Clinical diagnosis and management of Demodex blepharitis: the Demodex Expert Panel on Treatment and Eyelid Health (DEPTH)

Abstract

Background Twelve ocular surface disease experts convened to achieve consensus about Demodex blepharitis (DB) using a modified Delphi panel process. Methods Online surveys were administered using scaled, open-ended, true/false, and multiple-choice questions. Consensus for questions using a 1 to 9 Likert scale was predefined as median scores of 7–9 and 1–3. For other question types, consensus was achieved when 8 of 12 panellists agreed. Questions were randomized, and results of each survey informed the following survey. Results Twelve practitioners comprised the DemodexExpert Panel on Treatment and Eyelid Health (DEPTH). Following 3 surveys, experts agreed that DB is chronic (n = 11) and recurrent (n = 12) and is often misdiagnosed. Consensus was achieved regarding inflammation driving symptoms (median = 7; range 7–9), collarettes as the most common sign (n = 10) and pathognomonic for DB (median = 9; range 8–9), and itching as the most common symptom (n = 12). Panellists agreed that DB may be diagnosed based on collarettes, mites, and/or patient symptoms (n = 10) and felt that patients unresponsive to typical therapies should be evaluated for DB (n = 12). Consensus about the most effective currently available OTC treatment was not reached. Conclusions The Delphi methodology proved effective in establishing consensus about DB, including signs, symptoms, and diagnosis. Consensus was not reached about the best treatment or how to grade severity. With increased awareness, eyecare practitioners can offer DB patients better clinical outcomes. A follow-up Delphi panel is planned to obtain further consensus surrounding DB treatment.

Demodex Blepharitis: A Comprehensive Review of the Disease, Current Management, and Emerging Therapies

“…Demodex mites have been implicated in rosacea and there are close associations between Demodex skin infestation and ocular Demodex. 34,35 It is believed that once facial demodicosis develops, Demodex mites migrate and flourish around the eyes as well, contributing to ocular rosacea and/or Demodex blepharitis. Ocular rosacea is characterized by telangiectasia, lid margin irregularity, and meibomian gland dysfunction; ocular rosacea can lead to severe ocular surface disease, including cicatrizing conjunctivitis and corneal perforation.…”

“…Collarettes-solidified exudative excretions that form a cylindrical collar around the base of the eyelash follicle-are the pathognomonic sign of Demodex blepharitis. 18,21,24,35,39,[45][46][47][48][49] Several robust studies have shown that all eyes with collarettes (100%) are positive for Demodex mites, identified by microscopy 48 or by polymerase chain reaction genetic testing for the mite DNA. 12 Often referred to in the literature as cylindrical dandruff (CD), collarettes have also been called sleeves, cuffs, crusting, or lash debris.…”

“…Trichiasis, or eyelash misdirection, is common. 17,20 Madarosis, or eyelash loss, occurs in more advanced cases 20,35 and is predictive of Demodex blepharitis. Se ˛dzikowska et al 52 found a 4.30 odds ratio that patients complaining of eyelash loss would have Demodex.…”

“…Ocular itching is the symptom most commonly associated with Demodex blepharitis, 11,35,[50][51][52][53] and evidence suggests that patients consider ocular itching to be one of the most bothersome symptoms associated with the disease. 53 Demodex-related itching may be more likely to occur at night or early morning after periods of mite activity, 5,35 distinguishing it from daytime, allergy-related itching.…”

The impact of ocular demodicosis on the eyes

“…Many questions remain unanswered, including why there is poor correlation between symptoms and objective signs of DB. In this issue of Eye, experts on the Demodex Expert Panel on Treatment and Eyelid Health (DEPTH) panel attempt to achieve consensus regarding the symptoms and diagnosis of DB [9]. Consensus was reached on several points.…”