Extensive Variant of Cutaneous Amyloidosis: Report of a Case with Electron-Microscopic and Immunohistochemical Studies of the Basement Membrane Zone at Sites of Amyloid Production

Abstract

A 60-year-old Japanese female developed widespread lichenoid eruptions with pigmentation, which initially appeared in preceding erythematous skin lesions due to dermatomyositis. Thioflavine T and Dylon stainings, electron microscopy and immunohistochemistry revealed that thick amyloid deposits were present in the papillary dermis particularly beneath the epidermis. Autopsy showed no evidence of systemic amyloidosis. Electron microscopy of the lesional skin disclosed the disturbance of lamina densa formation in the epidermal basement membrane zone (BMZ). There was disruption and dissociation of the lamina densa from the basal cell, and a lamina-densa-like substance was found in the amyloid deposits. Immunofluorescence and immunoelectron microscopy showed that type IV and VII collagens, LDA-1 antigen (a noncollagenous component of the BMZ) and laminin were distributed in irregular thick deposits along the BMZ and were also present within the amyloid itself. These findings indicate that morphological and immunohistochemical abnormalities of the lamina densa may be involved in amyloid production at the interface of the epidermis and dermis, at least in this case.

Keratinocyte‐derived amyloidosis as a manifestation of chronic graft‐versus‐host disease

“…Amyloid deposition has only been rarely reported in association with one of the most common forms of interface dermatitis, namely lichen planus . Similarly, amyloid deposition has been documented as an exceptional finding in the context of dermatomyositis or keratosis lichenoides chronica . Based upon such reports and also the case reported here, it seems clear that inflammation focused on the epidermal‐dermal junction plays a key role in the etiopathogenesis of keratinocyte‐derived amyloidosis.…”

“…11 Similarly, amyloid deposition has been documented as an exceptional finding in the context of dermatomyositis or keratosis lichenoides chronica. 12,13 Based upon such reports and also the case reported here, it seems clear that inflammation focused on the epidermal-dermal junction plays a key role in the etiopathogenesis of keratinocytederived amyloidosis. Per a mechanism postulated over three decades ago, an interface process damages keratinocytes, which then drop into the dermis.…”

Cutaneous Amyloidosis Associated with Amyopathic Dermatomyositis

“…It is uncommon that cutaneous amyloidosis occurs in patients with DM [4][5][6] . A search of the PubMed database identified only 3 cases of patients with DM associated with cutaneous amyloidosis [4][5][6] .…”

“…A search of the PubMed database identified only 3 cases of patients with DM associated with cutaneous amyloidosis [4][5][6] . Previous reports described that the duration from the onset of eruption to the diagnosis of cutaneous amyloidosis by skin biopsy was approximately 10 years [4][5][6] . In patients with DM, cutaneous amyloidosis might be based on chronic inflammation.…”

Localized cutaneous immunoglobulin light chain kappa‐positive amyloidosis associated with juvenile dermatomyositis

“…Only three cases of patients with dermatomyositis associated with cutaneous amyloidosis have been identified in studies published in English. [3][4][5] Orihara et al 3 reported that the duration from the onset of eruption to the diagnosis of cutaneous amyloidosis by skin biopsy was 15 years. In patients with dermatomyositis, cutaneous amyloidosis may be based on chronic inflammation and is believed to be derived from the epidermis because of positive anti-keratin antibody staining.…”