.68%, p = 0.2883). CONCLUSION: Our results show that regular mouth breathing due to nasal congestion may lessen the degree of EIB in patients with persistent AR and allergic asthma.

Urates in exhaled breath condensate as a biomarker of control in childhood asthma.

OBJECTIVE: The aim of this study was to (1) investigate the possibility to use urates in exhaled breath condensate (EBC) as a biomarker of airway inflammation and control in childhood asthma and (2) explore their association with other biomarkers of airway inflammation and clinical indices of asthma control (Asthma Control Test [ACT], quality of life [PAQLQ], lung function, prn beta-agonist use, time from last exacerbation [TLE]. METHODS: This cross-sectional study comprised 103 consecutive patients (age 6-18 years) divided in groups of uncontrolled ([NC], n = 53) and controlled asthma ([C], n = 50). Measured lung function and biomarkers included: spirometry, eosinophilic cationic protein (ECP), high-sensitivity C-reactive protein (hs-CRP), exhaled NO (FENO), pH and urates in EBC and exhaled breath temperature (EBT). RESULTS: Statistically significant differences were found between groups for EBC urates, EBC pH and EBT (NC versus C: EBC urates, median [IQR], µmol/L; 10 [6] versus 45 [29], p < 0.001; EBC pH, mean [SD], 7.2 [0.17] versus 7.33 [0.16], p = 0.002; EBT mean [SD], °C; 34.26 [0.83], versus 33.90 [0.60], p = 0.014). EBC urates showed significant association with TLE and FENO (r = 0.518, p < 0.001; r = 0.369, p = 0.007, respectively) in NC, and EBC pH (r = 0.351, p < 0.001), FEV1 (r = 0.222, p = 0.024), ACT (r = 0.654, p < 0.001), PAQLQ (r = 0.686, p < 0.001) and prn salbutamol use (r = -0.527, p < 0.001) in all asthmatics. CONCLUSION: In our study, EBC urates were found to be the best single predictor of asthma control and underlying airway inflammation. Our results provide evidence supporting the potential utility to use EBC urates as an additional non-invasive biomarker of control in childhood asthma.