On January 29th, our very own PGY-2 Hong Le, presented a case of the most well-known dermatologic emergency for our review: an elderly gentleman recently started on antibiotics for a urinary tract infection presents with a full body painful rash.
SJS and TEN are a spectrum of disease, TEN being more severe and SJS less severe. TEN covers >30% of total body surface area and SJS covers <10%. If between 10 and 30 percent of TBSA is covered by the rash, it is termed SJS/TEN overlap syndrome. A good way to estimate body surface area is to use the area of your hand as an estimate of 1%.
sure SJS/TEN is provoked by exposure to an inciting drug. Complete lists of drugs with reported association with this condition can be found online, but the most notable categories include allopurinol, antiepileptics, antibacterial sulfas, nevirapine (NNRTI), and NSAIDs ending in “-oxicam.” Patients with HIV have a particularly increased risk of developing SJS/TEN. The typical exposure period before reaction is 4 days to 4 weeks, but risk continued for 8 weeks after treatment with a new drug.
The classic description and progression of SJS/TEN on physical exam are as follows. First, a flu-like prodrome may occur (malaise, myalgias, arthralgias, and fever) 1-3 days before the onset of rash. When the rash begins, it is extremely painful, ill-defined, coalescing macules with purpuric centers on the face and thorax that spread diffusely and symmetrically. These lesions are typically termed “dusky.” It usually spares the scalp, palms, and soles. Soon vesicles and bullae form and within days, the skin sloughs. Mucosal surfaces are involved in >90% of patients, which may cause symptoms such as photophobia, conjunctival itching/burning, odynophagia, dysuria, and painful defecation. Nikolsky sign is positive in these patients (the skin sloughs when tangential pressure is applied). Other diseases with a positive Nikolsky sign include pemphigus vulgaris and staphylococcal scalded skin syndrome. The “wet newspaper sign” is also classic for SJS/TEN, the shiny and lighter tone of exposed skin after a layer of affected epidermis sloughs off. The SCORTEN score can be used to determine prognosis and severity of the condition.
Treating SJS/TEN is mainly supportive, including removing the offending agent, IV fluids, wound care, nutrition, and electrolyte repletion, but a multidisciplinary approach is necessary. Consults to dermatology, burn surgery, ophthalmology, OBGYN for a vaginal exam if the patient is female, and possible urology consult for males should occur immediately. High suspicion for infection and low threshold to start antibiotics are also beneficial.
There are multiple adjunctive treatments your dermatology consultants may recommend, but additional research is needed on most of them. Cyclosporine, anti-TNF drugs, steroids, IVIG, and plasmapheresis are a few of them.