ACUTE URTICARIA: IS THERE MORE UNDER THE ITCH?

Introduction Acute urticaria is a common disease and often the etiology is never identified. Allergic, infectious, rheumatologic, and malignant etiologies are known but testing is generally not conducted. Case Description A 30 y/o healthy man presented with acute urticaria and angioedema to the emergency room. He was administered epinephrine, steroids, antihistamines and admitted because his urticaria persisted. Allergy was consulted and he denied allergic triggers, medications, physical triggers but he was an avid outdoorsman who grew and ate his own vegetables. In addition to the hives, he endorsed low-grade fevers, arthralgias, myalgias, and abdominal pain. Exam demonstrated diffuse hives but no joint effusions or abdominal tenderness. Laboratory studies included negative HIV and hepatitis serologies, CRP 10.7, ESR 23, 30 eosinophils (3 days on steroids), IgE 77, and peripheral smear with microcytosis, erythrocytosis and neutrophilia. With non-specific studies, he was diagnosed with acute urticaria and treated conservatively. He continued to experience hives, at which point toxocara antibody was assessed and found to be positive. He was offered albendazole therapy but declined as his disease spontaneously resolved with no evidence of end-organ damage. Discussion Visceral larva migrans is caused by parasitic nematodes, most commonly toxocara canis. The nematodes travel through the intestinal wall and are distributed via the blood stream where they can cause inflammation and damage. The disease is usually self-limiting but can cause end-organ damage. Hives are frequently seen. Visceral larva migrans should remain on the differential for patients with appropriate exposure risks, hives, and other systemic symptoms.