Abstract
A 73-year-old Japanese man was admitted with heart failure due to AL amyloidosis caused by left ventricular hypertrophy and IgA-kappa monoclonal gammopathy. However, endomyocardial biopsy revealed eosinophilic amorphous material in the myocardium, which was positive for Congo red staining and transthyretin (TTR), but negative for the kappa chain. The patient was diagnosed with wild-type amyloid TTR (ATTR) amyloidosis and monoclonal gammopathy of uncertain significance. Among the different types of amyloidosis including AL amyloidosis (primary amyloidosis from an abnormality of plasma cells), AA amyloidosis (secondary amyloidosis in association with chronic inflammatory disease), and dialysis-related amyloidosis (deposition of beta-2 microglobulin), ATTRwt amyloidosis is a slowly progressive disease that affects most commonly the hearts of elderly in elderly patients who sometimes have other diseases. Thus, pathological examination is important for the diagnosis of amyloidosis.
