MR of the kidneys, liver, and spleen in paroxysmal nocturnal hemoglobinuria

Abstract

The magnetic resonance (MR) findings in the liver, kidneys, and spleen in eight patients with paroxysmal nocturnal hemoglobinuria (PNH) were retrospectively reviewed to determine whether characteristic features could be demonstrated. Eight patients underwent abdominal MR examinations by gradient echo sequences (seven patients), spin-echo sequences (seven patients), and inversion recovery (one patient). Signal intensities of the kidneys, liver, and spleen were visually evaluated. Autopsy and liver biopsy correlation were available in one case each. Renal signal intensity was decreased in all eight patients by either gradient-echo or T2-weighted sequences and in the single inversion recovery sequence. Hepatic signal intensity was decreased in three of eight patients on spin- and gradient-echo images. Splenic signal intensity was decreased in three of eight patients on spin- and gradient-echo images, and in two of these was manifest as focal low signal spots (Gamna-Gandy bodies). While the signal intensity in the renal cortex is typically decreased in patients with PNH, signal intensities in the liver and spleen are variable. Low signal intensity in the kidneys is due to hemosiderin deposition resulting from intravascular hemolysis, whereas low signal intensity in the liver or spleen may be due to either transfusion siderosis, or as a consequence of hepatic or portal venous thrombosis.

MR Imaging Findings of Iron Overload

“…In these cases, hemosiderin is deposited in the proximal convoluted tubules, promoting inversion of the signal intensity of the renal cortex, which is hypointense in relation to the medulla on the T1-weighted images and demonstrates an accentuated decrease in the cortical signal intensity on the T2-weighted images (32)(33)(34). Despite the dramatic appearance of this type of accumulation, it is not believed that this accumulation affects renal function (8,31,35) (Fig 10).…”

“…Iron deposition in the kidneys is only seen in cases of intravascular hemolysis caused by mechanical stress in patients with heart valves, in patients with paroxysmal nocturnal hemoglobinuria, or in hemolytic crises of sickle cell disease (8,(31)(32)(33)(34). In these cases, hemosiderin is deposited in the proximal convoluted tubules, promoting inversion of the signal intensity of the renal cortex, which is hypointense in relation to the medulla on the T1-weighted images and demonstrates an accentuated decrease in the cortical signal intensity on the T2-weighted images (32)(33)(34).…”

Composition and significance of splenic Gamna-Gandy bodies in sickle cell anemia

“…Other conditions, apart from chronic hemolysis, have been associated with GGB splenic involvement: leukemia [10], syphilis [11], portal hypertension [12,13], paroxysmal nocturnal hemoglobinuria [14], angiosarcoma [15], SCA [16,17], and lymphoma [18,19].…”

Paroxysmal nocturnal hemoglobinuria in a girl with hemolysis and ?hematuria?

“…Due to a decreased cortical intensity, corticomedullary differentiation will be reversed on T1-weighted images in renal cortical hemosiderosis. Since iron also shortens the T2 relaxation time, cortical intensity will also be very low on T2-weighted images [17,18].…”