Table 2.

Main misdiagnosis and red flags

Misdiagnosis	Incidence, %	Misleading features	Red flags	References
CIDP	13–15	SM 4 limbs Diffuse areflexia Albuminocytologic dissociation Demyelination on biopsy Demyelinating NCS	Pain Sensory loss (wrists) Autonomic dysfunction Upper limb weakness NCS	[26] [25] [30] [31]
Chronic axonal idiopathic PN	24–33	Axonal neuropathy in the elderly, seemingly idiopathic	Severity, disability, rapid Difficulties in walking	[13] [30] [27]
CTS	11	Paresthesia in the hands	No relief after surgery	[27]
Lumbar spinal stenosis	7.3	Progressive difficulty walking in the elderly Spinal stenosis on lumbar CT or MRI	Abnormal NCS Worsening in spite of surgery	[25]
Motor neuron disease Motor neuropathy, ALS	< 1	Upper limb and tongue amyotrophy Dysarthria Hand weakness	Abnormal sensory SNAP (NCS) No symptoms of upper motor neuron involvement	[32] [29]
Miscellaneous
Alcoholic PNP		Small-fiber length-dependent PN	Alcoholism	[25]
Diabetic PNP		Small-fiber length-dependent PN Autonomic dysfunction	Rapid severity/duration of diabetes Difficulties in walking	[30]
Paraneoplastic neuropathy		Non-length-dependent sensory loss + ataxia Weight loss	No anti-onconeuronal antibody Negative findings on whole-body PET	[27]

ALS amyotrophic lateral sclerosis, CIDP chronic inflammatory demyelinating polyneuropathy, CT computed tomography, CTS carpal tunnel syndrome, MRI magnetic resonance imaging, NCS nerve conduction study, PET positron emission tomography, PN polyneuropathy, PNP peripheral neuropathy, SM sensorimotor, SNAP sensory nerve action potential