Risk factors and mortality among patients with severe muco-cutaneous drug reactions.

INTRODUCTION: The aim of this study was to examine risk factors and mortality among patients with erythema multiforme (EM), Stevens-Johnson syndrome (SJS) and toxic epidermal necrolysis (TEN). METHODS: This was a retrospective evaluation of the med-ical records of 250 patients from two Danish tertiary dermatological departments during a ten-year period. RESULTS: In a total of 192 cases (77.4%), the primary diagnosis of EM (66.5%), SJS (62.2%) and TEN (100%) was confirmed, whereas the remaining cases (22.6%) were diagnosed differently. Antibiotics and allopurinol were predominantly associated with TEN, whereas SJS was associated with a broad spectrum of drugs. EM was related mainly to viral infections, predominantly herpes (30.6%); 38.2% of the causes of EM remained unknown. Patients with TEN had the highest mortality; i.e. 60% in the course of the ten-year study period: adjusted hazard ratio (HR) = 11.2 (95% confidence interval (CI): 3.65-34.35); p < 0.001 compared with EM patients. The risk of death was also increased among patients with SJS relative to patients with EM: HR = 2.60 (95% CI: 1.10-6.16); p = 0.030; however, this did not remain statistically significant after adjustment for age, co-morbidity, infection, cancer and polypharmacy, HR = 0.99 (95% CI: 0.38-2.57); p = 0.976. CONCLUSION: We validated diagnoses in 250 patients with EM, SJS and TEN diagnosed during a ten-year period. The survival of patients with TEN was expectedly low compared with patients with EM. We extend previous findings by showing that after adjustment for confounders, the survival rates of SJS and EM are comparable. FUNDING: none. TRIAL REGISTRATION: not relevant.