Cutaneous reactions in patients with solitary cysticercus granuloma on phenytoin sodium

Several medical conditions are believed to be associated with an increased risk of cutaneous adverse reactions to anti-epileptic drugs. The aim of this study was to study the frequency and nature of cutaneous reactions in a cohort of patients being treated with phenytoin sodium for seizures, who were divided into those with a solitary cysticercus granuloma (SCG) and those with a condition other than SCG, to determine if the presence of SCG increases the risk of cutaneous adverse reaction to phenytoin. A cohort of 117, consecutively begun on treatment with phenytoin for seizure control, were followed up prospectively for the development of cutaneous reactions. There were 63 patients with SCG upon imaging and 54 patients to whom phenytoin was administered for seizures due to causes other than SCG or multiple neurocysticercosis. Cutaneous reactions were significantly more common (p = 0.02) in patients with SCG (9/63 patients; 14.3%) than in controls (2/54 patients; 3.7%). The spectrum of skin reactions in patients with SCG included benign skin rash (n = 3), anticonvulsant hypersensitivity syndrome (n = 4), Stevens-Johnson syndrome (n = 1), and urticaria (n = 1). Individuals with seizures due to SCG have a high incidence of cutaneous adverse reactions to phenytoin. This fact should be kept in mind when initiating them on treatment with this anti-epileptic drug.