Guillain-Barré Syndrome Diagnosis and Clinical Presentation

Clinical Presentation

The American Academy of Neurology notes that Guillain-Barré syndrome is characterized by rapidly progressive bilateral weakness of the limbs, typically starting in the legs and ascending to the arms and cranial muscles, accompanied by decreased or absent reflexes and often preceded by an infection 1
Patients with Guillain-Barré syndrome often exhibit rapidly progressive bilateral weakness of legs and/or arms, typically ascending from legs to arms and cranial muscles, with decreased or absent reflexes 1, 2
Distal paresthesias or sensory loss preceding or accompanying weakness are common in patients with Guillain-Barré syndrome 2, 3
Pain, including muscular, radicular, or neuropathic pain, is frequently reported by patients with Guillain-Barré syndrome 2, 3
Dysautonomia, including blood pressure or heart rate instability, pupillary dysfunction, and bowel or bladder dysfunction, can occur in patients with Guillain-Barré syndrome 2, 3
The disease typically reaches its maximum disability within 2 weeks, with acute or subacute onset 1, 2

A history of recent infection, reported by about two-thirds of patients in the 6 weeks preceding Guillain-Barré syndrome, is an important diagnostic clue 2, 3
Neurological examination showing progressive bilateral weakness and reduced/absent reflexes is a key diagnostic feature of Guillain-Barré syndrome 1, 4
Monitoring disease progression, with maximum disability typically reached within 2 weeks, is crucial in diagnosing Guillain-Barré syndrome 2, 3
Cerebrospinal fluid analysis often reveals albumino-cytological dissociation, with elevated protein levels and normal cell count, although protein levels may be normal in some patients, especially early in the disease course 1, 4
Electrodiagnostic studies, including nerve conduction studies and electromyography, can support the diagnosis of Guillain-Barré syndrome, especially in atypical presentations, by revealing sensorimotor polyradiculoneuropathy or polyneuropathy 4
Imaging studies, such as MRI, are not part of routine evaluation but can help exclude differential diagnoses, while nerve root enhancement on gadolinium-enhanced MRI can support the diagnosis of Guillain-Barré syndrome, especially in young children 5
Antibody testing, including anti-ganglioside antibodies, may be present in a subgroup of patients with Guillain-Barré syndrome 1

The American Academy of Neurology recommends that MRI is not part of routine diagnostic evaluation for GBS, but can reveal characteristic nerve root enhancement on gadolinium-enhanced imaging, which is a sensitive but nonspecific feature that can support the diagnosis, especially in young children where clinical and electrophysiological assessment may be challenging 6, 7
MRI can be useful to exclude differential diagnoses such as brainstem infection, stroke, or other neurological conditions, particularly in young children where clinical and electrophysiological assessment can be challenging 6, 7

The primary utility of MRI in GBS is to exclude differential diagnoses rather than confirm GBS, and it is particularly helpful in distinguishing GBS from acute flaccid myelitis in children 6, 7
Differential diagnoses that can be excluded with MRI include brainstem infection or stroke, spinal cord or anterior horn cell inflammation, nerve root compression, and leptomeningeal malignancy 6, 7

The American College of Radiology recommends that spine MRI should include T1-weighted sequences with and without gadolinium enhancement, T2-weighted sequences in sagittal and axial planes, fat-suppressed T2-weighted sequences (STIR), and high-resolution steady-state or equivalent heavily T2-weighted 3D sequence 8, 9

The American Academy of Neurology notes that MRI nerve root enhancement is a sensitive supporting feature for diagnosing Guillain-Barré Syndrome (GBS), particularly valuable when clinical or electrophysiological findings are equivocal, with a sensitivity of 83-95% in typical GBS presentations 10, 11
Leptomeningeal malignancy and other inflammatory polyradiculitides can present with similar imaging findings, including cauda equina enhancement, and should be considered in the differential diagnosis 10, 11
Infectious causes can also present with cauda equina enhancement, highlighting the importance of a thorough diagnostic workup 12

The ASCO guideline for immune-related adverse events recommends MRI spine with and without contrast to evaluate for nerve root enhancement/thickening when GBS is suspected, particularly in cases with atypical features such as prominent low back pain as the initial symptom 12