A CASE SERIES: CHRONIC INDUCIBLE URTICARIA FOLLOWING COVID-19 INFECTION AND MRNA VACCINE

INTRODUCTION: Chronic inducible urticaria (CIndU) is a subgroup of chronic urticaria triggered by an environmental stimulus. While skin manifestations following COVID-19 infection and vaccination have been discussed, there is sparse literature documenting CIndU associated with COVID-19. We present two cases of CIndU, one following COVID-19 infection and the other following a COVID-19 mRNA vaccine. CASE DESCRIPTION: The first patient is a forty-seven-year-old male who presented with pruritic urticaria after being diagnosed with COVID-19. Identified triggers included scratching his skin and hot showers. Physical urticaria testing revealed dermatographism with light scratch. The patient was treated with cetirizine 10 mg daily and symptoms improved. Based on his clinical history, the patient was diagnosed with CIndU. The second patient is a fifty-year-old female who presented with urticaria triggered by physical touch for 7 months. Symptoms began 2 weeks after her third dose of a COVID-19 mRNA vaccine and have persisted despite daily cetirizine at 10 mg. A fourth booster resulted in a 1 week increase in symptoms. DISCUSSION: We present two cases in which patients report new onset CIndU. The first patient reported CIndU at the onset of a COVID-19 infection and the second patient reported CIndU 2 weeks after a COVID-19 mRNA vaccine. A review of the literature revealed only limited reports of new onset CIndU after COVID-19 infection or vaccination. This case series adds to the current literature with continued demonstration of an association between COVID-19 and CIndU. Further investigation could aid in better understanding the pathophysiology and ideal treatment of CIndU.