Features of Xerophthalmia

Xerophthalmia is a clinical condition caused due to the deficiency of vitamin A. This condition is usually seen in infants who are weaned off from substances rich in vitamin A and in those children who eat very less vegetables. Peak incidence is seen in 2-5 years of age group.

The condition is also seen in other eye infections such as trachoma, burns, rheumatoid arthritis, intake of certain drugs such as beta-blockers and some cases are idiopathic also.

Symptoms

In this, the conjunctiva becomes dry and lusterless. Early symptoms include night blindness and dry conjunctiva. The cornea becomes unwettable and opaque (as the transparency gets lost). In severe cases, corneal ulceration and perforation may also occur.

On examination, small plaques called Bitot’s spots appear, which are grey in colour. These spots disappear on administration of vitamin A doses. Though, these spots can also be seen in healthy individuals.

Stages

Primary stages

Initial occurrence of conjunctival xerosis is followed by appearance of Bitot’s spots which the leads to corneal xerosis. Till this stage, the condition is completely reversible. After this, corneal ulceration occurs followed by the last stage called keratomalacia, in which there is excessive softening of the cornea.

Secondary signs

These include night blindness followed by dryness of conjunctiva and later of cornea. Photophobia also develops and sometimes lusterless hair and dry mouth may also occur.

Clinical Examination

The clinical staging symptoms almost confirm the diagnosis. However, the most widely used clinical technique is to detect the Tear film break up time (BUT). It is the interval between a complete blink of eye and the appearance of first dry spot on the cornea. The normal time limit is 15-30 seconds. If the value comes out to be less than 10 seconds, it indicates high deficiency.

Other tests done are Schirmer 1 test, Rose bengal staining and tear osmolality test. Scraping from the Bitot’s spot shows the presence of xerosis bacteria.

Treatment

Vitamin A doses are given to correct the deficiency. Antibiotic ointments are also prescribed to control the secondary infection. Tear substitutes are also helpful.

Advice

The patients must take a lot of dark green leafy vegetables and milk. The things to avoid include heat, wind and strong light.