Xerophthalmia: Causes, Symptoms, Treatment

Xerophthalmia occurs due to vitamin A deficiency. Lack of sufficient supply of vitamin A to the eyes is the primary cause of childhood blindness and treatable blindness amongst adults. This is because Vitamin A is an essential nutrient for efficiently maintaining epithelial functions.

Xerophthalmia can develop amongst males as well as females across ages. However, elderly individuals are at a higher risk of developing this health condition of the eye. In developing countries, even infants, children, and pregnant women are susceptible to this medical condition.

Xerophthalmia is a group of ocular symptoms caused due to vitamin A deficiency (VAD).

Classifications and Symptoms of Xerophthalmia

There are seven distinct classifications of VAD, each with different symptoms. Let’s take a look at each one of them here.

Night blindness

It is one of the most common symptoms of this deficiency. As evident from the name, this symptom typically occurs after dusk due to diminishing light.

It affects children, specifically between the ages of 2 to 6 years. This condition may also affect pregnant and breastfeeding women. It is difficult to understand whether a child has night blindness, unless he/she conveys about vision problems after sunset. Hence, it is important for parents and guardians to keep a close watch on any differences in the behavior of their children after the sun sets or when in a dark room.

Conjunctival xerosis

This occurs as a result of dryness of the conjunctiva. This symptom becomes more pronounced and severe when the vitamin A deficiency has been a prolonged condition due to lack of treatment. This symptom is challenging to diagnose, and hence, is often not considered one of the leading symptoms of xerophthalmia.

Bitot’s spot

This symptom manifests itself through whitish spots that are somewhat elevated, located on the conjunctiva. The white substance does not disappear even after this symptom has been successfully treated. It can be safely wiped away every time it appears.

Bitot’s spots do not always get successfully treated. This spot is most common amongst children between 3 to 6 years of age.

Corneal xerosis

Dryness of the cornea occurs as a result of a malfunction of the glands in the conjunctiva. This symptom is accompanied by loss of mucus and tears. The dryness because of the lack of these ‘wetting agents’ makes the eyes more susceptible to infection.

Corneal ulcer

If vitamin A deficiency is not treated urgently, the cornea which is the transparent protective covering on the eyes can develop ulcers.

Keratomalacia

A more severe form of corneal ulcers, keratomalacia is marked by corneal ulcers occupying a minimum of one-third of the cornea. The cornea becomes thicker and then melts away. This is the most serious form of xerophthalmia in which the cornea may get completely damaged in a few days.

Children with malnutrition are at a greater risk of developing this symptom, especially when they have a recent medical history of recurrent diarrhea or measles infection. This occurs because of vitamin A deficiency not just due to a diet that was lacking in this vitamin, but also because measles affected the vitamin A reserves in the body.

Corneal scarring

Permanent corneal scars are another acute symptom of  xerophthalmia.

Causes

The causes behind retinol deficiency can be distinctly divided into two types as below.

• Lack of sufficient dietary intake of vitamin A-rich food products.
• Inability to store vitamin A effectively and defects in metabolism due to the vitamin may result in other severe medical conditions. These health conditions include liver disorders, inflammatory bowel disease, upper gastrointestinal surgery, etc.

Risk Factors

The most common risk factors associated with vitamin A deficiency are:

• Pregnant and lactating women
• Alcohol abuse
• Impoverished populations in the developing countries
• Recent medical history of recurring bouts of diarrhoea and measles infection amongst children with malnutrition.

Diagnosis

The diagnostic procedure follows the below steps:

Physical examination and investigation of personal medical history: Diagnosis of this health condition is closely based on personal medical history, dietary history, thorough physical examination, and medical tests. The doctor closely examines the patient’s eyes for the presence of the prominent symptoms of the health condition, as discussed earlier in the article.

There are some clear indicators of the health condition that is most likely to get diagnosed on detailed investigation.

• Delayed dark adaptation of the cornea clear indicates early vitamin A deficiency.
• Dry and scaly appearance of the cells of the cornea and its degeneration may get manifested through symptoms like corneal ulcers, keratomalacia, and permanent corneal scars.
• The prevalence of Bitot’s spots become evident on the Keratinised conjunctiva at an early stage of the medical medication.

Medical tests: Your doctor is likely to recommend a diagnostic test to check for the prevalence of retinol deficiency. Normal values range from 20 to 60 micrograms per decilitre (mcg/dL). The normal values may vary slightly depending on the laboratory.

Treatment

Available xerophthalmia treatment options are:

Topical retinoic acid: Application of a topical ointment containing retinoic acid three times a day is often considered to be one of the most effective treatments for healing corneal lesions.

Vitamin A supplements: A systemic therapy comprising vitamin A supplements like a single prophylactic oral dose of retinyl palmitate may be prescribed by your doctor.

Intramuscular injection: Injections containing water-miscible retinyl palmitate might be prescribed, although it may cause side effects like vomiting.

Topical artificial tears: This may help in keeping the eyes lubricated, thus, preventing dryness.

Wrap around glasses: This prevents air from coming in contact with the cornea, preventing it from drying up.

Air humidifier: Air humidifier keeps the cornea moist, again preventing dryness.

Surgery: All symptoms of xerophthalmia, except complete corneal necrosis, may be treated through surgical therapy. There are two types of surgeries for treating retinol deficiency.

• Keratoplasty: This surgical intervention may be recommended for keratomalacia.
• Amniotic membrane transplantation: This surgery may be advised to patients with corneal perforation as a result of xerophthalmia.

Lifestyle Changes

Simple lifestyle changes in the form of dietary intake can be incorporated into your daily living  to increase intake of vitamin A.

• Incorporate animal products that are high in vitamin A. These include eggs, poultry, meat, fish liver, and dairy products.
• Carotene-rich fruits and vegetables like yellow fruits and green, leafy vegetables are rich in vitamin A. Red palm oil is also a beneficial source.
• Fortified food products like grains, sugar, and milk should also be included in the daily diet as natural sources of vitamin A.