Nasal dysfunction induced by chlorinate water in competitive swimmers

Insights into exercise-induced rhinitis based on nasal aerodynamics induced by airway morphology

BACKGROUND

Exercise-induced rhinitis (EIR) is a poorly understood phenomenon that may be related to increased inspiratory airflow. Characterization of the development of EIR is important to understand contributing factors.

OBJECTIVE

To characterize how different nasal morphologies respond to airflow-related variables during rapid/deep inspiratory conditions.

METHODS

Subject-specific nasal airways were reconstructed from radiographic images. Unilateral airways were classified as Standard, Notched, or Elongated accord to their distinct nasal vestibule morphology. Computational fluid dynamics simulations were performed at various airflow rates.

RESULTS

For all simulated flow rates, average resistance at the nasal vestibule, airflow velocity and wall sheer stress were highest in Notched. Average mucosal heat flux was highest in Standard. Notched phenotypes showed lower mean percent increases from 10 L/min to 50 L/min in all computed variables.

CONCLUSION

Resistance values and airflow velocities depicted a more constricted nasal vestibule in the Notched phenotypes, while perception of nasal mucosal cooling (heat flux) favored the Standard phenotypes. Different nasal phenotypes may predispose to EIR.

Intranasal trigeminal sensitivity to mechanical stimuli is associated with the perception of nasal patency

PURPOSE

The aim of this prospective study was to examine the characteristics of a clinical test for the assessment of nasal trigeminal sensitivity to mechanical stimuli and its association with the perception of nasal patency.

METHODS

Thirty-two normosmic healthy subjects participated (17 women and 15 men; age = 26 ± 3 years). Precisely defined air puffs were used with a flow rate of 2L/min for mechanical stimulation. They were presented to the nasal vestibule, nasal septum, and inferior turbinate with various stimulus durations. Thresholds were measured by single-staircase stimuli with changes in stimulus duration in steps of 10 ms. Trigeminal suprathreshold intensity was rated by subjects for stimulus durations of 200, 300, 400, and 500 ms. Test-retest reliability was examined by intraclass correlations (ICCs) and Bland-Altman plot with limits of agreement. Pearson's correlations were calculated between self-rated nasal patency and nasal trigeminal sensitivity.

RESULTS

As indicated by trigeminal threshold and suprathreshold intensities, the nasal vestibule is the most sensitive area among the three locations, followed by the nasal septum and the inferior turbinate (p < 0.001). Coefficients of correlations between test and retest were 0.76 for thresholds, and 0.56 suprathreshold intensities (p < 0.001). The Bland-Altman analysis showed a good agreement between test-retest values. In addition, significant positive associations between trigeminal suprathreshold intensities and self-rated nasal obstruction were found at the inferior turbinate (r = 0.4, p < 0.05).

CONCLUSION

Reliable assessment of nasal trigeminal sensitivity for air puffs appears to be possible. Nasal trigeminal suprathreshold sensitivity to mechanical stimuli is associated with the perception of nasal patency at the inferior turbinate. This opens a window into the assessment of the perception of nasal airflow in various clinical purposes, especially for patients with sinonasal diseases.

LEVEL OF EVIDENCE: 3

Clinical Evidence of Type 2 Inflammation in Non-allergic Rhinitis with Eosinophilia Syndrome: a Systematic Review

PURPOSE OF REVIEW

Non-allergic rhinitis (NAR) includes different subtypes, among which NAR with eosinophilia syndrome (NARES) is the most important because of severity of symptoms and the high risk of comorbidities. Its pathophysiology is still object of debate, but a crucial role of chronic eosinophilic inflammation has been recognized. The aim of this review is to critically analyze the current evidence regarding the hypothesis that NARES may be considered a type 2 inflammatory disorder.

RECENT FINDINGS

The definition and diagnostic criteria for NARES are not universally shared and adopted, thus generating difficulties in reproducing the results. At present, there is extreme heterogeneity in sampling methods and disagreement in the cut-off of local eosinophilic count to determine a diagnosis of NARES. The PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) standard was applied to identify English-language experimental and clinical articles regarding NARES. The search was performed in April 2021. Twenty-six articles were included. Our data suggest a particular heterogeneity regarding sampling and specific cut-offs adopted for diagnosis of NARES and consensus should be reached. We suggest that eosinophil count should be reported as an absolute value for at least 10 observed rich fields in order to increase the level of standardization. Consensus among authors on this topic should be reached with particular attention to the cut-off for diagnosis. In the future, this limitation may be overcome by the identification of repeatable biomarkers to refine diagnosis and prognosis of NARES. Furthermore, our data strongly suggest that NARES have numerous similarities with clinical features of the most common type 2 diseases such as eosinophilic asthma and chronic rhinosinusitis with nasal polyps (CRSwNP): late onset, association with type 2 comorbidities, selective eosinophilic tissue infiltration, remarkable response to oral and intranasal corticosteroids, and progression in a type 2 CRSwNP.

Evaluation of exercise-induced bronchoconstriction and rhinitis in adolescent elite swimmers

OBJECTIVE

Exercise-induced bronchoconstriction (EIB) without asthma and non-allergic rhinitis is frequently reported in athletes who are facing high-risk of airway dysfunctions such as elite swimmers. Therefore, we aimed to evaluate the effect of exercise on nasal and pulmonary functions, additionally to determine the prevalence of EIB and rhinitis in adolescent elite swimmers.

METHODS

The study included 47 adolescent licensed-swimmers (26 males and 21 females) aged between 10 and 17 years old. The prevalence of asthma and allergic disease and the symptom severity scores measured before and after swimming training were assessed through an interview form which includes information related to our study goal. In addition, acoustic rhinometry was utilized to evaluate nasal airway, spirometry was utilized to evaluate EIB in accordance with standard protocols.

RESULTS

Six swimmers had a history of allergic rhinitis (12.8%), while three (6.4%) had asthma. Post-swim mean forced vital capacity (FVC) was significantly higher than pre-swim FVC (p=0.019) and forced expiratory volume 1 (FEV-l)/FVC ratio was significantly lower than pre-swim FEV-l/FVC ratio (p=0.034). In addition, the prevalence of EIB was 8.5%. Moreover, level of nasal discharge statistically increased in post-swim period (p=0.003).

CONCLUSION

We have documented that swimming cause's nasal discharge but do not effect nasal passages. In addition, we observed that the overall prevalence of EIB in swimmers was not different from that of the general population, furthermore swimming exercise significantly increased FVC of swimmers. Therefore, we concluded swimming training can be recommended for children diagnosed with asthma or allergic rhinitis.

Upper and Lower Respiratory Signs and Symptoms in Workers Occupationally Exposed to Flour Dust

A group of 142 bakers was studied in order to investigate the relationship between higher/lower respiratory signs/symptoms and inflammation biomarkers and occupational exposure to flour dust. A complete upper and lower respiratory tract evaluation was performed. Seven percent of bakers complained of lower respiratory symptoms, while 22% of them complained of upper respiratory symptoms. Fifty five percent of the bakers were allergic, and 37.1% showed sensitization to occupational allergens. Abnormal spirometries were found in 15% of bakers, while fractional exhaled nitric oxide (FeNO) was above the normal reference in 24.5% of them. Moreover, 23.8% of bakers were found to be hyposmic. Population mean peak nasal inspiratory flow (PNIF) was in the normal range even if almost all the workers suffered from neutrophilic rhinitis at nasal cytology with the number of nasal neutrophils increasing with the increase of the duration of exposure to flour dust (p = 0.03). PNIF and FEV1 (forced expiratory volume in the 1st second) showed a positive correlation (p = 0.03; r = 0.19). The Tiffeneau index decreased with the increase of dust (p = 0.017). A similar result was obtained once we divided our population into smokers and non-smokers (p = 0.021). Long-term exposure to bakery dusts can lead to a status of minimal nasal inflammation and allergy.

Exercise and Rhinitis in Athletes

Peak sporting performance requires optimal levels of health and fitness. Rhinitis, with its proven detrimental effects on sleep and mood, and its association with asthma, can clearly compromise athletic ability. Nasal health is therefore of key importance to the athlete. While not a limiting factor in a single exercise effort, the effects of nasal dysfunction can have repercussions in the post-exercise recovery period. Furthermore, it is linked with the development of asthma and may increase susceptibility to upper respiratory tract symptoms. This review aims to investigate the physiology of the nose during exercise, examine the relationship between exercise and nasal dysfunction, and consider the impact that dysfunction may have on an athlete. Lastly, the authors describe the diagnosis and treatment of rhinitis in athletes.

Relationship Between Nasal Cycle, Nasal Symptoms and Nasal Cytology

Background

The nasal cycle is the spontaneous congestion and decongestion of nasal mucosa that happens during the day. Classically, 4 types of nasal cycle patterns have been described: (1) classic, (2) parallel, (3) irregular, and (4) acyclic. Hypothalamus has been considered as the central regulator even if several external factors may influence its activity.

Objective

The aim of the study was to evaluate the presence of a correlation between nasal cycle pattern, nasal cytology and nasal symptoms.

Methods

Thirty healthy volunteers have been enrolled in the study. All subjects completed a Sino-Nasal Outcome Test-22 questionnaire and a Visual Analog Scale (VAS) for nasal obstruction. The nasal cycle was studied by means of peak nasal inspiratory flow. Nasal cytology has been used to evaluate the presence of local nasal inflammation.

Results

Nineteen subjects showed a parallel nasal cycle pattern, while 11 showed a regular one. A parallel pattern was present in 60% of asymptomatic subjects and in 67% of the symptomatic one ( P = 1). VAS for nasal obstruction did not show a significant difference between the 2 patterns of the nasal cycle ( P = .398). Seventeen subjects had a normal rhinocytogram, while 13 volunteers showed a neutrophilic rhinitis; 53.8% of the subjects with a neutrophilic rhinitis showed a parallel pattern, while the remaining 46.2% had a regular one. In the case of a normal cytology, 70.6% of the volunteers had a parallel pattern and 29.4% had a regular one. Differences between the 2 groups were not statistically significant ( P = .575).

Conclusion

Rhinitis with neutrophils seems to not influence the nasal cycle pattern. Based on the present results, the pattern of nasal cycle does not influence subjective nasal obstruction sensation.

No acute effects of an exposure to 50 ppm methyl methacrylate on the upper airways

PURPOSE

The German MAK value of methyl methacrylate has been fixed at 50 ppm. The aim of this study was to evaluate possible acute effects of an exposure to 50 ppm methyl methacrylate on the upper airways of human subjects.

METHODS

Twenty healthy subjects were exposed to 50 ppm methyl methacrylate and to air (sham) in an exposure chamber for 4 h according to a crossover design. Symptoms were assessed by the SPES questionnaire. Olfactory thresholds for n-butanol and mucociliary transport time were measured before and after exposure. Concentrations of interleukin 1ß and interleukin 8 were determined in nasal secretions taken after exposure. mRNA levels of interleukins 1ß, 6 and 8, tumor necrosis factor α, granulocyte-macrophage colony-stimulating factor, monocyte chemotactic protein 1, and cyclooxygenases 1 and 2 were measured in nasal epithelial cells, obtained after exposure. Possible effects were investigated by semiparametric and parametric crossover analyses.

RESULTS

The score of the item "irritation to the nose" was slightly elevated following exposure to methyl methacrylate (p ≤ 0.01). Olfactory functioning was not impaired. Mucociliary transport time did not change. Neither concentrations of interleukins in nasal secretions nor mRNA levels were elevated.

CONCLUSION

Only minor irritating effects on the nose were observed. The acute exposure to 50 ppm methyl methacrylate did not cause any adverse effects. However, the results cannot be extrapolated to chronic exposure.

Human olfactory sensitivity for bourgeonal and male infertility: a preliminary investigation

Olfactory receptor (OR) expression is also present in the sperm cells and could mediate sperm chemotaxis. OR1D2 was the first OR expressed in the testis demonstrated to be involved in chemotaxis and to be expressed also in the nose with a similar behavior. Bourgeonal is the OR1D2 most potent known agonist. Infertility affects ~15 % of couples in western countries and sometimes it is unexplained. This pilot study compared the bourgeonal olfactory thresholds, the ability of sperm to sense the bourgeonal and the frequency of 13 single nucleotide polymorphisms (SNPs) of OR1D2 gene in nine males suffering of unexplained infertility with a control group of 15 healthy males. The mean olfactory threshold for bourgeonal was statistically different between the study group (10.5 ± 3.7; median 12.3) and the control group (14.0 ± 2.8; median 15.5) (p = 0.006). Statistical analysis showed a significantly higher percentage of spermatozoa that migrated toward the capillaries filled with bourgeonal in the control group compared to the study group (p < 0.0001). Sperm migration was equally inhibited in both groups of subjects when, together with bourgeonal, capillaries were filled with undecanal, a strong bourgeonal inhibitor (p = 0.42). The 13 SNPs of OR1D2 revealed a statistically significant difference for allele and genotype frequency of rs769423 in study group versus control group (p = 0.02). The present preliminary study seems to confirm the important role of OR1D2 both in nose and spermatozoa and may explain the idiopathic infertility of the study group. Further studies on larger series are mandatory to confirm our preliminary evidence.