Allergic nasal mucosa following topical treatment with beclomethasone dipropionate (Bdp) aerosol. Electron microscopic study

Intranasal Steroids and the Myth of Mucosal Atrophy: A Systematic Review of Original Histological Assessments

Background

Intranasal corticosteroids (INCSs) are well established in the treatment of allergic rhinitis, chronic rhinosinusitis, and nasal polyposis. Although reversible atrophy of keratinized skin is seen with corticosteroids, the respiratory mucosa is histologically very different and but concerns remain among patients and some health-care professionals over local side effects on nasal respiratory mucosa. A systematic review and meta-analysis were performed of the available evidence for nasal mucosal atrophy as an adverse effect of INCSs in patients with sinonasal disease.

Methods

A systematic search of Embase (1974-) and Medline (1946-) databases to September 27, 2013 was performed. Inclusion criteria selected any study where the histopathology of nasal mucosa was assessed in patients with sinonasal disease using intranasally administered corticosteroids with or without a control group.

Results

Twenty-three hundred sixty-four publications were retrieved with a subsequent full text review of 149 publications for 34 articles that met the selection criteria. These articles included 11 randomized controlled trials, 5 cohorts, and 20 case series. Duration of treatment varied from 5 days to 5.5 years. “Mucosal atrophy” as an outcome was reported in 17 studies. The definition of “mucosal atrophy” was highly variable with a definition given in only 10 studies. One hundred thirty-six patients were represented in controlled studies of atrophy with only one study reporting the event in both groups with an odds ratio of “mucosal atrophy” at 0.51 (95% CI, 0.09-3.11; p = 0.47).

Conclusion

The concept of nasal mucosal atrophy is poorly defined and there is no histological evidence for deleterious effects from INCS use on human nasal mucosa.

Pathology of the eustachian tube in otitis media: an electron microscopic study

The ultrastructure of the mucosa of the eustachian tube was studied in four temporal bones showing tympanosclerosis, cholesteatoma, otitic meningitis and a grafted tympanic membrane (tympanoplasty). The mucosa of tube was abnormal in the four cases confirming the relationship between the state of the eustachian tube and the inflammatory process in the middle ear. The observed abnormalities included: ciliary loss, abnormal ciliary morphology and motility, oedema of the microvilli, hyperplasia of the goblet cells and the seromucinous acini, desquamation of the non-ciliated cells and appearance of mast cells in the lamina propria of the tube. Ciliary changes were the most frequent abnormalities and the morphological changes, in general, were fewest in the case of healed tympanoplasty. The pathophysiology of the morphological changes was discussed and correlated with the disease in the middle ear.

Laser surgery for allergic rhinitis: the effect on seromucinous glands

Ten patients with perennial allergic rhinitis were subjected to CO2 laser turbinectomy. Tiny (1 mm3) biopsy specimens were taken at the time of surgery and 1 month thereafter. The biopsy specimens were processed for transmission electron microscopy. Also, the activity of succinic dehydrogenase and cholinesterase enzymes was measured. The study showed that laser turbinectomy was followed by reduction in the number and activity of the glandular acini in the laser-treated areas. This reduction is ascribed to the local destructive effect of laser energy on the glandular acini and on the surrounding cholinergic nerve fibers. The enzymatic activity of the cholinergic nerve fibers themselves, however, did not diminish, indicating that laser surgery has no inhibitory effect on the local allergic reaction.

Topical levocabastine for the treatment of perennial allergic rhinitis

The ultrastructure of the nasal mucosa following the use of intranasal levocabastine was studied in 20 patients suffering from perennial allergic rhinitis. The patients received twice daily 0.05 per cent levocabastine spray with a treatment duration of four weeks. At the end of the treatment period regression of the allergic process was evidenced by progressive reappearance of normal cilia and microvilli on the columnar cells, decrease of intercellular oedema and cytoplasmic vacuoles, increased number of mucous acinar cells, gradual decrease of vascular congestion, as well as diminished oedema fluid formation. The drug, however, had no effect on mast cell degranulation nor on eosinophilic infiltration. Normalization of the ultrastructural features correlated well with clinical improvement. Considering the results of the present study, levocabastine nasal spray appears to be an effective treatment for perennial allergic rhinitis and can be used with, or as an alternative to, other anti-allergic medications.

Effect of 3 months' nasal steroid therapy on nasal T cells and Langerhans cells in patients suffering from allergic rhinitis

The effect of nasal corticosteroid therapy on allergic rhinitis is uncertain. In a double-blind, placebo-controlled study over 3 months, we investigated the influence of a new corticosteroid spray, fluticasone propionate aqueous nasal spray (FPANS), on Langerhans cells (CD1a+ cells), HLA-DR+ cells, and T cells in nasal mucosa. Efficacy was evaluated by nasal symptom score. This treatment significantly decreased the number of CD1a+ cells and HLA-DR+ cells in the nasal mucosa. Furthermore, a clear trend of decreasing numbers of T cells in nasal epithelium was found. No change in nasal symptom score was found after the treatment period. These findings suggest that fluticasone propionate aqueous nasal spray decreases the antigen presentation in nasal allergy.

In vitro effect of beclomethasone dipropionate and flunisolide on the mobility of human nasal cilia

Human nasal cilia were perfused with aqueous solutions of two corticosteroid aerosols, beclomethasone dipropionate (BPD) and flunisolide, with the main preservative of flunisolide, propylene glycol, and with placebo. The concentration used were BPD 0.1 mg/ml, 0.05 mg/ml, 0.005 mg/ml and 0.0005 mg/ml, flunisolide 0.25 mg/ml, 0.05 mg/ml, 0.025 mg/ml and 0.00025 mg/ml, and propylene glycol 20 mg/ml and 200 mg/ml. A dose-related decrease in ciliary beating frequency (CBF) was seen after perfusion with both BDP and flunisolide as well as propylene glycol. The decrease in CBF following perfusion with propylene glycol was partially reversible upon re-perfusion with medium alone, whereas the decrease seen after BDP and flunisolide was irreversible. Although previous studies have shown no adverse effect on the mucous membrane except for the areas hit by the impact of the sprays, our results suggest that caution should be taken when the dose and/or the length of treatment is considered, and that the effect of administration of these drugs on CBF in vivo needs to be investigated.