Spinal Stenosis with Sacral Osseous Deformity Mimicking Chronic Inflammatory Demyelinating Polyneuropathy

Abstract

BACKGROUND: Differential diagnoses of neurosurgical spinal disorders and polyneuropathies have been recognized to cause clinical perplexity, occasionally misdiagnosing chronic inflammatory demyelinating polyneuropathy (CIDP). When nerve conduction studies and cerebrospinal fluid (CSF) analyses reinforce a certain clinical presentation, the importance of imaging studies, conservative treatment response, and interdisciplinary clinical approach should be highly emphasized. CASE PRESENTATION: We report a 51-year-old patient who presented with a 16-week history of neurogenic claudication and right-sided lower extremity monoparesis, with low back pain syndrome dating from 10 years ago. He was initially evaluated by a neurologist under the suspicion of CIDP, supported by nerve conduction studies and CSF analyses, without any subjective or objective improvements after systemic corticosteroid therapy. After performing magnetic resonance imaging (MRI) of the lumbosacral spine, he was referred to a neurosurgeon. Neurological examination revealed features of lower motor neuron lesion, consistent with the MRI findings of L4-L5 and L5-S1 stenosis with right-sided S1 vertebra osseous deformity, without any radiographic evidence of CIDP. The patient underwent surgery and improvements were noted early in the post-operative recovery phase and continuously throughout the regular monthly follow-ups, without any clinical features of CIDP. Histopathology results confirm sacral osseous deformity. No evidence of CIDP, osseous deformity residue, or recurrence was evident on the post-operative MRI control performed 11-month post-surgery. CONCLUSIONS: Degenerative spinal stenosis compromising spinal canal dimensions can mimic CIDP due to sharing multiple clinical similarities. That scenario is especially highlighted when age-related spinal degenerative disease is unexpected and seldom aggravated by spinal osseous lesions. Avoiding misdiagnosis and providing adequate treatment can pose a serious challenge for neurosurgeons and neurologists, demonstrating the importance of an interdisciplinary approach toward diverse spinal disorders.