The Significance of Serum Anti-Borrelia Antibodies in the Diagnostic Work-Up of Uveitis

Diagnosis of Lyme-associated uveitis: value of serological testing in a tertiary centre

AIMS

To determine the frequency and clinical presentation of Lyme disease in patients with uveitis and to assess the value of Borrelia burgdorferi serological testing.

METHODS

Retrospective study on all patients with uveitis who were referred to our tertiary hospital were serologically tested for Lyme in our laboratory between 2003 and 2016. Screening consisted of determining B. burgdorferi serum IgG and IgM by ELISA method. The patient's serology was considered as positive if the ELISA-positive result in IgM and/or IgG was confirmed by an immunoblot positive in IgM and/or IgG. Lyme-associated uveitis was diagnosed based on serological results as well as response to antibiotics and exclusion of other diagnosis.

RESULTS

Of the 430 patients with uveitis (60% women, mean age 49 years) fulfilling inclusion criteria, 63 (14.7%) had an ELISA-positive serology, confirmed by immunoblot for 34 patients (7.9%). The diagnosis of Lyme-associated uveitis was finally retained in seven patients (1.6%). These patients reported either a previous exposure including tick bite or forest walks (n=5), symptoms suggestive of Lyme disease (n=5) and resistance to local and/or systemic steroids (n=7). Among the remaining 27 positive patients, 22 had other established aetiologies and 5 other were unclassified.

CONCLUSION

The seroprevalence of B. burgdorferi among our patients with uveitis was 7.9% compared with 6 to 8.5% in the general French population which leads to a low predictive value of serological testing. Its use should be reserved for patients with unexplained uveitis, an exposure history, systemic findings suggestive of Lyme disease and steroids resistance.

Poor Positive Predictive Value of Lyme Disease Serologic Testing in an Area of Low Disease Incidence

BACKGROUND

Lyme disease is diagnosed by 2-tiered serologic testing in patients with a compatible clinical illness, but the significance of positive test results in low-prevalence regions has not been investigated.

METHODS

We reviewed the medical records of patients who tested positive for Lyme disease with standardized 2-tiered serologic testing between 2005 and 2010 at a single hospital system in a region with little endemic Lyme disease. Based on clinical findings, we calculated the positive predictive value of Lyme disease serology. Next, we reviewed the outcome of serologic testing in patients with select clinical syndromes compatible with disseminated Lyme disease (arthritis, cranial neuropathy, or meningitis).

RESULTS

During the 6-year study period 4723 patients were tested for Lyme disease, but only 76 (1.6%) had positive results by established laboratory criteria. Among 70 seropositive patients whose medical records were available for review, 12 (17%; 95% confidence interval, 9%-28%) were found to have Lyme disease (6 with documented travel to endemic regions). During the same time period, 297 patients with a clinical illness compatible with disseminated Lyme disease underwent 2-tiered serologic testing. Six of them (2%; 95% confidence interval, 0.7%-4.3%) were seropositive, 3 with documented travel and 1 who had an alternative diagnosis that explained the clinical findings.

CONCLUSIONS

In this low-prevalence cohort, fewer than 20% of positive Lyme disease tests are obtained from patients with clinically likely Lyme disease. Positive Lyme disease test results may have little diagnostic value in this setting.

La maladie de Lyme du point de vue de l’ophtalmologue

The first case of Lyme disease was described more than 25 years ago in the city of Lyme, Connecticut (USA) and although the responsible pathogenic organism is known (Borrelia Burgdorferi) as well as its vector (a tick from the Ixode genus), it is still underdiagnosed and often poorly known by practitioners. The symptomatology is classically divided into three phases depending on the time between the tick bite and the first symptoms. However, in a number of cases this clinical division of the disease is not easily applied. We describe three cases of atypical ocular manifestations to illustrate this problem. Recently developed laboratory tests help confirm the diagnosis but should not be used without a good knowledge of the disease. This study aims to emphasize the difficulty of diagnosis and the importance of appropriate treatment and to avoid potentially permanent complications.