Mast cell (MC) mediators, among them prostaglandin D₂ (PGD₂) and 9α,11β-PGF₂, PGD₂’s metabolite, play a key role in allergic reactions, including bee venom anaphylaxis (BVA). Assessment of these mediators has never been performed in BVA. The aim of the study was to assess the activation of MC during in vivo provocation with bee venom (BV) and to measure PGD₂ and 9α,11β-PGF₂ in the course of an allergen challenge. The second aim was to determine if assessment of these mediators could be useful for predicting adverse events during venom immunotherapy (VIT). In 16 BV-VIT patients and 12 healthy subjects, levels of PGD₂ and 9α,11β-PGF₂ were assessed during BV provocation by means of the skin chamber method. Chamber fluids, collected at 5 and 15 min, were analyzed for both mediators by gas chromatography mass spectrometry negative ion chemical ionization. BVA in comparison to non-allergic patients had a significantly higher ratio of 9α,11β-PGF₂ in allergen-challenged chambers to 9α,11β-PGF₂ in allergen-free chambers after 15 min of provocation (p = 0.039). Allergen challenge resulted in a significant increase of 9α,11β-PGF₂ levels between 5 and 15 min after provocation only in BVA patients (p < 0.05). Analysis of log-transformed PGD2 levels showed significant difference between changes in PGD₂ concentration between BVA and healthy subjects. No study patient developed adverse reactions during. 9α,11β-PGF₂ is actively generated during the early allergic response to BV. Skin chamber seems to be a promising, non-invasive and safe model of in vivo allergen provocation in BV-allergic patients. High or low levels of both mediators do not predict occurrence of adverse events during VIT.

Introduction: Assessment of nitric oxide (NO) concentration in exhaled air is broadly used to monitor the airway inflammation in asthma. High levels of NO are also observed in paranasal sinuses and gastrointestinal tract (GT). Properly functioning esopahageal sphincters are responsible for maintaining NO in the GT. So far, it has been unknown how much the GT disorders and especially the disorder of esophageal motility can affect FeNO (fractional exhaled nitric oxide) measurements. The aim of the study was to assess whether the gastroesophageal reflux disease has any impact on the level of NO in the exhaled air in patients who do not suffer from any airway diseases. Material and methods: Gastroscopy with biopsy was performed in 51 patients, in whom asthma, allergic rhinitis and atopy were excluded. In 13 of them, no esophageal pathology was found and they were considered as the control group. In the remaining 38 patients, the severity of esophagitis was evaluated according to the Los Angeles classification. Results: The concentration of NO in the exhaled air of patients with endoscopic gastroesophageal changes did not differ significantly from NO concentration in patients without inflammatory changes in the stomach and esophagus (p = 0.68). The presence of the hiatal hernia did not affect the FeNO concentration either (p = 0.67). There was no statistically significant correlation between the NO level and infection with Helicobacter pylori (p = 0.18). Conclusions: The gastroesophageal pathologies did not affect the NO concentration in exhaled air significantly.

Introduction: Fractional exhaled nitric oxide (FeNO) is considered a useful, noninvasive marker of airway inflammation in asthma and allergic rhinitis. It has also been suggested that anti-inflammatory treatment guided by monitoring of exhaled NO could improve overall asthma control. However, long-term intrasubject variability of this parameter as well as the rate of its change, which can be considered clinically significant, have not been established yet. The aim of our study was to assess the long-term variability of FeNO in pregnant asthmatic women with controlled asthma. Material and methods: Pregnant, non-smoking women with asthma were recruited at between 3 and 6 months of gestation. Exhaled nitric oxide (FeNO) spirometric parameters were measured, and asthma control tests (ACT) were completed at monthly visits up to delivery. The data of 26 subjects with well controlled asthma during pregnancy (ACT values within the range 20–25, normal spirometric parameters, stable treatment) were analysed. The variability of FeNO values was assessed using the variation coefficient CV (standard deviation × 100%/arithmetic mean). Results: The median level of FeNO coefficient of variation (CV) was: 33.8% (range 11.3 to 121.9) in all subjects with well controlled asthma during pregnancy. There were no statistically significant differences in FeNO variability between groups of patients who had at least one measurement of FeNO higher than 50 ppb (39%; 11.8–121.9%) and those with all FeNO values below 50 ppb (29.9%; 11.3–71.8%), as well as between atopic (35.7%; 11.8–121.9%) and nonatopic (24.2%; 11.3–71.8%) pregnant asthmatics (p = 0.95 and 0.11, respectively). Conclusions: High long-term variability of fractional exhaled nitric oxide values revealed in pregnant women with well controlled asthma indicates that changes in this parameter should be interpreted with caution when used for asthma treatment monitoring.