Systemic amyloidosis with amyloid goiter: An autopsy report

Systemic amyloidosis is a rare but potentially lethal disease characterized by amyloid accumulation in all organs. Amyloid goiter is an extremely rare pathological lesion characterized by thyroid gland enlargement with fat deposition due to local or systemic amyloidosis. A 60 s woman with rheumatoid arthritis was found unconscious on her bed and declared dead after failed cardiopulmonary resuscitation. Postmortem computed tomography showed severe enlargement of the heart and thyroid glands, suggestive of cardiac hypertrophy and thyroidism. Histological examination revealed amorphous eosinophilic deposits with parenchymal cell destruction in all organs, including the heart and thyroid gland. Abnormal amorphous deposits in the tissues were positive for amyloid A as noted upon Congo red immunohistochemical staining and birefringence microscopy, confirming systemic amyloidosis with amyloid goiter. Serum biochemical analysis revealed increased levels of C-reactive protein; anti-cyclic citrullinated peptide antibody; creatinine kinase-myoglobin binding and N-terminal pro-brain natriuretic peptide; and thyroglobulin, free triiodothyronine, and free thyroxine, indicating systemic inflammation, active rheumatoid arthritis, heart failure, and destructive hyperthyroidism, respectively. These findings suggested that the cause of death was undiagnosed heart failure due to secondary systemic amyloid A (AA) amyloidosis related to rheumatoid arthritis. In addition, destructive hyperthyroidism caused by systemic AA amyloidosis may have also been one of the causes of death as indicated by cardiac overload. To the best of our knowledge, this is the first forensic autopsy report of cardiac amyloidosis with amyloid goiter. In conclusion, this autopsy report highlights the importance of increased awareness and early intervention for severe but treatable complications of systemic amyloidosis.