Phlyctenular conjunctivitis
Ø Phlyctenular keratoconjunctivitis is characterised by nodule formation
which occur as an allergic response by the conjunctival and corneal epithelium
to some endogenous allergens which they
have become sensitized.
Aetiology:
Ø More common in females of age group 3-15 years than males.
Ø Malnutrition.
Ø Type IV hypersensitivity to microbial protein.
Ø Overcrowding.
Ø Poor hygiene.
Ø Common in spring and summer.
Pathology:
1. Stage
of nodule formation:
Ø The phlycten commences as a localised infiltration with round cells which
produces a grey nodule usually situated at limbus .The epithelium is rubbed off
and infection supervenes.
Ø The commonest organism concerned is staphylococcus .
2. Stage
of ulceration:
Ø The ulcer become s covered with polymorphnuclear leucocytes and looks
yellow.
Ø Leash of conjuctival vessels converges on ulcer.
Ø When phlycten actually starts in the cornea, the cellular
infiltration lies deep to Bowmen’s membrane as this is tightly bound and cannot
be lifted up the corneal phlycten is much less prominent than the conjuctival
or limbal one.
Ø Later bowman’s membrane and the epithelium break down to form an
ulcer.
Types
of ulcer formation:
a)
The fascicular ulcer:
Ø It starts at the limbus and creeps steadily over the cornea towards
the centre.It is followed by a leash of vessels. The head of the ulcer is the
infiltrated crescent which marks the conjunctiva. This type of ulcer do not perforate but leaves permanent
opacity.
b)
Ring ulcer:
Ø This type may break down to form
a large ulcer and perforate. Multiple small ulcers at limbus looks like grains
of sand. A ring ulcer is formed by densely packed phlycten at the limbus
breaking down and becoming confluent.
Ø The nutrition of cornea is cut off and a large perforating ulcer or
even necrosis of the whole cornea may result.
Ø Phlyctenular pannus is like trachomatous pannus but any part of the
cornea may be affected. It is thin and not very vascular.
Ø It usually go under complete
resolution with the vessels deep to bowmen’s membrane.
3. Stage
of granulation:
Ø Granulation tissue formed on healing ulcer.
4. Stage
of healing:
Ø Once granulation formation completes ulcer heals but can leave a
scar.
Clinical
presentation:
Ø Discomfort & irritation
in eye.
Ø Reflex watering.
Ø Pinkish white nodule surrounded by hyperaemia on bulbar conjunctiva
near limbus.
Ø Ocular pain.
Ø Swelling of lids and conjunctiva with redness.
Ø Foreign body sensation.
Treatment:
Ø Local antibiotic drops three times a day should be given till ulcer
heals and infection is under control. Then start local steroids ointments or
drops till ulcer subsides.
Ø Lubricating eye drops prescribed to prevent dryness of conjunctiva.
Ø If any specific focus for infection is found then it should be treated
accordingly along with improvement in general condition.
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