Paraprotein deposits in the skin

Cutaneous manifestations secondary to paraprotein deposits in the skin include a group of different disorders that although rare, may be the first clinical manifestation of the underlying hematologic dyscrasia. In this article we review the clinical manifestations and histopathologic findings of the processes that result from specific deposition of the paraprotein in different structures of the skin. Paraneoplastic processes frequently associated with hematologic malignancies will not be covered in this review. Some of the disorders included here result from deposition of the intact paraprotein in the skin, whereas in other cases the lesions are due to deposition of modified paraproteins in the form of amyloid substance, cryoglobulins, or crystalglobulins. Cutaneous amyloidoma refers to nodular dermal deposits of amyloid derived from immunoglobulin light chains produced by local plasma cells in the absence of systemic amyloidosis. Dermatologists and dermatopathologists should be aware of the clinical and histopathologic features of these rare disorders because sometimes the cutaneous lesions are the first sign of an underlying silent hematologic malignancy with paraproteinemia.

IMAGING DIAGNOSIS-MAGNETIC RESONANCE IMAGING FINDINGS IN A CAT WITH SYSTEMIC REACTIVE ANGIOENDOTHELIOMATOSIS

A 10-year-old, castrated male domestic short-haired cat was presented with an acute history of seizures, lethargy, anorexia, vomiting, and dyspnea. Magnetic resonance imaging of the brain showed multifocal areas of gray matter T2-weighted hyperintensity. The lesions did not enhance with intravenous contrast. The cat was diagnosed at necropsy with feline systemic reactive angioendotheliomatosis, a rare vascular proliferative disorder for which a treatment has not yet been identified. This report is the first to describe associated magnetic resonance imaging changes for this disease.

Graft-versus-host disease-associated angiomatosis: a clinicopathologically distinct entity

BACKGROUND

Chronic graft-versus-host disease (GVHD) may present with various cutaneous manifestations. Isolated case reports describe eruptive angiomas in this setting.

OBJECTIVE

We sought to provide a clinical and pathologic description of vascular proliferations in patients with GVHD.

METHODS

Cases of documented GVHD associated with vascular proliferations were collected from the National Institutes of Health, Ohio State University, and MD Anderson Cancer Center.

RESULTS

Eleven patients with a diagnosis of GVHD who developed vascular proliferations were identified. All patients manifested sclerotic type chronic GVHD of the skin. Vascular lesions were first documented a median of 44 months after transplantation and occurred primarily on the lower extremities or trunk. Histopathology revealed anastomosing networks of thin-walled vascular proliferations in a vague lobular growth pattern, with overlying epidermal acanthosis, peripheral collarette, ulceration, and disorganized fibroblast-rich and fibrotic stroma. Improvement was noted in 1 patient treated with propranolol and sirolimus and 1 patient with electrocautery.

LIMITATIONS

Given the retrospective nature of the study, the overall incidence of vascular lesions in patients with GVHD is unknown. Histopathology was present for review on only 3 of 11 patients.

CONCLUSION

The phenomenon of vascular lesions appears to be relatively specific for sclerotic type chronic GVHD when compared with other fibrosing diseases. We propose the term "graft-versus-host disease-associated angiomatosis" to describe this entity.