Nerve ultrasound may help predicting response to immune treatment in chronic inflammatory demyelinating polyradiculoneuropathy

Backgrounds Nerve ultrasound has been proven to be an accurate tool in diagnosing chronic inflammatory demyelinating polyradiculoneuropathy (CIDP). However, its value in guiding treatment has not been well evaluated. The aim of this study was to explore whether nerve ultrasound and its changing trend could predict the response to immune treatment in CIDP. Methods Eighty-nine therapy-naive CIDP patients were recruited prospectively and treated with steroids and/or intravenous immunoglobulin (IVIG). Ultrasonographic and electrophysiological studies were performed on the median and ulnar nerves before treatment in all patients and followed up in 45 patients. The cross-sectional area (CSA) was measured at ten sites on both the median and ulnar nerves. Results The response rate to steroids (95%) was significantly higher than that to IVIG (70%) ( P = 0.001) in patients with normal or moderately enlarged CSA, while there was no significant difference in the response rate between steroid therapy (84%) and IVIG (75%) ( P = 0.653) in patients with markedly enlarged CSA. CSAs decreased in 15 patients during follow-up, most of whom had good IVIG and steroid responses (83%) and no need for immune suppressant treatment (82%). Conclusions Nerve ultrasonography could help guide treatment strategies in patients with CIDP. Patients with normal or moderately enlarged CSA may respond better to steroids than to IVIG. The decrease in CSA after treatment may also indicate better prognosis.