Usefulness of Biochemical Screening of Diabetic Patients for Hemochromatosis

Abstract

We assessed the prevalence of previously unrecognized hemochromatosis among patients in whom diabetes mellitus was diagnosed after the age of 30 yr, and we evaluated the positive predictive value of biochemical screening tests for hemochromatosis in diabetic subjects. Thirty-eight of 572 patients screened (6.6%) had a serum ferritin level greater than 324 micrograms/L; 16 patients had normal levels on repeat testing. Four patients' serum ferritin levels fell to less than 400 micrograms/L. Seven of 18 patients with a persistently elevated serum ferritin level did not undergo a liver biopsy because of a recognized cause of hyperferritenemia (carcinoma, alcoholism, or systemic lupus erythematosus). The diagnosis of hemochromatosis seemed certain in 1 of 3 patients who were not biopsied for technical reasons. Of 8 patients biopsied, 2 had hemochromatosis, 4 had fatty liver, 1 had hemosiderosis, and 1 had a chronic inflammatory cell infiltrate with no iron deposition. Of 4 patients with a raised transferrin saturation level, 2 had raised serum ferritin levels and hemochromatosis, 1 had raised serum ferritin and hemosiderosis on liver biopsy, and 1 had a normal transferrin saturation level on repeat testing. Two of 3 cases of hemochromatosis had other clinical markers of the condition. Therefore, routine screening of diabetic patients for hemochromatosis is not necessary, because patients with hemochromatosis will often have other clinical features of the disease. When screening diabetic patients for hemochromatosis, it should be remembered that a persistently raised serum ferritin level has a low positive predictive value (16.6%) and that a normal transferrin saturation level does not exclude the diagnosis.

Screening for Hemochromatosis in Routine Medical Care: An Evaluation of Mean Corpuscular Volume and Mean Corpuscular Hemoglobin

“…However, the PV 1 of a single transferrin saturation test was 41% in persons with liver disease (Bell et al, 1994). In patients with diabetes mellitus, PV 1 of initial and repeat transferrin saturation testing were 63% and 80%, respectively, when elevated hepatic iron stores were used as the standard case definition (O'Brien et al, 1990;George et al, 1995;Conte et al, 1998). Taken together, these observations indicate that the PV 1 of MCV or MCH testing is less than that of transferrin saturation testing.…”

“…The prevalence of hem ochromatosis is greater in persons receiving testing or treatment for conditions associated with complications of iron overload than in the general population or in blood donors (Witte et al, 1996;Cogswell et al, 1998;Niederau et al, 1998). For example, hem ochromatosis occurred in 3.4-4.6% of white persons undergoing percutaneous liver biopsy (Adams et al, 1991;Barton et al, 1996), 1.2-3.5% of persons in a rheumatology clinic (Olynyk et al, 1994), and 0.5-1.0% of persons attending diabetes clinics (Phelps et al, 1989;O'Brien et al, 1990;George et al, 1995). Using a hemochrom atosis frequency of 1.5% and MCV cut-off points $ 101.0 fL, we obtained PV 1 values of 8.8-100.0% in men and 100.0% in women with maximum sensitivity values of 24.1% and 25.0%, respectively.…”

Der hepatogene Diabetes – aktueller Stand der Diagnostik und Therapie

“…Die Bestimmung des HbA 1c ist bei Leberzirrhose daher nicht verläss-lich und als Verlaufsparameter für die Effizienz einer antidiabetischen Therapie nur eingeschränkt geeignet [13,74]. Dies muss vor allem bei Hämochromatose-Patienten mit Diabetes mellitus beachten werden, welche einer regelmäßigen Aderlasstherapie unterzogen werden [53]. Methoden zur Bestimmung der Insulinsensitivität, z.…”

Hereditary hemochromatosis: Perspectives of public health, medical genetics, and primary care

“…The incidence of hemochromatosis is greater in the clinically defined group than in the general population; with the above caveats, this reasoning would support testing for HHC in relatives of affected patients, but screening studies among diabetics in clinical settings to date have been inconsistent 52,[57][58][59][60][61][62] and the prevalence of HHC among patients with nonspecific symptoms appears low. 54 …”