Ultrasound in the Diagnosis of Chronic Inflammatory Demyelinating Polyneuropathy in Patients With Diabetic Neuropathy
Lucas Immich Gonçalves, Raed Alothman, Rodrigo Martinez‐Harms, Vera BrilABSTRACT
Introduction
The diagnosis of chronic inflammatory demyelinating polyneuropathy (CIDP) in patients with diabetic sensorimotor polyneuropathy (DSP) is challenging when both diseases coexist, as patients with DSP may have demyelinating features in nerve conduction studies (NCS). We aimed to investigate the value of nerve ultrasound (US) to differentiate patients with DSP, CIDP and DSP+CIDP.
Methods
We prospectively included adult patients diagnosed with CIDP, DSP or DSP+CIDP based on clinical assessments and NCS, who had US of the median, ulnar, fibular and tibial nerves. Patients with DSP, who presented with unexpected progression in a pattern consistent with CIDP and supportive changes in magnetic resonance imaging (MRI) or cerebrospinal fluid (CSF) analysis, were diagnosed with DSP+CIDP.
Results
Of 57 patients (20 DSP, 20 CIDP and 17 DSP+CIDP), 3 had Type1 diabetes mellitus (DM) and 34 Type2 DM. There were no differences in age, sex and neuropathy duration between the groups ( p = 0.42, 0.72 and 0.87 respectively). Patients with CIDP or DSP+CIDP had larger cross‐sectional areas (CSA) in three sites: left median at mid‐arm ( p = 0.001), right ulnar ( p = 0.002) and left ulnar ( p = 0.009) nerves at mid‐arm. There were no differences in the median CSA at the wrists ( p = 0.62), or ulnar CSA at the grooves ( p = 0.84).
Discussion
Nerve US may be helpful to differentiate patients with CIDP or CIDP+DSP from those with DSP only. Proximal upper limb nerve segments show enlarged areas in CIDP or CIDP+DSP patients.