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 helicobacter pylori ( hp ) is an important etiologic cause of diseases such as chronic gastritis , duodenal and gastric ulcers , atrophic gastritis , intestinal metaplasia , and gastric lymphoma ( mucosa - associated lymphoid tissue , malt lymphoma type ) [ 1 , 2 ] .
many studies suggest a relationship between iron deficiency anemia ( ida ) and hp infection , but it is not clear the mechanism by which this occurs [ 3 , 4 ] .
one of the suggested mechanisms occurs through hp - mediated lf increase in gastric tissue via neutrophils .
the iron , thus , bound to lf is in turn picked up by the bacterium , by means of its outer membrane receptors , for its own growth . as h. pylori turnover is very rapid ,
the bacterial iron stores are rapidly lost in the stools , together with the dead bacteria .
this mechanism , or at least its template , could explain why an iron supply is no longer available for hemopoiesis , which only enhances h. pylori proliferation [ 5 , 6 ] .
the proposed hypothesis is not able to answer why ida does not develop in all infected subjects .
it is possible that the presence of specific bacterium strains and the high needs for iron required by the host under particular conditions could both play a crucial role in the onset of ida . therefore , the purpose of this study is to determine the lf levels in the gastric tissue of hp - positive and -negative patients and whether this has an effect on anemia
patients over 4 years of age with recurring abdominal pain of unknown cause who subsequently underwent endoscopy at our hospital 's pediatric gastroenterology , hepatology and nutrition department have been included in the study .
before the patients were examined , their families were informed within the frame of the helsinki report , and their signatures were taken on an informed consent form . following record of age , gender , weight , height , and clinical details ,
, biopsy samples were taken from the gastric antrum for histological examination and tissue lf measurement .
blood was taken from all cases for full blood count , serum iron , iron binding capacity ( ibc ) , total iron binding capacity ( tibc ) , and ferritin level .
patients with a digestive system or systemic disorder other than hp gastritis , cases previously treated for hp gastritis or peptic ulcer disease , and patients taking proton pump inhibitors or antibiotics were not included in the study . tissue lf level was evaluated by a blinded pathology specialist , who was not informed about the patients ' clinical progress or the gastric antral immunohistochemical study results from primary antibody assays ( dakocytomation , lsab2 system - hrp , denmark ) .
lactoferrin was quantitated immunohistochemically by two methods : in the first method , all samples were evaluated from 0% to 100% according to the staining percentage of glands in the antrum ; in the second method , all samples were evaluated based on no staining ( 0 ) , light ( 1 ) , medium ( 2 ) , or dense ( 3 ) according to stain - holding densities of glands in the antrum .
biopsy samples of cases were also grouped as no neutrophils ( 0 ) , light ( 1 ) , medium ( 2 ) , or dense ( 3 ) according to the density of lf - secreting neutrophils . data from this study were analyzed using the spss statistics software package .
nonparametric mannwhitney u and chi - square tests were used to compare the data . in all tests ,
the study consisted of 64 patients with ages ranging between 4 and 17 years ( average : 10.2  0.4 years ) .
39 ( 60.9% ) of the cases were male , while 25 ( 39.1% ) were female . as a result of histological examination of the gastric antrum biopsy samples , 48 ( 75% ) out of 64 cases
were found to be hp - positive , while 16 ( 25% ) cases were hp - negative .
antral nodularity in hp - positive group was significantly higher compared to hp - negative group ( p = 0.008 ) , ( 95% confidence interval ( ci ) = 0.0060.01 ) .  
the average age of positive cases was 10.9  0.5 years , and the average age of negative cases was 8.1  0.9 , which was statistically significant ( p = 0.009 ) .
positive hp was seen in more male patients , but this difference was statistically insignificant ( p = 0.1 ) .
; ibc , tibc , ferritin levels ; full blood count and hemoglobin ( hb ) , hematocrit ( htc ) , leucocyte ( wbc ) , thrombocyte ( plt ) , and erythrocyte count ( rbc ) ; average erythrocyte volume ( mcv ) , average erythrocyte hemoglobin concentration ( mchc ) , erythrocyte distribution range ( rdw ) , and average erythrocyte hemoglobin ( mch ) values were also separately evaluated for hp - positive and -negative cases , but no significant differences were observed .
results of power analyses for mann - whitney tests provided a wide range from very low to very high such as 0.051 for hb , 0.386 for htc , 0.421 for ferritin , and 0.948 for serum iron .
these results can be interpreted as % 39 power to detect a difference between htc values of two groups with sample sizes of 16 and 48 .
three cases had insufficient tissue for assay , tissue lf was only measured in the remaining 61 cases .
45 of these cases were hp - positive , while 16 were hp - negative . in hp
positive cases , staining percentages and density of glands in the antral mucosa were 45.5  4.7% and 1.9  0.1 , respectively , while these figures were 17.8  4.5% and 1.3  0.2 [ ( p = 0.001 , ci = 0.00.048 ) , ( p = 0.016 , ci = 0.00.048 ) ] in hp - negative cases .
the neutrophil density in the hp - positive group was also significantly higher compared to the hp - negative group .
one of the most important clinical findings caused by hp infection other than gastrointestinal diseases is anemia
. there are quite a number of studies in the literature demonstrating the relationship between hp and anemia in both adults and infants [ 912 ] .
for example , in a study of young patients in south korea , ida in individuals infected with hp was reported as 2.9 times higher compared to uninfected cases .
it has been reported that this anemia did not improve despite iron treatment , but the hemoglobin , serum iron , and ferritin levels improved following treatment of hp infection . in a random , placebo - controlled study in 43 infants and adults , hemoglobin levels were also reported to be significantly improved following hp treatment .
in addition to studies suggesting a relationship between hp and anemia , there are also studies suggesting the opposite .
in a study conducted on 1060 cases , reported that there was no significant difference between serum ferritin level and hp in both males and females . in a review of the current data ,
bini   tried to analyze whether hp was really to blame for anemia in these cases or whether it is an innocent bystander .
he tried to find the answers as to why hp causes anemia in only a small percentage of infected patients , how this organism causes anemia if at all , and whether or not there is improvement in anemia after treatment .
as a result of this evaluation , it was shown that hp positively correlated with low levels of ferritin , though this may not play a direct role .
our results were contrary to other studies that reported a relationship between hp and ida , as there was no significant difference between the average hemoglobin , hematocrit , serum iron , and ferritin levels of hp - positive and hp - negative groups ( table 3 ) .
despite all these results , it is still unclear with which mechanism hp causes ida in these cases .
mechanisms proposed include loss of blood from the digestive system , poor iron intake , iron absorption disorder , and use of iron in the reticuloendothelial system [ 11 , 18 , 19 ] , and hp is an etiological factor for gastric atrophy . hypo- or achlorhydria may develop in individuals with atrophic gastritis , and iron absorption may decrease as a result .
contrary to current theory , it has been proposed that lf secreted from hp - activated neutrophils in the stomach transfers iron to the outer cell wall receptor of hp and that an ida then results [ 6 , 7 ] .
though not many studies support this theory , nakao et al .   reported that there is a significant increase in lf in the gastric fluids and mucosal tissue samples in hp - infected patients .
lonnerdal and iyer   reported that the main cause of this lf increase in gastric tissue was the increase in the inflammatory mediator interleukin-8 causing attraction of neutrophils and monocytes which then secrete lf . a different study by nakao et al
.   also reported a marked relationship between interleukin levels in the gastric mucosa and lf increase .
reported a study on 101 patients with unexplained epigastric pain and/or iron deficiency , which found markedly high lf levels in the hp - positive and anemia group , and lf levels in the hp - positive group were found to be significantly raised relative to the control group and anemia - only group . in the same study , control endoscopy 8 weeks after hp treatment of 12 of the hp - positive cases with anemia measured lf and hemoglobin levels in the gastric tissue biopsies .
they reported a decrease in tissue lf and a marked increase in hemoglobin compared to pretreatment . in this study , staining percentage of antral gland cells of hp - positive cases and staining density of cells were significantly higher compared to hp - negative cases ( p = 0.001 , p = 0.016 ) .
moreover , the percentage of stained neutrophils in hp - positive cases was markedly higher compared to hp - negative cases ( p = 0.001 ) .
the increase in lf in hp - positive cases agreed with previously conducted studies , but conversely , hemoglobin , hematocrit , and ferritin levels in these cases did not differ ( table 3 ) .
these results did not match the hypothesis that anemia is caused by loss of iron to hp bacteria via lf in the gastric tissue of hp - positive cases .
we can conclude that the increase of lf in the gastric tissue of hp - positive cases is dependent upon inflammation .
however , this iron does not seem to be transferred to hp , as overall iron levels did not decrease in these patients and so we can not say that the increase in lf is connected with the subsequent development of 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 .