Trachoma or Granular conjuctivitis or Egyptian opthalmia is a chronic keratoconjuctivitis or inflammation of cornea and conjunctiva caused by a bacterium Chlamydia trachomatis. This bacterium causes roughening of inner eye lid which causes pain in eye,breakdown of the outer surface or cornea and in severe conditions, often leads to blindness.
A. Causative Organism
Chlamydia produces inculsion bodies called as H.P. bodies (Halsberstaedter Prowazeke bodies). Till now, 11 serotypes of Chlamydia trachomatis is known (A, B, Ba, C, D, E, F, G, H, I, J & K). Serotype A, B, Ba and C are associated with hyper endemic trachoma, while serotype D-K are associated with paratrachoma.
Following is a complete list of infections caused by Chlamydia:-
B. Predisposing Factor
- Age- infants and children are more susceptible
- Sex- Females>Males
- Race- more common in Jews & less common in Negroes
- Climate- dry and dusty places
- Socioeconomic status- poor people with unhygienic living conditions
C. Source of Infection
The main source of trachoma at endemic areas is conjunctival discharge of affected person. Thus, superimposed bacterial infection helps in transmission of trachoma.
D. Modes of Infection
Infection may spread by any of the following modes:
- Direct spread of infection may occur by direct contact to infected water or air sources
- Vector transmission can be through flies
- Material such as infected tissue, towel or handkerchief can lead to spread of trachoma
- Symptoms are less if no secondary infection is there and mainly includes sensation of dust particle in eyes, sometimes leads to lacrimation, stickiness of eye lids and scanty mucoid discharge.
- If secondary infection is present, symptoms of acute mucopurulent conjuctivitis are seen.
Signs of Trachoma are seen in conjunctiva as well as cornea:-
Signs seen in Conjunctiva
- Upper tarsal and forniceal conjunctiva are congested.
- Boiled sagograin like follicles are seen on upper tarsal conjuctiva and fornix are seen which is also referred to as conjuctival follicles.
- Papillary hyperplasia is seen on tarsal conjuctiva which gives it velvety appearence.
- Conjunctival scarring develops.
- Hard looking whitish deposits of different sizes are know as concretion is found in upper palpebral conjuctiva.
Signs seen in Cornea
- Superficial keratitis in upper part of cornea.
- Herbert follicles is seen in limbal area.
- Vascularisation of cornea i.e pannus: –
- Corneal ulcer may be produced at the sites of pannus.
- Herbert pits are seen,which are circular pitted scars left after healing of herbert follicles:
- Corneal opacity may develop in upper part and may later extend to downwards involving pupillary area.
The WHO Grading System grades Trachoma into N (Normal tarsal conjunctiva), TF (Trachomatous inflammation- follicular), TI (Trachomatous inflammation- Intense), TS (Trachomatous Scarring), TT (Trachomatous Trichiasis) and lastly, CO (Corneal Opacity).
Following tests are done for diagnosis of trachoma:-
- Conjuctival cytology
- Detection of inculsion bodies
- Isolation of chlamydia
- Serotying of TRIC agents
Management of Trachoma follows Surgical, Medical and Personal management:-
Surgery is done to correct eyelid deformity which is known as trichiasis.
Medcical treatment involve commonly used antibiotics:-
- Azythromycin is a first line drug used in trachoma.(250mg od x 4 days)
- Tetracyclin is second line drug,contraindicated in children under 8 years.taken as ointment of 1% concentration for 4 times a day for 6 weeks.
- Sulfacetamide is taken as eye drops of 20% concentration 3 times a day along with tetracycline for 6 weeks.
C. Facial Cleanliness
Facial cleanliness is an important approach in prevention of trachoma and is a vital component in stopping the trachoma transmission cycle
D. Environmental Improvement
Environmental change for better sanitation and increase the access to cleaner water and air this reduces the chances of contact with the infected medium or vectors.