Biophysical and Ultrasonographic Findings of Cutaneous Macular Amyloidosis Lesions in Comparison With Uninvolved Skin

Macular amyloidosis (MA) is a primary localized cutaneous amyloidosis (PLCA), characterized by amyloid deposition in the papillary dermis. The goal of this study was to compare biophysical characteristics in MA lesions with uninvolved skin. Stratum corneum (SC) hydration, transepidermal water loss (TEWL), surface friction, pH, sebum, melanin, erythema, temperature, elasticity parameters (R0, R2, and R5), thickness, and echo-density of epidermis and dermis were measured on the active MA lesions in 22 patients and compared with the healthy area adjacent to the lesion as control. Paired t-test was used for statistical analyses, and a p < 0.05 was considered significant. SC hydration, skin friction were significantly lower, whereas TEWL, pH, erythema index, melanin content, and the thickness of epidermis were significantly higher in MA lesions. There was no significant difference in other biophysical and ultrasonographic parameters between MA and normal skin. MA lesions are characterized by specific changes in ultrasonographic and biophysical parameters, compatible with their histological features. These charachteristics are likely to be useful in the early and noninvasive detection of cutaneous MA in the future.