This study addresses the challenging characterisation and differentiation of CIDP versus CIDP in association with Sjögren's syndrome to facilitate the process in clinical routine.
Patients with both CIDP and Sjögren's syndrome and CIDP without Sjögren's syndrome were compared concerning relevant differences in clinical, laboratory and electrophysiological findings. 154 patients who fulfilled the diagnostic EFNS/PNS criteria for CIDP were included in the analysis. 54 of these patients additionally fulfilled the ACR/EULAR classification criteria for Sjögren's syndrome.
The frequency of female patients was higher in patients with CIDP and Sjögren's syndrome (52%) versus CIDP patients without Sjögren's syndrome (28%). Furthermore, the occurrence of cranial nerve impairment was significantly higher in patients with Sjögren's syndrome (39% versus 14%). There were no significant group differences in the evaluation of initial symptoms, severity of disability judged by INCAT disability scale score, presence or distribution of sensory deficits, limb weakness and the presence of ataxia, pain or dysautonomia, CSF laboratory or electrophysiological findings.
In conclusion, our data indicate that cranial nerve impairment and female gender might represent red flags for an additional Sjögren's syndrome in patients with CIDP. The patterns of clinical disabilities and electrophysiological findings due to peripheral nerve damage are similar in both CIDP entities.