Development of cold urticaria after cryotherapy during laser epilation for pilonidal disease: a case report.

INTRODUCTION: Laser epilation is utilized to reduce pilonidal disease (PD) recurrence and commonly employs cryotherapy for analgesia. Cryotherapy can lead to cold urticaria, particularly in patients with unrecognized cold sensitivity. We report two cases of cold urticaria that developed during laser epilation for PD patients. CASE PRESENTATION: Case 1: A 14-year-old female with a pilonidal abscess underwent a drainage procedure followed by the Gips procedure and laser epilation. During the initial laser session, she developed urticarial wheals in the area exposed to cryotherapy. The urticaria resolved with oral diphenhydramine. At subsequent laser sessions, analgesia was provided using topical lidocaine. She exhibited no PD symptoms 3 years after treatment. Case 2: A 17-year-old male underwent a drainage procedure for a pilonidal abscess and subsequently underwent the Gips procedure. Laser epilation was initiated, during which he developed urticaria in the area exposed to cryotherapy. After the cessation of laser and cryotherapy, his symptoms resolved spontaneously. Analgesia for subsequent laser sessions was provided using topical lidocaine. He experienced no recurrence of PD at 6 months post-treatment. DISCUSSION: Cold urticaria is triggered by cold exposure and presents with wheals during rewarming. Cold-induced autoallergen and IgE-mediated mast cell degranulation lead to histamine release. Recognition is critical, especially in patients who lack prior cold exposure. Timely antihistamine administration and cold stimuli avoidance can effectively mitigate the symptoms. By comparison, laser-induced urticaria can present hours after laser application and may require corticosteroids for treatment. CONCLUSION: Cold urticaria can develop after cryotherapy during laser epilation. Awareness, prompt recognition, and the use of alternative analgesia can ensure the safe continuation of laser therapy for PD patients.