Overt nickel and cobalt hypersensitivity after pipeline embolization device placement: A case report

Nickel and cobalt are frequently found in metallic alloys used in the manufacture of aneurysm clips and endovascular prostheses, such as the pipeline embolization device (PED). Nickel hypersensitivity can affect up to 15% of the population, however, it is very rarely overt in patients who undergo endovascular stent placement. Here, we present the case of a 35-year-old woman who developed allergic symptoms after PED placement and was later confirmed to be allergic to both nickel and cobalt by patch testing. Fortunately, she responded well to pharmacologic treatment, rendering surgical intervention unnecessary. To the best of our knowledge, this is the first report of symptomatic nickel hypersensitivity, and the second report of symptomatic cobalt allergy caused by the PED. Despite its low prevalence, we believe that surgeons should actively inquire patients in the postoperative period about allergic symptoms, to facilitate early diagnosis and treatment.