Characteristic Dermoscopic Features of Primary Cutaneous Amyloidosis

A Study of 35 Cases

Y.Y. Chuang; D.D. Lee; C.S. Lin; Y.J. Chang; M. Tanaka; Y.T. Chang; H.N. Liu


The British Journal of Dermatology. 2012;167(3):548-554. 

In This Article

Materials and Methods

This study was approved by the Institutional Review Board of Taipei Veterans General Hospital, Taipei, Taiwan. Participants were enrolled from the Outpatient Dermatology Clinics of Taipei Veterans General Hospital from July to December of 2010. Informed consent was obtained. Previous history of Er:YAG or carbon dioxide laser dermabrasion to treat PCA was the only exclusion criteria. Only patients with typical clinical presentations of PCA, either macular or lichen subtypes, were included in this study. All were evaluated using a hand-held, polarized and nonpolarized dermoscope (DermLite II hybride; 3Gen LLC, Dana Point, CA, U.S.A.), with a photographic lens attachment. The dermoscopic images were taken by a 3·34 megapixel digital camera (Nikon Coolpix 995; Nikon Corp., Tokyo, Japan), which was connected directly to the dermoscope. We used 70% alcohol as the interface liquid to eliminate the effect of excessive keratin.[11] The contact polarized mode of the dermoscope was used for observation.[12] One case of friction melanosis and one of lichen simplex chronicus were evaluated with the same dermoscope for comparison.

Although the diagnoses of PCA of the patients were made based on their typical clinical pictures, each patient was given an option to undergo skin biopsy. The specimen was stained with haematoxylin and eosin, crystal violet or Congo red for pathological confirmation. Positive cases are defined by masses of eosinophilic, amorphous fissured material in the papillary dermis, which shows metachromasia for crystal violet or Congo red.[13,14]