Pharmacotherapy of Allergic Rhinitis: Corticosteroids

Determinants of the Nasal Microbiome: Pilot Study of Effects of Intranasal Medication Use

Introduction

A role for bacteria and other microbes has long been suspected in the chronic inflammatory sinonasal diseases. Recent studies utilizing culture-independent, sequence-based identification have demonstrated aberrant shifts in the sinus microbiota of chronic rhinosinusitis subjects, compared with ostensibly healthy controls. Examining how such microbiota shifts occur and the potential for physician-prescribed interventions to influence microbiota dynamics are the topics of the current article.

Methods

The nasal cavity microbiota of 5 subjects was serially examined over an 8-week period using pan-bacterial 16S rRNA gene sequencing. Four of the subjects were administered topical mometasone furoate spray, while 1 subject underwent a mupirocin decolonization procedure in anticipation of orthopedic surgery.

Results

Measures of microbial diversity were unaffected by intranasal treatment in 2 patients and were markedly increased in the remaining 3. The increase in microbial diversity was related to clearance of Moraxella spp. and a simultaneous increase in members of the phylum Actinobacteria. Both effects persisted at least 2 weeks beyond cessation of treatment. Transient changes in the relative abundance of several bacterial genera, including Staphylococcus and Priopionibacteria, were also observed during treatment.

Conclusions

The effects of intranasal steroids on the sinonasal microbiome are poorly understood, despite their widespread use in treating chronic sinonasal inflammatory disorders. In this longitudinal study, administration of intranasal mometasone furoate or mupirocin resulted in shifts in microbial diversity that persisted to some degree following treatment cessation. Further characterization of these effects as well as elucidation of the mechanism(s) underlying these changes is needed.

Comparison of Intranasal Hypertonic Dead Sea Saline Spray and Intranasal Aqueous Triamcinolone Spray in Seasonal Allergic Rhinitis

Intranasal corticosteroids are well known to be efficacious in the treatment of allergic rhinitis. Nasal irrigation with saline, including hypertonic saline, has long been recommended for the treatment of sinonasal disease, and it has been shown to have a positive effect on the physiology of the nasal mucosa. Until now, no study of the clinical efficacy of intranasal hypertonic Dead Sea saline as a monotherapy for seasonal allergic rhinitis has been reported. We conducted a prospective, randomized, single-blind, placebo-controlled comparison of intranasal hypertonic Dead Sea saline spray and intranasal aqueous triamcinolone spray in 15 patients with seasonal allergic rhinitis. Results were based on a 7-day regimen. Based on Rhinoconjunctivitis Quality of Life Questionnaire scores, clinically and statistically significant (p < 0.0001) improvements were seen in both active-treatment groups; as expected, the corticosteroid spray was the more effective of the two treatments. No significant improvement occurred in the control group. Our preliminary results not only confirm the efficacy of intranasal corticosteroid therapy in moderate-to-severe allergic rhinitis, they also suggest that the Dead Sea saline solution can be an effective alternative in mild-to-moderate allergic rhinitis, particularly with respect to nasal and eye symptoms. The hypertonicity of the Dead Sea solution may have a positive effect on the physiology of the nasal mucosa by improving mucociliary clearance. In addition, the dominant cation in the Dead Sea solution— magnesium— probably exerts anti-inflammatory effects on the nasal mucosa and on the systemic immune response.