Abstract
Ankylosing spondylitis (AS) is a chronic (progressive) painful inflammatory rheumatic disease with genetic predisposition. Genetic susceptibility and common expression cause susceptibility to other inflammatory diseases such as psoriasis, ulcerative colitis, and Crohn's disease. However, cases of motor neuron disease (MND) in patients of biologically treated patients of AS have been rarely reported. AS does not follow the same course in everyone; even among affected members of one family, the outcome varies. Here, we present a case of an unusual AS without expression of human leukocyte antigen-B27 genetic marker who subsequently develops amyotrophic lateral sclerosis the most common form of MND. This mere correlation of one noncurable disease with one potentially treatable chronic rheumatological condition adds our knowledge to existing literature.