Point-of-care blood eosinophil count in a severe asthma clinic setting.

BACKGROUND: One of the main severe asthma phenotypes is severe eosinophilic or eosinophilic refractory asthma for which novel biologic agents are emerging as therapeutic options. In this context, blood eosinophil counts are one of the most reliable biomarkers. OBJECTIVE: To evaluate the performance of a point-of-care peripheral blood counter in a patients with severe asthma. METHODS: The blood eosinophil counts of 76 patients with severe asthma were evaluated by point-of-care and standard analyzers. RESULTS: A significant correlation between blood eosinophils assessed by the 2 devices was found (R2 = 0.854, P < .001); similar correlations were found also for white blood cells, neutrophils, and lymphocytes. The point-of-care device had the ability to predict blood eosinophil cutoffs used to select patients for biologic treatments for severe eosinophilic asthma and the ELEN index, a composite score useful to predict sputum eosinophilia. CONCLUSION: The results of our study contribute to the validation of a point-of-care device to assess blood eosinophils and open the possibility of using this device for the management of severe asthma management.

Vitamin D deficiency and exercise-induced laryngospasm in young competitive rowers.

Exercise-induced dyspnea is common among adolescents and young adults and often originates from exercise-induced bronchoconstriction (EIB). Sometimes, dyspnea corresponds to exercise-induced laryngospasm (EILO), which is a paradoxical decrease in supraglottic/glottic area. Vitamin D deficiency, which occurs frequently at northern latitudes, might favor laryngospasm by impairing calcium transport and slowing striate muscle relaxation. The aim of this study was to evaluate whether vitamin D status has an influence on bronchial and laryngeal responses to exercise in young, healthy athletes. EIB and EILO were investigated during winter in 37 healthy competitive rowers (24 males; age range 13-25 years), using the eucapnic voluntary hyperventilation test (EVH). EIB was diagnosed when forced expiratory volume in the first second decreased by 10%, EILO when maximum mid-inspiratory flow (MIF50) decreased by 20%. Most athletes (86.5%) had vitamin D deficiency (below 30 ng/mL), 29 mild-moderate (78.4%) and 3 severe (8.1%). EVH showed EIB in 10 subjects (27%), EILO in 16 (43.2%), and combined EIB and EILO in 6 (16.2%). Athletes with EILO had lower vitamin D (19.1 ng/mL vs. 27.0 ng/mL, p < 0.001) and higher parathyroid hormone (30.5 pg/mL vs. 19.2 pg/mL, p = 0.006) levels. The degree of laryngoconstriction (post-EVH MIF50 as a percentage of pre-EVH MIF50) was related directly with vitamin D levels (r = 0.51; p = 0.001) and inversely with parathyroid hormone levels (r = -0.53; p = 0.001). We conclude that vitamin D deficiency is common during winter in young athletes living above the 40th parallel north and favors laryngospasm during exercise, probably by disturbing calcium homeostasis. This effect may negatively influence athletic performance.

High prevalence of Anisakis simplex hypersensitivity and allergy in Sicily, Italy.

BACKGROUND: Anisakis simplex can elicit allergic reactions when ingested in raw or marinated fish. The prevalence of A simplex hypersensitivity and allergy in Sicily (Italy), an area where the consumption of raw or marinated fish is very common, has not been investigated thus far. OBJECTIVE: To investigate the prevalence of A simplex sensitization and its clinical relevance in a large group of unselected patients. METHODS: All consecutive patients referred to the authors' allergy clinic during a 22 month-period were included in the study, evaluated for sensitization to A simplex and other allergens depending on their clinical history, and investigated for allergic symptoms after the ingestion of raw or marinated fish. RESULTS: Of 3,419 patients screened, 527 (15.4%) were sensitized to A simplex and 29 of these (5.5% of sensitized patients) had a history of A simplex allergy. Approximately 30% of patients had mono-sensitization to A simplex. Co-sensitization to house dust mites or molds yielded an odds ratio of 1.98 or 3.18, respectively, for allergy to A simplex. CONCLUSION: A high prevalence of A simplex sensitization in a large proportion of patients with mono-sensitization was found, confirming that eating habits influence sensitization to this nematode. Allergic symptoms from A simplex ingestion in raw or marinated fish were quite frequent, with symptoms ranging from oral allergy syndrome to anaphylaxis. Patients sensitized to A simplex were more prone to have allergic symptoms when they had co-sensitization to house dust mites or molds, suggesting possible cross-reactive but clinically relevant allergens between these allergenic sources.

Bronchodilator response as a marker of poor asthma control.

BACKGROUND: Asthma guidelines emphasise the importance of monitoring disease control in managing asthma. OBJECTIVE: The aim of this study was to evaluate the relationship between lung function, including bronchodilator response in terms of improving in FEV1 after administration of salbutamol, and asthma control. METHODS: 246 patients with known asthma and in regular chronic treatment according to international guidelines were consecutively enrolled in a 12 month-period. All patients were evaluated by asthma control test (ACT), spirometry and bronchodilator test with salbutamol 400 mcg. RESULTS: Mean ACT value was 18.8. Patients with significant bronchial reversibility had lower ACT mean values. This finding was confirmed in both patients with airway obstruction and in those with normal spirometry. There was a significant correlation between ACT values and bronchodilator response. CONCLUSIONS: The persistence of a significant degree of bronchodilator response despite regular treatment according to guidelines was a marker of worse asthma control. CLINICAL IMPLICATIONS: Bronchodilator response, correlating with worse asthma control even in patients with normal spirometry, should be test at every visit as it may add information on asthma control.