Stevens-Johnson Syndrome/Toxic Epidermal Necrolysis Overlap Syndrome: A Case Report

Abstract

Background: Stevens-Johnson syndrome (SJS) and toxic epidermal necrolysis (TEN) are uncommon, life-threatening acute mucocutaneous drug reactions characterised by keratinocyte apoptosis and epidermal separation occurring at the drug-host cell interface. SJS involves less than 10% of the total body surface area (TBSA), whereas TEN involves more than 30%. The intermediate spectrum, termed SJS/TEN overlap syndrome, involves 10-30% TBSA. Rapid identification, supportive care and early treatment are critically important because sepsis, multiorgan failure and mortality can develop rapidly. Case Presentation: A 44-year-old man presented with high-grade fever, significant systemic symptoms and a rapidly advancing erythematous maculopapular rash that quickly progressed to widespread blistering and sloughing. Significant mucosal involvement was also present, including severe ocular inflammation (bilateral conjunctival injection with eyelid crusting), painful oral ulcerations and genital lesions. Total epidermal detachment was estimated at approximately 15-20% of TBSA, with a positive Nikolsky sign, leading to a final clinical diagnosis of SJS/TEN overlap. The condition was attributed to the recent simultaneous administration, during the preceding two days, of newly introduced medications: betahistine, vitamin B12, etizolam, nandrolone decanoate, pregabalin/vitamin B12 combination capsules and cerebroprotein hydrolysate. Although the exposure to several new drugs meant that a specific causative agent could not be definitively identified, pregabalin and etizolam were strongly suspected as triggering agents because of their chronological association with the development of the rash. Laboratory results indicated elevated systemic inflammatory parameters, mild transient derangement of renal function and profound hypoalbuminaemia, while the total white cell count was normal (7,600/mm). Using the SCORTEN scoring system, the score was 2, which predicted a baseline mortality risk of 12%. Conclusion: Management consisted of immediate discontinuation of all newly introduced culprit medications and aggressive collaborative care, including intensive fluid therapy, close metabolic surveillance, intensive wound care, aggressive topical ophthalmic management and closely supervised systemic therapy with high-dose steroids (prednisolone 40 mg). The patient achieved complete and sustained epithelialisation, with no subsequent ocular or systemic sequelae. This case reinforces the value of rapid diagnosis, unequivocal withdrawal of precipitating agents and comprehensive multidisciplinary management in achieving favourable outcomes and reducing mortality in severe cutaneous adverse reactions.