Effect of eye rubbing on signs and symptoms of allergic conjunctivitis in cat-sensitive individuals.
OBJECTIVE
To evaluate the effect of eye rubbing on signs and symptoms of allergic conjunctivitis in cat-sensitive individuals.


METHODS
Two prospective, nonrandomized comparative studies.


METHODS
Thirteen patients in the first study and 20 patients in the second study with a documented history of acute allergic conjunctivitis induced by exposure to cats were enrolled.


METHODS
In the first trial, all patients had one eye rubbed 15 times by the investigator without exposure to airborne allergens. Both eyes were evaluated after 5, 15, 30, and 60 minutes using subject questionnaires and slit-lamp examination. At least 1 week later, each patient was exposed to cat dander for 75 minutes; 15 minutes after entering the cat room, each patient had one eye rubbed 15 times by the examiner. Subjects' eyes were then evaluated using questionnaires and slit-lamp examination. In the second trial, the visits were identical to the first trial, except that the rubbed eye in each visit was rubbed 20 times and with more force, and that patients wore masks during exposure to cat dander.


METHODS
In both studies, the difference between patients' rubbed and nonrubbed eyes with respect to ocular itching, chemosis, and hyperemia was noted 5, 15, 30, and 60 minutes after controlled eye rubbing.


RESULTS
Without exposure to the cat room, rubbed eyes exhibited increased itching at 5 minutes in both studies and at 15 minutes in the second study (P < 0.05), increased chemosis at 5 and 15 minutes in the second study (P < 0.05), and increased hyperemia at 5 minutes in the second study (P < 0.05) compared with nonrubbed eyes. During exposure to cat dander, rubbed eyes consistently exhibited increased itching at 5, 15, and 30 minutes in the first and second study as well as at 60 minutes in the second study compared with nonrubbed eyes. Furthermore, during exposure to cat dander, rubbed eyes consistently exhibited increased chemosis at 5 and 15 minutes (P < 0.05) and increased hyperemia at 5, 15, and 30 minutes (P < 0.05) in the second study compared with nonrubbed eyes.


CONCLUSIONS
Firm eye rubbing causes a mild and transient increase in ocular itching, chemosis, and hyperemia. However, after exposure to cat allergens in cat-sensitive individuals, the effects of eye rubbing are longer and more dramatic. Eye rubbing may play a role in ocular signs and symptoms of allergic conjunctivitis in cat-sensitive individuals, especially after exposure to cat dander.
Raizman
M B
MB
New England Medical Center, Boston, Massachusetts, USA.
Rothman
J S
JS
Maroun
F
F
Rand
W M
WM
D000208:Acute Disease; D000485:Allergens / Q000009:adverse effects*; D003228:Conjunctiva / Q000098:blood supply; D003233:Conjunctivitis, Allergic / Q000175:diagnosis* / Q000209:etiology; D005123:Eye; D006023:Glycoproteins / Q000009:adverse effects*; D006801:Humans; D006940:Hyperemia / Q000209:etiology; D008405:Massage / Q000009:adverse effects; D011446:Prospective Studies; D011537:Pruritus / Q000209:etiology; D011795:Surveys and Questionnaires
D000485:Allergens; D006023:Glycoproteins; C059296:Fel d 1 protein, Felis domesticus