Introduction: Renbök phenomenon describes the inhibition of a lesion when a different one appears. We describe the first case of Renbök phenomenon occurring in a context of erythema migrans (EM) spared by an amoxicillin-induced skin rash and we also present a literature review. Case report: A 60-year-old patient was treated with amoxicillin for EM on the right knee and subsequently developed generalized erythema as a result of an antibiotic-induced skin rash, with sparing of the area previously affected by EM. Renbök phenomenon was diagnosed. Discussion: In 1981, Cochran et al. first described a maculopapular drug reaction, which spared the sites of previous X irradiation for a tumor. Since then, nearly 40 cases have been reported, mostly describing patient with alopecia areata of the scalp with hair growth within plaques of psoriasis. One of the mechanisms suggested is a role played by cytokine cross-regulation in competition among distinct immune responses. Conclusion: We report the first case of Renbök phenomenon involving EM spared by a drug reaction. This phenomenon provides an insight into inflammatory response competition within a single patient. © 2017 Elsevier Masson SAS

Erythema migrans Lyme Drug eruption Borreliosis Renbök

skin disease human middle aged pathology doxycycline Humans case report female clinical article Article drug substitution adult Drug Eruptions antibiotic therapy drug tolerability amoxicillin drug safety skin manifestation erythema drug eruption Renbok phenomenon knee inflammation erythema chronicum migrans histopathology antiinfective agent Anti-Bacterial Agents