Demodex blepharokeratoconjunctivitis affecting young patients: A case series

Abstract

Purpose: To report clinical characteristics of Demodex blepharokeratoconjunctivitis affecting young patients.

Methods: This is a retrospective review of 14 patients with the history of chronic red eyes with corneal involvement. All patients were diagnosed with ocular demodicosis based on the results of eyelash sampling. All patients were treated with 50% tea tree oil lid scrubs and two doses of oral ivermectin (200 mcg/kg).

Results: The median age of patients at diagnosis was 27 years (range: 11-39 years). The duration of symptoms ranged from 2 months to 20 years. Rosacea was present in only three patients. Four patients had best corrected visual acuity less than 20/60. Allergic conjunctivitis (n = 7) and viral keratitis (n = 5) were the most common misdiagnosis previously made. Cylindrical dandruff was present in only six patients and eyelashes were clean in rest of them. Inferior vascularization was present in eight eyes, superior in seven eyes, and corneal scars were present in 12 eyes. Four patients had steroid-related complications. All patients, except one responded to tea tree oil treatment and 13 patients were off steroids after 3 weeks of starting the treatment.

Conclusion: Demodex infestation of eyelids can lead to chronic blepharokeratoconjunctivitis in healthy pediatric and young adult patients who otherwise have good hygiene, which can often be overlooked or misdiagnosed. Viral keratitis and allergic conjunctivitis are common misdiagnoses and demodicosis can be confirmed by simple epilation. Early diagnosis and treatment can prevent long-term steroid use and its related complications.

Keywords: Blepharokeratoconjunctivitis; Demodex; chronic red eye; misdiagnosis; tea tree oil.

Figure 1

Photographs with different corneal findings. Presence of either inferior, superior or all-around corneal vascularisation( a-l); active infiltrates(a, b, j, k) or scars (c, d , h , i, l); phlycten (b) and peripheral ulcerative keratitis (g)

Figure 2

Patient misdiagnosed as a case of phlyctenular conjunctivitis. Patient had phlycten-like nodule at 9 o'clock (arrow in a) and florid inferior vascularization (a) with diffuse cylindrical dandruff (b). Treatment with tea tree oil lid scrubs and oral ivermectin resulted in resolution of phlycten (arrow in c) and regression of vascularization. Eyelashes also showed improvement (d)

Figure 3

Representative case 3. Right eye (a) showing diffuse conjunctival inflammation and corneal scars. With 10 years history of multiple misdiagnosis and treatments, eyelashes were clean (b), without any cylindrical dandruff. Tea tree oil therapy resulted in significant reduction in conjunctival inflammation (c)