12th August 2024

Inflammatory neuropathies

Guillain-Barré Syndrome (GBS)

GBS is an acute inflammatory polyneuropathy which causes an ascending, progressive, symmetric weakness with loss of deep tendon reflexes. Sensory involvement (commonly hand and feet paraesthesias) is generally mild. It develops acutely or subacutely with a nadir at a maximum of 4 weeks and often follows infection – C. jejuni, EBV, CMV, influenza, HIV, or COVID-19 have all been implicated. CSF is generally normal apart from elevated protein, and anti-GM1 antibodies may be found, particularly in cases associated with C. jejuni.

Treatment, as with the variants below, is with IVIG or plasma exchange. It has a 5% mortality rate and 15% are unable to walk unaided at 1 year.

Miller Fisher syndrome (MFS)

MFS is a variant of GBS with eye involvement (ophthalmoplegia), ataxia and areflexia. It is associated with GQ1b antibodies.

Acute motor axonal neuropathy (AMAN)

AMAN is an axonal variant of GBS with no sensory involvement and often more rapid progression. It is strongly associated with C.jejuni and with anti-ganglioside antibodies (GD1a, GM1).

Chronic inflammatory demyelinating polyneuropathy (CIDP)

CIDP has a similar presentation to GBS but is chronically progressive (over several months).

Multifocal motor neuropathy (MMN)

MMN, or multifocal motor neuropathy with conduction block, is characterised by asymmetric motor deficits in peripheral nerves occurring over months to years, typically affecting the hands or legs. Nerve conduction studies show conduction blocks, anti-GM1 antibodies are generally positive, and treatment is with IVIG.