Gastrointestinal and Urologic Sphincter Dysfunction in Stiff Person Syndrome

Stiff person syndrome is a neurologic disorder characterized by axial rigidity leading to progressive disability, with broad clinical spectrum.

We report 2 cases with unique clinical presentation.

Two young men suffered progressive urinary retention requiring bladder catheterization, anorectal spasms and constipation, complicated subsequently with lower extremity trigger-induced spasms, and gait instability. Associated symptoms revealed brainstem involvement (vertigo, diplopia, and cranial neuropathies) and dysautonomia (abnormal sweating and orthostatic hypotension). Anal manometry demonstrated incomplete relaxation of the anal sphincter. The first case was associated with diabetes mellitus type I, did not respond to classical therapies, but was responsive to rituximab. The second case responded to intravenous immunoglobulin infusions. Paraneoplastic profiles were negative, and anti-GAD65 antibody titers remained elevated despite successful therapeutic responses.

We want to raise awareness that stiff person syndrome can present with esophageal, anorectal, and urethral sphincter disturbance. Rituximab is a good therapeutic option in intractable cases.