Diagnosis of Ankylosing Spondylitis: Do not let the spine bites the eye.

Background: A diagnosis of ankylosing spondylitis (AS) is challenging and often delayed despite patients being symptomatic. Low back pain is the most common initial symptom, appearing in the second and third decades of life. Acute anterior uveitis (AAU) occurs much later in the course of the disease, often when the destruction of the spine is already debilitating.