RHABDOMYOLYSIS INDUCED URTICARIA: A COMPELLING REASON TO PROCRASTINATE - A CASE REPORT

Abstract

<h3>Introduction</h3> Urticaria is an allergic reaction comprising of itchy, red, raised bumps that appear on the skin that come and go. Most feared complications of urticaria is angioedema and anaphylactic shock. <h3>Case</h3> A 46 year old caucasian male with a past medical history of shellfish allergy and asthma who presented to the hospital with complaints of erythematous, raised, pruritic rash on his body after strenuous weight lifting workout. He does moderate intensity exercise regularly. Patient had a similar episode about 8 years ago with exercise that required hospitalization but otherwise denied any new occupational exposures, illnesses, bug bites or medication use. He was started on intravenous corticosteroids, benadryl, pepcid and fluids. Significantly elevated CPK of 8,788. Diagnosis was postulated as exercise induced urticaria. Allergist suggested the diagnosis was likely rhabdomyolysis induced urticaria, as patient has been developing these episodes only during intense work outs resulting in rhabdomyolysis but otherwise, he is able to exercise regularly without the rash. With aggressive fluid resuscitation, the patient's CPK trended down and his rash improved. <h3>Discussion</h3> Rhabdomyolysis induced urticaria is a rare, distinct entity. The key differentiating factor between exercise induced urticaria and rhabdomyolysis induced urticaria is that the former occurs with regular exercise from sweating, but the latter occurs only during episodes of strenuous workouts resulting in rhabdomyolysis. The treatment modality consists of fluids to bring down the CPK levels, corticosteroids, H1 and H2 receptor antagonists to treat the rash. It can present as a diagnostic challenge in determining the cause of urticaria if CPK is not tested.