Cutaneous amyloid elastosis revealing multiple myeloma with systemic amyloidosis

A Second Case of Localized Cutaneous Amyloid Elastosis: Expanding the Discussion of Associations With a Unique Histopathologic Entity

ABSTRACT

Amyloid elastosis is an exceedingly rare form of amyloidosis characterized by amyloid material deposited on dermal elastic fibers. Most reported cases have been associated with systemic amyloid light-chain amyloidosis. A single previously reported case of amyloid elastosis showed evidence that the amyloid material was derived from light-chain proteins and was associated with a monoclonal plasma cell infiltrate but failed to demonstrate systemic involvement. As a result, the case was felt to represent localized cutaneous amyloid elastosis. We present a case of localized cutaneous amyloid elastosis that is not associated with a definitive monotypic plasma cell population or with systemic amyloidosis. We also review the clinical and histopathologic features of reported cases of amyloid elastosis and discuss possible etiologic considerations. Because amyloid elastosis can be either localized to the skin or associated with systemic involvement, additional workup to exclude an underlying plasma cell dyscrasia or hematologic malignancy is warranted.

Severe elastolysis in hereditary gelsolin (AGel) amyloidosis

AGel amyloidosis is a dominantly inherited systemic amyloidosis caused by mutations p.D214N or p.D214Y resulting in gelsolin amyloid (AGel) formation. AGel accumulates extracellularly in many tissues and alongside elastic fibres. AGel deposition associates with elastic fibre degradation leading to severe clinical manifestations, such as cutis laxa and angiopathic complications. We analysed elastic fibre pathology in dermal and vascular tissue and plasma samples from 35 patients with AGel amyloidosis and 40 control subjects by transmission electron microscopy, immunohistochemistry and ELISA methods. To clarify the pathomechanism(s) of AGel-related elastolysis, we studied the roles of MMP-2, -7, -9, -12 and -14, TIMP-1 and TGFβ. We found massive accumulation of amyloid fibrils along elastic fibres as well as fragmentation and loss of elastic fibres in all dermal and vascular samples of AGel patients. Fibrils of distinct types formed fibrous matrix. The degradation pattern of elastic fibres in AGel patients was different from the age-related degradation in controls. The elastin of elastic fibres in AGel patients was strongly decreased compared to controls. MMP-9 was expressed at lower and TGFβ at higher levels in AGel patients than in controls. The accumulation of amyloid fibrils with severe elastolysis characterises both dermal and vascular derangement in AGel amyloidosis.

[Multifocal chalazodermic amyloidosis: The concept of immunoglobulinemic elastopathy]

INTRODUCTION

Impairment of dermal elastic tissue occurs in different entities associated with immunoglobulins or immunoglobulin-derived protein-secreting clonal plasma cell proliferations, such as amyloid elastosis, anetodermic nodular amyloidosis or monoclonal gammopathy-associated cutis laxa. We report a case of cutaneous immunoglobulinemic amyloidosis revealed by a unique chalazodermic presentation and we review elastic tissue impairment in patients with monoclonal gammopathies.

OBSERVATION

A 67-year-old woman consulted for non-infiltrated anetodermic lesions on the upper left quadrant of her abdomen present for ten years. She also had a chalazodermic plaque with abnormal skin wrinkling and laxity in her right axilla. Biopsies revealed deep dermal and subcutaneous amyloid deposits. Immunohistochemistry with lambda light chain was positive. Orcein staining and electron microscopy showed extensive elastolysis. The patient presented no signs of systemic involvement, but a very small amount of monoclonal IgGλ gammopathy was detected during follow-up.

DISCUSSION

This is a unique chalazodermic presentation of immunoglobulinemic amyloidosis that does not fit into a clearly-defined nosological setting. It highlights the complex interactions between immunoglobulin-derived proteins, including light and heavy chains, and elastic tissue components, leading to different types of impairment of the latter. We therefore suggest the unifying concept of immunoglobulinemic elastopathy, underscoring the need to screen for monoclonal gammopathy in patients presenting elastic tissue impairments.

Restrictive cardiomyopathy and pseudoxanthoma elasticum skin lesions

: We report a rare case of a patient with AL amyloidosis and pseudoxanthoma elasticum skin lesions. An association between these two diseases has been previously described as amyloid elastosis in only six cases, but cardiac findings were not fully elucidated. The peculiarity of our case is that a severe cardiac involvement influenced the prognosis negatively. Furthermore, the electron microscopic examination did not show all the peculiar histopathological findings of amyloid elastosis, precluding a final diagnosis of this disease.