SCORCH: Recognizing Trimethoprim-Sulfamethoxazole Hypersensitivity and Common Inpatient Dermatology Mimickers

Conclusions

• SCORCH appears to be a distinct, rapidly onset trimethoprim-sulfamethoxazole hypersensitivity syndrome marked by sunburn-like erythema, conjunctivitis, lymphopenia, and hemodynamic instability.
• The syndrome often follows re-exposure, improves quickly after stopping TMP-SMX, and usually resolves with supportive care rather than prolonged immunosuppression.
• Key clues that favor SCORCH over DRESS, SJS/TEN, AGEP, or simple drug eruption are the very short latency, lack of eosinophilia or pustules, absence of mucosal erosions or epidermal detachment, and rapid recovery.
• Because severe shock-like reactions can occur with re-challenge, patients who develop SCORCH should avoid TMP-SMX permanently and have it documented as a high-risk allergy.
• Recognition of the characteristic clinical pattern may prevent unnecessary biopsies, prolonged hospital workups, and repeated steroid treatment when the patient is actually improving as expected.
• Rumpel-Leede phenomenon is a benign, pressure-induced purpuric eruption that can mimic vasculitis but is localized distal to a compression site such as a blood pressure cuff.
• Acute inflammatory edema is a common pseudocellulitis in critically ill, fluid-overloaded patients that presents with dependent erythematous edematous plaques while sparing pressure areas.
• Identifying acute inflammatory edema can spare patients unnecessary antibiotics, cultures, biopsies, and extensive cellulitis evaluations.
• Overall, the presentation argues that careful pattern recognition in inpatient dermatology can meaningfully change management by distinguishing dangerous drug reactions from benign mimics.