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Giant Papillary conjunctivitis has been recognized as a complication
of contact lens wear since the 1970’s. In 1974, Giant
Papillary conjunctivitis or GPC was defined as an “allergic
reaction” and is considered to be the cause of a combination
of allergic and mechanical stimuli that affected the upper tarsal
conjunctival surface in a certain group of people who wore contact
lenses. Therefore it is caused secondarily by the auto immune
reaction to the patients’ micro proteins on the lens.
Giant Papillary conjunctivitis is also known as contact lens
papillary conjunctivitis (CLPC). Its occurrence can be attributed
to all types of contact lens wear as well as ocular prosthesis,
protruding surtura after anterior segment surgery, plaques in
the cornea and tumors.
The Rate of Occurrence
The occurrence of GPC in contact lens wearers can be further
defined as generalized and local contact lens induced papillary
conjunctivitis. The incidence of GPC ranges between 2% and 18%.
In a study it has been found that in people using disposable and
frequent replacement contact lenses, 4% of that group which replaced
their contact lenses 3 weeks or less suffered from GPC whereas
36% of that group which replaced their contact lenses after 4
weeks or more suffered from this problem.
Therefore, we can come to the conclusion that prolonging the
wearing time period of disposable contact lenses directly increased
the incidence of GPC and that the problem occurs more in the case
of those using soft contact lenses. The latter point is supported
further by the data that the onset of GPC occurs approximately
within 19.86 months in case of soft lenses whereas in case of
rigid gas permeable lenses the onset averages at 21.56 months
and 90 months with hard PMMA lenses.
The Symptoms of Giant Papillary Conjunctivitis
The symptoms include discomfort while wearing contact lenses,
increased shifting of contact lenses, decreased wearing time,
itching, blurred vision and coating of the contact lens. There
may be cases where mucus discharge is present on the inner canthus
on opening the eyes. In extreme conditions patients sometimes
may have to discontinue wearing their lenses.
Observation shoes the presence of injection of the superior tarsal
conjunctiva in addition to the loss of the ability to identify
the tarsal vessel due to thickening and hyperemia of the conjunctiva.
Normal micro papillae have a diameter of less than 0.3 mm whereas
giant micro papillae have a diameter of 1 mm or more. In GPC,
the papillary reaction is usually present and the sizes of the
papules vary from .3mm to more than 1 mm. These enlarged papillae
are collections of lymphocytes and plasma cells. The papillary
reactions may be restricted to a specific area (localized) or
may spread on the total tarsal surface. These signs and symptoms
increase directly with the severity of papillary conjunctivitis.
Mast cell stabilizers may be used to reduce the symptoms but
elimination of the cause is necessary. This requires improved
lens care of the lenses more frequent lens replacement and reduced
wearing time.
The Pathophysiology of GPC
The physiological processes involving the abnormalities of GPC
is complex and it has been proved that the condition is a result
of immune mediation. The reaction is started when deposits that
are formed on the contact lenses instigate an antigen stimulus.
As a result of this tear, immunoglobulins such as IgE and IgG
are released and the complement system is activated and C3 anaphylatoxin
is formed. As this builds up an associated problem of the coating
of the contact lens leads to trauma in the conjunctiva, which
in turn releases a neutrophilic chemotatic factor that starts
the creation of inflammatory cells like lymphocytes, bosophils,
eosinophils as well as mast cells. These complement system and
tear immunoglobulins act together with the mast cells, which are
degranulated and produce a release of vasoactive amines which
manifest as inflammation, itching, mucus build up, fibrovascular
changes i.e. all the signs and symptoms of GPC.
In a study conducted on 120 subjects who used high-Dk silicone
lenses, 13 showed signs of contact lens papillary conjunctivitis.
The average onset of the disorder was about 6 months. In about
70% of the subjects the disorder was quite severe as to necessitate
the discontinuation of contact lens wear. It is found that the
initial clinical experience with high Dk - silicone contact lens
are less susceptible to coating than conventional extended wear
contact lenses. However, the silicone lenses are found to be stiffer
than the non-silicone hydrogel lenses. This stiffness of the silicone
lenses causes conjunctival trauma in some patients. Recent reports
document that generalized CPLC is more frequent in low Dk-lens
wearers whereas local CPLC is more frequent with high Dk materials.
The trauma induced GPC manifests itself in a more localized fashion.
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