PA22 Topical tacrolimus management of chronic recurrent skin reaction to mauve stinger jellyfish envenomation

Abstract Chronic skin eruptions may follow the acute reaction to envenomation by some jellyfish, incidence and management of which are not well described. We describe with topical tacrolimus a chronic eruption following Pelagia noctiluca (‘mauve stinger’), one most common stinging jellyfish in Mediterranean Sea. An 8-year-old girl was stung on arm P. Menorca, Spain. First-aid measures vinegar antihistamine were administered, discomfort settled within 24 h. Five days later, sting site became increasingly painful itchy, superficial ulceration swelling. A second lower leg reacted similar manner. She systemically well. treated oral co-amoxiclav, fusidic acid betamethasone valerate 0.1% cream, nonadhesive dressings. initially responded well, but required continue use potent steroid after 3 weeks, as symptoms recurred 48 h halted application. The cream 0.03% achieved symptom control when used slowly weaning regime over months, brief flare around time contracting COVID-19. has now been asymptomatic for 12 is maturing scar. Envenomation reactions phylum Cnidaria (including noctiluca) result varying pathophysiological mechanisms. tentacles bell carry toxin-releasing epithelial organelles called nematocysts. When triggered, apparatus fires, injecting thousands mineralized spine-covered tubules toxins such porins [Yanagihara AA, Wilcox C, Smith J, Surrett GW. Cubozoan envenomations: clinical features, pathophysiology management. In: Cnidaria, Past, Present Future (Goffredo S, Dubinsky Z, eds). Cham: Springer, 2016; 637–52]. Acute tissue damage inflammation caused physical trauma venom effects. Vinegar at permanently prevent discharge from unfired noninjected Hot-water immersion 30 min inactivates venom, steroids reduce inflammation. delayed prolonged response (presenting primary envenomation), our case, likely be an immunological retained, embedded nematocyst structures include granulomatous reactions, eventually scarring. Optimal first-aid (as above) thought late sequelae. This report highlights successful immunomodulation established reaction.