Is Helicobacter Pylori Infection a Cause or Treatment Failure of Iron Deficiency Anemia in Children in Bangladesh?
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|ClinicalTrials.gov Identifier: NCT00284700|
Recruitment Status : Completed
First Posted : February 1, 2006
Last Update Posted : February 1, 2006
|First Submitted Date ICMJE||January 31, 2006|
|First Posted Date ICMJE||February 1, 2006|
|Last Update Posted Date||February 1, 2006|
|Study Start Date ICMJE||December 1997|
|Primary Completion Date||Not Provided|
|Current Primary Outcome Measures ICMJE
|Original Primary Outcome Measures ICMJE||Same as current|
|Change History||No Changes Posted|
|Current Secondary Outcome Measures ICMJE
||Prevalence of iron deficiency anemia|
|Original Secondary Outcome Measures ICMJE||Same as current|
|Current Other Pre-specified Outcome Measures||Not Provided|
|Original Other Pre-specified Outcome Measures||Not Provided|
|Brief Title ICMJE||Is Helicobacter Pylori Infection a Cause or Treatment Failure of Iron Deficiency Anemia in Children in Bangladesh?|
|Official Title ICMJE||Is Helicobacter Pylori Infection a Cause or Treatment Failure of Iron Deficiency Anemia in Children in Bangladesh?|
|Brief Summary||Helicobacter pylori is recognized as a major gastrointestinal pathogen in developing countries. This microorganism infects up to 60% of children less than five years in those countries and is strongly associated with chronic gastritis and peptic ulcer disease in children and adults. The progression of gastritis to atrophy often leads to decreased gastric acid output, which is a well-known risk factor for anemia. Gastric acid is essential for increasing the bioavailability and absorption of non-heme dietary iron, the most important source of iron in developing countries. Numerous reports suggest that iron malabsorption secondary to low gastric acid output is a problem in developing world countries. It has been further observed that iron deficiency anemia is resistant to iron therapy particularly in these countries. In a recently completed study we observed an association of anaemia with H. pylori infection. We hypothesize that the poor bioavailability of iron in these countries could be related to H. pylori -induced low gastric acid output and we propose to investigate the role of H. pylori infection as a cause of anemia and treatment failure of iron supplementation in Bangladesh. A prospective, randomized, double-blind, placebo-controlled field trial is proposed among four groups ( 65 each) of H. Pylori infected children of 2-5 years of age with iron deficiency anemia. The children will be assigned to one of the four therapies: antibiotics alone (for H. Pylori eradication), antibiotic plus iron therapy, iron therapy alone, or placebo. Hemoglobin concentration, serum ferritin concentration, and transferrin receptor will be measured before and at 1 and 3 month after the intervention. We also propose a complementary study in an additional 20 children with H. Pylori infection and iron deficiency anemia to assess iron absorption with application of double stable isotopes. The change in hematological parameters will also be compared among the groups before and after the therapy. The results of this study are expected to have implications in the prevention and treatment of iron deficiency anemia in developing countries.|
We propose to complementary study:
2. Iron absorption study Twenty additional children with a positive Urea breath test and iron deficiency anemia will be selected for the Iron absorption study. The purpose of the study and all procedures related to iron absorption study will be explained to the parents and consents will be obtained. Before commencing the iron absorption study, all children will be given a commercial whey adjusted cows’ milk formula with 8 mg Fe/l (Nidina 1; Nestle, Paris, France) for a period of at least three weeks. After 21 days of formula feedings they will be admitted to the Metabolic Ward of Clinical Research and Service Center.
Erythrocyte incorporation of labeled iron (radio stable) has been used successfully to examine absorption from the gut. , The erythrocyte incorporation method involves oral administration of an isotope of iron followed by measurement of the isotope ratio of iron in erythrocytes at a selected time after administration. We will follow the technique for measuring iron absorption in children by a double stable isotope technique, developed recently by Kastenmayer et al.
2.1 Method for Iron absorption study
Preparation of labeled iron sulfate solutions Enriched 57Fe and 58Fe-ferric oxide (Fe2O3) will be purchased from Oak ridge National Laboratory (Oak Ridge, TN, USA). The isotope compositions of iron in the 58Fe preparation (as provided by Oak ridge National Laboratories) are (mg): (weight%) 54 Fe (0.65), 56 Fe (35.6)57 Fe (3.47), and 58 Fe(60.28). The isotope compositions of iron in the 57Fe (weight%) are; 54 Fe(0.65), 56Fe(35.60), 57Fe (3.47), and 58Fe (60.28).
Ferric oxide will be dissolved in concentrated H2SO4 by bubbling carbon monoxide through the solution over heat for approximately four hours. The solution will then be derated by passing purified nitrogen through it for several minutes. The volume will then be adjusted using derated water. Two ml aliquot of the resultants 57 FeSO4 and 58 FeSO4 solutions will be transferred into opaque ampules. Each ampule will be purged with nitrogen and sealed. Ampules will contain either 200 µg/ml of total iron (as ferrous sulphate) and 150 µg/ml of 57Fe or 700 µg/ml of total iron (as ferrous sulphate) and 420 µg/ml of 58Fe. Aliquot from an individual ampule will be used to prepare 57Fe and 58Fe-spiked working solutions.
Stability and safety of parenteral 57 Fe solutions Prior to i.v. administration to the infants the 57FeSO4 solution will be tested for pyrogenicity, sterility, and stability. Limulus amoebocyte lysate (LAL) testing and repeated culture for bacterial and fungal growth to confirm that the 57FeSO4 solutions are pyrogen-free and sterile at the concentrations to be used in the study. The nutrient content of the parenteral solutions has been previously described. The total iron content of the 57FeSO4 -nutrient solution will be determined by atomic absorption spectrometry before and after filtration (0.22 µ filters), and over time at room temperature.
2.2 Study design of iron absorption study Infants enrolled in the study will receive a combination of parenteral and enteral feeds. The 57FeSO4 solution will be provided parenterally while the 58FeSO4 will be given via the enteral route. Erythrocyte incorporation of 57Fe and 58Fe will then be measured from blood samples taken two weeks after initial infusions. The percentage of the I.V administered dose presents in the circulating erythrocytes will be used as a reference for the percentage of absorbed iron (from the orally administered dose) present in the circulating erythrocytes. The “corrected” percent erythrocyte 58Fe and 57Fe incorporation (58 Fe inc-cor/ 57Fe inc-cor) will be calculated mathematically as described below.
Prior to iv administration to the children, 0.7-0.8 ml of the 57FeSO4 solution(0.2mg/ml) will be added to a burytrol containing 30 ml of the nutrient solution used for parenteral feeding, using sterile techniques. The iron-nutrient mixture, which has been used safely previously, will be infused slowly into a peripheral vein of the children over a 12-24 hour period with the aid of an infusion pump.
Soon after the start of the parenteral infusion of the 57FeSO4 solution, the enteral 58FeSO4 will be given to the children. During this time, parenteral infusion of 57FeSO4 will be continued. After checking to ensure that the nasogastric feeding tube is properly located in the stomach, the tube will be aspirated to check stomach contents. If the stomach is empty, 1.5 ml of the 58 FeSO4 will be delivered directly via a syringe into the feeding tube. The tube will then be flushed with 0.5 ml of sterile water. The dosage of parenteral 57FeSO4 will be 0.15mg/kg (57Fe-enriched ferrous sulfate solution), which would provide 0.12 mg/kg of 57Fe. The dosage of enteral will be 1.5mg/kg (58Fe-enriched ferrous sulfate solution), which will provide 0.8mg/kg of 58Fe. The children will be discharged with therapy for Helicobacter pylori infection (Klarithromycin plus omeprazole) for 10 days.
After one month of therapy the mothers will be requested to bring their children at the CRSC. A repeat UBT and iron absorption study will be performed.
2.3 Blood sampling Blood samples will be taken before administration of the stable isotopes (baseline) and 14 days later in both occasions. Blood sample size will be 200-300 µl up per sample.
2.4 Calculation of Erythrocyte Iron Incorporation The quantity administered 58Fe and 57Fe (mg) incorporated into erythrocytes at specified time ‘t’ after administration of the dose of labeled iron will be calculated in a manner similar to that used by Zlotkin et al 1995.
58 Fe inc. =Rt58/54 -Ro58/54 xFe circ x 0.00322 Ro58/54
57Feinc =R157/54-Ro57/54 x Fe circ x 0.0218 Ro57/54
In this equation, 58 Feinc and 57Feinc will be expressed in mg. R158/54, R157/54 and R057/ 54 are the isotope ratios expressed on weight basis for 58Fe/54Fe and 57Fe/54Fe, which will be determined on digested blood samples at time "t" after dosing and at a baseline (pre 58Fe and pre 57Fe doses) respectively; Fe circ is the quantity of the circulating iron. Fe circ at the time “t”; 0.0032 and 0.0218 are the natural abundances (weight fractions) of 58 Fe and 57 Fe. The quantity of total circulating iron, Fe circ, expressed in mg, will be estimated as
Fe circ. =BV x Hb X 3.47
Where BV is the blood volume in liters, assumed to be 0.085l/kg of the body weight; Hb is the hemoglobin concentration in g/l; 3.47 is the concentration of iron in Hb (mg/g).
The quantity of administered 58Fe or 57Fe incorporated into erythrocytes, % Fe inc, will be expressed as a percentage of the administered doses of 58Fe or 57Fe. Feinc.
The corrected percent erythrocyte for analysis of the stable isotope ratios in erythrocytes will be calculated using the percentage of erythrocyte incorporation of i.v infused 57 Fe.
Mass spectrometric analysis Preparation of blood samples for mass spectrometric analysis and preparation of enriched standards will be followed as per the procedures described by Kastenmayer et al. Samples of heparinized whole blood will wet ashed with concentrated HNO3 at a ratio of 1:3 (blood: acid)(vol/vol) on a hot plate over low heat for 20-30 min. Digested solutions will be adjusted with deionized water to yield an iron concentration of 10 µg/ml. Isotope-spiked standards for an instrument calibration will be prepared in the same manner as with the unknown samples. Isotope ratios for 58Fe/54Fe and 57Fe/54Fe in blood before and after concurrent enteral (58Fe) and parenteral (57Fe) administration of isotopes will be determined by a computer-controlled thermal ionization mass spectrometer using an Elan Model 250 ICP/MS system, (SCIEX, Inc., Thornhill, Ontario, Canada), operated in the isotope ratio mode, as followed by Zlotkin et al. in the Department of Pediatric and Nutritional Science, University of Tronoto, Canada.
Intubation test A standard intubation test as described earlier14 will be performed in this subset of children after completion of iron absorption study. In brief, as soft gastric tube (18G) will be placed in most dependent part of stomach. Gastric acid samples will be collected from children lying in the left recumbent position using manual suction. The position of the tube will be confirmed by auscultation, aspiration of gastric juice, and nearly complete recovery of water injected in the tube. Samples of gastric juice will be discarded during the first 10 min after intubation. Thereafter, samples will be collected and saved in 15- min aliquot for 90 min. After 90 min of collection (basal sample), pentagastrin (peptavlon, ICI) will be injected subcutaneously at a dose of 0.6 ug/kg. The sample following pentagastrin stimulation for 60 min will be termed as "stimulated sample". The volime of gastric secretion in each of the 15 min collections will be rcorded and expressed as mililitre per hour. The concentrations of acid in each will be measured by titration of 1 mL gastric juice with 0.01N sodium hydroxide to pH 7.4, using an automated titrator (Metrohm, Herisau, Switzerland). Total acid output was calculated for each time pint by multiplying volume of gastric juice and acid concentration. Basal (BAO) and stimulated acid output (SAO) were calculated based on 2 samples collected for baseline measurement and the 4 samples collected after administration of pentagastrin respectively, and were expressed as mMol/h.
|Study Type ICMJE||Interventional|
|Study Phase ICMJE||Not Applicable|
|Study Design ICMJE||Allocation: Randomized
Intervention Model: Parallel Assignment
Primary Purpose: Treatment
|Intervention ICMJE||Drug: Iron|
|Study Arms ICMJE||Not Provided|
|Publications *||Not Provided|
* Includes publications given by the data provider as well as publications identified by ClinicalTrials.gov Identifier (NCT Number) in Medline.
|Recruitment Status ICMJE||Completed|
|Original Enrollment ICMJE||Same as current|
|Study Completion Date ICMJE||May 2001|
|Primary Completion Date||Not Provided|
|Eligibility Criteria ICMJE||
|Ages ICMJE||2 Years to 5 Years (Child)|
|Accepts Healthy Volunteers ICMJE||Not Provided|
|Contacts ICMJE||Contact information is only displayed when the study is recruiting subjects|
|Listed Location Countries ICMJE||Bangladesh|
|Removed Location Countries|
|NCT Number ICMJE||NCT00284700|
|Other Study ID Numbers ICMJE||ICDDRB 97-004|
|Has Data Monitoring Committee||Not Provided|
|U.S. FDA-regulated Product||Not Provided|
|IPD Sharing Statement ICMJE||Not Provided|
|Responsible Party||Not Provided|
|Study Sponsor ICMJE||International Centre for Diarrhoeal Disease Research, Bangladesh|
|Collaborators ICMJE||Not Provided|
|PRS Account||International Centre for Diarrhoeal Disease Research, Bangladesh|
|Verification Date||January 2006|
ICMJE Data element required by the International Committee of Medical Journal Editors and the World Health Organization ICTRP