see also stiff man syndrome

Acronym for Progressive Encephalomyelitis with Rigidity and Myoclonus.

Very rare. Progressive encephalopathy that affects the spinal cord and brainstem (rarely the cortex and the limbic system) with rigidity and myoclonus. Its onset is usually subacute.

Clinical presentation:

-        violent muscle spasms

-        truncal rigidity

-        reflex outbursts exaggerated by unexpected auditory or cutaneous stimuli

-        a dysautonomic syndrome: blood pressure disorders, hypersecretion.

The cause could be a decrease in the effect of glycine or GABA, inhibitory neurotransmitters, following a decrease in synthesis, a loss of receptors or an immunological phenomenon (antibodies directed against the glycine receptors).

Cause: often idiopathic but a paraneoplastic case is possible if anti-amphiphysin antibodies are found: thymoma, bronchial or breast tumour.

Treatments: high doses of GABA agonist (diazepam), repeated plasmapheresis (if autoantibodies are present), corticosteroids, cyclophosphamide.

Anesthetic implications:

patient receiving high doses of diazepam, avoid sensory stimulations, side-effects of treatment. Even if blockade of glycine receptors could possibly interfere with the action of propofol and halogenated agents, no such observations have been reported.

References : 

-        Wallet F, Didelot A, Delannoy B, Leray V, Guerin C. 
PERM syndrome sévère mimant un tétanos. 
Ann Fr Anesth Réanim 2014; 33:530-532

Updated: December 2016