Dermatologic Emergencies: SJS/TEN Mimics

Dr. Lindy Fox presented information about dermatologic emergencies that mimic Stevens-Johnson syndrome/toxic epidermal necrolysis (SJS/TEN).

First, Dr. Fox described SJS/TEN, a severe skin reaction that causes damage to the skin and mucus membranes and can be life-threatening. Dr. Fox believes that SJS and TEN are two distinct conditions. SJS typically presents as targetoid lesions that start on photo-distributed skin areas with mucosal involvement. It may appear more inflammatory on histology. TEN presents as erythematous (red) skin that falls off.

Second, Dr. Fox discussed SJS/TEN mimics and how to distinguish them from SJS/TEN. TEN-like diseases that should be considered in the differential diagnosis include toxic erythema of chemotherapy (TEC) and graft versus host disease (GVHD). TEN mimics that are less severe but look dramatic include linear IgA bullous dermatosis, acute generalized exanthematous pustulosis (AGEP), and cutaneous reactions to targeted agents such as enfortumab, an anti-nectin-4 monoclonal antibody conjugated to monomethyl auristatin E used for urothelial carcinomas. SJS-like diseases that should be considered in the differential diagnosis include TEC, GVHD, AGEP, systemic lupus erythematosus, paraneoplastic pemphigus, and reactive infectious mucocutaneous eruption (RIME). Dr. Fox shared cases that demonstrate the differences in clinical presentation and histopathology between these diagnoses.

Third, Dr. Fox described TEC mechanisms of action, clinical presentation, diagnosis, and treatment. TEC is thought to be caused by extrusion of the chemotherapeutic agent into the eccrine glands. It is characterized by erythematous patches or edematous (swollen) plaques of the hands, feet, and intertriginous zones (skin folds) that present two days to three weeks after chemotherapy initiation. The initial distribution of these patches is critical to differentiating TEC, TEN, and GVHD. TEC symptoms include pain, burning, numbness, and itching. It has a characteristic dusky hue that is part of TEC pathophysiology. TEC may be more severe in the presence of sepsis, viral infections, combination chemotherapy treatment, hemophagocytic lymphohistiocytosis (HLH), and capillary leak syndrome.

The term TEC was created to provide an umbrella category for disparate reactions to chemotherapy. TEC may look different from patient to patient, but the original sites of involvement and morphology are consistent.

Treatment options for TEC include local and systemic therapies. Systemic therapy options include intravenous immunoglobulin (IVIG). High dose vitamin D appears to be a promising non-toxic option. Celecoxib is reasonable prophylaxis to prevent TEC. The literature suggests that pyridoxine is ineffective.

Register today for the 2025 Clinical Symposium.