Bronze Diabetes

Diabetes mellitus recently had been diagnosed in a 58-year-old woman. The patient claims that her skin had darkened significantly over the past 5 years.

Hepatomegaly was noted; there was no splenomegaly or lymphadenopathy. An ECG disclosed extrasystoles. Abdominal ultrasound confirmed liver enlargement but no focal abnormalities.

The patient's hematocrit was 48%; hemoglobin, 16.3 g/dL; mean corpuscular volume, 92 fL; mean corpuscular hemoglobin, 30 pg; white blood cell count, 7.4 × 10⁹/L; and platelet count 190 × 10⁹/L. Other test results included fasting serum glucose level of 195 mg/dL; aspartate aminotransferase, 61 U/L (normal range: 0 to 40 U/L); alanine aminotransferase, 74 U/L (normal range: 0 to 40 U/L), and γ-glutamyltransferase, 82 U/L (normal range: 0 to 48 U/L).

Levels of serum alkaline phosphatase, total and direct bilirubin, lactic dehydrogenase, total proteins, albumin, serum creatinine, urea electrolytes, and thyroid-stimulating hormone, and the international normalized ratio were within normal limits. However, levels of serum iron (340 µg/dL), total iron binding capacity (185 µg/dL), and serum ferritin (1,250 µg/L) were abnormal.

Drs Haralampos Milionis, George Liamis, and Moses Elisaf of Ioannina, Greece, report that the histopathologic examination of a liver biopsy specimen was consistent with hemochromatosis. Because primary hemochromatosis results from an autosomal recessive trait, the patient's first-degree relatives were screened; none were found to have elevated serum ferritin levels.

Therapy with oral hypoglycemic agents was initiated, and phlebotomy was performed twice weekly, with 500 mL of blood removed at each treatment. Three months later, the patient's ferritin levels had dropped to 750 mg/L, the liver function tests remained unchanged, and no significant change in skin color was noted.

Diet modifications and a sulfonylurea were prescribed for the patient's diabetes.