Effects of topical nasal steroids and diclofenac on the nasal mucosa during hyperbaric oxygen therapy: a double-blind experimental study

We aimed to evaluate nasal mucosal changes and efficiency of nasal steroids and diclofenac on nasal mucosa during hyperbaric oxygen (HBO) treatment. Forty adult Albino-Wistar rats were randomized into four groups. Group 1 (control group) (n = 10) not exposed to hyperbaric or enhanced oxygen concentrations; group 2 (HBO group) (n = 10) underwent only HBO treatment; group 3 (n = 10) received HBO and intranasal mometasone furoate (10 μl/day); group 4 (n = 10) treated with HBO and diclofenac sodium (10 mg/kg/day ip). Specimens of nasal mucosa were collected after sacrificing and dissection of animals. The specimens were processed for light microscopic evaluation, and then evaluated histopathologically for fibroblastic proliferation and inflammation. Regarding the scores of inflammation, the level of inflammation in the control group was significantly less severe than the other groups (p < 0.05). Evaluation of the fibrosis scores showed that the scores of both groups 2 and 4 were significantly increased (p < 0.05). There were no statistically significant differences between groups 2, 3, and 4 as for fibrosis and inflammation (p > 0.05). Chronic HBO treatment induced mild inflammation of the nasal mucosa. These effects cannot be prevented adequately by administration of nasal steroids and diclofenac.

Environmental pollutants and allergic rhinitis

PURPOSE OF REVIEW

To review the current knowledge of the pathophysiology, epidemiology, and management of environmental pollutants and allergic rhinitis.

RECENT FINDINGS

Both active cigarette smoking and passive exposure to cigarette smoke are associated with chronic rhinitis and sinusitis. Matrix metalloproteinase 9, which is thought to contribute to the pathophysiology of allergy, is elevated in children with passive cigarette smoke exposure compared with controls. Ground-level ozone and particulate matter exposure is associated with an allergic-type response and may increase sensitization to other allergens. Certain occupational exposures can cause nasal irritation and local cytotoxic effects. Evidence suggests that rhinitis symptomatology may often precede the development of occupational asthma.

SUMMARY

Environmental factors have been noted to induce sinonasal mucosal irritation and often contribute to the multifactorial cause of chronic rhinitis and allergic rhinitis. Cigarette smoke is a common irritant that impacts the innate immune function of the sinonasal epithelial cells, and creates local irritation and cytotoxic effects. Both active smoking and exposure to second-hand smoke increase the risk of chronic rhinitis. Many other environmental pollutants are associated with chronic rhinitis, including ozone, particulate matter, and occupational irritants. The management of chronic rhinitis associated with environmental exposures is similar to the management of other types of chronic rhinitis. Although often not feasible, avoidance is probably the most effective course.