[Seizures during interferon alpha therapy: three cases in dermatology].

BACKGROUND

Interferon alpha has many side effects. Among them the risk of occurrence of seizures is not well known by dermatologists. We report three cases of seizures that occurred in patients treated with interferon alpha in two dermatological diseases: mycosis fungoides and melanoma.

METHODS

A 68 year-old man, treated for mycosis fungoides, and two men aged 47 and 52 years, treated for melanoma, were under interferon alpha. After 11 months, 3 weeks and 9.5 months, respectively, the three patients had seizures without any past history of epilepsy. Anamnesis and assessment of each patient (brain CT, biological results) suggested the responsibility of interferon alpha. After withdrawal of the treatment, no relapse was observed after 3 months, 6 months and 1 year later, respectively.

CONCLUSIONS

Seizures during treatment with interferon alpha have already been reported. According to the series their prevalence would be of 1 to 4 p. 100. Their pathophysiology is not well known, but apparently interferon alpha lowers the epileptogenic threshold by affecting the central nervous system either directly or through cytokines or neuromediators. The risk of occurrence of seizures must be known by the prescribing physician who must systematically search for past history of epilepsy or risk factors for seizures. This rare but existing side effect raises the problem of information to be supplied to the patient by the prescribing physician.