Altered Viscosity of Nasal Secretions in Postnasal Drip

Mucoadhesion across scales: Towards the design of protein-based adhesives

Mucoadhesion is a special case of bioadhesion in which a material adheres to soft mucosal tissues. This review elucidates our current understanding of mucoadhesion across length, time, and energy scales by focusing on relevant structural features of mucus. We highlight the importance of both covalent and non-covalent interactions that can be tailored to maximize mucoadhesive interactions, particularly concerning proteinaceous mucoadhesives, which have been explored only to a limited extent so far in the literature. In particular, we highlight the importance of thiol groups, hydrophobic moieties, and charged species inherent to proteins as key levers to fine tune mucoadhesive performance. Some aspects of protein surface modification by grafting specific functional groups or coupling with polysaccharides to influence mucoadhesive performance are examined. Insights from this review offer a physicochemical roadmap to inform the development of biocompatible, protein-based mucoadhesive systems that can fulfil dual roles for both adhesion and delivery of actives, enabling the fabrication of advanced biomedical, nutritional and allied soft material technologies.

Posterior Nasal Nerve Ablation as a Viable Treatment Option for the Primary Symptom of Postnasal Drip

BACKGROUND

Postnasal drip (PND) syndrome is a prevalent complaint encountered in otolaryngology practices. PND may be refractory to medical therapy, and surgical treatments are complicated by side effects.

OBJECTIVE

While posterior nasal nerve (PNN) ablation has demonstrated efficacy for chronic rhinitis overall, we sought to examine the effect of PNN ablation for patients with PND as their primary complaint.

METHODS

This is a retrospective case series study of 40 chronic rhinitis (CR) patients with a primary complaint of PND. Included patients had to have failed medical therapy such as anti-cholinergic nasal sprays, reflux treatments, and/or nasal steroids. Primary outcome measures included 22 item Sino-Nasal Outcome Test (SNOT-22) PND component and Total Nasal Symptom Score. Secondary outcome measure was subjective improvement, defined as a  > 30% improvement in PND symptoms.

RESULTS

Median follow-up was 138 days (interquartile range: 72-193). 72.5% (29/40) of patients reported at least a 30% improvement in PND symptoms. Mean PND SNOT-22 scores were 4.2/5 (SD = 0.8) pre-procedure versus 1.9/5 (SD = 1.3) post-procedure (P = .001). PNN ablation response did not correlate to ipratropium bromide nasal spray response, although younger and non-smoker patients had better response rates.

CONCLUSION

This exploratory study of PNN ablation for the primary symptom of PND demonstrates efficacy as assessed by the PND component of SNOT-22 and subjective improvement. These results can be useful in guiding physician-patient discussions in determining treatment options for medically refractory PND.

Postnasal Drip

Postnasal drip (PND) is a common symptom encountered when evaluating subjects with sinonasal disease; it may be present without sinonasal disease or as a symptom of laryngopharyngeal reflux. It is postulated that PND stems from dysfunction of normal mucus clearance mechanisms; however, there is no definitive evidence elucidating an exact pathophysiology. Compounding the uncertainties surrounding PND is the lack of an objective assessment tool. Instead, treating physicians must rely on subjective complaints and investigators utilize validated patient-reported outcome instruments, such as the Sino-Nasal Outcome Test, to determine treatment efficacy. This review seeks to discuss the current understanding of PND and evidence regarding effective treatment strategies.

The Nasal Endoscopic Features of Postnasal Drip: A Cross Sectional Study

Introduction  Patients with chronic rhinitis suffer from postnasal drip (PND) but this symptom is not well addressed. Nasal endoscopy may aid in identifying PND. Well described endoscopic features of PND are presence of secretions in the posterior nasal cavity, diffuse erythema, and hemorrhagic spots in the nasopharynx, but these have not been formally studied. Objectives  The present study aims to assess the association of nasal endoscopic features with PND among rhinitis patients. This will guide clinicians to interpret the nasal endoscopic findings appropriately. Methods  Adults (≥ 18 years old) with chronic rhinitis were consecutively recruited at an Otorhinolaryngology outpatient clinic in a tertiary referral center. The patients were grouped into either "Rhinitis with PND" or "Rhinitis only." The endoscopic features of PND were scored as: Secretions in the posterior nasal cavity (yes/no), erythema in the nasopharynx (none, roof only, diffuse), hemorrhagic spots (yes/no), then were compared between groups. Results  There were 98 patients included (age 32.32 ± 11.33 years old, 61.2% female, 61.2% PND). Presence of secretions in the posterior nasal cavity was associated with PND ("Rhinitis with PND" versus "Rhinitis only," 78.3 versus 55.3; p  = 0.02; Odds ratio: 2.81; 95% confidence interval [CI]: 1.08-7.32). Diffuse erythema of the nasopharynx was more frequent in "rhinitis only" compared with those with PND (76.3 versus 53.3%; p  = 0.02). Hemorrhagic spots were equally present in both groups (11.7 versus 18.4%; p  = 0.35). Conclusion  Presence of secretions in the posterior nasal cavity may indicate bothersome PND among patients with rhinitis. Diffuse erythema of the nasopharynx and hemorrhagic spots are a nonspecific sign of inflammation.

Recent progress in the management of chronic cough

Chronic cough is a common clinical condition with significant impact on quality of life and for which effective therapy remains an unmet clinical need. Over the past decade, there has been a major shift in how we approach this problem, driven by better appreciation of the clinical manifestation of chronic cough and an improved understanding of the associated neurobiology. "Cough hypersensitivity syndrome" has been proposed as a new diagnostic term for chronic cough, encompassing different phenotypes of the condition. Accumulating evidence suggests that this new concept is clinically relevant. However, while it is gaining widespread endorsement within the allergy and respiratory community, raising its profile in routine clinical practice is a priority. Thus, the present paper reviews recent progress in our understanding and management of chronic cough, with focus on mechanistic and clinical studies. It also provides detail on knowledge gaps and future research directions.

Exploring the clinical relevance of cough hypersensitivity syndrome

Introduction: Knowledge of the pathophysiology of cough has continued to advance over recent decades. Establishing anatomic-diagnostic protocols, based on the anatomy and distribution of vagus nerve pathways regulating the cough reflex, was the first breakthrough in modern clinical medicine for chronic cough. The unmet clinical need has prompted revised thinking regarding the pathophysiology of and the clinical approach to chronic cough.Areas covered: The paradigm of cough hypersensitivity syndrome (CHS) has been recently proposed, wherein aberrant neuro-pathophysiology is a common etiology. This review covers major findings on chronic cough and cough hypersensitivity, particularly focused on recently-published studies and explores the clinical relevance and applicability of CHS based on current knowledge and discuss knowledge gaps and future research directions.Expert opinion: This paradigm has provided new opportunities in managing chronic cough and evidence is accumulating to support the validity of CHS. It also warrants the re-appraisal of existing clinical evidence and investigation of how to refine our clinical strategy. While CHS highlights the importance of clinical thinking from the viewpoint of cough, the value of anatomic-diagnostic protocols should remain. Moreover, given the considerable heterogeneity in clinical presentation, cough-associated disease conditions, and treatment responses across different patients, precise molecular endotyping remains key to making further to advancing clinical practice .