AL Kappa Amyloidosis with Rapidly Unfavorable Evolution: A Case of Renal, Hepatic, and Muscular Involvement with POEMS Syndrome and Unusual Autoantibody Activity
- Glomerular Diseases: Case Reports
November 02, 2023 | Location: Exhibit Hall, Pennsylvania Convention Center
Abstract Time: 10:00 AM - 12:00 PM
Category: Glomerular Diseases
- 1402 Glomerular Diseases: Clinical, Outcomes, and Trials
- Cazzato, Rossana, Parma University Hospital, Parma, Italy
- Rossi, Giovanni Maria, Parma University Hospital, Parma, Italy
- Greco, Paolo, Parma University Hospital, Parma, Italy
- Maccari, Caterina, Parma University Hospital, Parma, Italy
- Maggiore, Umberto, Parma University Hospital, Parma, Italy
- Fiaccadori, Enrico, Parma University Hospital, Parma, Italy
- Di Mario, Francesca, Parma University Hospital, Parma, Italy
AL amyloidosis arises in the setting of plasma cell discrasia, with deposition of amyloidogenic misfolded immunoglobulin-free light chains in peripheral tissues resulting in progressive organ dysfunction. Involved organs include kidneys, heart, liver, nervous system and gastrointestinal tract.
We report the case of a 61-year-old man who presented with hypotension, alternating diarrhea and constipation, muscle pain, paraesthesias, and a monoclonal IgG kappa component with altered free light chain ratio, nephrotic syndrome and acute kidney injury requiring haemodialysis. After renal and bone marrow biopsies a diagnosis of AL k amyloidosis was reached (Fig. 1). Evidence of persistently elevated levels of liver function tests and creatine phosphokinase led to consideration of amyloid infiltration in the liver and muscle, confirmed by biopsies. Clinical management was complicated by the presence of hypopituitarism associated with MRI changes consistent with hypophysitis. High-titer anti-cardiolipin IgG and anti-β2 glycoprotein IgG was observed, despite the absence of thrombotic lesions on whole-body CT images. The patient was started on a cyclophosphamide-bortezomib-dexamethasone-daratumumab regimen, interrupted after four cycles,following the patient's death only one month after the onset of nephrotic syndrome.
We described a rare case of systemic amyloidosis with a rapidly unfavorable outcome with abrupt disease onset, in which organ involvement has rapidly progressed to multiorgan failure. If we exclude central nervous system involvement, polyendocrinopathies may be explained by concomitant POEMS. The significance of autoantibody positivity in the absence of clinical autoimmunity remains unclear, and raises the suspicion of a false positivity due to molecular mimicry.
Kidney biopsy: (A) Glomerulus and arteriole with amorphous material in mesangial areas and the arteriolar wall respectively stains positive with Congo red and shows apple-green birefringence in polarized light, consistent with amyloid (B).