The role of transferrin saturation as a screening test for hereditary haemochromatosis in an Irish population seeking medical care

Traditional home-brewed beer consumption and iron status in patients with esophageal cancer and healthy control subjects from Transkei, South Africa

Consumption of home-brewed beer is associated with dietary iron excess and a high incidence of esophageal cancer in Transkei, South Africa. We examined the relationship between home-brewed beer consumption and body iron status in 234 patients with esophageal squamous cell carcinoma and 595 control subjects residing in Transkei. Subjects were screened for iron overload using transferrin saturation >45%, and/or serum ferritin >200 microg/l for women and >300 microg/l for men. A questionnaire was administered to all subjects, and iron content of randomly selected home-brewed beer samples was determined. The iron content of home-brewed beer was 258-fold higher than the commercial Castle Lager beer produced by South African Breweries. The prevalence of home-brewed beer consumption was 30.1% in esophageal cancer patients and 15.5% in control subjects and was found not to be a risk factor for esophageal cancer after adjustment for age, sex, and tobacco consumption (male subjects, odds ratio= 1.6 (95% confidence interval [CI]: 0.7-4.5); female subjects, odds ratio=1.7 (95% CI: 0.7-4.5). Iron overload as determined by transferrin saturation and elevated serum ferritin was observed in 4.3% of patients with esophageal cancer and 0.7% of control subjects and was not associated with the consumption of home-brewed beer. Consumption of home-brewed beer is not a risk factor for esophageal cancer and is not linked with iron overload in either cancer patients or control subjects; however, iron overload is likely to result from a combination of dietary intake and a genetic component.

Comparison of serum iron, total iron binding capacity, ferritin, and percent transferrin saturation in nine species of apparently healthy captive lemurs

Lemurs kept in captivity have been reported to be highly prone to accumulate excessive amounts of iron in tissues (hemosiderosis). Diagnosis of the condition is most commonly made during a postmortem examination because an antemortem diagnosis requires a liver biopsy, a procedure that may not be well tolerated by all animals. The lack of a noninvasive method to evaluate iron status in captive lemurs limits investigators' ability to effectively screen animals for the presence of hemosiderosis, and to detect the condition early when treatment protocols are most effective. This study was conducted in an effort to provide data regarding iron analyte values in healthy captive lemurs of multiple species. The relationship of various iron-related metabolites was evaluated in 177 clinically normal lemurs of nine different species. Serum iron (sI), total iron binding capacity (TIBC), and ferritin concentration were measured directly and the percent transferrin saturation (TS) was calculated. Significant differences in various iron metabolites were observed among several species, suggesting that normal reference values for iron metabolites in lemurs may need to be developed on a species by species basis.

Increased iron absorption in lemurs: Quantitative screening and assessment of dietary prevention

Iron storage disease (ISD) in lemurs has been reported since as early as the 1960s, and in the 1980s was demonstrated to be a consistent finding in postmortem investigations of captive lemurs. Since then this disease has consistently been diagnosed at the point of necropsy. In the current study we describe a preclinical screening procedure, as well as the quantified preventive effects of dietary intervention upon iron absorption. Twenty-three individual lemurs of four species were initially tested with the transferrin saturation test (%TS); 21 of these animals were on conventional zoo diets, and two were fed a specific diabetic diet. Initially, 20 of 21 lemurs on conventional zoo diets were demonstrated to have %TS levels above the normal range for humans; 17 of these lemurs were in the category (for humans) of excessive iron absorption. A dietary change aimed at reducing dietary iron and vitamin C levels and increasing the levels of iron-chelating tannins and/or phytates was instigated. After the animals were retested, a matched-pair comparison of %TS values before and after the diet change revealed significantly (P=0.038, n=7) lower %TS values after the diet change. All species averages were in the human hyperabsorption range on conventional zoo diets (n=21). No species averages were in that range after the dietary change (n=18). The results indicate that further investigations into the use of %TS testing in lemur husbandry, and specific preventive dietary measures, should be conducted.