PARASITIC MITES IN HUMAN EYELASHES AND EYELIDS. PREVALENCE ANALYSIS OF DEMODEX FOLLICULORUM IN OPHTHALMOLOGICAL CONSULTATIONS IN THE CITY OF CORDOBA, ARGENTINA.

Abstract

This is a prevalence study on Demodex folliculorum infection, a parasitic mite of human eyelashes, eyelids and meibomian glands ducts. This type of mites frequently appears in opthalmologic consultations. Patients present blepharitis with pruritus, burning sensation, irritation and eye pain, which are quickly relieved after diagnosis and mite treatment.1,4,14, 30, 31 All the patients who visited the ophthalmology office in the Chair of Ophthalmology at Hospital Nacional de Clinicas, School of Medicine, National University of Cordoba, Argentina, were included in this research. The objective was to determine the presence of this mite in opthalmologic consultation when blepharitis was diagnosed, and secondly, define what type of symptoms and signs appear with this condition. The total number of patients seen in the 243 working days of the year 2012 were 48,600 (n=48,600). Half of these patients (n=24,300) were diagnosed with blepharitis; in 30% of the cases (n=7230), blepharitis was due to the mite. From this, we conclude that 15% of the patients consulted because of blepharitis caused by Demodex folliculorum. In our experience mite infection is always associated with blepharitis. Other authors, 7,16,19 have pointed to the presence of mites without symptoms. Blepharitis is defined as eyelid inflammation and we could determine that 100% of these patients presented eye pruritus, 60% dry eye sensation, 50% tearing, 40% burning, 30% eye pain, 30% discharges and 20 % blurred vision. This condition becomes chronic and in occasions it may cause loss of eyelashes. In most cases, patients take a long time before seeing a doctor because of this condition. It is surprising to see this kind of mites moving around eyelashes. This study exposes the high prevalence of mite blepharitis taking into account an important sample of opthalmologic consultations and tries to statistically contextualize the condition and inform medical professionals about these results. Finally, blepharitis due to Demodex folliculorum is an underestimated pathology which should be appropriately recognized in general medical practice.