Ultrasound aspects in therapy-naive CIDP compared to long-term treated CIDP

To investigate the use of nerve ultrasound (NUS) along with the European Federation of Neurological Societies (EFNS) guidelines and clinical scores in untreated, recently diagnosed chronic inflammatory demyelinating polyradiculoneuropathy (CIDP) vs. long-lasting treated CIDP. NUS and nerve conduction studies (NCS) of predefined nerves/cervical roots were performed in CIDP on diagnostic onset and “chronic-CIDP” (diagnosis and therapy >6 months), compared to controls. Nerve morphology was quantified using the modified ultrasound pattern sum score mUPSS, which is the sum of 3 ultrasound scores derived at 12 predefined measurement points and the homogeneity score (HS) in ulnar, median, and tibial nerve. 21 onset-CIDP, 21 “chronic-CIDP”, and 21 age-matched controls were included. No differences in clinical scores or in the number of electrophysiologically affected nerves existed between the groups. Significantly enlarged cross-sectional areas of the nerves and diameters of the roots ensued already in onset-CIDP; however, with proximal predominance, whilst in chronic-CIDP, nerve enlargement was more prominent and ubiquitous. Increased UPS scores were shown in both patient groups compared to the controls. Significant differences between the patient groups were found particularly in the peripheral nerve score UPSA. Evaluation by means of HS revealed that the nerves in onset-CIDP were mostly regionally enlarged (often sparing distal segments) whereas in chronic-CIDP, nerves were more generalized enlarged. Onset- and chronic-CIDP show enlarged nerves and therefore increased mUPSS, however, nerve enlargement shows a more generalized pattern in chronic-CIDP compared to disease onset and correlates with disease duration and delayed therapy start, but not with disability.