Friday, February 15, 2013

Allergic Eye Disease


Allergic Eye disease


 

The prevalence of eye diseases in urban areas is increasing day by day and constitutes about 20% to 40 % in the children below 12 years.

A large number of different types of allergens are present in our environment like pollen, mould, spores, dust mites, animal dander and air pollutants from factories and vehicles. The studies conducted in different areas with different levels of air pollution has presented with very interesting revelations. The modern type 2  air pollutants like NO2 , Ozone, VOCS ( volatile organic substances), tobacco smoke, diesel emission particles, fine and ultra-fine particles were found to adsorb to airborne particles and they in turn attach to pollen surfaces and increase the release of allergenic proteins. It was found that pollens collected at the road-side which had pollutants attached to them were potentially more allergenic than those collected from rural meadows.

Environmental tobacco smoke exacerbates allergic diseases in children. Passive smoking during pregnancy or lactation was found to be a risk factor for respiratory ailments like asthma and allergic diseases in the offspring.

Allergic contact eczema

This is caused by the direct contact of the allergens to the skin of the eyelids or that around the eyes. The allergens include:-

Eye cosmetics

Contact lenses

Allergen contaminated pillow, like with hair dye of other person

Nail varnish

Drugs used for medicinal purpose like neomycin, gentamycin etc

Sun exposure (Photo contact allergy)

Preservatives in eye drops

Metals like nickel (may be contained in spectacle frames and eye lash curlers)

Rubber eyelash curlers or swimming goggles.

Plant products like grape seeds, grape fruit seeds, green tea, ginger, sunflower, wheat sage, oatmeal, ginseng, cocoa butter… and many more..

Erythematous and itching, well circumscribed macules with scales are the main presentation of this disorder.

Atopic eczema

It is the inflammatory, chronically relapsing, itching skin disease with typical age-related distribution of lesions. Most of the cases start below 5 years of age. It causes eyelid eczema and also itching of the eyes and eye lid skin and many times associated with allergic rhinitis (sneezing and running nose) and the dark discolouration around the eyes.

 


Allergic conjunctivitis

Seasonal allergic conjunctivitis

Symptoms are itching, redness, lid swelling and stringy mucoid discharge of the eyes. Mostly occurs during specific seasons especially spring or autumn.


Perennial allergic conjunctivitis

It is also associated with itching of eyes, redness, swelling of lids and stringy discharge but it occurs throughout the year but may have remissions and exacerbations. The common causative factors are dust mites and cat or animal dander that is present throughout the year.
 

Vernal conjunctivitis

It starts in children of as small as 2 to 4 years and is associated with itching and redness that is typically pink in colour. The children rub their eyes intensely and also there is increased blinking and also stringy, ropy discharge. This if left untreated can cause ulcers of the cornea called as shield ulcers. This type of allergy occurs in children mostly in spring and so it is also called as spring catarrh. It usually dis appears after teen age but treatment is necessary till that age.

Atopic kerato-conjunctivitis

It is associated with allergic asthma or allergic rhinitis (running nose and sneezing) 87% of the times. It starts in teens or early 20s and may persist for decades.  The skin of the eyelids and around is frequently involved. The symptoms in eyes include intense itching, tearing and light sensitivity (photophobia) due to corneal involvement, redness of eyes, blurred vision, and stringy discharge. If left untreated it can cause scarring of the eyelids, the openings of the lacrimal apparatus called as puncta present at the corner of the eyes which drain the tears and also the conjunctiva causing stem cell deficiency.

Prevention and Treatment: - It is very challenging to treat allergies as the allergens are very difficult to pin point in each individual and their presence cannot be completely discarded from the environment. Glares are a must while driving and protective glasses while working in polluted environment. Cleaning of eyes with regular tap water after coming home from work is also useful. Washing of hands after handling medicines or cosmetics prevents them from reaching eyes due to contact.

Allergies are treated with anti-histaminic drops, decongestant drops or steroids. Now, a large choice of medicines are available that can be prescribed according to specifications of signs and symptoms. The most important part is that when allergy is intense and chronic, steroids have to be prescribed, which can cause side effects like raised eye pressure and cataract if used for prolonged periods, but now steroid preparations which have fewer side effects, are available which are of immense help.

Also when there is conjunctival scarring due to chronic allergy, stem cell transplants are a hope to the patients.  

 

 

 

    

 

 

 

   

 

Tuesday, February 5, 2013

Redness of Eyes


 Redness of eyes could be a sign of a very simple  ailment of the eye or signal some serious eye problem. Red eyes caused by anger are not the scope of this article, but all other causes are!

Redness of eyes can be caused by

1)      Inflammation of the conjunctiva (the transparent layer covering the white part of the eye) due to-

a)Infection due to bacteria, viruses, and other microscopic organisms

b) Allergies due to dust, pollens, cosmetics and many other particles in the air. Allergies can be seasonal or can occur throughout the year.

A specific type of allergy affects children from a very early age, sometimes from 2 years of age. It is called as ‘spring catarrh’. This allergy occurs at every season change or in spring and is associated with itchy red eyes. It reduces as the child grows and mostly goes off after 16 to 17 years of age. But it requires medication and control till it is resolved.

2)      Infection of the eyelids called as blepharitis which is associated with flaking and matting of the eyelids at the roots of eyelashes. It also causes redness of eyes.

3)      Uveitis means the swelling and inflammation of brown pigmented middle layer of the eye that can be seen as iris from outside. It can be autoimmune (the immune system that counters the infections and allergies that occur from outside the body starts attacking the parts of the body itself) or caused by certain diseases like tuberculosis or syphilis or herpes infections.

4)      Dry eye which is cause by reduced tear secretion of the eyes, mostly in the elderly and in post – menopausal women. It can also occur in reduced secretion of oil by the glands of the eye which causes evaporation of the tears due to reduced oil (meibum) by the glands when it is called as evaporative dry eye. This can also be caused by long hours on computers. 

5)      Sub-conjunctival hemorrhage causes frightening dark red localized fleshy redness of the conjunctiva and can be caused by very simple acts like coughing, sneezing, straining at stools, lifting heavy weights, but can also be caused by reduced clotting of blood in some blood dyscrasias(where there is deficiency of the clotting factors in the blood or abnormal blood cells) and also in hypertensive patients. When it is due to commonplace reasons patients can be told to relax and not be afraid as it reduces on its own after about two weeks.

6)      Foreign body anywhere in the eye like dust particles during driving, glass or iron particles in factory workers. And also acid and alkali burns due to everyday use chemicals like toilet cleaners, mosquito repellents and many others. It is very important that patients are instructed to thoroughly wash their eyes even before they come to the eye clinic as earlier the eyes are washed the better.

7)      Ulcers of the cornea due to infections from bacteria and viruses  (herpes corneal ulcer is the commonest) and also fungi which occurs mostly due to injury with a tree branch, rice husk, blades of grass or foreign bodies of vegetative origin especially in rural areas  going in the eye.

8)      Contact lens over-wear or unhygienic use of contact lenses. We advise all contact lens wearers to wash their hands before handling the lenses and to replace the lens solution regularly and clean the lenses while putting them on and removing them every day.

9)      Acute congestive glaucoma which occurs more frequently as the age advances and is caused by raised eye pressure and is associated with severe eye pain.

                          The treatment of the redness of the eyes varies according to the cause but it is always advisable to seek opinion from Medical practitioners and not buy medicines from over the counter as they have potential side effects. The most over used preparations are the corticosteroids and they have severe side effects like raising eye pressure, to causing early cataracts. Inadvertent use of antibiotics causes the organisms to become resistant and the antibiotics to be ineffective and so great care has to be taken while using them.