Israel Medical Association Journal

Background: Genetic hemochromatosis leads to iron overload in many tissues and may lead to liver cirrhosis and hepatocellular carcinoma. Early diagnosis and therapy are crucial. Since 80–100% of hemochromatosis patients of European origin are homozygous for a cysteine to tyrosine exchange in the HFE gene at codon 282, genetic screening might be useful. Representative population studies are needed to evaluate the phenotype of people heterozygous and homozygous for the C282Y mutation.

Objective: To determine the correlation between parameters of iron metabolism and the hemochromatosis genotype in a large population-based study.

Methods: A representative population-based survey, the Diabetomobil study, analyzed 5,083 German probands. Serum transferrin saturation and ferritin levels were determined, and the C282Y mutation of the HFE gene was analyzed by restriction fragment length polymorphism- polymerase chain reaction analysis.

Results: Nine of 373 probands with a transferrin saturation > 55% (2.4%) and none of 264 randomly selected probands with a transferrin saturation £ 55% (0%) were homozygous for the C282Y mutation. Three of the nine homozygous probands had ferritin values less than 250 µg/L. The frequency of the heterozygous genotype was 8.8%, and the percentage of heterozygous probands increased with increasing levels of transferrin saturation.

Conclusion:We propose a population screening strategy with an initial transferrin saturation test, followed by genotyping for the C282Y mutation if the transferrin saturation is above 55%, regardless of the ferritin level. Heterozygous individuals with higher transferrin saturation values may be protected against iron loss but may also be more susceptible for certain liver diseases, depending on the simultaneous prevalence of other diseases.
 

Background: Fasting is required by the Jewish and Islamic religions, and may sometimes be necessary for non­religious reasons as well. Very little empiric data are available on the effect of 24 hours of food and water deprivation.

Objectives:  To compare the effects of the dietary composition of different pre-fast meals on subjective discom­fort and various other parameters of a 24 hour food and water fast.

Methods: Thirteen volunteers of both genders participated in a non-randomized crossover study. Each consumed three different equicaloric pre-fast meals in which the main source of calories was protein (49% of calories), carbohydrate (86%), or fat (69%). Weight, heart rate, blood pressure, blood and urine were tested before and after 24 hours of fasting, and the subjective evaluations of the discomfort during the three fasts were compared.

Results: After the protein-rich meal greater discomfort and more side effects were reported. Weight and blood pressure decreased at the end of the fasts that followed each of the three meals heart rate increased after the high fat and carbohydrate meals but not after the protein meal. The main laboratory findings were a 40% increase in blood urea nitrogen and higher urine osmolarity after the protein-rich meal than after the other meals.

Conclusion: A protein-poor pre-fast meal is likely to be followed by easier fasting.
 

Background: Carbohydrate malabsorption of lactose, fructose and sorbitol has already been described in normal volunteers and in patients with functional bowel complaints including irritable bowel syndrome. Elimination of the offending sugar(s) should result in clinical improvement.

Objective: To examine the importance of carbohydrate malabsorption in outpatients previously diagnosed as having functional bowel disorders, and to estimate the degree of clinical improvement following dietary restriction of the malabsorbed sugar(s).

Methods: A cohort of 239 patients defined as functional bowel complaints was divided into a group of 94 patients who met the Rome criteria for irritable bowel syndrome and a second group of 145 patients who did not fulfill these criteria and were defined as functional complaints. Lactose (18 g), fructose (25 g) and a mixture of fructose (25 g) plus sorbitol (5 g) solutions were administered at weekly intervals. End-expiratory hydrogen and methane breath samples were collected at 30 minute intervals for 4 hours. Incomplete absorption was defined as an increment in breath hydrogen of at least 20 ppm, or its equivalent in methane of at least 5 ppm. All patients received a diet without the offending sugar(s) for one month.

Results: Only 7% of patients with IBS and 8% of patients with FC absorbed all three sugars normally. The frequency of isolated lactose malabsorption was 16% and 12% respectively. The association of lactose and fructose-sorbitol malabsorption occurred in 61% of both patient groups. The frequency of sugar malabsorption among patients in both groups was 78% for lactose malabsorption (IBS 82%, FC 75%), 44% for fructose malabsorption and 73% for fructose-sorbitol malabsorption (IBS 70%, FC 75%). A marked improvement occurred in 56% of IBS and 60% of FC patients following dietary restriction. The number of symptoms decreased significantly in both groups (P<0.01) and correlated with the improvement index (IBS P<0.05, FC P<0.025).

Conclusions: Combined sugar malabsorption patterns are common in functional bowel disorders and may contribute to symptomatology in most patients. Dietary restriction of the offending sugar(s) should be implemented before the institution of drug therapy.

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IBS = irritable bowel syndrome

FC = functional complaints