SEP 11, 2019
To evaluate the utility of Lyme screening in people with uveitis, researchers performed a retrospective review of patients who were seen at the uveitis clinic at the National Eye Institute.
The cohort comprised 648 patients who were clinical research participants at the National Eye Institute uveitis clinic from 2008 through 2016. All patients had an eye exam and clinical laboratory data, including first-tier ELISA testing for Borrelia burgdorferi and second-tier testing of Western blot (Borrelia IgM/IgG). The authors reported the proportion of patients seen with actual Lyme-associated uveitis and the positive predictive value of the Lyme testing.
Among 648 patients in this study, 542 lived in areas endemic for Lyme disease. Only 27 patients had positive first tier results (4.16%); of these, only 2 (0.31% of all patients) had positive second-tier testing and confirmed Lyme-associated uveitis.
The positive predictive value of Lyme screening in this population was 7.41%, indicating that 323 patients would need to be screened to detect 1 case of Lyme uveitis. The 2 cases of Lyme-associated uveitis were patients with known tick exposures and intermediate uveitis.
The authors mention that false-positive results for initial Lyme screening had variable causes, including idiopathic uveitis and syphilis associated uveitis, and that these patients had no known risk factors for Lyme disease. Among the cases of confirmed Lyme-associated uveitis, other tests such as cerebrospinal fluid studies supported the diagnosis.
Even in areas endemic for Lyme disease, routine screening for Lyme infection as a cause of uveitis had limited usefulness in the absence of risk factors and clinical suspicion for disease.