Distinguishing acute-onset CIDP from Guillain-Barré syndrome with treatment related fluctuations.

Guillain-Barré syndrome (GBS) patients may worsen after initial treatment (treatment-related fluctuation [TRF]). It is difficult to distinguish GBS-TRF from chronic inflammatory demyelinating polyneuropathy with acute onset (A-CIDP). The authors compared 13 patients with A-CIDP with 11 patients with GBS-TRF and concluded that A-CIDP should be suspected when a patient with GBS deteriorates after 9 weeks from onset or when deterioration occurs three times or more. Maintenance treatment should then be considered.