Helicobacter pylori gastritis and sideropenic refractory anemia

The role of hepcidin, ferroportin, HCP1, and DMT1 protein in iron absorption in the human digestive tract

Iron is found in almost all foods, so dietary iron intake is related to energy intake. However, its availability for absorption is quite variable, and poor bioavailability is a major reason for the high prevalence of nutritional iron deficiency anaemia. Absorption occurs primarily in the proximal small intestine through mature enterocytes located at the tips of the duodenal villi. Two transporters: Hem Carrier Protein 1 (HCP1) and Divalent Metal Transporter 1 (DMT1) appear to mediate the entry of most if not all dietary iron into these mucosal cells. Absorption is regulated according to the body's needs. The results of studies suggest that iron absorption is regulated by the control of iron export from duodenal enterocytes to the circulating transferrin pool by ferroportin. Hepcidin, a 25-amino acid polypeptide, which is synthesised primarily in hepatocytes, reduces the iron absorption from the intestine by binding to the only known cellular iron exporter, ferroportin, causing it to be degraded. Therefore, hepcidin is now considered to be the most important factor controlling iron absorption.

Helicobacter pylori infection and extragastric disorders in children: a critical update

Helicobacter pylori (H. pylori) is a highly prevalent, serious and chronic infection that has been associated causally with a diverse spectrum of extragastric disorders including iron deficiency anemia, chronic idiopathic thrombocytopenic purpura, growth retardation, and diabetes mellitus. The inverse relation of H. pylori prevalence and the increase in allergies, as reported from epidemiological studies, has stimulated research for elucidating potential underlying pathophysiological mechanisms. Although H. pylori is most frequently acquired during childhood in both developed and developing countries, clinicians are less familiar with the pediatric literature in the field. A better understanding of the H. pylori disease spectrum in childhood should lead to clearer recommendations about testing for and treating H. pylori infection in children who are more likely to develop clinical sequelae. A further clinical challenge is whether the progressive decrease of H. pylori in the last decades, abetted by modern clinical practices, may have other health consequences.

Unintended consequences of Helicobacter pylori infection in children in developing countries: iron deficiency, diarrhea, and growth retardation

Helicobacter pylori infection is predominantly acquired early in life. The prevalence of the infection in childhood is low in developed countries, whereas in developing countries most children are infected by 10 y of age. In poor resource settings, where malnutrition, parasitic/enteropathogen and H. pylori infection co-exist in young children, H. pylori might have potentially more diverse clinical outcomes. This paper reviews the impact of childhood H. pylori infection in developing countries that should now be the urgent focus of future research. The extra-gastric manifestations in early H. pylori infection in infants in poor resource settings might be a consequence of the infection associated initial hypochlorhydria. The potential role of H. pylori infection on iron deficiency, growth impairment, diarrheal disease, malabsorption and cognitive function is discussed in this review.

Association between Helicobacter pylori infection detected by the (13) C-urea breath test and low serum ferritin levels among Japanese adults

BACKGROUND

Helicobacter pylori infection is a major risk factor for chronic gastritis, digestive ulcers, and gastric cancer. Previous studies have shown associations between H. pylori infection and decreased iron storage. Therefore, this study aimed to examine the associations between H. pylori infection and serum iron and ferritin levels in Japan.

MATERIALS AND METHODS

Overall, 268 Japanese individuals who visited a clinic located in an urban area for H. pylori infection tests and subsequent eradication were enrolled. H. pylori infection was diagnosed by a (13) C-urea breath test, with positive results defined as values ≥2.5‰.

RESULTS

The overall infection rate was 65.3% (175/268). The geometric mean serum iron levels in uninfected and infected subjects were 115.7 μg/dL and 108.9 μg/dL, respectively, in men, and 83.9 and 91.8 μg/dL, respectively, in women. The geometric mean serum ferritin levels were 128.9 and 81.0 ng/mL, respectively, in men, and 25.5 and 27.0 ng/mL, respectively, in women. Regression analysis adjusted for age showed that lower geometric mean serum ferritin levels were significantly associated with H. pylori infection in men (131.8 vs 79.4 ng/mL p = .009) and in women (33.9 vs 23.4 ng/mL p = .041). The difference was greater in subjects ≥50 years old, although the interaction was not statistically significant. Helicobacter pylori infection was not significantly associated with serum iron levels.

CONCLUSION

This study showed that H. pylori infection was significantly associated with altered serum ferritin levels in Japanese individuals, particularly in those aged ≥50 years.

Lactoferrin levels in the gastric tissue of Helicobacter pylori-positive and -negative patients and its effect on anemia

Aim. To determine gastric tissue lactoferrin (Lf) levels of Helicobacter pylori- (Hp-) positive and -negative patients and its effect on anemia. Methods. Cases in which initial presentation was of abdominal pain and that were Hp-positive at endoscopy were included. Hp-positive cases and -negative controls were divided into two groups. Results. The study included 64 cases (average: 10.2 ± 0.4 years, 39 male and 25 female). Lf levels were subsequently studied on 61 cases. 45 (73.8%) of these were Hp-positive, while 16 (22.2%) were Hp-negative. In Hp-positive cases, mean staining percentages and density of glands in the antral mucosa were 45.5 ± 4.7% and 1.9 ± 0.1, respectively. Hp-negative cases showed significantly different values of 17.8 ± 4.5% and 1.3 ± 0.2, respectively. Hemoglobin and serum ferritin values of Hp-positive cases were 12.7 ± 0.2 g/dL and 32.5 ± 2 ng/mL, but these were comparable with Hp-negative cases (12.6 ± 0.1 g/dL and 30.7 ± 4.4 ng/mL). Conclusions. Tissue Lf was significantly higher in Hp-positive cases compared to Hp-negative cases, but no difference was observed between the two groups with regards to hemoglobin and ferritin level. As a result, it is difficult to say that this rise in Lf plays a role in the development of iron deficiency anemia in Hp-positive patients.

Consequences of Helicobacter pylori infection in children

Although evidence is emerging that the prevalence of Helicobacter pylori (H. pylori) is declining in all age groups, the understanding of its disease spectrum continues to evolve. If untreated, H. pylori infection is lifelong. Although H. pylori typically colonizes the human stomach for many decades without adverse consequences, children infected with H. pylori can manifest gastrointestinal diseases. Controversy persists regarding testing (and treating) for H. pylori infection in children with recurrent abdominal pain, chronic idiopathic thrombocytopenia, and poor growth. There is evidence of the role of H. pylori in childhood iron deficiency anemia, but the results are not conclusive. The possibility of an inverse relationship between H. pylori and gastroesophageal reflux disease, as well as childhood asthma, remains a controversial question. A better understanding of the H. pylori disease spectrum in childhood should lead to clearer recommendations about testing for and treating H. pylori infection in children who are more likely to develop clinical sequelae.

Low prevalence of iron-deficiency anaemia among Inuit preschool children: Nunavut Inuit Child Health Survey, 2007–2008

Objective

To report the prevalence rates and correlates for anaemia, iron deficiency (ID) and iron-deficiency anaemia (IDA) among Inuit preschool-aged children.

Design

A cross-sectional study assessed iron intake, demographic information, medical history, anthropometrics, Hb, ferritin, C-reactive protein and antibodies toHelicobacter pylori.

Setting

Sixteen selected Inuit communities in Nunavut Territory, Canada.

Subjects

Inuit (n388) aged 3–5 years randomly recruited from communities.

Results

Anaemia (3–4 years: Hb < 110 g/l; 5 years: Hb < 115 g/l) was prevalent in 16·8 % of children. The prevalence of ID (ferritin < 12 μg/l) was 18·0 % and that of IDA was 5·4 %. When ID was defined as ferritin <10 μg/l, 10·8 % of children were iron deficient and 3·3 % had IDA. In multiple logistic regression, boys were more likely to be iron deficient (OR = 2·28, 95 % CI 1·17, 8·25), but no other risk factor emerged for ID. Three- to 4-year-olds were less likely than 5-year-olds to have anaemia from causes other than ID (OR = 0·11, 95 % CI 0·08, 0·58). Anaemia from other causes was more common among children residing in crowded homes (OR = 2·30, 95 % CI 1·37, 12·31) and those treated for past-year ear infection (OR = 1·35, 95 % CI 1·05, 7·21).

Conclusions

The low prevalence of ID and IDA is encouraging, but efforts are still needed to reduce rates as they continue to be higher than general population rates. Household crowding and infections may contribute to anaemia and warrant further research.

Helicobacter pylori infection does not influence the efficacy of iron and vitamin B(12) fortification in marginally nourished Indian children

BACKGROUND/OBJECTIVES

Helicobacter pylori infection and iron and vitamin B(12) deficiencies are widespread in economically disadvantaged populations. There is emerging evidence that H. pylori infection has a negative effect on the absorption of these micronutrients. The aim of this study was to evaluate the effect of H. pylori infection on the efficacy of micronutrient (including iron and vitamin B(12))-fortified foods supplied for 1 year in marginally nourished children.

SUBJECTS/METHODS

In all, 543 Indian children, aged 6-10 years, participated in a double-blind, randomized controlled intervention trial, receiving foods fortified with either high (100% Recommended Dietary Allowances (RDA)) or low (15% RDA) amounts of iron, vitamin B(12) and other micronutrients. The presence of H. pylori infection was diagnosed by the (13)C-labeled urea breath test at 11 months after the start of the intervention. Blood hemoglobin, serum ferritin (SF), total body iron and plasma vitamin B(12) were estimated at baseline and 12 months, and differences between these time points were assessed using an independent t-test.

RESULTS

Overall, the prevalence of H. pylori infection in this group of children was 79%. Baseline hemoglobin, SF, body iron and vitamin B(12) concentrations were not associated with H. pylori infection. The response to the intervention (either high or low amounts of iron and vitamin B(12) fortification) in terms of change in iron markers and vitamin B(12) status did not differ between children with and without H. pylori infection.

CONCLUSIONS

This study shows that the presence of H. pylori infection did not affect the efficacy of long-term iron and vitamin B(12) fortification in these marginally nourished children.

Iron deficiency anemia in Helicobacter pylori infection: meta-analysis of randomized controlled trials

BACKGROUND

Helicobacter pylori (H. pylori) infection and iron deficiency anemia are prevalent in disadvantaged populations worldwide. The benefit of H. pylori eradiation for iron deficiency anemia has been extensively studied, but data are still equivocal.

METHODS

A search in The Cochrane Library, PUBMED, EMBASE, EBM Review databases, Science Citation Index Expanded, and CMB (Chinese Biomedical Literature Database) was performed. Randomized controlled trials (RCTs) comparing anti-H. pylori plus oral iron to oral iron alone for the iron deficiency patients in whom H. pylori was positive were selected for meta-analysis. Reviev Manager 5.0 software was used for the performance of meta-analysis.

RESULTS

Sixteen randomized controlled trials totaling 956 patients were included. The meta-analysis showed that the difference from baseline to endpoint of hemoglobin (Hb), serum iron (SI), and serum ferritin (SF) was statistically significantly different between anti-H. pylori treatment plus oral iron and oral iron alone (SMD, Hb 1.48; 95% CI, 0.96, 2.00; p < 0.00001; SI 1.15; 95% CI, 0.87, 1.43; p < 0.00001; SF 1.84; 95% CI, 1.20, 2.48; p < 0.00001, respectively).

CONCLUSIONS

Our study suggests that treatment of H. pylori infection could be effective in improving anemia and iron statue in IDA patients infected by H. pylori, particularly in patients with moderate or severe anemia.

A short review of malabsorption and anemia

Anemia is a frequent finding in most diseases which cause malabsorption. The most frequent etiology is the combination of iron and vitamin B12 deficiency. Celiac disease is frequently diagnosed in patients referred for evaluation of iron deficiency anemia (IDA), being reported in 1.8%-14.6% of patients. Therefore, duodenal biopsies should be taken during endoscopy if no obvious cause of iron deficiency (ID) can be found. Cobalamin deficiency occurs frequently among elderly patients, but it is often unrecognized because the clinical manifestations are subtle; it is caused primarily by food-cobalamin malabsorption and pernicious anemia. The classic treatment of cobalamin deficiency has been parenteral administration of the vitamin. Recent data suggest that alternative routes of cobalamin administration (oral and nasal) may be useful in some cases. Anemia is a frequent complication of gastrectomy, and has been often described after bariatric surgery. It has been shown that banding procedures which maintain digestive continuity with the antrum and duodenum are associated with low rates of ID. Helicobacter pylori (H pylori) infection may be considered as a risk factor for IDA, mainly in groups with high demands for iron, such as some children and adolescents. Further controlled trials are needed before making solid recommendations about H pylori eradication in these cases.

Controlled, household-randomized, open-label trial of the effect of treatment of Helicobacter pylori infection on iron deficiency among children in rural Alaska: results at 40 months

BACKGROUND

Helicobacter pylori infection treatment was found not to reduce the prevalence of iron deficiency or anemia among Alaska Native children at 14 months after treatment initiation. We hypothesized that 14 months was to early to resolve H. pylori-induced gastric damage. Consequently, we conducted a 40-month follow-up.

METHODS

We enrolled 219 children 7-11 years old who had H. pylori infection (as diagnosed by (13)C-labeled urea breath test) and iron deficiency (serum ferritin level, <22.47 pmol/L) in a controlled, household-randomized trial of the effect of treatment of H. pylori on iron deficiency and anemia (hemoglobin level, <115 g/L). At 40 months, 176 children were evaluated.

RESULTS

Forty-four (52%) of 85 children in the intervention group and 53 (58%) of 91 in the control group had iron deficiency (adjusted relative risk [ARR], 0.92 [95% confidence interval {CI}, 0.68-1.26]), versus 4 (5%) and 17(19%), respectively, with both iron deficiency and anemia (ARR, 0.25 [95% CI, 0.09-0.73]). Reinfection occurred among 33 (52%) of 64 children who had cleared their infection. H. pylori-negative children had lower prevalences of iron deficiency (ARR, 0.62 [95% CI, 0.38-1.01]) and iron deficiency and anemia (ARR, 0.22 [95% CI, 0.03-1.50]), compared with H. pylori -positive children.

CONCLUSIONS

The resolution of H. pylori infection for >14 months modestly reduced the prevalence of iron deficiency and substantially reduced the prevalence of iron deficiency and anemia. H. pylori likely plays a casual role in hematological outcomes for some children.

Helicobacter pylori infection and iron stores: a systematic review and meta-analysis

BACKGROUND AND AIMS

We carried out a systematic literature review and meta-analysis to evaluate the existing evidence on the association between Helicobacter pylori infection and iron stores.

METHODS

Twelve case reports and case series, 19 observational epidemiologic studies and six intervention trials were included in the review.

RESULTS

Although only few studies controlled for multiple potential confounders, most studies reported a positive association, linking between H. pylori and decreased body iron stores in symptomatic and asymptomatic H. pylori-infected subjects. H. pylori infection may be regarded as a risk factor for reduction in body iron stores and also for iron deficiency or iron deficiency anemia, especially in high-risk groups. The results of the meta-analysis of thoroughly designed and analyzed studies revealed an increased risk for iron deficiency anemia; pooled odds ratio (OR) 2.8 (95% confidence interval (CI) 1.9, 4.2) and also for iron deficiency; pooled OR 1.38 (95%CI 1.16-1.65) among H. pylori-infected subjects. The biologic mechanism by which H. pylori induces the alteration in the iron stores is not fully understood, but it seems to involve several pathways, including gastrointestinal blood loss, decrease in the absorption of dietary iron, and enhanced uptake of the iron by the bacterium.

CONCLUSIONS

H. pylori is associated with reduced iron stores. Future research is needed to determine whether this relationship is a causal association and to better understand its biologic mechanism. The impact of anti-H. pylori therapy on improvement of iron stores needs to be further evaluated in large and well-controlled trials.

Helicobacter pylori, anemia, and iron deficiency: relationships explored among Alaska native children

BACKGROUND

Attempts to understand determinants of anemia and iron deficiency have led researchers to examine the role of Helicobacter pylori infection. The current study assessed determinants of anemia and iron deficiency, including H. pylori, in Alaska Native children.

METHODS

In 1999, a population-based survey was conducted among 86 children (67% response rate), mean age of 43.7 months (standard deviation = 16.8 months). Samples of breath, stool, and venous blood were obtained from children for measures of anemia, iron deficiency, H. pylori, fecal blood loss, and current inflammation. Standardized interviews with parents provided information on demographics, illness, and intake of dietary iron, iron-absorption inhibitors, and enhancers.

RESULTS

Of the 86 children studied, 17.4% were anemic and 38.6% were iron deficient. Forty-one percent of the cohort had H. pylori-specific IgG antibodies, 86% tested positive by the urea breath test (UBT), and 80% tested positive by the stool antigen test. Presence of H. pylori antibodies emerged as a significant risk factor for anemia and iron deficiency in adjusted analyses controlling for demographic factors, current inflammation, and antibiotic use. In contrast, children with positive UBT or stool antigen results were significantly less likely to have anemia or iron deficiency than those with negative results.

CONCLUSIONS

Results from different measures of H. pylori may reflect different stages of infection. Relationships between H. pylori and anemia/iron deficiency may depend on the phase of infection measured, with serologic tests reflecting established H. pylori infection associated with anemia/iron deficiency, and UBT and stool antigen results reflecting an earlier stage of infection.

The stomach and iron deficiency anaemia: a forgotten link

Iron deficiency anaemia is generally considered a sign of occult bleeding from the gastrointestinal tract, and standard care therefore includes evaluation of the gastrointestinal tract to rule out possible bleeding sites. However, it is often overlooked that iron deficiency anaemia may be the result of an imbalance between iron loss and iron intake, and may also be due to reduced absorption of iron from food, i.e., coeliac disease. The absorption of alimentary iron is not a simple process and the stomach plays a major role in this process of iron "digestion". This review presents evidence linking iron deficiency anaemia to gastric conditions that lead to reduced acid secretion, such as, for example, gastric surgery, atrophic body gastritis and Helicobacter pylori gastritis.

An association between Helicobacter pylori infection and serum vitamin B12 levels in healthy adults

GOALS

To determine whether serum vitamin B12 levels in non-vitamin B12 deficient healthy adults correlate with serological evidence of H. pylori infection.

BACKGROUND

An association between H. pylori infection and vitamin B12 deficiency has been recently reported.

STUDY

133 adults, presenting to a community based primary care clinic who met the following exclusion criteria; history of H. pylori eradication or antacid use, liver disease, inflammatory bowel disease, previous gastrointestinal surgery, a vegetarian diet or multivitamin supplementation were studied. Blood was drawn for a complete blood count, serum vitamin B12, gastrin, folic acid and H. pylori IgG antibodies. Subjects with vitamin B12 < or = 145 ng/mL (deficient range) were excluded.

RESULTS

Of 133 subjects 96 (72.2%) were seropositive for H. pylori IgG antibodies (HP+). Age of HP(+) subjects did not differ from that of seronegative subjects (HP-); 52.8 +/- 1.6 mean +/- SE versus 49.2 +/- 2.9 ( = NS). Prevalence of HP seropositivity was significantly higher among subjects with borderline (>145-180 pg/mL) or low normal (>180-250 pg/mL) vitamin B12 levels than among those with vitamin B12 > 250 pg/mL; among 25 subjects with vitamin B12 > 145-180 pg/mL 92% were seropositive and among 47 subjects with vitamin B12 > 180-250 pg/mL 89% were seropositive as compared with 31/61 (51%) of subjects with B12 > 250 pg/mL, Fisher exact test < 0.0001. Vitamin B12 levels did not correlate with age (r = -0.07). Gastrin levels (pg/mL) did not differ significantly between groups; 70.2 +/- 5.8 in HP(+) versus 56.0 +/- 12.4 in HP(-).

CONCLUSIONS

The higher prevalence of H. pylori infection among subjects with serum vitamin B12 levels that are within the lower end of the normal range suggests a causal relationship between H pylori infection and vitamin B12 levels in healthy adults.

Gastric mucosa: long-term outcome after cure of Helicobacter pylori infection

The histopathological changes due to chronic Helicobacter pylori infection are well characterized. Nevertheless, the clinical and pathological outcomes resulting from the cure of this infection remain incompletely described. In particular, the influence of eradication of H. pylori on nonulcer dyspepsia, the long-term effects of H. pylori eradication on gastric atrophy and intestinal metaplasia, and the role of H. pylori eradication in the prevention of gastric cancer are still unclear. We reviewed 38 studies reported between 1993 and 1999 on the outcome of various disorders related to H. pylori infection after successful eradication. There is general agreement concerning the regression of chronic gastritis, lymphoid follicles, and limited-stage low-grade MALT lymphomas of the gastric mucosa after eradication of H. pylori infection. Conversely, there are still major questions on whether H. pylori eradication improves the outcome of premalignant lesions, such as atrophy, intestinal metaplasia, and dysplasia. Finally, some extragastric idiopathic diseases seem to improve in consequence of the eradication of the infection, although there are still no definitive data to support this.

Helicobacter pylori-related iron deficiency anemia: a review

Several clinical reports have demonstrated that Helicobacter pylori gastric infection has emerged as a new cause of refractory iron deficiency anemia, unresponsive to iron therapy, and not attributable to usual causes such as intestinal losses or poor intake, malabsorption or diversion of iron in the reticulo-endothelial system. Although the interaction between infection and iron metabolism is now well consolidated, our understanding of the pathogenetic mechanism underlying the anemia is still wanting. Microbiological and ferrokinetic studies seem to suggest that Helicobacter pylori infected antrum could act as a sequestering focus for serum iron by means of outer membrane receptors of the bacterium, that in vitro are able to capture and utilize for growth iron from human lactoferrin. The proposed hypothesis does not answer why this complication is such a rare disease outcome in a common human infection but it may be used as a template for further controlled studies to determine the mechanisms of this atypical, medically important putative sequelae of H. pylori infection.

Iron-deficiency anemia associated with Helicobacter pylori gastritis

BACKGROUND

Recent studies have suggested an association of Helicobacter pylori and iron-deficiency anemia (IDA). This is a report of six cases of IDA associated with H. pylori gastritis.

METHODS

Six patients with IDA were studied (5 boys and 1 girl; mean age 13.6 years; range 13-15 years). Five had a medical history of long-standing IDA and of oral iron supplementation at outpatient clinics. The anemia recurred after the iron therapy had been discontinued. The sixth patient was admitted to the hospital with severe IDA. An extensive work-up was ordered that included technetium-99m (99mTc) scans for Meckel's diverticulum, total colonoscopy, and gastrointestinal endoscopy. After biopsy-based H. pylori test results were confirmed to be positive, anti-H. pylori therapy consisting of lansoprazole, clarithromycin, and metronidazole was administered for 2 weeks with no iron supplementation. The hematologic profile and iron status were assessed periodically after the end of the eradication regimen.

RESULTS

Upper gastrointestinal endoscopy revealed a marked antral nodularity but no evidence of bleeding lesions in all the patients. Given the histology and the fact that rapid urease test results were positive, chronic active gastritis with H. pylori was diagnosed in all these cases. H. pylori was successfully eradicated in all the patients. There was no evidence of IDA in any of the follow-up examinations between 27 and 50 months after anti-H. pylori therapy.

CONCLUSIONS

H. pylori infection may be involved in cases of IDA of unknown origin, and the eradication of H. pylori can be associated with the resolution of anemia.

Reversal of iron deficiency anemia after Helicobacter pylori eradication in patients with asymptomatic gastritis

BACKGROUND

Iron deficiency anemia is the most common form of anemia worldwide. Recent studies have suggested an association between Helicobacter pylori infection and iron deficiency.

OBJECTIVE

To investigate the effects of eradicating H. pylori with combination antibiotic therapy on iron deficiency anemia in patients with H. pylori-associated gastritis.

DESIGN

Case series.

SETTING

University hospital.

PATIENTS

30 patients with a long history of iron deficiency anemia in whom H. pylori-associated gastritis was the only pathologic gastrointestinal finding detected.

INTERVENTION

Eradication therapy with two antibiotics and discontinuation of iron replacement therapy.

MEASUREMENTS

Complete blood count, ferritin levels, and gastroscopy with biopsy to evaluate H. pylori status.

RESULTS

At 6 months, 75% of patients had recovered from anemia (P<0.001), ferritin values increased from 5.7+/-0.7 microg/L to 24.5+/-5.2 microg/L (95% CI, 8.85 to 29.97). After 12 months, 91.7% of patients had recovered from anemia.

CONCLUSIONS

Cure of H. pylori infection is associated with reversal of iron dependence and recovery from iron deficiency anemia.

Serum ferritin, hemoglobin, and Helicobacter pylori infection: a seroepidemiologic survey comprising 2794 Danish adults

BACKGROUND & AIMS

Helicobacter pylori infection was recently associated with iron-deficiency anemia. The aim of this study was to examine the relationship between H. pylori infection, hemoglobin, and iron status using serum ferritin as a marker for total body iron.

METHODS

Serum ferritin, hemoglobin, and immunoglobulin G (IgG) antibodies against H. pylori were assessed in 2794 Danish adults who attended a population survey. IgG antibodies were measured with an in-house enzyme-linked immunosorbent assay, serum ferritin with an immunoradiometric assay, and hemoglobin with Coulter-S.

RESULTS

The seroprevalence of H. pylori infection did not relate to hemoglobin. Serum ferritin levels were significantly lower in men (114 vs. 120 microg/L; P = 0.01) and in postmenopausal women (63 vs. 77 microg/L; P = 0.02) who were IgG positive than in seronegative individuals. IgG-positive people more often had reduced serum ferritin levels (</=30 microg/L) than seronegative people. This association persisted in multivariate analysis after adjusting for possible confounding factors (odds ratio, 1.4; 95% confidence interval 1.1-1. 8).

CONCLUSIONS

Serum ferritin levels are reduced in people with increased IgG antibodies to H. pylori. H. pylori infection affects iron metabolism in humans.