Thalidomide and sensory neurotoxicity: a neurophysiological study.

Area of Science:

• Neurology
• Dermatology
• Pharmacology

Background:

• Thalidomide is associated with a high incidence of sensory axonal neuropathy.
• Cutaneous lupus erythematosus (CLE) is a condition treated with thalidomide.
• Understanding thalidomide's neurotoxic effects and recovery is crucial.

Purpose of the Study:

• To measure sural nerve sensory action potential (SAP) amplitude variations in CLE patients treated with thalidomide.
• To identify thalidomide's neurotoxic potential.
• To assess sensory fiber recovery after thalidomide discontinuation.

Main Methods:

• Analysis of clinical and electrophysiological data from 12 female CLE patients.
• Monitoring of sural nerve SAP amplitude during and after thalidomide treatment.
• Therapy discontinuation criteria: SAP amplitude reduction of >=40%.

Main Results:

• 11 of 12 patients showed reduced sural nerve SAP amplitude during treatment.
• 9 patients had >=50% reduction; 2 had <50% reduction.
• 5 patients reported paresthesias and leg cramps; 3 patients showed SAP amplitude recovery post-treatment.
• Median cumulative dose at neurotoxicity detection was 21.4 g, suggesting a lower neurotoxic threshold than previously reported.

Conclusions:

• Sural nerve SAP amplitude reduction is a reliable marker for sensory fiber degeneration and recovery.
• This electrophysiological parameter indicates subclinical thalidomide neurotoxicity.
• SAP amplitude changes do not predict the onset of sensory symptoms.