RS3PE presenting in a unilateral pattern: case report and review of the literature.

Objectives: To review the clinical features and pathophysiologic implications of remitting seronegative symmetrical synovitis with pitting edema (RS(3)PE) presenting in a unilateral manner.

Methods: We identified and characterized an index case of RS(3)PE presenting in a unilateral pattern. We subsequently performed a systematic literature search to identify other reports of patients with unilateral RS(3)PE.

Results: The index case was a 76-year-old male with a prior history of right hemiparesis owing to a cerebrovascular accident 25 years prior, who developed a classic picture of RS(3)PE involving hand (metacarpophalageal and wrist joint) arthritis and dorsal pitting edema, accompanied by an elevated erythrocyte sedimentation rate, but only in the nonhemiparetic hand. The condition responded rapidly to low-dose prednisone. Our literature search identified 5 other cases of unilateral RS(3)PE, including 2 presented only in the Italian or German literature. Of the 5 cases, 2 were in patients with preexisting neurologic disease, in which the neurologically affected side was spared. One additional case initially presented as unilateral disease but rapidly progressed to bilaterality. Two cases presented in a fully unilateral manner despite no reported neurologic abnormalities on the unaffected sides.

Conclusions: While RS(3)PE is almost always a symmetric disease of the upper extremities, it may rarely present in a unilateral fashion. The apparent ability of neuropathic changes to protect against the expression of RS(3)PE in an extremity suggests a role for neural and possibly other local factors in the genesis/modulation of the onset or maintenance of RS(3)PE.