Toxic epidermal necrolysis due to overdose of lamotrigine

A 7-year-old boy with epilepsy received sodium valproate(0.25 g in the morning and 0.5 g at night) for 2 years. Lamotrigine was added because of exacerbation of the illness. The dosage of lamotrigine on the first, second and third weeks were 12.5, 25.0, and 37.5 mg once daily, respectively. On day 15 of taking lamotrigine, he developed erythema on foot, accompanied by pruritus and reddening of the eyes. After that the boy developed erythema on entire body, blister on neck, arms and legs, erosion of oral mucosa occurred accompanied by fever. The boy was hospitalized on day 20 of taking lamotrigine. Laboratory tests showed the following values: white blood cell count 7.6×109/L, red blood cell count 3.9×1012/ L, hemoglobin 106 g/L, high-sensitivity C-reactive protein(hs-CRP) 5.5 mg/L, albumin 25 g/L, alanine aminotras nferase(ALT) 66 U/L, and aspartate aminotransferase(AST) 58 U/L. Lamotrigine was withdrawn, and the boy received the symptomatic treatments including anti-inflammation, anti-anaphylaxis, liver protection and fluid infusion. On day 3 of admission, the boy developed high fever, drowsiness and shiver. Laboratory tests showed the following values: ALT 47 U/L, AST 33 U/L, lactate dehydrogenase (LDH) 207 U/ L, creatine kinase 322 U/L, creatine kinase isoenzyme(CK-MB) 185 U/L, and alphahydroxybutyric dehydrogenase 258 U/L. Meanwhile vesicles appeared on erythematous skin and ulcers occurred. A large area of exfoliation appeared on his neck and face. Ulcers were red with exudates. The purulent secretion was secreted from dental ulcer surface. He was diagnosed as toxic epidermal necrolysis. Then the boy received complex treatments included methylprednisolone, compound glycyrrhizin, gamma globulin, and antimicrobial drug. On day 9 of admission, most liquid in the blister on the trunk and limbs were absorbed. Laboratory test showed the following values: LDH 205 U/L, creatine kinase 247 U/L, CKMB 31 U/L, ALT 28 U/ L,and AST 23 U/L.On day 13 of admission, the boy's vital sign were stable, erythema on the body disappeared. On day 15, he was discharged. The result of follow-up one year later showed no scars on the boy's skin. Key words: Lamotrigine; Epidermal necrolysis, toxic