Guillain-Barré syndrome laboratory tests


 * Associate Editors-In-Chief: Priyamvada Singh, MBBS [mailto:psingh@perfuse.org]

Overview
Guillain-Barré syndrome (GBS) is usually diagnosed clinically. Lab tests are done to exclude other diagnosis and assess prognosis. The lab tests ordered are basic labs (CBC, ESR), lumbar puncture (GBS has characteristic albuminocytological dissociation), serological markers

Routine labs

 * Complete blood count + ESR (increased in inflammatory process)
 * Serum electrolytes
 * Liver function test
 * Creatinine kinase increased in inflammation and myopathies
 * Stool culture for campylobacter jejuni (less frequent)

Cerebrospinal analysis

 * CSF is used almost every time to verify symptoms, but because of the acute nature of the disease, they may not become abnormal until after the first week of onset of signs and symptoms.
 * Typical CSF findings include an elevated protein level (100 - 1000 mg/dL) without an accompanying pleocytosis (increased cell count) (albuminocytological dissociation in the CSF). A sustained pleocytosis may indicate an alternative diagnosis such as infection
 * On contrary Guillian Barre syndrome in HIV patients have CSF pleocytosis
 * In 1 in 10 patients with GBS, the CSF protein may not be elevated.

Serology

 * Less frequently done for campylobacter jejuni, CMV, EBV, HSV, HIV and mycoplasma pneumonia.
 * Autoantibodies are only measured in case the diagnosis of GBS is uncertain. Antibodies to glycolipids, anti GM1 antibodies and Anti-GQ1b are increased.

Peripheral neuropathy panel
A panel of tests can be ordered in cases of diagnostic uncertainty with other peripheral neuropathies
 * Vitamin B12, folic acid


 * Thyroid profile (to rule out thyroid neuropathies)


 * Erythrocyte sedimentation rate (ESR)increased in inflammatory process


 * Rapid protein reagent for syphilis


 * Rheumatology profiles


 * Hemoglobin A1c for diabetic neuropathy


 * Immunoelectrophoresis for serum protein (multiple myeloma)


 * Heavy metal poisoning