4.1 Synopsis of key finding
Here, we have investigated the outcome of using fluticasone propionate
topically in 25 case of COE. As presented in the section above, all
cases who returned to the follow up reported significant improvement and
showed resolution of symptoms. When applied topically, fluticasone
propionate, a potent corticosteroid, relieves pruritic and inflammatory
symptoms through binding and activation of glucocorticoid receptors.
(12) It should be noted that more than 70% of our patients used
treatment modalities which contained some corticosteroids, with
Sofradex® and Gentisone HC ear drops being the most
common ones. A comparison between the steroid concentration of all three
drops, shows that daily dosage of fluticasone propionate contains
significantly higher concentration of corticosteroids, compare to the
other two drops. Sofradex® ear drop (0.5% w/v of
Framycetin, Sulphate 0.005% w/v of Gramicidin and 0.050% w/v of
Dexamethasone) contains 50 micrograms of corticosteroid per 100 ml (13),
and it delivers 0.3 micrograms of corticosteroid to the external ear
canal when applied in its maximum daily dose. Gentisone HC ear drops
(Gentamicin 0.3% w/v and Hydrocortisone acetate 1% w/v Ear Drops)
contains 1000 micrograms of corticosteroid per 100 ml (14); which is
equivalent to 8 micrograms of steroid per day when it is applied in its
maximum dose. Given that our cases received 200 micrograms of
fluticasone propionate daily, the significant difference in the amount
of highly potent corticosteroid delivered to the external ear canal
could explain the successful response observed in cure rate of resistant
cases with a course of Flixonase® alone.