Tailored solutions for diverse patients with dry eye and Demodex blepharitis

Image Credit: AdobeStock/OlegKovtun

Ben Gaddie, OD, FAAO, discussed the highlights of a recent roundtable discussion regarding 2 cases of patients with Demodex blepharitis–related ocular surface disease. He is in private practice at Gaddie Eye Centers in Louisville, Kentucky.

Gaddie explained that Demodex blepharitis plays a major role in ocular surface disease and mimics conditions that may be considered dry eye, ocular surface disease, or meibomian gland dysfunction. There is a great deal of overlap of the conditions that contribute to them.

Demodex, according to Gaddie, the most common ectoparasite found on humans, is a microorganism that is difficult to see because the parasite lives in the eyelash follicle, meibomian glands, and other facial sebaceous glands. The mite has 8 legs with claws that facilitate its movement; each claw can pierce the cellular cytoplasm, which is the main way that the mite eats. In addition, the claws cause microtrauma, possibly explaining the redness associated with blepharitis and ocular rosacea.

The mites proliferate constantly, which is why some therapies such as tea tree oil may not interfere with the reproductive cycle. New treatments work faster and facilitate curing or controlling the Demodex blepharitis.

One type of mite lives around the eyelashes and hair follicles of the adnexa (Demodex folliculorum), and collarettes, which are small, fine translucent sleeves, can be seen around those. The other type of mite (Demodex brevis) can access the sebaceous and meibomian glands. “Demodex is a component of the overall ocular surface diseases,” Gaddie said. He discussed a new drug, lotilaner 0.25% ophthalmic solution (Xdemvy; Tarsus Pharmaceuticals), that kills the mites. Findings from the FDA clinical trial showed that more than 80% of patients had fewer than 10 collarettes on their lids, he reported.

Diagnosing and treating Demodex

Gaddie advised that diagnosing Demodex requires only that the patient be instructed to look down. No microscope is needed to see the base of the lashes.

Patients take lotilaner twice daily for 6 weeks. “I instruct patients to use the entire bottle, even if it lasts beyond 6 weeks, because longer treatment is better for mite control,” he said.

Demodex case 1

A 53-year-old White woman presented with red watering eyes, which prevented her from wearing makeup. She continuously touched her eyes and face, which is symptomatic of a mite infection. The patient also complained of fluctuating vision, a hallmark of ocular surface disease.

This patient had had 3 different chalazions over the past 4 years treated with antibiotics and hot compresses. With exposure to bright sunlight, her face flushed, which occurs with ocular and facial rosacea because the skin temperature is already elevated due to rosacea.

“Two types of patients have Demodex; first are those who want or are currently wearing eyelash extensions. We observed that some patients who begin lotilaner treatment complain of eyelash loss. Demodex causes follicles to distend, and the eyelashes begin to turn and become misdirected,” he said.

Gaddie believes that the mites in the follicles are mechanically holding the eyelashes in place. When the treatment kills the mites, nothing retains the lashes and they begin to fall out. Six to 8 weeks after treatment, the lashes will begin to regrow.

The second group of patients are those who use serums for their lashes, likely because of the presence of Demodex. The eyelid margins are red, conjunctiva may or may not be involved, there are grade 3 collarettes, and there is no corneal staining.

In his practice, Gaddie first prescribes lotilaner twice daily. Tarsus Pharmaceuticals advises a 6-week treatment, but he advises applying it until the drug is gone.

For the current patient, he first performed a microblepharoexfoliation procedure to facilitate drug penetration. The patient returned after 6 weeks, when her vision was 20/20 and the number of collarettes had decreased significantly. New lash growth had begun, and she was not constantly touching her eyes.

Gaddie advised that clinicians ask patients about watering eyes, itchy eyelids, and touching the face and eyes during the follow-up evaluation. He also advised another reexamination between 3 to 6 months after treatment because of the potential for Demodex to recur. “Some patients will need treatment once annually and others twice annually,” he said.

Demodex case 2

A 66-year-old White woman presented with red, itchy eyelids and ocular dryness, and she tolerated contact lenses for only 3 to 4 hours daily. She had 50 to 100 collarettes on each lid.

She was taking cyclosporine 0.5% twice daily and using 2 lid wipes containing tea tree oil. She had also used the LipiFlow Thermal Pulsation System (Johnson & Johnson) 2 years previously. In light of these treatments, Gaddie advised clinicians to be suspicious for Demodex.

In addition to the collarettes, there was a great deal of vascularization around the lids bilaterally. Following an exfoliation procedure and treatment with lotilaner 0.25%, the patient was reexamined in 4 weeks. Her symptoms improved, she could wear contacts again, and the visual acuity was 20/20 bilaterally. However, collarettes were still present and she had persistent punctate keratitis, which eventually causes visual fluctuation, discomfort, and problems wearing contact lenses.

A reexamination 3 months later showed almost no collarettes, but there was corneal staining. After 2.5 months, the punctate keratitis persisted. Gaddie prescribed a semifluorinated alkane perfluorohexyloctane (Miebo; Bausch + Lomb) 3 times daily in both eyes. One month later, the staining was resolved in both eyes.

Current protocol

Gaddie summarized his treatment protocol, saying all 3 drugs work within 2 weeks: “If the workup shows corneal staining, my immediate go-to is perfluorohexyloctane 3 times daily in both eyes. If the workup shows cylindrical dandruff, my immediate go-to is lotilaner. If the patient [has] aqueous-deficient [dry eye], I use perfluorobutylpentanepluscyclosporine 0.1% (Vevye; Novaliq),” he said. “This protocol has worked well, without the need to look for another treatment.”