Possible Diclofenac-Related Fulminant Toxic Epidermal Necrolysis: A Case Report

Toxic epidermal necrolysis (TEN) is a rare but life-threatening cutaneous adverse effect characterized by extensive epidermal detachment and systemic inflammation. Though anticonvulsants, sulfonamides, and allopurinol are most frequently associated with TEN, nonsteroidal anti-inflammatory drugs (NSAIDs) such as diclofenac have been involved in very few case reports. This case study presents a 76-year-old man with tophaceous gout who, after a self-administered single dose of 75 mg intramuscular diclofenac, developed fulminant TEN. At the time of hospital admission, the patient's skin showed progressively developing purpuric and bullous lesions covering 40.5% of the total body surface area, a positive Nikolsky sign, severe mucosal involvement, metabolic acidosis, acute kidney failure, thrombocytopenia, and multiorgan failure. Despite aggressive supportive care management, the patient died shortly after hospital admission. Based on the SCORe of Toxic Epidermal Necrosis (SCORTEN) severity score of 5, the patient was classified as having a very high risk of mortality, corresponding to an estimated mortality rate of approximately 85%. Using the Naranjo algorithm for evaluating the causal relationship between a drug therapy and a possible side effect, we obtained a score of 2, which points to a possible side effect, while the re-exposure to febuxostat, etoricoxib, and pregabalin was an alternate pharmacological variable during the course of the adverse event. This case highlights the potential for rapidly progressive and fatal TEN following recent NSAID exposure and underscores the importance of early recognition, prompt withdrawal of suspected medications, and careful causality assessment in patients receiving multiple drugs.