P2.Q334: Identifying Id Reaction: A Case of an Autoeczematization after Bullous Tinea

Introduction: Autoeczematous reaction, or Id-reaction, is an immunological response to various infections including Tinea, Mallocum contagium, tuberculosis and BCG therapy. It is hypothesized similar to delayed type hypersensitivity with increased T-cell stimulation lowering irritant threshold and disseminated cytokines, which usually presents near the infection site and extends to non-affected areas. This case highlights the clinical presentation of Id-reaction secondary to Tinea infection.

Case Description: A 14-year-old female cross-country runner with a history of anemia presented with a worsening rash on her palms and feet persisting for 2 weeks. Six months prior, she had fungal infection treated with topical antifungal agents for 2 months, with resolution. Notably, the patient habitually soaked her feet in cold water with other athletes. Eleven days before presentation, tender ulcers developed on bilateral first toes that progressed into blisters with yellow foul-smelling discharge and purities. Given inability to ambulate, Patient’s mom gave leftover azithromycin 500mg daily for 3 days. Later, the patient developed migrating pruritic, non-erythematous rashes on her arms and chest.
Physical exam is significant for red, non-umbilicated papular rashes with multiple stages of healing and different diameters were noted on palms of hands and soles of the feet, extending to bilateral arms. On the first toes, tender ulcers crusted over with circumferential yellow discoloration of the skin without discharge were seen. HIV, RPR and Hep B and Hep C were negative. During admission, CMP, procalcitonin, ESR, and respiratory viral were unremarkable. Bilateral wound culture positive for multiple flora. Blister studies of HSV 1and 2 and VZV were negative. Dermatology was consulted and ID reaction was identified. Keflex 500mg TID x 5 days for staph coverage, and Ketoconazole 2% cream BID for Tinea. Triamcinolone 0.1% ointment BID was prescribed for Id-reaction. Full resolution was achieved 2 weeks post discharge.

Discussion: Id-reaction is a challenging diagnosis given its acute presentation with widespread extremely pruritic lesions away from the infection site making it hard to distinguish from medication allergy. Lesions typically last for 2-3 weeks, however prolonged symptoms have been reported up to 1-2 months focusing management on symptomatic relief.
Emerging data with case reports from 2 years old to 50 year old patients with Id-reaction to molluscum contagiousm infection, cutaneous larvae and lice have been reported.

Conclusion: It is important to be vigilant in detecting and treating ID reaction secondary to viral and fungal infection and to not mistaken such reaction for drug allergy.