Differential Diagnosis for Paraparesis

Categorization by Temporal Pattern

The American College of Neurology suggests that the rapidity of symptom onset is critical for narrowing the differential, as acute presentations suggest vascular or inflammatory causes while gradual progression indicates neoplastic or metabolic etiologies 1
Spinal cord ischemia presents with acute onset paraparesis and sensory changes, occurring in 2-6% of thoracic aortic procedures and representing the most feared complication of descending thoracic aortic repairs 1
Cerebral venous thrombosis involving the sagittal sinus can cause bilateral motor signs including paraparesis 1
Guillain-Barré syndrome progresses over days to 4 weeks with bilateral paresthesias, weakness, absent/decreased reflexes, elevated CSF protein, and electrodiagnostic evidence of neuropathy 2
Epidural abscess or hematoma presents with localized back pain, fever in only one-third of abscess cases, radiculopathy, and progressive spinal cord syndromes 3

Multiple sclerosis presents with multifocal paresthesias affecting different body regions at different times, with MRI showing periventricular white matter lesions that are sharply demarcated, round or flame-shaped, and may enhance with gadolinium 2
Lesions typically spare U-fibers initially and involve the corpus callosum, distinguishing MS from other white matter diseases 2
Lyme disease can present with encephalomyelitis showing multifocal white matter involvement, CSF lymphocytic pleocytosis, and positive two-tier serology 2

Vitamin B12 deficiency causes subacute combined degeneration with both central (myelopathic) and peripheral (neuropathic) manifestations 2

The American Academy of Neurology recommends that key features to document include temporal pattern, with acute onset suggesting vascular/inflammatory causes and gradual onset suggesting neoplastic/metabolic etiologies 1
Sharp sensory level indicates spinal cord injury requiring emergent imaging 2
Bladder/bowel dysfunction suggests cauda equina syndrome or spinal cord compression 2
MRI is the preferred imaging modality for suspected spinal pathology, even though CT may be more accessible out of hours 3
MRI with gadolinium demonstrates plaques of demyelination in MS and characterizes inflammatory lesions 2

For suspected vascular causes, complete blood count, chemistry panel, prothrombin time, activated partial thromboplastin time are recommended 1
For inflammatory/infectious causes, CSF examination is essential when distinguishing spinal cord infarction from myelitis, as CSF analysis differentiates these conditions, and CSF shows elevated protein in Guillain-Barré syndrome and lymphocytic pleocytosis in Lyme neuroborreliosis 2
For metabolic causes, thyroid function, vitamin B12, electrolytes (potassium, magnesium, phosphate, calcium) are recommended 2

Do not delay imaging if delayed recovery after neuraxial block occurs, as prompt investigation will include many patients with no pathology found, as this is necessary to identify the rare cases of epidural abscess or hematoma 3
Age-specific considerations, such as special care must be taken in patients younger than 10 or older than 59 years, those with progressive onset, and those with atypical presentations 4

The American Academy of Neurology suggests that patients with suspected Guillain-Barré syndrome should be evaluated for signs of upper motor neuron involvement, such as hyperreflexia or clonus, and that the presence of these signs may indicate a poorer prognosis 5
The presence of Babinski sign, which is a sign of upper motor neuron dysfunction, is also an important diagnostic consideration in patients with paraparesis, as it may indicate a lesion in the spinal cord or brain 5
The European Federation of Neurological Societies recommends that patients with suspected Guillain-Barré syndrome should undergo a thorough clinical evaluation, including a detailed history and physical examination, to identify any signs or symptoms that may suggest an alternative diagnosis 6
Patients with Guillain-Barré syndrome typically present with progressive weakness and areflexia, and may also experience paresthesias, pain, and autonomic dysfunction, with protein elevation in cerebrospinal fluid (CSF) without pleocytosis, as noted by the National Institute of Neurological Disorders and Stroke 5, 6

The American College of Radiology recommends that magnetic resonance imaging (MRI) of the spine be performed in patients with suspected spinal cord lesions, as it is the most sensitive and specific imaging modality for detecting spinal cord pathology 5
CSF examination is essential for distinguishing between different causes of paraparesis, such as Guillain-Barré syndrome, which typically shows elevated protein levels without pleocytosis, and other conditions such as Lyme disease, which may show pleocytosis and positive serology 6