Demodex Outbreak Causing Palpebra Skin Lesions

Demodex spp may cause blepharitis and palpebra skin lesions. Since eyelash demodicosis seems to be quite spreadable in the community, every patient with chronic non-diagnosed blepharitis should be examined for Demodex spp. Tea tree oil treatment may be an efficient and safe therapeutical choice against ocular demodicosis.


Introduction
Demodicidae species and especially Demodex spp parasite into animal mammal follicles and may cause skin lesions to human subjects, too. The aim of the study is to report an outbreak of ocular skin (palpebra) infections due to Demodex, among community population.

Materials and Methods
The study comprised all eyelash specimens collected at the ophthalmological community wards and examined for Demodex spp.   All patients had symptoms of blepharitis, no response to treatment with antimicrobial collyria, negative ocular microbiological cultures and negative Chlamydia examinations. Palpebra skin lesions included mild edema, itch, mild or no erythema combined with intense smegma secretion from eyelash follicles ( Figure 3). Every eyelash sample included at least four eyelashes, one from each upper and lower palpebra of the patient, and was examined by optical microscope (lenses 10 × 10 and 10 × 40, total magnification x100 and x400 respectively).

Results
Within a seven-month period, 74 eyelash examinations for Demodex were registered, 28 from male (37.84%) and 46 from female subjects (62.16%). 58 samples were positive for Demodex spp (78.38% overall), 22 from male (78.57% overall men) and 36 from female subjects (78.26% overall women). Positive samples were statistically related neither to the month of sample collection nor to patients' gender (chi-square [x2] criterion). Additionally, most of the patients declared they weren't owners of mammal pets. Distribution of all demodicosis cases throughout time is shown in Figure 4. Demodex treatment has not a standardised methodology yet. Oral administration of ivermectin could be an evidence based treatment for all patients [1] but ivermectin is not practically available in Greece. Oil of Melacula tree (tea tree oil, TTO) was our final therapeutic decision due to encouraging bibliographic data [2][3][4][5] and its clinical safety [2]. In the beginning, all patients had been treated for four to six weeks by daily use of various commercial cosmetic shampoos containing TTO up to 5%. Daily TTO shampooing, for at least 5 min, included massaging and scrubbing patients' hair, head, neck and of course both eyelids and all eyelashes. Patients were advised to apply warm water or chamomile compresses onto their eyelids for 10 min just before their TTO shampooing treatment, in order to improve Demodex discard during TTO eyelid scrubbing.
Nearly half of the patients were fully relieved from Demodex after 1-1.5 month of shampooing, but the other half of them were not. These patients continued TTO shampooing and additionally underwent daily treatment with TTO 5-10%, diluted in mineral oil [2][3][4][5], depending on the patients' endurance to TTO ocular irritation. Application of TTO 5-10% was done by a cotton tip onto eyelid and eyelashes. Five to ten minutes after TTO application, eyelids and eyelashes were scrubbed for approximately 5 minutes, according to bibliography [2][3][4][5]. Patients were advised to perform TTO eye scrubbing twice a day. After four to six weeks of the combinational treatment using TTO shampoos and 5-10% TTO eyelash scrubbing, most of the patients were free of discomfort and Demodex. Patients, who still suffered from ocular discomfort and were not Demodex-free, were the ones who had poor compliance with the treatment or were forced to disrupt the treatment due to intense TTO ocular irritation.

Discussion
Observation of arachnids Demodex folliculorum and brevis in the pilosebaceous components of the eyelid of humans has been reported since 1840. In humans, demodex is also found on facial skin especially the forehead, cheeks, sides of the nose, eyelashes and external ear canals. It sometimes causes a condition called demodicosis. Demodicosis results in non-specific symptoms and signs on facial skin, mostly follicular scales, redness, sensitive skin and mild itch [6]. Demodectic frost of the ear, otitis externa, perioral dermatitis and rosacea have also been described in humans [7,8].

Conclusion
In conclusion, Demodex spp may cause palpebra infections and palpebra skin lesions. Since our study has presented eyelash demodicosis to be quite spreadable in the community, every patient with chronic non-diagnosed blepharitis should be examined for Demodex spp. Tea tree oil treatment may be an efficient and safe choice against ocular demodicosis.