Friction-Induced Biphasic Cutaneous Amyloidosis

Primary cutaneous amyloidoses (PCA) are a group of conditions characterized by deposition of amyloid in previously normal skin, without association with other skin or systemic diseases. We describe a Kazakhstani female with a 30-year history of increasingly spreading hyperpigmented macular as well papular skin lesions on her upper trunk accompanied by pruritus. Moreover, her medical history included intensely rubbing her skin with a cotton towel following bathing and showering. On the basis of the clinical and histopathological findings, the diagnosis of biphasic cutaneous amyloidosis was made. The present unusual case of biphasic cutaneous amyloidosis can be subsumed under mechanically-induced forms of cutaneous amyloidosis. In conclusion, the present case underscores the necessity to explore carefully the patient’s history in order to discover the cause of PCA.