Other findings reported in this research letter include the following:
• 187/708 patients (26%) were admitted to critical care or burn units and 127 (17.9%) died in the hospital or within 60 days of hospital discharge (short-term mortality rate of 23.4% for patients with toxic epidermal necrolysis [TEN] and 9.0% for Stevens-Johnson syndrome [SJS])
• Forty-two of the remaining patients (n=581; median follow-up of 1283 days) were hospitalised for a subsequent episode; 8 (1.4%) experienced multiple recurrences. The median time to first recurrence was 315 days (IQR, 216-411 days). Critical care admission rates (26%; 95% CI, 23.2%-29.7%) were similar at the index admission and subsequent episodes.
• In light of the reported incidence of SJS and TEN in the general population (1.0-7.2 cases/1 million individuals/year), the observed recurrence risk in this study (>7%) is several thousand-fold higher than would be expected if subsequent episodes were probabilistically independent of the first episode.
The authors did not have direct access to patient records, and so were not able to look at medication exposures. Regardless, they say that their results are relevant to healthcare professionals who care for patients who have a history of these life-threatening conditions. As they primarily develop as idiosyncratic responses to drugs, the high risk of recurrence should be recognised, and the benefits of drug therapy weighed carefully against the potential risks.