Component-resolved diagnosis using microarray for diagnosing hypersensitivity to raw fruits in birch pollen sensitized children

PURPOSE: Recently, component-resolved diagnosis (CRD) using microarray technology has been introduced to the field of clinical allergy. This study was aimed to investigate the clinical usefulness of microarray-based IgE detection for diagnosing clinical raw fruit allergy in birch pollen-sensitized children. METHODS: Thirty-one children with allergic disease who had been sensitized to pollen were studied. A pollen-sensitized patient was defined as having an allergen-specific history with concomitant positive skin-prick tests (SPTs) to natural allergen extracts or positive allergen-specific IgE. All subjects underwent SPTs for pollen and fruit. In all subjects, specific IgE to pollen and fruit were measured by ImmunoCAP. Specific IgE antibodies to allergen components were determined by a customized allergen microarray (ISAC). RESULTS: Thirteen of the 31 patients (41.9%) had a history of fruit hypersensitivity with positive SPTs. Measuring IgE to allergen components by ISAC, all the 13 patients with fruit hypersensitivity were positive to at least one of Mal d 1, Pru p 1, Pru p 3, Act d 8, and Act d 2 compared to 12 of the 13 patients (92.3%) who had at least 1 positive IgE to fruits (apple, peach, and kiwi) using ImmunoCAP. The sensitivity of ISAC microarray was 100.0% for the diagnosis of fruit hypersensitivity, but its specificity was 27.7% (5/18). The sensitivity of ImmunoCAP was 92.3%, and its specificity was 83.3%. CONCLUSION: The sensitivity of allergen components tested using microarray for the diagnosis of clinical fruit hypersensitivity in children with pollen allergy was high; however, its specificity was low.

Plasma secreted phospholipase A2 in asthmatic children: correlation with leptin levels and exercise induced bronchoconstriction

PURPOSE: Dysregulated cysteinyl leukotriene (CysLT) synthesis is prominent in exercise-induced bronchoconstriction (EIB). Secreted phospholipase A2 (sPLA2) plays a key regulatory role in the biosynthesis of CysLTs. We previously found that serum leptin levels correlate with (EIB) in children with asthma. The aim of this study was to address the relationship between plasma sPLA2/leptin levels and EIB. METHODS: Sixty-seven prepubertal children between the ages of 6 and 10 years were included in the study. They were asthmatics with EIB (n=25), asthmatics without EIB (n=21), and healthy subjects (n=21). We measured the plasma sPLA2 and leptin levels. We also performed pulmonary function tests at baseline, after bronchodilator inhalation, and after exercise. RESULTS: The sPLA2 and leptin levels were significantly higher in asthmatics with EIB than in those without and control subjects. In addition, sPLA2 levels were significantly correlated with body mass index (Speraman correlation coefficient r=0.343, P=0.023) and leptin levels (partial correlation coefficient r=318, P=0.033). The maximum decrease in % forced expiratory volume in 1 second after exercise was significantly correlated with both PLA2 levels (r=0.301, P=0.041) and leptin levels (r=0.346, P=0.018). CONCLUSION: The sPLA2 and leptin levels were significantly higher in asthmatics with EIB than in asthmatics without EIB and control subjects. In addition, sPLA2 levels were significantly correlated with leptin levels and EIB in asthmatic children.

Serum leptin levels correlate with bronchial hyper-responsiveness to mannitol in asthmatic children

PURPOSE: Epidemiological data indicate that obesity is a risk factor in asthma, however effects related to obesity and adipokines on airway inflammation and bronchial hyper-responsiveness (BHR) have not yet been demonstrated in the human airway. The aim of this study was to investigate the relationship between serum adipokine levels and BHR to mannitol in asthmatic children. METHODS: Serum adipokine levels were measured and pulmonary function tests were perfomed: baseline, postbronchodilator inhalation, methacholine inhalation, and mannitol inhalation. The response to mannitol was expressed as the dose causing a 15% decrease in forced expiratory volume in one second (FEV1) (PD15), and as the response-dose ratio (RDR) (% fall in FEV1/cumulative dose). RESULTS: Sixty-nine prepubertal children between the ages of 6 and 10 years were participated in the study. They comprised asthmatic children (n=40) and healthy (n=29). Twenty-two subjects (55.5%) with asthma had a positive mannitol bronchial provocation test (BPT) result. The body mass index (BMI) was higher in those asthmatics with positive mannitol BPTs than in asthmatics with negative mannitol BPTs and in the control group (19.30 kg/m2 vs. 17.60 kg/m2 vs. 17.93 kg/m2, P=0.035, P=0.046). Serum leptin levels were also significantly higher in asthmatics with positive mannitol BPTs than in asthmatics with negative mannitol BPTs and in the control group (10.58 ng/mL vs. 5.49 ng/mL vs. 6.75 ng/mL, P=0.002, P=0.016). Leptin values were significantly associated with a PD15 (r=-0.498, P=0.022) and RDR to mannitol (r=0.346, P=0.033) in asthmatic children after adjustment for BMI. CONCLUSION: Serum leptin levels were significantly associated with BHR to mannitol in asthmatic children.