Chronic Blepharitis due to Demodex: A Prospective Study in Sfax (Tunisia) - Abstract
Introduction: Chronic blepharitis is a common cause of eye irritation and dryness. They are often treated without regard to causal factors such as parasites which are rarely mentioned. Purpose of Work: The aim of this study is to describe the role of Demodex in the pathogenesis of chronic blepharitis, to analyze the epidemiological, clinical, diagnostic and therapeutic particularities and to propose a therapeutic approach. Methods: This is a prospective, case-control study conducted in the mycology parasitology department at the Habib Bourguiba university hospital in Sfax over a 12-month period from October 2015 to October 2016, covering 100 cases with chronic blepharitis and 87 control cases. Clinical examination and eyelash removal were performed with direct examination for qualitative and quantitative analysis, before and after treatment. Results: Demodex was significantly more found in patients than in controls (48% vs 13.8%). Similarly, the quantitative analysis showed a significant difference between the two groups with 52.1% of Demodex (+++) for patients versus 8.3% for controls.The cases with Demodex blepharitis were treated with mercuric oxide (yellow) ophthalmic ointment with a good outcome in 81,3%. Conclusion: Although it is admitted to be a saprophyte of the skin, a large number of arguments argues for the incrimination of Demodex in the etiopathogenesis of chronic blepharitis, hence the interest of eyelashes examination and a parasitic research in front of any chronic blepharitis resistant to usual treatments. In case of positive research, a specific treatment should be prescribed. Its effectiveness is another argument for the etiological diagnosis. Although it is admitted to be a saprophyte of the skin, Demodex seem to be accused in the genesis of the chronic blepharitis