Non-specific Symptoms Associated With Demodex Blepharitis Often Lead to Misdiagnosis
Symptoms non-unique to DB, such as itching and scratching, may lead to misdiagnosis.
Christopher Starr, M.D., FACS: The symptoms of Demodex blepharitis overlap with all of the other ocular surface diseases. This was also something that we tackled in this algorithm that we created for managing ocular surface disease in the context of the presurgical patient. But the algorithm, the diagnostic and management algorithm for ocular surface disease in the presurgical patient certainly pertains to all patients, whether they’re having surgery or not. One of the things that we know when it comes to ocular surface disease, and this is what has led a lot of not only doctors but also patients to be kind of frustrated with this area, is that the symptoms are very overlapping. Patients with blepharitis will probably have a lot of the same symptoms as a dry eye patient, as the person with exposure keratitis, as a person with allergic conjunctivitis or infectious conjunctivitis, and so on and so forth. There are many of ocular surface disease subtypes, but they all have very similar symptoms. Over the years and even continuing to this day, when these patients come in with these symptoms — dryness, itchiness, redness, my eyes are itchy, they’re gritty, they get a foreign body sensation, my vision fluctuates — those symptoms can be attributable to virtually any of the ocular surface diseases. But a lot of practitioners will just say you have dry eye so go take some artificial tears and you’ll be fine and sort of sweep it under the rug. The patient goes and takes the artificial tears, and they are still suffering, and they come back and say, well, my eye is still red. Well, you know, take more artificial tears. Then the patient goes and sees someone else, and so it’s this vicious circle of ocular surface diseases, misdiagnosis and mismanagement.
What I think we need to do better is isolate the symptoms and try to pin each symptom to an actual diagnosis. The best way to do that is certainly with a very careful and thoughtful examination. Itching is something that we hear a lot. Many doctors will sometimes just say dry eye [disease], but a lot of times then they’ll jump to maybe it’s allergy. Let’s treat allergy, let’s do antihistamine eyedrops and oral allergy medication. And then, of course, the patients who have itching because it’s actually from Demodex and it’s actually their (eyelid) margin that’s itchy and not necessarily their eyes or it’s both, will also be misdiagnosed and mistreated, and they’ll still be suffering. Their eyelids will still be itchy, and they’ll come back and say, my eyes are still itchy, and they’ll get the same treatment and so on and so forth, and then they will go find other doctors.
(My approach often is,) is it your eyes that are itchy or is it your eyelids that are itchy? Show me how you (rub) your eyes when they get itchy, and when somebody does this, it’s probably allergy. But when somebody takes their finger down and goes across their eyelashes like this, that to me is eyelid itching. And that is very characteristic. That kind of scratching with the fingernail on the lashes (demonstrates) it’s not part of the pathognomonic of Demodex blepharitis, but in my experience, it’s almost assuredly related to anterior blepharitis an,d in most cases, that’s going to be Demodex. I think that that’s a great little pearl for all practitioners…and patients, too. I think that these educational little pearls are good for both doctors and patients. Patients may say hey, I do that. Oh, maybe I should go get checked out. There was a study called the Titan study that just came out, which looked at 1,000 patients and 58% of patients who came to an eye clinic had Demodex blepharitis, which is an astonishingly high number. And 69% of patients who had been diagnosed with blepharitis had Demodex blepharitis. So it’s extremely common. We really need to be looking out for it and recognizing not only the symptoms but the flow and signs as well.
When you’re seeing 50, 60, 70 patients a day, you have very limited time. A lot of doctors will just kind of recoil at anything that’s ocular surface-related. They won’t take that extra 5 seconds and ask a couple of pointed little questions about the symptoms or the way they itch or the signs. And that’s all it takes. This is not rocket science. This is fairly straightforward, simple stuff, but it requires just a little tiny bit of extra probing. But then you’re a hero if you make the diagnosis, and the patients will forever be indebted and grateful and happy that they finally got the right treatment that they needed.
Transcript is AI generated and reviewed by MHE staff.
