A Case of Contact Toxic Epidermal Necrolysis

A 24-year-old woman presented with a 12-day history of erythema, papules, and itching on both hands and a 1-day history of a generalized rash with blisters. Notably, the patient was an investigator at a pharmaceutical company, and her work involved the manipulation of halogen bromoacetonitrile (BAN). The physical examination is shown in Figure 1. The patient was admitted to our hospital with contact dermatitis and received relevant symptomatic and supportive treatments, including initial intravenous prednisone (75 mg/day). The patient's condition continued to progress dramatically Figure 2. New lesions, including dark erythema and blisters that tended to fuse, the Nikolsky sign, and gradual massive erosions emerged to expose a large area of the dermis, accompanied by humid bleeding. The eyes, mouth, and genitals were also involved. The maximum dose of glucocorticoids was increased to 199 mg of prednisone daily, which was gradually reduced after disease control. Immunoglobulin (20 g/day) was administered for 7 days. Hemofiltration therapy was performed three times in the intensive care unit. Simultaneously, correction of hypoproteinaemia, regulation of electrolyte imbalance, fluid infusion, gastric mucosa protection, anti-infection, and hepatoprotective treatments were prescribed, with skin and mucous membrane care playing a crucial role in the patient's recovery. The skin lesions gradually improved Figure 3. Her discharge diagnosis was revised to contact toxic epidermal necrolysis (CTEN). Allergic contact dermatitis is a type IV hypersensitivity reaction with mild progress that occurs in previously sensitized individuals. In the present case, the patient progressed dramatically to CTEN, which is rare. In this condition, Fas ligands and related cytokines, mediated by cytotoxic CD8+ T cells, appear in the lesional epidermis and blisters. Fas/Fas ligand is coexpressed in many keratinocytes of lesional skin, resulting in massive epidermal destruction. This condition is dangerous and associated with a high mortality rate. CTEN caused by ultraviolet curing ink and S, S-dimethyl cyanoimidodithiocarbonate has been reported.1-2 In the present case, the suspected sensitizer was BAN. BAN, a type of halogenated acetonitrile with the chemical formula C2H2BrN and a molecular weight of 119.948, is used for the chemical synthesis of new pharmaceutical products. Halogenated acetonitriles are emerging as a disinfection by-product that can be detected in various aquatic environments and are cytotoxic, genotoxic, mutagenic, and tumorigenic both in vitro and in vivo. BAN exposure induced liver and kidney injury and disrupted metabolic pathways of amino acids, energy, and lipids in mice.3 At present, the treatment of TEN primarily includes timely withdrawal of the suspected sensitizer, glucocorticoids combined with immunoglobulins, and active skin care. A few nonpharmacological options for toxic epidermal necrolysis, including plasmapheresis and hemofiltration, have also been proposed. Continuous hemofiltration can efficiently control fluid balance and azotaemia and may be beneficial by rapidly removing noxious molecules and cytokines.4 Continuous hemofiltration may be a safe and effective adjuvant therapy for patients with refractory or severe toxic epidermal necrolysis.5 In the current case, three hemofiltration treatments were administered, which played a crucial role in disease control. Thus, hemofiltration may be an option for patients with an unsatisfactory response to conventional treatments.Figure 1: Patient's lesion on admission (a and b) Scattered bright red to dark red oedematous erythema and papules on both hands (c and d) the lateral aspect of the right thigh and the trunk with partial coalescence into large lesions. The erythema comprised scattered 1 to 10 mm blisters. No scales, erosions, or pustules were observedFigure 2: The patient's condition continued to progress dramatically with prednisone 75 mg/dayFigure 3: The skin lesions gradually improved after treatmentDeclaration of patient consent The authors certify that they have obtained all appropriate patient consent forms. In the form, the patient(s) has/have given his/her/their consent for his/her/their images and other clinical information to be reported in the journal. The patients understand that their names and initials will not be published and due efforts will be made to conceal their identity, but anonymity cannot be guaranteed. Financial support and sponsorship Nil. Conflicts of interest There are no conflicts of interest.