Efficacy of hepatic computed tomography to detect iron overload in chronic hemodialysis

Abstract

The diagnostic efficacy of hepatic computed tomography density (HCTD) in comparison with serum ferritin for the detection of iron overload was investigated in uremic patients on maintenance hemodialysis (HD) and in patients with idiopathic hemochromatosis (IHC). Ten IHC patients, 38 HD patients and 40 healthy subjects underwent the CT scanning of the liver and determination of percent saturation of transferrin, serum ferritin concentration and HLA typing. Liver iron content was determined by histochemical grading and direct measurement of liver iron concentration either in IHC patients or in HD patients. Nineteen HD patients were considered to have iron overload on the basis of liver iron concentration exceeding 3.6 mumol/100 mg dry weight. The mean +/- SD values of HCTD in healthy subjects, IHC patients, HD patients with iron overload and without iron overload were 60.2 +/- 5.6, 79 +/- 5.6, 71.4 +/- 3.6, 58 +/- 3.8 Hounsfield units, respectively. HCTD showed positive correlations with liver iron concentration and serum ferritin either in IHC patients or in HD patients. The analysis of the diagnostic efficacy of HCTD in comparison with serum ferritin for the detection of excessive hepatic iron in HD patients demonstrated that HCTD had higher sensitivity, specificity, positive and negative predictive values. Cut-off points were arbitrarily fixed to 66 Hounsfield units for HCTD, 400 micrograms/liter for serum ferritin and 3.6 mumol/100 mg dry weight for liver iron concentration. Seventeen HD patients who possessed the histocompatibility antigens associated with IHC, namely HLA-A3 and/or HLA-B7 and/or HLA-B14, had liver iron concentration, serum ferritin and HCTD values higher than those of the HD patients without these "hemochromatosis alleles".(ABSTRACT TRUNCATED AT 250 WORDS)

Radiological features of the visceral and skeletal involvement of hemochromatosis

“…Iron excess in the liver parenchyma causes an increase in CT attenuation of the liver [2][3][4][5][6]. The characteristic radiological finding is a "white liver" in unenhanced CT scans with a diffuse increase in liver density above 70 HU (Fig.…”

Iatrogenic iron overload and its potential consequences in patients on hemodialysis

“…The advent of recombinant human erythropoietin in the early 1990s represented a therapeutic revolution which allowed anemia and iron overload to be treated simultaneously by inducing both massive mobilization of iron stores and effective phlebotomy by partial letting of the extracorporeal circuit at the end of the dialysis sessions in patients who had been rendered nonanemic [47]. The same period saw the first successful use of quantitative computed tomography, the first noninvasive radiological tool, for the diagnosis of hemodialysis-associated hemosiderosis and for monitoring liver iron stores [48]. The full-blown clinical picture of hemodialysis-associated hemosiderosis disappeared from dialysis centers in industrialized countries at least 3 decades ago but may still occur in emerging countries where ESAs are not available [3].…”

Iatrogenic Iron Overload in Dialysis Patients

“…At the beginning of the 1990s, the advent of recombinant human erythropoïetin allowed simultaneous treatment of anemia and iron overload by allowing massive mobilization of iron stores and effective phlebotomy (by partial letting of the extracorporeal circuit) at the end of dialysis sessions in patients rendered non anemic [34], together with the first successful use of non invasive radiological tools (liver quantitative computer tomography) to diagnose hemodialysis-associated hemosiderosis and to monitor iron stores [35].…”