Toxic epidermic necrolysis: a high-mortality pathology

Abstract

Toxic Epidermal Necrolysis (TEN) is a disease caused by delayed hypersensitivity reaction to drugs such as NSAIDs, allopurinol, carbamazepine and phenytoin. Its incidence: 0.5 - 1 cases per million persons, with a mortality of 30 - 60%. Erythematous macules-papules with blister of serous content and denudation ≥ 30% of body surface are observed on the skin. It affects the mucous membranes and is accompanied by fever, general discomfort, and myalgia, resulting in sepsis, acute renal failure, acute respiratory failure and Multiorgan Dysfunction (MOD). The prognosis is based on the SCORTEN Score, which assesses age ≥ 40 years, plasma urea ≥ 28 mg/dl, affected body surface area ≥10%, serum bicarbonate ≥ 20 mEq/L and plasma blood glucose 250 mg/dl. A SCORTEN of ≥ 5 points indicates a mortality > 90%. The pathogenesis is genetic, related to the HLA system, activation of CD8 + T lymphocytes, Natural Killer cells, FasL activation, perforin, granzyme B and granulosin, TNF α and If γ. The biopsy reveals epidermal necrosis with inflammatory infiltration and dermo-epidermal detachment. The treatment is based on the administration of Immunoglobulin.

Case presentation: 75 year old female patient with a history of chronic arterial hypertension and hypothyroidism. Religion: Jehovah's Witness. No allergic history. He was admitted to the ICU with a diagnosis of Hemorrhagic Stroke, requiring dexamethasone and phenytoin. At 3 weeks he manifested fever, general discomfort and the appearance of blisters erythematous lesions on the face, abdomen, back, both buttocks, thorax and armpits, and other ulcerated types in the mouth and labia majora. In addition, he developed acute respiratory failure, sepsis and MOD. Phenytoin was suspended. Skin biopsy showed epidermal necrosis with subdermal detachment, with perivascular mononuclear leukocyte infiltrate. The SCORTEN was 5 points. Due to the religious creed of the patient, treatment with Immunoglobulin was not initiated. Subsequently the patient obitiated.

The TEN is uncommon and high mortality, so the pharmacological choice must be careful. The diagnosis is based on skin biopsy processed with Hematoxylin/Eosin staining. Immunoglobulin treatment and critical support should be early.