(BMJ)—An otherwise healthy 8-year-old boy presented with pain, redness, and a burning sensation on the R side of his abdomen after swimming. Exam: vital signs WNL; no resp distress; serpiginous red rash on flank, with edema and purple streaks; labs WNL. What’s the dx?
Vibrio cellulitis
Cutaneous larva migrans
Cercarial dermatitis
Jellyfish sting
Fire coral dermatitis
You are correct. The boy had been stung by a large jellyfish. Jellyfish tentacles penetrate toxin-coated extensions via intracytoplasmic organelles (nematocysts) into the skin. Vinegar can inhibit nematocysts; washing with sea or salt water is also recommended. Some types of jellyfish stings cause catecholamine release (Irukandji syndrome); sx include cyanosis, arrhythmia, resp failure, dermal necrosis, anaphylaxis, HTN, and secondary renal failure.

First aid was performed locally with tetanus vaccine and antihistamines, and the patient’s wound site was washed with vinegar. In the ED, the sting was treated with IV hydration, acetaminophen, and cefazolin. Vinegar containing 4% to 6% acetic acid and alternating applications of ice were applied locally, and he recovered well.

Archives of Disease in Childhood 2021;106:811