Abstract Introduction Porphyria-like bullous eruptions represent an uncommon ICU dermatologic finding and may arise from metabolic, infectious and immune-mediated processes. Classic porphyrias involve defective heme biosynthesis, whereas pseudoporphyrias share similar histological features without serum porphyrin elevation, often secondary to photoactive agents or renal failure. Streptococcal toxic shock syndrome (TSS) is a toxin-mediated illness characterized by multiorgan dysfunction and vascular injury; however, its association with porphyria-like eruptions has not been described. We present a critically ill patient with streptococcal TSS who developed expanding hemorrhagic bullae and necrotizing fasciitis with biopsy findings consistent with porphyria or pseudoporphyria. Case A 70-year-old man with chronic kidney disease presented with one week of ankle pain initially treated as gout with prednisone. Within days, blistering and skin darkening developed. On hospital arrival, he was hypotensive with lactic acidosis, acute kidney injury (AKI), transaminitis and group A Streptococcus bacteremia. Meeting criteria for streptococcal TSS, he was fluid resuscitated and given penicillin. The next day, hemorrhagic bullae expanded across both lower extremities and elbows. Mildly elevated international normalized ratio and thrombocytopenia were noted. Computed tomography (CT) and magnetic resonance imaging of the extremities revealed soft-tissue and subcutaneous gas concerning for necrotizing fasciitis. He received intravenous immunoglobulin for worsening dermatologic findings and multiorgan dysfunction. His AKI progressed to renal failure with pulmonary edema, requiring continuous veno-venous hemofiltration. A skin biopsy was performed for suspected purpura fulminans. Histopathology demonstrated subepidermal blistering, dermal papillae preservation, absence of inflammatory cells, and deposition of immune complexes along superficial dermal vessels, findings most consistent with porphyria or pseudoporphyria. Deeper sections revealed mild vasculitis. Urine and plasma porphyrin fractionation and protein C levels were normal. Following biopsy, ruptured bullae exposed underlying necrotizing fasciitis. Despite debridement and antibiotics, he developed ischemic limb changes, declined further surgery, and transitioned to comfort care. Discussion Streptococcal TSS is rare yet life-threatening, with this case highlighting an intriguing and rarely described dermatologic manifestation. Although pseudoporphyria is frequently associated with dialysis, our patient developed hemorrhagic bullae prior to renal replacement therapy. Recognizing a potential association between streptococcal TSS and pseudoporphyria broadens the clinical spectrum of the disease, placing it alongside other dermatologic entities such as purpura fulminans and disseminated intravascular coagulation. The porphyria-like histology involving immune complexes without inflammatory cells may provide further insight into the toxin-driven injury of TSS and its similarities to photoactive agent-induced dermal damage, as well as its potential for progression to deeper, life-threatening necrotizing fasciitis. This abstract is funded by: None
Melamed et al. (Fri,) studied this question.