Unusual Parsonage-Turner syndrome with relapses and bilateral simultaneous anterior interosseous neuropathy.

We report an unusual case of Parsonage-Turner syndrome with relapses and simultaneous bilateral anterior interosseous neuropathy (AIN). A 66-year-old man, after a typical right brachial amyotrophic neuralgia few months previously, underwent surgery for left carpal tunnel syndrome. The day following surgery, wrist aching and bilateral weakness, even if prevalent on the right side, on thumb and index finger flexion appeared. Neurophysiology was consistent with bilateral AIN neuropathy and serology revealed anti-nucleus antibody positivity. Association of relapses with bilateral acute AIN involvement in the subject with autoantibody detection can suggest an immunological pathogenesis.