1 - Serviço de Imunoalergologia, Centro Hospitalar Universitário de Lisboa Central, Lisboa
2 - Serviço de Farmácia, Centro Hospitalar Universitário de Lisboa Central
- EAACI Congress 2021, reunião internacional, apresentação sob a forma de E-poster
Resumo:
Introduction: Anticonvulsants (AC) are a common cause of cutaneous adverse reactions, especially in children. Systematic studies in this population are rare, and in vivo tests are seldom performed, making most of the hypersensitivity diagnosis probable but not confirmed. We report two cases of cutaneous adverse reactions, an exanthem and probably a DRESS syndrome, caused by AC, with positive patch tests to the suspected drugs.
Case 1: A 5-year-old girl with focal convulsive seizures developed on day (D) 11 of levetiracetam, D8 of phenytoin, D5 of valproic acid, and D3 of perampanel, a generalized, non-pruritic, maculopapular exanthem. There was no fever, adenopathy, face edema, mucosal involvement, vesicles, pustules, target lesions, eosinophilia, or altered liver function. All AC medication were stopped and replaced by clonazepam and topiramate, maintaining seizure's clinical control. Antihistamines and systemic corticosteroids were added, with progressive skin improvement over the next two weeks. Three months after the episode, patch tests were performed using all the suspected AC and were positive for valproic acid (10% in petrolatum) at 96 hour’s reading.
Case 2: A 10-year-old girl developed focal convulsive seizures in the context of a relapsing ependymoma and started levetiracetam, phenobarbital, phenytoin, and perampanel. On D9 of AC therapy, a maculopapular exanthem (trunk and arms) developed associated with fever. Two days later, the exanthem spread to the legs, the fever persisted, and liver enzymes raised. She was observed in the Allergy Department on D9, all ACs were stopped while antihistamines and systemic corticosteroids were introduced with prompt resolution of fever and progressive improvement of skin rash and liver dysfunction. There was transitory eosinophilia on the 12th day. There was no facial edema, adenopathy, or other organ involvement. Patch tests were performed three months afterward and were negative until the 7th day reading. They became positives to phenobarbital (20% in petrolatum) on the 11th day.
Conclusion: Immediate withdrawal of the suspected drugs after the prompt recognition of the first clinical signs is mandatory. Drug patch tests were safe and identified a probable T cellmediated hypersensitivity. Late patch test reading beyond the seventh day might raise diagnostic accuracy when an AC hypersensitivity was suspected.
Palavras Chave: Drug allergy; Anticonvulsant hypersensitivity.