January 17, 2012
Test for inflammatory dry eye disease
The nonspecific inflammatory marker matrix metalloproteinase 9 (MMP-9) has consistently been shown to be elevated in the tears of patients with DED. MMP-9 plays a critical role in wound healing and inflammation.4,5
It is primarily responsible for the pathologic alterations to the ocular surface that lead to a dysfunctional tear film.4,6
MMP-9 activity is significantly elevated, even in mild DED, and may be a more sensitive diagnostic marker than clinical signs. Furthermore, the level of MMP-9 in tears correlates with the clinical severity of the disease.7 InflammaDry (Rapid Pathogen Screening Inc.)
is a new, in-office immunoassay that detects elevated MMP-9 in tears in 10 minutes (Figure). This test is currently under FDA 510(k) review but is available outside the United States. Identifying patients with inflammatory dry eye is the first step to better perioperative management of the ocular surface. Source
In DED, the eye can be white and quiet despite an inflamed tear film. Elevated levels of MMP-9, especially in the setting of artificial tears’ not being effective, confirms the diagnosis of DED and should trigger the use of antiinflammatory therapies such as cyclosporine. [Source]
A negative InflammaDry test suggests a noninflammatory cause of DED.