Chronic rhinosinusitis: phenotypes and endotypes.

PURPOSE OF REVIEW: Chronic rhinosinusitis (CRS) is a broad classification of airway inflammation that affects a significant portion of the population. The current model of delineating patients suffering from CRS is dated and is no longer as simple as the presence of polyps or no polyps. Continued advances in the endotype descriptions of CRS have allowed for new phenotypic descriptions that aid in driving management and research efforts. RECENT FINDINGS: Geographic differences exist between patient presentations, which require a molecular evaluation of the driving forces. Increased understanding of these differences allows for patient-specific treatment decisions. SUMMARY: New descriptions of CRS phenotypes allow for more targeted therapy for patients, particularly to those with difficult to control disease. The previously broad classification of CRS with or without nasal polyps is no longer sufficient at driving these treatment decisions.

In-vitro evaluation of a ciprofloxacin- and ivacaftor-coated sinus stent against Pseudomonas aeruginosa biofilms.

BACKGROUND: We recently developed a novel ciprofloxacin-coated sinus stent capable of releasing antibiotics over a sustained period of time. Ivacaftor is a cystic fibrosis transmembrane conductance regulator (CFTR) potentiator that has synergistic bactericidal activity with ciprofloxacin and also enhances sinus mucociliary clearance. The objective of this study was to optimize and evaluate the efficacy of a ciprofloxacin- and ivacaftor-releasing biodegradable sinus stent (CISS) in vitro. METHODS: A CISS was created by coating ciprofloxacin/ivacaftor-embedded nanoparticles with an acrylate and ammonium methacrylate copolymer onto a biodegradable poly-L-lactic acid stent. In-vitro evaluation of the CISS included: (1) assessment of drug stability in nanoparticles by zeta potential, and drug-coating stability within the CISS using scanning electron microscopy (SEM); (2) determination of ciprofloxacin- and ivacaftor-release kinetics; and (3) assessment of anti-Pseudomonas aeruginosa biofilm formation by calculating relative optical density units (RODUs) compared with control stents at 590-nm optical density. RESULTS: The presence of drugs and a uniform coating on the stent were confirmed by zeta potential and SEM. Sustained drug release was observed through 21 days without an initial burst release. Anti-biofilm formation was observed after placing the CISS for 3 days onto a preformed 1-day P aeruginosa biofilm. The CISS significantly reduced biofilm mass compared with bare stents and controls (RODUs at 590-nm optical density; CISS, 0.31 ± 0.01; bare stent, 0.78 ± 0.12; control, 1.0 ± 0.00; p = 0.001; n = 3). CONCLUSION: The CISS maintains a uniform coating and sustained delivery of drugs providing a marked reduction in P aeruginosa biofilm formation. Further studies evaluating the efficacy of CISS in a preclinical model are planned.