This population-based observational study was designed to estimate the incidence and distribution of SJS-spectrum (Stevens–Johnson syndrome, toxic epidermal necrolysis, and toxic epidermal Necrolysis/Stevens–Johnson syndrome overlap) and chemical burns (alkali or acid burn of the cornea/conjunctiva) in the United States and extrapolate these numbers to the world.
All patients evaluated in 961 hospital-based US emergency departments between July 1, 2010, and June 30, 2012 were identified retrospectively using the Nationwide Emergency Department Sample (NEDS) from the Agency for Healthcare Research and Quality. SJS-spectrum and chemical burn cases were identified using the International Classification of Diseases, Ninth Revision, Clinical Modification diagnostic codes.
A mean of 3834 new SJS-spectrum cases per year were identified in the United States, resulting in an incidence rate of 12.35 new cases per million per year. Similarly, a mean of 15,865 new chemical burn cases per year were identified, resulting in an incidence rate of 51.10 new cases per million per year.
If the incidence of SJS-spectrum is approximately uniform the world-over, extrapolation from the US figure would amount to approximately 86,500 new cases per year in the world. Extrapolation of ocular chemical burns to the world is difficult because the incidence and severity are anticipated to be higher in the developing world than in the United States. Still, using a US incidence rate, a minimum of 357,710 burn accidents would be expected to occur worldwide every year; there are presently too few data available to calculate the degree of severity and bilaterality.
*Massachusetts Eye and Ear Infirmary, Harvard Medical School, Department of Ophthalmology, Boston, MA; and
†Clinical Research Center, Boston Children's Hospital, Boston, MA.
Reprints: Michelle L. White, MD, MPH, Massachusetts Eye and Ear Infirmary, 243 Charles St, Boston, MA 02114 (e-mail: Michelle_white@meei.harvard.edu).
J. Jang has no funding or conflicts of interest to disclose. The remaining authors are full-time employees of the Massachusetts Eye and Ear Infirmary (a not for profit organization) which is the manufacturer of the Boston Keratoprosthesis.
Received June 15, 2015
Received in revised form August 22, 2015
Accepted August 24, 2015