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Evaluation of triggers for corneal graft rejection.

BACKGROUND AND OBJECTIVE
To evaluate potential triggering factors contributing to corneal graft rejection.


PATIENTS AND METHODS
A prospective, case control study was conducted over a five month period. All patients presenting with new onset corneal graft rejection were enrolled into the study group. Two patients with clear grafts who presented shortly after each enrolled study group patient served as controls. Groups were matched for age, preoperative diagnosis, and number of previous keratoplasties. Participating patients and examining ophthalmologists filled out questionnaires regarding infectious, environmental and immunologic exposures.


RESULTS
66 patients were enrolled into the study, of which 22 had new rejection episodes. The most prevalent diagnoses were keratoconus (36.6%) and herpes simplex keratitis (22.7%). Anterior chamber reaction (77.3%) and keratic precipitates (68.2%) were the most common signs of graft rejection. A history of prior rejection episodes was significantly more frequent in the study group population (p < 0.001). Factors such as sun exposure, stress, smoking and travel were more prevalent in the rejection group but not statistically significant. The history of recent vaccinations and allergic reactions were equally prevalent in both groups.


CONCLUSIONS
The new onset of corneal graft rejection was highly associated with a prior history of graft rejection episodes (p < 0.001). Other analyzed factors were not significant triggering factors for rejection in this small series.