TRACHOMA Complications & Diagnosis

Complications
The only complication of trachoma is corneal ulcer
which may occur due to rubbing by concretions, or
trichiasis with superimposed bacterial infection.

Diagnosis
A. The clinical diagnosis of trachoma is made from
its typical signs; at least two sets of signs should be
present out of the following:

1. Conjunctival follicles and papillae
2. Pannus progressive or regressive
3. Epithelial keratitis near superior limbus
4. Signs of cicatrisation or its sequelae
Clinical grading of each case should be done as
per WHO classfication into TF, TI, TS, TT or CO.

B. Laboratory diagnosis. Advanced laboratory tests
are employed for research purposes only. Laboratory
diagnosis of trachoma includes :
1. Conjunctival cytology. Giemsa stained smears
showing a predominantly polymorphonuclear
reaction with presence of plasma cells and Leber
cells is suggestive of trachoma.
2. Detection of inclusion bodies in conjunctival
smear may be possible by Giemsa stain, iodine

stain or immunofluorescent staining, specially in
cases with active trachoma.
3. Enzyme-linked immunosorbent assay (ELISA) for
chlamydial antigens.
4. Polymerase chain reaction (PCR) is also useful.
5. Isolation of chlamydia is possible by yolk-sac
inoculation method and tissue culture technique.
Standard single-passage McCoy cell culture
requires at least 3 days.
6. Serotyping of TRIC agents is done by detecting
specific antibodies using microimmunofluorescence
(micro-IF) method. Direct
monoclonal fluorescent antibody microscopy of
conjunctival smear is rapid and inexpensive.

Differential diagnosis
1. Trachoma with follicular hypertrophy must be
differentiated from acute adenoviral follicular
conjunctivitis (epidemic keratoconjunctivitis) as
follows :
 

• Distribution of follicles in trachoma is mainly on upper palpebral conjunctiva and fornix, while in EKC lower palpebral conjunctiva and fornix is predominantly involved.
• Associated signs such as papillae and pannus are characteristic of trachoma.
• In clinically indistinguishable cases, laboratory diagnosis of trachoma helps in differentiation.

2. Trachoma with predominant papillary
hypertrophy needs to be differentiated from palpebral
form of spring catarrh as follows:

• Papillae are large in size and usually there is typical cobble-stone arrangement in spring catarrh.
• pH of tears is usually alkaline in spring catarrh, while in trachoma it is acidic,
• Discharge is ropy in spring catarrh.
• In trachoma, there may be associated follicles and pannus.
• In clinically indistinguishable cases, conjunctival cytology and other laboratory tests for trachoma usually help in diagnosis.