Rheumatic heart disease associated with secondary renal amyloidosis

ABSTRACT

Amyloidosis is a disorder of protein folding in which normally soluble proteins undergo conformational changes and are deposited in the extracellular space in an abnormal fibrillar form. Accumulation of these fibrils causes progressive disruption of the structure and function of tissues and organs, and the systemic forms of amyloidosis are frequently fatal. The conditions that underlie amyloid deposition may be either acquired or hereditary. Amyloid-A [AA] amyloidosis is the most common form of systemic amyloidosis worldwide, AA amyloidosis occurs in the course of chronic inflammatory diseases, hereditary periodic fevers, and with certain neoplasms such as Hodgkin disease and renal cell carcinoma. Amyloidosis due to rheumatic heart disease [RHD] is not common but can be seen. We report here a patient with RHD and AA renal amyloidosis. We present a 30 year-old Egyptian male with a history of RHD, accidently discovered to have nephrotic range proteinuria and rising serum creatinine. Serology studies were negative or normal, including antinuclear antibody [ANA] and antineutrophil cytoplasmic antibody [ANCA]. C3 and C4 complement levels were normal. Kidney biopsy revealed AA renal amyloidosis. CT chest and abdomen revealed bilateral hilar and mediastinal lymphadenopathy and para-aortic lymph nodes. Endobronchial biopsy and bronchoalveolar lavage revealed non-specific chronic inflammatory changes. The patient's secondary amyloidosis was presumed to be related to the long standing RHD after exclusion of other causes of secondary amyloidosis. The patient finally died due to heart failure and acute pulmonary edema. Long standing RHD can lead to secondary AA amyloidosis