Renal hemosiderosis secondary to intravascular hemolysis after mitral valve repair: A case report

RATIONALE

Renal hemosiderosis is a disease in which hemosiderin deposits in the renal cortex as a form of iron overload. However, cases of renal hemosiderosis due to intravascular hemolysis following mitral valve repair have been rarely reported.

PATIENT CONCERNS

We present the case of a 62-year-old woman who developed asymptomatic urinary abnormalities including microscopic hematuria and proteinuria due to renal hemosiderosis following a mitral valve repair surgery performed two years earlier.

DIAGNOSES

A percutaneous renal biopsy showed no specific glomerular abnormality, tubular atrophy, or interstitial fibrosis but extensive deposition of hemosiderin in the proximal tubule. The patient was diagnosed with renal hemosiderosis and chronic intravascular hemolysis following mitral valve repair.

INTERVENTIONS

Our patient refused a mitral valve repeat surgery and hence was treated with oral iron preparations, N-acetylcysteine, and a β-receptor blocker.

OUTCOMES

Moderate mitral regurgitation with the regurgitant blood striking against the annuloplasty ring was confirmed on follow-up echocardiography. After the 24-month follow-up period, hemolytic anemia persisted, but there was no significant decline of renal function.

LESSONS

For cases of chronic intravascular hemolysis accompanied with asymptomatic urinary abnormalities, a renal biopsy is required to exclude underlying kidney pathology and predict potential renal insufficiency.

Acute Kidney Injury by Renal Hemosiderosis Secondary to Primary Cold Agglutinin Disease Associated with an Excessive Alcohol Intake

Renal hemosiderosis occurs in the context of severe intravascular hemolysis, with the most common cause being paroxysmal nocturnal hematuria. Patients with cold agglutinin disease (CAD) have relatively mild hemolysis, and acute kidney injury (AKI) due to renal hemosiderosis has not been reported. We encountered a patient with CAD caused by lymphoplasmacytic lymphoma who developed AKI secondary to renal hemosiderosis after an excessive alcohol intake.