Case Presentation: A 45-year-old man with alcohol use disorder, immunocompetent HIV, chronic deep vein thrombosis on direct oral anticoagulant, and untreated plaque psoriasis presented with right 2nd digit pain and fever. The patient appeared ill with heart rate of 115 and respiratory rate of 25. On exam, the right 2nd digit was warm and diffusely edematous limiting mobility. Psoriatic plaques covered over 50% body surface area with underlying erythema, warmth, scaling, and sloughing. Laboratory tests showed leukocytosis, elevated inflammatory markers, and lactic acidosis. He was admitted for sepsis with concern for cellulitis and presumed septic joint complicated by alcohol withdrawal. He was initially treated with broad spectrum antibiotics, fluid boluses, and benzodiazepine protocol. Orthopedic consult ruled out septic arthritis, flexor tenosynovitis, and osteomyelitis and diagnosed psoriatic dactylitis of his right digit. Despite treatment, intermittent fevers, tachycardia, hypotension, and leukocytosis persisted. Multiple blood and wound cultures remained negative and several lactates remained normal. Multispecialty involvement with Rheumatology, Infectious Disease, and Dermatology determined the patient’s intermittent and recurrent signs of sepsis were attributed to severe erythrodermic psoriasis (EP). Methotrexate and cyclosporine were contraindicated given the patient’s underlying alcoholic liver disease, so he was treated with triamcinolone ointment, calcipotriene ointment and cool saline soaks. He slowly recovered and outpatient follow-up was arranged for initiation of tumor necrosis factor inhibitor therapy.
Discussion: Erythrodermic psoriasis (EP) presents a diagnostic and therapeutic challenge given its similarities to acute sepsis and therefore may be easily overlooked as the direct cause for a patient meeting the criteria for systemic inflammatory response syndrome. Making it more difficult, patients with EP are at an increased risk for superinfection, especially due to Staphylococcus aureus. Therefore, patients will often require serial blood cultures in order to confidently discontinue antibiotics. Risk factors for EP include personal or family history of psoriasis, alcohol use, infection, and HIV. The pathophysiology of erythroderma includes vasodilation and shunting of blood to the skin leading to diffuse erythema, increased cardiac output, fluid loss, impaired thermoregulation, and even shock which clinically mimics infection. Treatment recommendations remain somewhat unclear due to a lack of high-quality studies. Consequently, the National Psoriasis Foundation Medical Board developed a consensus on treatment guidelines via literature review, however; their conclusions remain ambiguous and depend on acuity and severity of illness as well as comorbidities. Overall, the suggested first line therapies for severe cases of erythrodermic psoriasis are cyclosporine or infliximab.
Conclusions: This case is important for hospitalists to be aware of because it demonstrates the difficulties in diagnosing and treating erythrodermic psoriasis since its clinical presentation is nearly identical to sepsis. Hospitalists must remain vigilant in monitoring for the many complications associated with EP and acknowledge that patients will often present with signs and symptoms of persistent sepsis without true infection.