Demodicosis Mimicking Papulopustular Eruption in the Setting of Targeted Therapy

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Iulianna Taritsa
Shikha Walia
Jennifer Choi


Demodex, demodicosis, immunomodulatory drugs, cancer, oncology, adverse effects


Here we discuss the dramatic cutaneous reactions of two patients receiving targeted therapies for cancer (one on a MEK inhibitor/BRAF inhibitor and the other receiving carfilzomib). Demodicosis was the underlying cause in both cases, though the infection was mistaken for a reaction to the patients’ complex malignancy therapies. Given the prevalence of cutaneous side effects of chemotherapy and targeted cancer therapies and the protean nature of demodicosis, it follows that demodicosis may be easily mistaken as a drug reaction to a chemotherapeutic agent. Demodicosis in the setting of chemotherapy and immunosuppression must thus remain an important diagnostic consideration in patients undergoing cancer treatment to allow for appropriate diagnosis and management of cutaneous findings without discontinuation of essential chemotherapy.


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