Uveitis does not have to be vexing. Here are some basic principles to make it easier for ophthalmologists to identify the disorder.
DEFINE UVEITIS CHARACTERISTICS
A project called the Standardization of Uveitis Nomenclature (SUN) has attempted to better define uveitis characteristics. Dr. Dunn reviewed various findings from the SUN criteria to assist in creating a more precise differential diagnosis.2 First, consider the disease history, onset, and duration (such as whether it has been present in a patient for under 3 months or for 3 months or more).
Also, consider if the patient has a sudden onset flareup with limited duration; recurrent disease, defined as occurring more than 3 months after stopping therapy; or chronic uveitis (lasting more than three months or requiring ongoing suppressive therapy for more than three months).
“Laterality is also important,” Dr. Dunn said. “It could be unilateral, unilateral and alternating, bilateral simultaneous, or bilateral and asynchronous.”
Anatomic location—including anterior, intermediate, posterior, or panuveitis—is another key indicator. However, the presence of certain structural complications—such as macular edema—does not in and of itself define that area of the eye as being involved, Dr. Dunn said. For example, iridocyclitis with macular edema is classified as anterior uveitis, not panuveitis. The presence of cell or flare is another finding to consider.
“However, cell is not the same as flare,” he said. “Some diseases have more cell, and some have more flare.”
Take some time to characterize the hypopyon— its color, size, and whether it shifts with change in head position, as may occur in Behcet’s disease Also, consider keratic precipitates (KP) and whether they are granulomatous or non-granulomatous, Dr. Dunn said.
Remember that granulomatous diseases (such as sarcoidosis) may present with non-granulomatous KP, but non-granulomatous diseases (such as HLA B27-associated uveitis) almost never present with granulomatous features. If a patient has posterior uveitis, try to define if it is retinitis, choroiditis, retinal vasculitis (such as arterial or venous), or a combination. For any lesions that are present, make note of their size, shape, and colo —all of which can be important for diagnostic purposes.
1. Jabs DA, Busingye J. Approach to the diagnosis of the uveitides. Am J Ophthalmol. 2013;156:228-236.
2. Jabs DA, et al. Standardization of uveitis nomenclature for reporting clinical data. Results of the First International Workshop. Am J Ophthalmol. 2005;140:509-516.