3077 Hypersensitivity Syndrome Associated with Phenytoin Sodium

Tuesday, 6 December 2011
Poster Hall (Cancún Center)

Elizabeth Mendieta, Doctors in training , Author, Mexico City , Mexico

Background:

The Drug - Induced hypersensitivity syndrome (DIHS)  is a systemic reaction for drug-induced idiosyncratic. We report 1 in 1000 to 1 in 10,000 exposures to aromatic anticonvulsant. In the case of phenytoin is estimated at 2.3 to 4.5 per 10,000 exposures. There is a deficit of microsomal epoxide hydroxylase causing accumulation of toxic metabolites .  Occurs between 2 weeks to 3 months after drug  exposure. it is characterized by maculopapular rash, erythema midface, fever,  lymphadenopathy, with alteration of the hematologic system with eosinophilia,  peripheral or atypical lymphocytosis . Described reactivation of herpes virus (HHV-6 and 7) . Comorbidities during the syndrome  such as   type 1 diabetes, encephalitis,  and long-term sequelae such as thyroid dysfunction, systemic lupus erythematosus, etc.  ¹

Methods:

We report a 39 year old female with history  of traumatic brain injury (TBI) received proflaxis with phenytoin sodium 100 mg 1vo c / 8hrs, 4 weeks after starting with  fever, malaise, sore throat , cervical lymphadenopathy, appeared itchy rash in face, neck. Admitted with malaise, generalized rash, edema midface, cheilitis, jaundice, cervical lymphadenopathy, axillary and  inguinal and hepatomegaly.

We continue to study as probable hypersensitivity syndrome asking paraclinical studies including blood count, liver function tests.

We initiated 1mg/kg/day  prednisone for 6 weeks and subsequent dose reduction. Exit  after 5 days of hospitalization for clinical improvement. 

Continuous current monitoring by the outpatient department of our hospital and late complications that can occur in this syndrome

Results:

Liver function tests as well as the count of the white series was abnormal, with the following report : AST (177 U / L), ALT (154 U / L)WBC (12.430 mm³), eosinophil  (1.310 mm³).  

Biopsy report: Unavailable

Conclusions:  

Aromatic anticonvulsants (phenytoin, carbamazepine and phenobarbital) are frequent causes of DIHS . Treatment involves discontinuation of the drug involved, admission to intensive care and systemic steroids at doses of 0.5 to 1mg/kg/day and intravenous immunoglobulin 2g/kg. 

Bibliography:  

1. Kano Y, Shiohara T. The variable clinical picture of drug-induced hypersensitivity syndrome (DIHS)  in relation to the eliciting drug. Immunol Allergy Clin North Am 2009;29(3): 481–501.