gms | German Medical Science

Cerebral amyloid angiopathy (CAA) is characterized by the deposition of amyloid in leptomeningeal and cerebral blood vessels leading to hemorrhage. The proteins deposited as amyloid in CAA are different, that is Aβ-protein in CAA is seen mostly in Alzheimer’s disease and familial Dutch apoplexia, but also in CAA sui generis, cystatin C is seen in hereditary Islandic apoplexia and transthyretin in familial amyloid angiopathy. CAA can be sporadic or inherited, the latter is induced by point mutations which increase the amyloidogenic potential of the amyloid-precursor protein. This report describes a very rare disease since the protein is different from tnose already published.

A 55-year old woman without family history of dementia and neurological disease perceived increasing memory loss more than nine years ago. Worsened mental and neurological status with dementia, global aphasia, affect incontinence, severe apraxia, ataxia, bilaterally negative Achilles-reflexes and positive signs of Babinsky, as well as incomplete orientation were observed. The patient became somnolent and had a left-sided hemiparesis. Cranial computer tomography revealed a subacute subdural hematoma over the right hemisphere with mass effect and unusual intracranial calcifications which made surgery necessary. Immediate decompressive surgery indicated that bleeding originating from calcified blood vessels. In addition, brain atrophy was noticed. The patient recovered postoperatively well and was discharged to a rehabilitation facility. Blood vessels of the cortical biopsy revealed massive local amyloid deposition. Surrounding brain tissue was focally degenerated. In addition, calcification and bone formation were noticed while skin biopsy did not show any amyloid. Immunohistochemical classification diagnosed the presence of ALλ amyloid while such other amyloid classes as AA, ALκ, AHγ, Aβ₂M, ATTR, AFib, AApoAI, AApoAII, ALys, Aβ, and ACys were excluded.

An intracerebral monoclonal gammopathy with Ig-λ-light chain synthesis is the cause of intravascular ALλ amyloid. This amyloid is brain-restricted since systemic amyloidosis is absent. A case like thishas not been published before.