Orbital myositis associated with Borrelia burgdorferi (Lyme disease) infection

To report on the clinical findings in a patient with isolated left inferior rectus myositis associated with serologically confirmed Borrelia burgdorferi infection. Interventional case report. Comprehensive clinical, laboratory, and imaging evaluation. Contrast-enhanced computed tomography showed a swollen inferior rectus muscle with infraorbital soft tissue swelling in a patient with diplopia and prior symptoms consistent with manifestations of Lyme disease. Positive serum and cerebrospinal fluid antibodies to B. burgdorferi by enzyme-linked immunoassay were confirmed by Western blot, and the cerebrospinal fluid/serum antibody ratio was elevated. No alternative cause for orbital myositis was found, and treatment with antibiotics resulted in a complete recovery. Orbital myositis should be added to the expanding list of ophthalmic manifestations of Lyme disease. Correct diagnosis and appropriate antibiotic therapy may reduce the likelihood of further neurologic or ophthalmologic sequelae.