Amyloidosis Cutis Dyschromica, a Rare Cause of Hyperpigmentation: A New Case and Literature Review

Abstract

Amyloidosis cutis dyschromica is a rare form of primary cutaneous amyloidosis without systemic involvement and characterized by asymptomatic, progressive hyper- and hypopigmentation. We present the first case of a patient with amyloidosis cutis dyschromica diagnosed previously elsewhere as having Addison disease with generalized hyperpigmentation of the skin. This case suggests that in patients presenting with asymptomatic cutaneous dyschromia a skin biopsy for histopathological examination should be considered.

Familial Mottled Pigmentation: Answer

“…Amyloidosis cutis dyschromica (ACD) is a rare type of primary cutaneous amyloidosis with distinct clinical and pathologic features. 1,2 There are reports of familial aggregations in the literature. 3,4 Etiology of ACD is still largely unknown.…”

“…The early onset before puberty and the presence of familial cases are highly suggestive of a genetic base. 2 Genetic factors causing defect in DNA repair following ultraviolet rays leading to apoptosis of keratinocytes had been proposed. These apoptotic keratinocytes give rise to the amyloid globules in papillary dermis.…”

Case Report: Amyloidosis Cutis Dyschromica: Dermoscopy and Reflectance Confocal Microscopy and Gene Mutation Analysis of a Chinese Pedigree

“…Primary localized cutaneous amyloidosis (PLCA) is a group of chronic pruritic skin diseases characterized by amyloid deposits in the upper dermis. Amyloidosis cutis dyschromica (ACD) is a rare type of PLCA first described by Morishima in 1970 ( 1 ). In 2018, mutations of the glycoprotein non-metastatic melanoma protein B ( GPNMB ) were proven to be associated with ACD ( 2 ).…”

Amyloidosis cutis dyschromica treated with acitretin. A case report

“…keratolytics, capsaicin, and CO 2 laser. 3,4,6 Routine use of sunscreen is recommended by consensus. 7 Acitretin has produced promising results in a few cases, 8,9 hence our treatment choice.…”