Part 3: Diagnosis and Management of Immunoglobulin Light Chain Amyloidosis
Jason S. Starr, DO
Hematology/Oncology Fellow, Division of Hematology and Medical Oncology, Department of Medicine, Mayo Clinic, Jacksonville, FL
Taimur Sher, MD
Assistant Professor of Medicine, Division of Hematology and Medical Oncology, Department of Medicine, Mayo Clinic, Jacksonville, FL
A 48-year-old African American man presents to the emergency department with new-onset slurred speech and weakness of the right upper extremity. A noncontrast computed tomography scan of the head is negative for intracranial bleed, and magnetic resonance imaging with stroke protocol demonstrates acute ischemic stroke in the left middle cerebral artery territory. The patient is started on systemic anticoagulation and aspirin. Four hours after starting anticoagulation, his stroke symptoms resolve. The patient has been previously healthy and works as a fitness trainer. Two-dimensional echocardiogram reveals severe left ventricular systolic dysfunction with an ejection fraction of 40% and sparkling appearance of thickened myocardium and an interventricular septum thickness of 1.6 cm. A transesophageal echocardiogram demonstrates absence of mechanical activity in the left atrium (atrial stand still) and a mural thrombus. Blood work demonstrates normal electrolytes, liver function tests, and complete blood count. Serum protein electrophoresis demonstrates a 1.0 g/dL M-spike identified as IgG lambda on immunofixation electrophoresis. Serum free light chain assay demonstrates lambda light chain levels of 38 mg/dL (normal, <2.6 mg/dL) and a skewed Kappa-lambda ratio. Fat pad aspirate biopsy demonstrates congophilic amyloid material. Bone marrow biopsy demonstrates 10% lambda restricted plasma cells. Cardiac biomarkers are indicative of stage III disease. Mass spectrometry confirms the amyloidosis as AL. Clinical and biochemical assessment indicates cardiac involvement only.
What is the best management plan for this patient?