Photo-induced toxic epidermal necrolysis caused by clobazam

Abstract

Toxic epidermal necrolysis (TEN) is a life-threatening disease, the pathogenesis of which remains largely unknown. We describe a 23-year-old woman under treatment with clobazam who developed lesions of TEN In light-exposed areas. Patch and photopatch tests with clobazam were negative. The cellular phenotype and cytokines were studied in blister fluid. The cellular infiltrate was composed mainly of T lymphocytes with a predominant cyloloxic phenotype. Tbere was an increase in the level of tumour necrosis factor (TNI')-rv in blister fluid compared with the control (a patient with bullous pemphigoid).'iOxic epidermal necrolysis (TEN) or I.yell's syndrome is a rare but serious disease caused by necrosis of the epidermis, which gradually acqtiires a scalded appearance. The incidence of TEN is low. there being some 10 cases per million people eacb year and. although its origin is sometimes unknown, in most patients it is ihought to be a reaction triggered by drugs, mainly sulphonamides. anticonvulsants and non-steroidal anti-inllammatorics.' The pathogenesis of TEN is unknown, although it is well accepted that the mechanism hy which these lesions are produced is through a cell-mediated reaction. Occasionally, circulating immune complexes have been ibtind. We present a case of TEN in photo-exposed areas in a patient who was being treated with clobazam. Case reportA 2 5-year-i)ld woman had no relevant personal or iamiiy history except for a patch of alopecia areata on the scalp, for which she had been treated with 20mg/ day clohazani over the previous 14 days. She presented at ibc emergency unil with a pruriginous and erythematous eruption, located mainly in the facial region, on the thorax, back and limbs, which had appeared some 2 days previously. 3(ih after sun exposure on the beach. Examination revealed extensive erythematous areas with flaccid bullae and erosions, which were confltient in the aibrementioned areas, and which were absent in the areas covered by the swimsuit (Fig. 1). Nikolsky's Correspondence: Dr P.Redondo, Department of Dermatology. Hiiiversily Clinic ofNavarra, PO tiox 192. 3il)Sl}. Pamplona, Spain. sign was positive. She had involvement of the oral and genital mucosae. and had bilateral coniunelival injection. As there was clinical suspicion of Slevens-Jt)hnson syndrome or TEN. a skin biopsy was performed. This confirmed Ibe diagnosis of TEN. Clobazam therapy was stopped. Pentoxifylline (9()()mg/day)^ and a prophylactic systemic antimicrobial were administered, and supportive measures were started. The erythema progressed, with denudation over the face. neck, upper third of the torso and limbs, without affecting the non-exposed areas of the breasts, abdomen, pubis and buttocks.Within 36 b. Ihe progression had stopped, and the erythema gradually abated. Epithelialization of the denuded areas was largely completed 10 days after therapy with pentoxifylline was started. The patient was discharged from hospital 20 days after admission. The morphological appearance, the extent of involvement ( 3()-40'/{i...

Risk of toxic epidermal necrolysis and Stevens-Johnson syndrome associated with benzodiazepines: a population-based cohort study

“…SJS or TEN associated with other benzodiazepines have been scarcely reported in the literature, i.e., 2 TEN episodes under treatment with flurazepam [35] and clobazam [36], respectively, and 3 SJS episodes, i.e., 1 after chlordiazepoxide overdose [37] and 2 under treatment with clobazam [38] and nitrazepam [39], respectively, both in combination with anticonvulsant drugs. In spite of these communications of cases to pharmacovigilance registers and publications, and the high use of benzodiazepines in Western countries [40], a formal study estimating the risk of SJS/TEN associated with these drugs is lacking in the literature.…”

Toxic epidermal necrolysis

“…4 Two case of TEN have been reported in which the bullae and erosions occurred in sun-exposed areas. 53,54 These patients presented with typical features of fever, mucositis, and erosions, but the erosions were limited to light-exposed skin. Subsequent photopatch tests were negative.…”

Toxic epidermal necrolysis and Stevens-Johnson syndrome

“…Case reports exist for hydroxchloroquine [58], naproxene [59] and clobazam [60]. An often addressed issue is the induction of TEN or SJS after vaccination.…”