Nephrogenic fibrosing dermopathy (NFD) and calciphylaxis are rare conditions that are associated with chronic kidney disease. Histopathologic changes, including dystrophic dermal calcification, often in association with elastic fibers have been observed in NFD and calciphylaxis. A pattern of dermal elastic fiber calcification that mimics pseudoxanthoma elasticum (PXE) has been previously reported as an incidental finding in the setting of calciphylaxis. Despite a shared association with renal disease and abnormal calcium deposits, however, NFD and calciphylaxis are discrete pathologic processes with distinct clinical and histopathologic features. Criteria for each are reviewed through case presentation of a patient meeting the clinical and histopathologic criteria for both NFD and calciphylaxis with histologic features mimicking PXE.

This study supports the existence of a subset of nevi on or near the ear that, like certain nevi located on other special sites, exhibit unusual but characteristic features, which may be misinterpreted as atypical or malignant.

The clinical and histopathologic features of this case are consistent with a diagnosis of linear NC with EHK. Lesions of NC suspected by clinical exam should be examined microscopically to look for features of EHK. If present, patients should be educated about the risk, albeit rare, of passing on a more severe form of the disorder to subsequent generations.