TY - CHAP M1 - Book, Section TI - Serum Sickness–Like Reaction A1 - Shah, Ashish A1 - Sobolewski, Brad A1 - Mittiga, Matthew R. A2 - Knoop, Kevin J. A2 - Stack, Lawrence B. A2 - Storrow, Alan B. A2 - Thurman, R. Jason PY - 2021 T2 - The Atlas of Emergency Medicine, 5e AB - Serum sickness–like reaction is characterized by rash, fever, angioedema of the face, hands, and feet, and polyarthralgias/polyarthritis, with onset 1 to 2 weeks following exposure to an offending agent, and resolves within 1 to 2 weeks after exposure is discontinued. It is felt to occur via an immune complex–mediated mechanism and can be precipitated by exposure to a number of drugs, with trimethoprim-sulfamethoxazole, cephalosporins, and penicillins being most common. Almost all patients develop a polymorphous pruritic rash that starts in the trunk, groin, and axillae, eventually spreading to the limbs. The urticarial lesions are longer lasting than typical hives. Some patients can exhibit palpable purpura, maculopapular lesions, or target lesions reminiscent of erythema multiforme but without evidence of blister formation. In all patients, the mucous membranes are spared. Almost all patients develop remittent fever without temporal spikes. Other symptoms include arthralgias, angioedema, and rarely, frank arthritis. The differential diagnosis includes viral exanthems, hypersensitivity vasculitis, scarlet fever, acute rheumatic fever, meningococcemia, disseminated gonococcemia, reactive arthritis, Lyme disease, Still disease, and Stevens-Johnson syndrome. SN - PB - McGraw-Hill CY - New York, NY Y2 - 2024/03/29 UR - accessemergencymedicine.mhmedical.com/content.aspx?aid=1181044480 ER -