Causative & risk factors
Trachoma is caused due to infection with the bacteria Chlamydia trachomatis. The infection is precipitated by unhygienic conditions such as a dry, sandy weather or flies (eye-seeking) that hover around the eyes of an infected person. Trachoma commonly affects children between ages 4-6 years and is usually seen in rural set-ups with poor sanitation and clean water scarcity. Close person to person contact especially by use of eye products from the same container can also spread the infection. It can also spread through contaminated hands, towels or articles of clothing.
Clinical presentation
Trachoma is characterized by presence of follicles on the conjunctiva and papillary hypertrophy.
The patient complains of a sensation of foreign body (grittiness) in the eye. There is excessive lachrymation and eye itching. Eyes appear congested and the patient may complain of photophobia (intolerance to light). The eyes may become painful and a discharge may be present.
Trachoma is a progressive disease. From the stage of follicular inflammation, it can progress to intense inflammation, scarring of the eyelid and ingrowing of eyelashes. Eventually the cornea becomes clouded, which can lead to corneal ulcers and eventually blindness.
Investigations
Trachoma can be diagnosed on the basis of an eye exam. Examination by a physician will detect pannus – fine sub epithelial neovascularization (new blood vessels) with infiltration of round cells. This is mainly observed in the upper part of the cornea and the upper limbus. The bulbar conjunctivae appear congested.
Treatment
In the earlier stages antibiotics are the primary mode of treatment. Advanced trachoma needs surgical to correct the inturned eyelashes away from the cornea. Corneal transplantation is recommended in patients who have severe clouding of the cornea.
Trachoma can be prevented by improving sanitation and encouraging washing of face with clean water in children.
Statistics
According to the CDC (Centers for Disease Control and prevention), globally, almost 8 million people are visually impaired by trachoma; 500 million are at risk of blindness from the disease throughout 57 endemic countries.
According to the WHO, trachoma is responsible for approximately 3% of the world’s blindness.
