Demodex blepharitis; Management opportunities and guidelines

MHE: How does Demodex blepharitis impact a patient’s quality of life?

Starr: Demodex blepharitis significantly impacts patients’ quality of life for several reasons. First, it has a noticeable cosmetic effect, with red, thickened and crusty eyelids, leading to self-consciousness. This condition also raises the risk of unsightly bumps on the eyelids, such as chalazia and styes, which can affect one’s appearance. Makeup wearers may experience discomfort and cosmetic challenges due to the condition.

Beyond cosmetic concerns, the physical aspects of Demodex blepharitis are equally impactful. Patients often suffer from eye irritation, persistent itching and a constant awareness of their eye discomfort, which can be distracting and affect daily life, including productivity at work.

According to the Atlas study, 47% of patients reported difficulties with night driving, and 47% were conscious of their eye issues throughout the day. Thirty-four percent had trouble wearing makeup, and 23% were concerned about the negative appearance of their eyes. Demodex blepharitis has a profound and multifaceted impact on patients’ daily quality of life.¹

MHE: Why are secondary manifestations of Demodex blepharitis a concern?

Starr: Chronic inflammation from Demodex mites can lead to persistent dry eyes and damage the eyes’ lubricating glands. This inflammation can also extend to the ocular surface, resulting in eye redness. Some evidence suggests a link between this chronic inflammation and the development of growths on the conjunctiva, such as pterygium and pinguecula.

Demodex folliculorum primarily resides in eyelash follicles, causing anterior blepharitis characterized by crusting, thickening and redness of the lid margin. On the other hand, Demodex brevis, found in meibomian glands critical for eye lubrication, can contribute to evaporative dry eye, the most common form of dry eye disease. Additionally, styes and chalazia may develop as a result.

If left undiagnosed and untreated, this condition tends to worsen over time, making it more challenging to manage at advanced stages. Prolonged undiagnosed cases lead to more common, pronounced and difficult-to-treat secondary complications, which can significantly impact a patient’s quality of life.

MHE: How does untreated disease threaten a patient’s vision?

Starr: Untreated Demodex blepharitis poses a risk to a patient’s vision, primarily through the progression of severe dry eye and ocular surface breakdown. While the likelihood of blindness from Demodex or dry eye is rare, the risk becomes more significant when the disease reaches a severe stage.

At this point, the breakdown of the corneal epithelial cells can set the stage for infection, potentially leading to corneal ulcers, thinning and, in extreme cases, perforation, which could result in permanent vision loss. Furthermore, in patients preparing for cataract surgery, a Demodex infestation of the eyelids often coincides with a higher burden of gram-positive bacteria. These bacteria are associated with post-cataract surgery infections, with endophthalmitis being the most alarming complication that can, in a substantial number of cases, lead to blindness.

Recognizing and aggressively treating Demodex blepharitis before surgery is crucial. This proactive approach can help reduce the bacterial burden on the ocular surface, decreasing the risk of post-surgery complications and potential vision damage. Therefore, addressing Demodex blepharitis preoperatively is vital to safeguard a patient’s vision and mitigate the risks associated with cataract surgery.

MHE: How does underdiagnosis of Demodex blepharitis impact patient care and outcomes?

Starr: Ocular surface disease is an umbrella term for chronic conditions affecting the ocular surface. From a clinical perspective, physicians encounter various subtypes of ocular surface diseases, including but not limited to dry eye; blepharitis; allergic conjunctivitis; rhinitis medicamentosa due to preservatives and toxic eye drops; and other factors like cosmetics, conjunctival issues and floppy eyelids. These conditions often share similar symptoms, such as eye irritation. Misclassification under a generic label like “dry eye” results in patients who return with continued discomfort. It leads to time and money wasted, causing frustration for both patients and physicians.

MHE: What can clinicians do to ensure accurate diagnosis of Demodex blepharitis and enhance patient care?

Starr: It’s essential to differentiate between subtypes of dry eye effectively. Asking targeted questions can help distinguish between eye and eyelid issues. Technicians can play a crucial role in this process, provided they are trained to ask the right questions. In the case of Demodex, patients might report itching in their eyes, even when it primarily affects the eyelids. Failure to ask these specific questions can lead to misdiagnosis. It’s important to consider these nuances when identifying ocular surface subtypes for precise treatment.

Moreover, diagnosing Demodex blepharitis has become more straightforward. The presence of collarettes, waxy cylindrical buildup at the base of eyelashes, indicates Demodex. In the past, diagnosing Demodex involved plucking eyelashes, which was inconvenient and often led to false negatives. Fortunately, studies have shown that collarettes guarantee the presence of Demodex, eliminating the need for plucking lashes or directly observing mites.

Collarettes are more prevalent on the upper eyelid, making it crucial to examine this area when assessing patients. Asking the patient to look down during the examination enhances the visibility of collarettes. When these waxy buildup structures are present, Demodex folliculorum can be diagnosed. This approach ensures a more accurate diagnosis of ocular surface subtypes and directs treatment toward reducing Demodex mites. It’s a far more effective strategy than simply recommending artificial tears, which do not address the underlying issue of Demodex blepharitis.

MHE: Demodex blepharitis often presents similarly to other ocular conditions. Can you share some examples of these overlaps, and why this might lead to misdiagnosis?

Starr: Chronic blepharitis, whether caused by Demodex or other factors, can often lead to dry eye disease over time. The key factor in this progression is the impact on the meibomian glands, which are found in the eyelids. Demodex brevis can infiltrate these meibomian glands, potentially causing blockages that lead to the development of chalazia and styes. Additionally, the presence of Demodex can disrupt the lipid layer of the tear film, accelerating tear evaporation. This rapid evaporation results in symptoms commonly associated with dry eye, such as the development of dry spots on the cornea, leading to compromised vision. Individuals experiencing dry eye often find themselves blinking frequently in an attempt to improve their vision. Therefore, when encountering patients who exhibit this behavior, it’s reasonable to consider dry eye as a potential diagnosis until proven otherwise.

Furthermore, the chronic inflammation associated with dry eye can lead to eye redness and increased inflammation, thereby perpetuating a cycle of ocular surface inflammation, tear film instability, hyperosmolarity of tears, epithelial damage and the release of inflammatory mediators. This cycle continues until it is interrupted with appropriate treatments for dry eye. If the initial cause of dry eye is Demodex blepharitis, failing to address the Demodex infestation means that the underlying initiator of ocular surface inflammation remains untreated. All these elements are interconnected within the ocular surface, a concept known as homeostasis, and maintaining this balance is the goal of many treatments.

The ocular surface is highly sensitive and tightly integrated, involving various components, from the lacrimal glands that produce aqueous tears to the meibomian glands that are responsible for lipid production. Nerves such as the seventh cranial nerve and conditions in the brain like trigeminal neuralgia are connected with the ocular surface, too. Many factors, including Demodex infestation, ocular surgeries, herpes keratitis and even preservatives in medications, can disrupt this delicate balance. In the case of Demodex, the primary disruption occurs through its effect on the meibomian glands in the eyelids, setting off a complex cascade of events that require targeted treatment.

MHE: What strategies can healthcare providers employ to improve the rate of accurate diagnosis?

Starr: When it comes to Demodex, instruct the patient to look down and check for collarettes. This quick procedure takes just a couple of seconds and should be a standard part of every eye exam, regardless of whether the patient presents with any complaints. Demodex infestation might go unmentioned, especially when the patient’s visit concerns issues like cataracts, macular degeneration or glaucoma. Even if the patient doesn’t report any related symptoms, it’s essential to incorporate this evaluation into a routine eye exam. Whenever a physician, whether an optometrist or ophthalmologist, uses a slit lamp to examine the eye, they should consistently examine the eyelashes and eyelid margin. I must admit, even I don’t perform this examination 100% of the time, especially when the patient’s primary concern is unrelated to ocular surface issues. However, I genuinely believe it should be part of the standard procedure. Even if you don’t intend to pursue aggressive Demodex treatment, it’s vital to identify it and record the findings in the patient’s chart. Perhaps you can implement straightforward approaches for managing it incidentally, even if the patient hasn’t complained about it. The rationale behind this is that all ocular surface diseases, especially in their early and asymptomatic stages, tend to progress over time. When these conditions reach more symptomatic and severe grading levels, they become more challenging and undoubtedly more costly to treat. They can also lead to more severe complications, like blindness. Therefore, it is in the best interest of eye care professionals and the broader healthcare team to diagnose these conditions in their early stages, when they are easier to manage and considerably less expensive to treat.

MHE: What are the recommended best practices for establishing a standard of care for the treatment of Demodex blepharitis, considering the absence of formal treatment guidelines?

Starr: Prior to the recent FDA approval of [lotilaner ophthalmic solution, 0.25%,] the first-ever treatment for Demodex blepharitis, there was no recognized standard of care for this condition. This lack of effective treatment often led healthcare practitioners to either avoid making the diagnosis or hesitate in discussing it with patients. It’s a rather uncomfortable conversation to inform a patient that they have mites infesting their eyelashes that crawl out at night, abrade the skin with tiny claws, lay eggs, defecate on the eyelids and contribute to crusting. Moreover, it was disheartening for both clinicians and patients to acknowledge that no effective treatment existed.

In those cases where Demodex infestation was evident, practitioners would usually recommend certain approaches. First, lid wipes were often suggested, with some studies suggesting potential benefits of tea tree oil in killing mites, although the evidence was not particularly strong. However, tea tree oil can be irritating and uncomfortable for patients.

In-office procedures such as microblepharoexfoliation were another option. These procedures, often using devices like BlephEx, mechanically debrided collarettes from the eyelids and removed biofilms. While this method could reduce mite loads, it didn’t completely eradicate them, as it primarily addressed the byproducts of the mites.

Additional suggestions included warm compresses, antibiotics (even though they were ineffective against Demodex mites) and the use of salve or ointment to potentially smother the mites by creating a barrier on the eyelashes. However, these strategies were mainly attempts to manage symptoms before the FDA’s approval of a dedicated medication.

The recent FDA-approved medication has transformed the landscape of Demodex blepharitis treatment. Clinical trials demonstrated impressive efficacy in mite eradication and removal of collarettes, making it a substantial breakthrough. With an FDA-approved solution available, clinicians can now engage in a more straightforward conversation with patients, offering an effective remedy to eliminate the mites.

MHE: Are there any drawbacks to the FDA-approved treatment for Demodex blepharitis?

Starr: The FDA-approved treatment for Demodex blepharitis was well-tolerated during the clinical trial, with no reported serious adverse effects. Cost is a consideration, but when compared to the expenses associated with various other treatment options such as wipes, procedures and ointments, the new drug’s cost appears reasonable. While it’s a relatively new medication, and I haven’t encountered patients who have completed a full six-week course, anecdotal evidence from my practice suggests no exorbitant costs reported by patients at the pharmacy. Unlike other drugs that have caused concerns due to their high prices, this new treatment seems to be more accessible. However, it’s important to note that it’s still early, and more insights may emerge over time. As of now, there don’t appear to be any significant drawbacks to this treatment.

MHE: How can clinicians help other clinicians raise awareness of Demodex blepharitis?

STARR: To raise awareness of Demodex blepharitis, clinicians can engage in various initiatives, including educational efforts like the one we’re currently involved in, which will be published for a broader audience to read. Additionally, companies developing novel treatments often take an active role in educating healthcare professionals and the public about their products. For instance, Tarsus, the company responsible for this particular medication, has been conducting webinars, publishing articles and promoting peer-to-peer discussions.

Raising awareness among patients is also crucial, especially in the ocular surface space, as conditions like Demodex and dry eye are quite common. Many individuals may be experiencing symptoms related to these conditions without realizing it. Direct-to-consumer awareness campaigns can be highly effective in educating patients. For instance, if someone is dealing with symptoms such as eyelid crusting, itching, redness, recurrent styes or dry eye, it’s essential to encourage them to seek medical attention. Many individuals may have Demodex blepharitis and not be aware of it, but knowing that there’s a straightforward treatment available — a very simple regimen and an eye drop taken twice a day for six weeks — can prompt them to take action and see their healthcare provider. Ultimately, this approach benefits everyone involved.

Reference

1. Jackson MA, Yeu E, Matossian C, Kannarr SR, Wesley G, Periman LM. Impact of Demodex blepharitis on patients: results of the Atlas trial. Abstract presented at: 2022 American Society of Cataract and Refractive Surgery Annual Meeting; April 22-26, 2022; Washington, D.C. Accessed November 30, 2023. https://ascrs.confex.com/ascrs/22am/meetingapp.cgi/Paper/81946