What Is allergic blepharitis?
Blepharitis, simply defined as inflammation of the eyelids, is one of the most common ocular conditions encountered by primary eye care providers and accounts for a growing percentage of primary care medical visits.
Allergic blepharitis is more commonly regarded as an allergic eye condition that involves eyelids due to sensitization to the common environmental proteins. Indeed, this diagnosis is more likely to be used by the eye doctors (pediatric ophthalmologists) who look at the specific eye parts only. If the child is seen by a pediatrician or an allergist, the eyelid allergic condition will be more likely to be viewed as the symptom of the immune allergic sensitization.
It is interesting, but specialists also disagree on the possible causes and treatments of the allergic blepharitis. More evidence of the system involvement will hopefully lead to a better clinical approach in all specialties.
Allergic blepharitis is linked to atopy by all specialists and primary care providers, which emphasizes the importance of allergy evaluation and treatment.
Blepharitis facts from different specialties
An optometrist opinion: “it is important to note that a majority of the data utilized in prevalence estimation comes from survey-based samples and may be subject to considerable overlap of conditions sharing similar presentations, including seborrheic dermatitis, rosacea, dermatitis, atopy, and dry eye syndrome (DES)”.
The pathophysiology of blepharitis is a complex interaction of various factors, including abnormal lid-margin secretions, microbial organisms, and abnormalities of the tear film. Blepharitis can present with a range of signs and symptoms, and is associated with various dermatological conditions, namely, seborrheic dermatitis, rosacea, and eczema.
We, as specialists in all types of allergy and regard entire body, find that there are two different mechanisms that can cause allergic reactivity of the eye:
- Environmental airborn allergens (pollen, cat hair, dust mites etc.)
- Contact allergens (creams, cosmetics, detergents, eye drops etc.)
Dependent on the location of contact or the immune cells involved the eye and eyelid disease names can be different. Here are some eye disease names:
- Atopic keratoconjuctivitis
- Allergic blepharoconjuctivitis
- Seasonal allergic conjunctivitis
- Contact dermatitis of the eyelid
An ophthalmologist opinion:
The classification of primary blepharitis has been used to encompass rosacea, seborrhea, and hypersensitivity caused by Staphylococcal toxins. Secondary blepharitis refers to infectious processes, bacterial or viral, or infestation by phthiriasis or Demodex. Substantial overlap of signs and symptoms exist between primary and secondary causes. As the classifications suggest, primary blepharitis tends to be a more involved etiology with a more complex presentation. Secondary blepharitis tends to be a result of a distinct disease entity rather than the cause of the blepharitis itself.
Indeed, the whole difference between these diagnoses can be mainly symptom-based:
- Eyelid allergy – blepharitis or contact dermatitis
- Inside the eye – conjunctivitis (only soft conjunctiva, but cornea is not involved),
- Keratoconjunctivitis (all eye surface, so vision suffers)
Types of allergic blepharitis
Blepharitis is commonly cataloged by eye doctors based upon anatomic location. Anterior blepharitis is defined as inflammation affecting the lash margin, involving both staphylococcal and seborrheic blepharitis; and posterior blepharitis is defined as meibomian gland involvement posterior to the lash margin.
MGD primarily affects the oil glands located on the posterior lid and therefore is included as a subset of posterior blepharitis. Angular blepharitis tends to occur in the canthal region and may present independent of anterior and posterior etiologies.
What are symptoms and signs?
As blepharitis is an inflammation of the eyelids, so the symptoms of allergic blepharitis are focused on the eye.
In addition, other signs may be present:
- Irritability and headache
- Blurry vision if the internal surface of the eyelids (conjunctiva) is involved
It is unusual to have only the eye symptoms. Most of the time the allergy affects other body organs and causes:
- Runny or congested nose
- Cough or asthma
- Postnasal drip
As we previously discussed, there are multiple causes of blepharitis, while causes of allergic blepharitis are mainly small proteins in our environment that get into a close contact with the eyelid structures and cause allergic sensitization.
When making a diagnosis, other diseases and conditions need to be ruled out. As blepharitis is mainly a symptom, it can be a part of systemic disease or any type of dermatitis.
All complications arise when the process of the allergic inflammation is left untreated, and goes beyond the eyelid surface and affects other parts of the eye:
- retinal detachment
- ophthalmic herpes simplex virus infections
- eyelashes falling out
- blurry vision
Diagnosis of the allergic blepharitis is mainly based on the symptoms. A good history with the right questions helps to establish the cause of the problem. For example:
- are the symptoms constant or appear at certain circumstances?
- Is it seasonal or year-round?
- Is there a pet in the house?
- Was there a new detergent or cream used before the symptoms started?
- Does anyone else in the house have similar symptoms?
- Did any of the measures you tried helped with symptoms?
- Is this a first time or it happened before?
After a clinical exam and discussion about environment and possible causes, an allergist will decide which tests are needed. Most common tests for the allergic blepharitis are:
- Common blood tests (total IgE, specific allergy panels can be used for screening, CBC, liver and kidney tests)
- Prick test for the allergens – environment allergens and food allergens are usually tested on different days due to cross-reactivity
- Patch test for contact sensitivity
- Avoidance test
Correct identification of the culprit will lead to the best treatment. If the environmental allergy was determined by tests, it is best to eliminate (maximum possible) an allergen from the environment and then start immunotherapy (SLIT – sublingual drops or allergy shots). Meanwhile you or your child might need an immediate relief which is a symptomatic treatment:
- Cool compress of the eyes
- Oral antihistamine
- Antihistamine eye drops
- Skin emollients (olive oil, Vaseline)
We highly discourage self-diagnosis and self-treatment. Many eye conditions look the same, and incorrect treatment can lead to complications and worsening of a problem. Eyes are very sensitive, while the allergy to one protein started the cascade reaction can lead to sensitivity to any drops or creams used at that point.
Steroids, topical or oral, can be used as the last resort when all the rest of the measures failed. Steroids, while treat the symptoms very effectively and fast have multiple serious side effects, and are not the treatment of the problem. They provide immediate relief, but after you stop them the symptoms come right back with the vengeance. Systemic steroids is a harsh consideration as they affect the hormonal balance of the body and may affect the growth of your child.
Antiinfectious agents – antibiotics, antivirals and antifungals. These should be considered if there are signs of the secondary infection, such as Herpes zoster or Staph infection. They should not be a first line of therapy.
Is it possible to prevent?
Healthy lifestyle, nutrition and proper hygiene are the best preventive measures. It is important to keep your immune system and skin in natural balance – we have amazing self-restoring quality of all mucus and skin barriers. We recommend to use only natural care of the eyes with fresh water and organic soaps (when needed). Antibacterial soaps destroy oily layers and microbiome of the skin and lead to all sorts of problems. Natural emollients and moisturizers such as organic cooking oils are hypoallergenic and will help with dryness and flakiness of the skin. Plant juices such as cucumber juice and aloe vera juice are great cleansers when needed.