[Intensification of Helicobacter pylori colonization and serological markers of Helicobacter pylori infection and cytotoxicity in blood]

Colonization of H. pylori bacteria on the surface of gastric epithelium is the first stage of infection in alimentary tract. Despite the local cell-mediated reaction, in the majority of patients there does not come to the elimination of bacteria: there develops an acute and then chronic inflammatory process. B lymphocytes begin the production of all classes of specific antibodies against H. pylori proteins presented to them. The number of anti-H. pylori antibodies increases both in gastric mucosa and in peripheral blood. According to some researchers the intensification of colonization influences the severity of inflammatory process.

AIM OF THE STUDY

To assess whether on the basis of examination of anti-H. pylori and anti-CagA H. pylori surface antibodies in blood it may be concluded that there is an intensification of H. pylori colonization in the stomach.

MATERIAL AND METHODS

The study comprised 154 children aged 5-18 years (mean 13.6 +/- 3.6 years) with alimentary tract ailments: 99 children with active H. pylori infection (Hp+) and 55 children without current H. pylori infection (Hp_). In blood there were examined anti-H. pylori surface antigens IgG class (with ELISA), anti-CagA H. pylori antibodies IgG class (with ELISA), and in gastric mucosa specimens the intensification of H. pylori colonization was tested with the use of semi quantitative method. Statistic analyses were performed.

RESULTS

Anti-H. pylori antibodies IgG class were present in the serum of 88.3% of the examined children, including in 96% of children from Hp+ group and 75% from Hp_ group. Anti-CagA H. pylori specific antibodies were found in 56.7% of children from Hp+ group and were not detected in Hp_ children. Spiral H. pylori forms were more frequently revealed in the prepyloric part of the stomach (of medium or small intensification) than in the corpus (of small intensification) (77.8% vs. 56.5%, p < 0.001). Positive correlation was demonstrated between the number of bacteria in tissue and index value of antibodies against anti-H. pylori surface antigens in serum (R = 0.45, p < 0.001) (particularly in the prepyloric part of the stomach) and high positive correlation was shown between density of spiral H. pylori bacteria in gastric mucosa bioptates and the occurrence of anti-CagA antibodies in serum (R = 0.59, p < 0.001) and index value of anti-CagA H. pylori antibodies in serum (R = 0.58, p < 0.001).

CONCLUSIONS

High concentrations of anti- H. pylori IgG class surface antibodies and occurrence of anti-CagA antibodies in blood correlate with high intensification of H. pylori colonization in the prepyloric part of the stomach.

Anti-phagocytic activity of Helicobacter pylori lipopolysaccharide (LPS)--possible modulation of the innate immune response to these bacteria

The Helicobacter pylori infections are followed by an infiltration of the gastric mucosa by neutrophils and macrophages. Accumulation of phagocytes enables them to interact with H. pylori, but a great number of infected subjects cannot eradicate these bacteria. The H. pylori inhibits its own uptake by blocking the function of phagocytes. The anti-phagocytic mechanism depends on bacterial surface structures and the presence of the cag pathogenicity island (PAI). The role of H. pylori lipopolysaccharide (LPS), during phagocytosis of these bacteria is not clear. LPS may mediate direct bacteria/phagocyte interactions and it may also regulate antibacterial activity of the phagocytes. In this study we investigated the influence of H. pylori LPS on phagocytosis of these bacteria. The H. pylori LPS inhibited an ingestion of these microbes by human peripheral blood granulocytes. This was correlated with a diminished ability of phagocytes to reduce MTT-tetrazolium salt. The anti-phagocytic effect of H. pylori LPS was reduced by recombinant lipopolysaccharide binding protein (rLBP). It is possible that in vivo H. pylori LPS may diminish elimination of these bacteria from the gastric mucosa promoting an infection persistence. However, LBP may modulate the uptake of H. pylori due to neutralization of anti-phagocytic effect of its LPS.

[Comparable evaluation of usefulness of traditional methods and polymerase chain reaction technique in detection of Helicobacter pylori infection]

H. pylori is a well recognized pathogenic factor of chronic gastritis and class I carcinogen. Specimens are collected on gastroscopy performed due to clinical symptoms suggesting upper alimentary tract organic disease for pathomorphological examinations and for the estimation of the presence of H. pylori infection in urease test, histological examination in Giemsa staining method or in a culture. The aim of the project was to compare the detection of H. pylori in gastric mucosa in children by conventional method and polymerase chain reaction technique (PCR).

MATERIAL AND METHODS

The study comprised 137 children and adolescents, aged 5-18 years (mean 13.2 years), in whom basing on the evaluation of the level of serum anti-H.pylori antibodies (ELISA), urease test and histological examination (HE), H. pylori infection was diagnosed or excluded. H. pylori genes: ureA, vacA, cagA were identified in gastric mucosa specimens with PCR method.

RESULTS

On the grounds of standard methods H. pylori was detected in 86 (62.8%) and excluded in 51 (37.2%) children. UreA gene was detected in gastric mucosa in 82 (95.3%) children with H. pylori (Hp+) and in 8 (15.7%) without H. pylori (Hp-) infection (p < 0.001). CagA H. pylori gene was identified in 21 (24.4%) children from Hp+ group and in 1 (2%) from Hp- group (p < 0.001), and vacA gene in 23 (26.7%) and 6 (11.8%) (NS), respectively. H. pylori strains type I (cagA+/vacA+) were found in gastric mucosa of 15 (17.4%) Hp+ patients. CONCLUSIONS. Testing of H. pylori genes (particularly ureA gene) with PCR technique in mucosa bioptates enables to diagnose H. pylori infection even in patients with the infection not detected with standard methods.

Mannan-binding lectin in children with chronic gastritis

The involvement of mannan-binding lectin (MBL) insufficiency in the pathogenesis of chronic gastritis (CG) in children was investigated. Blood samples were collected from 78 paediatric patients suffering from CG associated with Helicobacter pylori infection (group Hp(+)) and from 41 with the disease not associated with such an infection (group Hp(-)). Control group consisted of 77 children. The frequency of mbl-2 gene mutations and serum protein concentrations did not differ significantly in both groups as compared with controls. An expression of mbl-2 gene in gastric biopsies of CG patients was demonstrated. It was found to be stronger in H. pylori-infected children. The results presented in this paper suggest that MBL deficit/dysfunction probably does not contribute to an increased risk of CG (both associated and not associated with H. pylori infection) in children. However, MBL opsonic effect and/or the lectin pathway of complement activation may be taken into account as possible host defence mechanisms in gastric patients.

[Assessment of postvaccinal response in children past pertussis]

In the nineties, despite high percentage of vaccination of children, from 86% to 99% dependently on the region, there came to the increase of whooping cough cases. Until then infants and children to the age of 5 years suffered from this disease, whereas in the last decade the number of cases increased mainly among children over 5 years of age, who were subjected to full cycle of vaccination against whooping cough. Searching for the causes of such epidemiologic situation the following suggestions have been given: change of the bacteria antigenicity, the phenomenon of postvaccinal immunity extinction, immune system mechanisms disorders and groundless excuse from vaccination. The study estimates parameters of postvaccinal response to immunization with selected vaccines in children post whooping cough.

Potential role of LPS in the outcome of Helicobacter pylori related diseases

In this study we asked a question whether H. pylori LPS with or without LewisXY (Le) determinants as well as LBP (lipopolysaccharide binding protein) and sCD 14 molecules recognizing bacterial LPS may be involved in atherogenesis. Sera from 57 patients with coronary heart disease (CHD), 27 H. pylori infected dyspeptic patients-H.p.(+) and 49 healthy controls (HC) were tested for IgM and IgG to H. pylori LPS expressing LeX (LPS LeX) or LeXY (LPS LeXY) determinants and to a glycine acid extract (GE). Immune complexes (ICs) of Lewis antigens and specific IgM or IgG were also determined. The prevalence of anti-GE IgG and IgA was significantly higher in CHD as compared to HC and the same as in the H.p.(+) group. The highest levels of anti-GE IgG were detected only for CHD group. CHD patients showed upregulation of IgG to LPS LeX and LeXY. In contrast, an upregulation of IgM to such LPSs was found for healthy subjects. The levels ofLeY-anti-LeY IgG ICs were higher in CHD patients than in healthy controls similarly to the levels of LBP. There was no difference in sCD14 concentration between CHD and HC groups. The results obtained in this study indicate that H. pylori infections may be the risk factors of atherosclerosis due to: 1) an enhanced humoral response to H. pylori surface antigens, 2) a host predisposition to respond to Lewis determinants present in H. pylori LPS by IgG, 3) increased levels of serum LBP.

Natural mannose-binding lectin (MBL) down-regulates phagocytosis of Helicobacter pylori

Considering the role of lectin-carbohydrate interactions between Helicobacter pylori bacteria and the host cells we addressed the question on how mannose binding lectin - MBL, present in human plasma, may influence the phagocytosis of H. pylori by peripheral blood granulocytes. For phagocytosis assay the granulocytes separated from peripheral blood of healthy H. pylori-seronegative donors were used. Phagocytosis was estimated by fluorescence assay using FITC-labelled H. pylori cells. The MBL level in the serum samples as well as MBL-binding to H. pylori bacteria were estimated by ELISA. In this study all H. pylori isolates bound recombinant mannose binding lectin-MBL as shown by ELISA. The ingestion of H. pylori bacteria in the medium with human serum depleted in natural MBL (nMBL) was more intensive than in the medium with complete serum containing nMBL. Moreover, the ingestion of H. pylori bacteria in the medium with complete serum was increased by an addition of anti-rMBL IgG. The results indicate that interaction of bacterial and host lectins may regulate the phagocytosis of H. pylori bacteria and in this way influence an outcome of the infection caused by these microbes.

[Mucus physicochemical properties in children with ulcerative colitis]

The aim of the study was to estimate colonic mucus physicochemical state in children with ulcerative colitis. Investigations were performed in 36 children, aged 10-17 years, allotted into three groups dependently on the severity of the disease. The severity of the disease was estimated basing on Truelove-Witts criteria. Mucus analysis was performed with polyacrylamide gel electrophoresis (SDS-PAGE), electron paramagnetic resonance (EPR) and spectrophotometric method. Mucus fraction dissolved in normal saline was subject of investigations. Protein content was determined in this fraction with Lowry's method. The obtained results demonstrated different mucus solubility dependent on the severity of the disease. Mucus protein concentration increased whereas mucus viscosity decreased with the severity of the disease. Colonic mucus physicochemical properties change dependently on the disease severity. Determination of soluble protein fraction in mucus may be a useful marker in the estimation of the disease severity.

[Peptic ulcer disease etiology, diagnosis and treatment]

Authors in this article present etiology, clinical manifestations, diagnostic procedures and treatment of peptic ulcer disease in children and adults. Increased gastric acid output, Helicobacter pylori, NSAIDs and stress are the basic risk factors in peptic ulcer disease. H. pylori infection is a widely known risk factor in peptic ulcer disease and influences diagnostic and treatment procedures. Primary ulcer disease concerns mainly duodenum and is accompanied by H. pylori infection. Gastroscopy and Helicobacter tests are the only reliable procedures to diagnose peptic ulcer disease. Nowadays the most important aim in peptic ulcer treatment is the H. pylori eradication. Therapy with two antibiotics and a protein pomp inhibitor eradicates the bacteria, treats the ulceration and lowers the number of ulcer recurrence. In non-infected H. pylori ulcers or in a long-term treatment protein pomp inhibitors and H2-inhibitors are effective as well in gastroprotective therapy.

[Irritable bowel syndrome--pathogenesis, management]

Irritable bowel syndrome creates many diagnostic and treatment difficulties in a general practitioner practice as well as in a specialist practice. Etiopathogenesis of this illness still elicit some controversy. In a diagnostic process, apart from an organic basis excluding, the most important is a medical history of a patient because of the fact that a right symptoms interpretation usually allows a correct diagnosis establishment. A treatment is in its premise a symptomatic treatment, is long-lasting and based on a mutual trust between a doctor and a patient. Basic information concerning this illness is presented in this article.

[Neutrophils and selected cytokines in ulcerative colitis pathomechanism]

The aim of the study was to assess receptor CD11b and CD62L expression on neutrophils and IL-1beta, IL-6 and IL-8 level in children with ulcerative colitis. Thirty children aged 8-17 years were included in the study. The investigations were performed in the acute phase, prior to the treatment and during remission, 2 months after clinical improvement was obtained. The control group consisted of 12 children with chronic obstipation. IL-1beta, IL-6 and IL-8 serum level and receptor CD11b expression, especially on resting neutrophils, in children with severe and moderate course of the disease were statistically significantly higher; whereas CD62L expression was significantly lower in comparison with the controls and got back to normal during remission. Increased IL-1beta level was observed only in children with severe disease course. In children with mild process the results of the investigations were similar to the control group. In children with severe disease activity the proinflammatory cytokines levels in serum were elevated. The neutrophils in children with severe course of the disease manifested priming in peripheral blood before leaving the circulation.

[The role of Candida sp. in etiopathogenesis of esophageal, gastric and duodenal mucosa inflammation in children]

The aim of the study was to demonstrate morphological traits of Candida-induced upper alimentary tract mucosa inflammation. The material for the study comprised 18 children aged 4 to 18 years treated at the I Department of Paediatrics and Gastroenterology, Institute Polish Mother Health Centre. In these children positive mycologic cultures were obtained from alimentary tract inflammed mucosa sections. Upper alimentary tract endoscopy was performed and macroscopic and microscopic evaluation was made. Children with excluded H. pylori infection, reflux disease, lambliosis and allergy were included into the investigated group. Savara-Muller's classification was used for oesophageal mucosa inflammation evaluation, whereas gastric and duodenal mucosa inflammation were assessed according to Tytgat.

RESULTS

the most frequent macro lesions concerned simultaneously gastric and duodenal mucosa (44.46%). 27.77% of patients demonstrated oesophagitis, gastritis and duodenitis. In histopathological examination inflammatory lesions in oesophageal mucosa were observed in 38.88% (most frequently I degree). Chronic gastritis was found in all children, non-active in 11 and active in 7. Duodenal mucosa demonstrated traits of chronic active inflammation in 8 children and chronic in 5 of them.

CONCLUSIONS

Candida fungi may be an etiopathogenetic factor of oesophageal, gastric and duodenal mucosa inflammation, Candida-induced mucosa inflammation is most frequently of chronic nature.

[Clinical course of toxocarosis in children]

The aim of the study was to monitor the clinical course of T. canis infection in children with particular consideration of the estimation of infected children's immune system. The study comprised 52 children, aged 3 to 18 years, diagnosed and treated at the I Department of Paediatrics and Gastroenterology, Institute Polish Mother Health Centre, in whom infection with Toxocara canis larva was confirmed with serologic test. The control group included 38 children, aged 3 to 16 years in whom no infection with this parasite was detected in serologic test. In the investigated children subjective and physical examinations were performed, clinical symptoms, changes in organs, haematological, biochemical investigations and selected parameters of humoral and cellular immunity were analysed. In children with toxocarosis most frequently not localized abdominal pain, subfebrile body temperature and generalized lymphadenitis were observed. Significantly higher percentage of eosinophil cells and immunoglobulin E serum concentration with decreased percentage of lymphocytes CD3+, CD4+ and CD4/CD8 ratio were found in the investigated children. Toxocarosis diagnosis is difficult because its clinical symptoms are differentiated and not characteristic, what requires broadening of differential diagnosis concerning numerous entities.

Serological differentiation of Helicobacter pylori CagA(+) and CagA(-) infections

Many Helicobacterpylori strains causing gastroduodenal diseases have a cagA gene encoding CagA protein, a virulence factor of these bacteria. Anti-CagA antibodies produced by the majority of people infected with CagA(+) strains can indicate such an infection. In this study, the efficacy of three immunoenzymatic tests for detecting CagA(+) and CagA(-) infections were compared: immunoblot (Milenia ID Blot H. pylori IgG; MB) and ELISA conducted either with a recombinant immunodominant fragment of CagA (rCagA) or the full-length CagA molecule (flCagA). The 13C-urea breath test (13C-UBT) was used for establishing H. pylori status. The serum samples from 157 individuals were used for serodiagnosis. H. pylori CagA(+) infection was detected in H. pylori-infected individuals with similar frequencies by MB (64%) and flCagA-ELISA (60%) and a little less frequently by rCagA-ELISA (53%). There was a high coincidence between the negative results of these three tests for H. pylori-uninfected individuals with no anti-CagA IgG in the serum (96-100%). The results show that rCagA-ELISA and, especially, flCagA-ELISA are easy, inexpensive and useful noninvasive assays for the discrimination of CagA(+) and CagA(-) H. pylori infections in subjects examined by urea breath test.

[Assessment of the response of peripheral blood mononuclear leukocytes on Helicobacter pylori infection in children]

In the study the proliferative response of peripheral blood mononuclear leukocytes (PBML) from children with chronic dyspepsia (chr. d) to H.p. antigens was investigated. From 38 children aged 7-18, with chr. d., blood was collected just before upper GI endoscopy. Twenty one patients were found to be H.p. (+). PBML were used for the cultures and were stimulated with heat-killed H.p. G27 bacteria, heated and unheated glycine extract (GE) of H.p. G27 or with H.p. LPS containing Lewis X and Lewis Y determinants, in the presence or absence IL-2. The cell proliferation was estimated on the basis of [3H] - thymidine incorporation. In the cultures, the phenotype of responding cells was determined by an EIA with monoclonal antibody to human CD3, CD4 and CD8. PBML from patients H.p. (-), responded to killed H.p. bacteria and to heated GE more frequently and more intensively than PBML from the H.p.(+). IL-2 enhanced PBML response to these antigens. Unheated GE did not induce PBML proliferation even in the cultures with IL-2. LPS alone induced proliferation of PBML from 3 patients (2 H.p. - and 1 H.p.+). However, in the presence of IL-2, LPS induced proliferation of PBML from 15 patients. In the cultures of PBML stimulated with whole bacteria or heated EG, T cells dominated. In the cultures of PBML from H.p. (+) we found a higher percentage of CD8 cells in comparison with the cultures of PBML from H.p. (-). Data demonstrate a significant variation in the response of PBML from dyspeptic children to H.p. antigens.

Detection of specific Helicobacter pylori DNA and antigens in stool samples in dyspeptic patients and healthy subjects

In this study stool samples from dyspeptic patients and healthy subjects were used for detection of specific Helicobacter pylori antigens and DNA by immunoenzymatic test (PPHpSA) and semi-nested PCR (ureA-PCR), respectively. The H. pylori status was estimated by invasive endoscopy-based rapid urease test and histology or noninvasive urea breath test (UBT), and by serology (ELISA, Western blot). The coincidence of H. pylori-negative invasive tests or UBT and negative antigen or DNA stool tests was very high (mean 95%). The PPHpSA results were found positive for 56% and ureA-PCR for 26% of individuals with H. pylori infection confirmed by invasive tests or UBT. The detection of specific H. pylori antigens and especially DNA in feces is not sufficient as a one-step diagnosis of H. pylori infection.

[Intrahepatic and peripheral blood NK cells in patients with chronic hepatitis C]

The aim of this study was to evaluate the correlation between NK (natural killers) cells in an inflammatory infiltration of the liver and in peripheral blood in children with chronic hepatitis type C.

MATERIAL AND METHODS

The study comprised 25 children with chronic hepatitis type C. The control group comprised 10 children with no liver disease in past medical history and normal activity of aminotransferases. In the study group, liver biopsy specimens were evaluated by histopathology and immunomorphology - the presence of NK cells present in the inflammatory infiltrate was determined. In all children the percentage and absolute count of NK cells in peripheral blood was evaluated by flow cytometry, as well as the activity of NK cells in relation to leukaemic cells of erythroleukemia K-562 without stimulation and after the stimulation with IL-2 (in vitro).

RESULTS

In the studied group of children NK cells constituted 6.07 +/- 3.92 % of cells present in liver infiltrate. In peripheral blood NK cells constituted 11.68 +/- 6.73 % of white blood cells, and their absolute number was 241.08 +/- 128.56 /ml. The cytotoxic activity of NK cells in dilution E:T 25:1 was - 91.8 +/- 1.07 % and in dilution E:T 12.5:1 - 6.72 +/- 3.68 %. After stimulation with IL-2 it was 92.8 +/-1.01 % and 7.58 +/- 3.95 %, respectively. The number of NK cells in peripheral blood and cytotoxic activity of NK cells in the studied group did not differ from that of the control group. There was a positive correlation between the percentage of NK cells in the liver infiltrate and the absolute number of NK cells in the peripheral blood and between percentage of NK cells in the inflammatory infiltrate and cytotoxic activity of NK cells in peripheral blood, stimulated and non-stimulated with IL-2 in proportion E:T 12.5:1.

CONCLUSIONS

Positive correlation between the number of NK cells in peripheral blood and liver infiltrate suggests the possibility of evaluating NK cells involvement in the pathogenesis of chronic hepatitis type C in children on the basis of peripheral blood tests.

A potential double role of anti-Lewis X antibodies in Helicobacter pylori-associated gastroduodenal diseases

In this study, we found Lewis X (Le(x)) determinants on 68% of Helicobacter pylori isolates from patients with chronic gastroduodenal diseases. Anti-Le(x) IgG were detected more frequently in the sera from dyspeptic children and adults (45 and 46%), with or without proved (culture) H. pylori infection, than in the sera from healthy individuals (14% and 25%). In contrast, the prevalence of anti-Le(x) IgM was higher in the groups of healthy individuals than in the groups of dyspeptic patients. Moreover, anti-Le(x) monoclonal antibody of IgM class enhanced the uptake of Le(x)(+) but not Le(x)(-) H. pylori isolates by phagocytes. In the sera from some dyspeptic patients, we detected Le(x)-anti-Le(x) IgG immune complexes (Le(x) ICs). There was a great difference between children and adults as regards the presence of Le(x) ICs. The immune complexes were found in the sera from nine out of 29 (27%) H. pylori-infected and three out of eight (37%) uninfected adult dyspeptic patients. In comparison, Le(x)-anti-Le(x) IgG ICs were detected only for two out of 18 (11%) H. pylori-infected children. Le(x) ICs were not found in the sera from healthy individuals. Our results suggest that anti-Le(x) IgM may play a protective role in H. pylori infections. In contrast, anti-Le(x) IgG and particularly Le(x)-anti-Le(x) IgG ICs might contribute to the pathogenesis of chronic H. pylori infections.

[IgG and IgA immunoglobulins in helicobacter pylori infections of children with chronic dyspepsia before and after two week triple drug therapy]

The aim of this study was to investigate whether serological techniques, ELISA and Western blot, are useful in monitoring treatment of H. pylori-associated chronic dyspeptic symptoms in children. We observed a correlation between a decrease in the anti-H. pylori IgG titer and an effective treatment. So, our results suggested that the ELISA assay conducted with a glycine H. pylori extract can be a good noninvasive assay for monitoring the effectiveness of the therapy. By using the Western blot method, we showed some variation in the specificity of anti-H. pylori IgG produced before and after treatment. However, this variation was not correlated with the effectiveness of the therapy.

Proliferative activity of gastric epithelial cells in Helicobacter pylori infected children

Helicobacter pylori infection has been associated with gastric carcinogenesis. Gastric epithelial cells proliferative rate is accelerated in H. pylori infected adult patients. Our study was performed to evaluate proliferative cell activity in gastric epithelium in the course of H. pylori infection in the early stage of its natural history. Gastric antral biopsy specimens were obtained from thirteen H. pylori positive and seven negative children. To assess replication rates we used nucleolar organiser regions staining with colloidal silver nitrate technique (AgNOR). The number of AgNORs per nucleus, area of single AgNOR, and the quotient of these two parameters (AgNOR content) were analysed. The mean area of AgNOR was lower in H. pylori positive than in negative children. Conversely, both the mean number of AgNOR per nucleus and AgNOR content were higher in infected than non infected subjects. These results show accelerated proliferation of gastric antral epithelial cells in the course of H. pylori infection in children. Such alteration of cell replication occurring in an initial phase of natural history of long lasting infection provides an explanation for the association between acquisition of H. pylori infection in the first years of life and the development of gastric cancer.

Mallory-Weiss syndrome in children

The aim of the study was to evaluate the incidence and the etiology of Mallory-Weiss syndrome in children. The study population comprised 2720 children aged 5 months to 18 years who had undergone upper gastrointestinal endoscopy. Mallory-Weiss syndrome was diagnosed in eight (0.3%) of the examined children. Endoscopic examination in five of them revealed linear mucosal tears, mostly above and in one case also below the gastroesophageal junction. In three children a linear scar in the lower portion of the esophagus was seen. No signs of active bleeding were revealed in any of the cases. In four children, Mallory-Weiss syndrome was accompanied by gastritis and duodenitis; two of these children had Helicobacter pylori infection. The concomitant diseases were H. pylori-positive duodenal ulcer (1), bronchial asthma and gastroesophageal reflux disease (1), carbon monoxide poisoning (1). In one case Mallory-Weiss syndrome was diagnosed in early pregnancy. Mallory-Weiss syndrome should be considered, along with others, as a cause of acute upper gastrointestinal bleeding in children. There is a great variety of etiologic factors in Mallory-Weiss syndrome in children.

Anti-Lewis X IgM and IgG in H. pylori infections in children and adults

A role of autoimmune processes in the pathology of Helicobacter pylori infections has been suggested. The Lewis determinants present in LPS molecule of H. pylori bacteria have been indicated as the cause of antigenic mimicry. In this study, the prevalence of IgM and IgG antibodies to Lewis X antigen in the sera from children and adults, with or without dyspepsia, infected or not infected with H. pylori, seropositive and seronegative for anti-H. pylori IgG were determined immuno-enzymatically (ELISA). Our results revealed that humans may produce anti-Lewis X antibodies, particularly of IgM class, in the absence of H. pylori infection or H. pylori independent dyspepsia. The production of such antibodies, by healthy children who had never been infected with H. pylori suggested that anti-Lewis X antibodies may occur naturally.

Systemic humoral response to Helicobacter pylori in children and adults

In this study we compared the development of anti-H. pylori humoral response in adults and children. Two antigens: H. pylori acid glycine extract (GE) and recombinant cagA were used for ELISA and Western blot. Anti-GE IgG were detected in all and anti-cagA IgG in about 50% of H. pylori infected adults and children. The prevalence of anti-GE and anti-cagA IgG in the sera from H. pylori-uninfected children with gastritis/gastroduodenitis was lower than in the sera from healthy adult blood donors. Serum IgA were demonstrated for 71% of H. pylori-infected adults and for a smaller proportion (about 30%) of uninfected adult patients or normal subjects. Such antibodies were detected neither for infected nor for uninfected children. There was an evident difference between the proteins of H. pylori glycine extract recognized by antibodies present in the sera from H. pylori-infected children and adults. The antigen of molecular weight over 107 kDa was recognized exclusively by the sera from 30% of H. pylori-infected adults. The 80-107 kDa bands were recognized more frequently by the sera from adults than from children. In contrast, sera from infected children more frequently than sera from infected adults reacted with the bands of 14 kDa, 19 kDa and 26 kDa. The H. pylori antigens recognized by IgG, produced by infected children and adult patients, should be taken into consideration in the developing of tests for serodiagnosis of H. pylori infection.

Serum IgG antibodies in children and adults reacting with Helicobacter pylori lipopolysaccharides

The presence of IgG antibodies reacting with Helicobacter pylori lipopolysaccharides (LPSs) in sera from children and adults diagnosed as H. pylori-infected, as well as healthy persons, was tested. There was no correlation between the production of antibodies reacting with H. pylori surface proteins and LPSs. Also no correlation between reactivity of tested sera with H. pylori antigens and deep rough mutant (Re types) enterobacterial LPSs was revealed. The prevalence of anti-LPS IgG in randomly selected children was relatively high.

Attachment of Helicobacter pylori strains to human epithelial cells

The aim of the study was to characterize several clinical isolates of H. pylori as regards the activity and specificity of their haemagglutinins and the involvement of surface sialic acid-specific and heparin-binding compounds in the adhesin of the bacteria to human epithelial cell lines. Although H. pylori strains caused haemagglutination (HA) of sheep erythrocytes, they differed markedly by activity and specificity. On the basis of haemagglutination inhibition study three types of H. pylori strains could be distinguished. The HA of Type I strains was inhibited with fetuin/mucin but not asialofetuin/asialomucin. The HA activity of Type II strains was inhibited with fetuin/mucin and asialofetuin/asialomucin. The HA of Type III strains was not influenced by any of these inhibitors. In vitro, H. pylori strains bound to the cells of human epithelial lines: HeLa, Kato-3, Ags. However, various compounds mediated the binding of H. pylori types distinguished by HA, to epithelial cells. The interaction of some of H. pylori strains with epithelial cells was mediated by bacterial sialic acid-binding compounds. The majority of H. pylori strains used heparin-binding surface compounds to attach to epithelial cells. Clinical H. pylori strains differ by the compounds used in adhesin to epithelial cell lines, however, this process also depends on the expression of appropriate receptors on the host cells.

Serological indicators of Helicobacter pylori infection in adult dyspeptic patients and healthy blood donors

The levels of IgM, IgG and IgA antibodies reacting with two Helicobacter pylori antigens (glycine acid extract (GE) and a recombinant CagA protein) were determined in the sera from adult dyspeptic patients, positive (H.p.(+)) or negative (H.p.(-)) for H. pylori urease/culture, and from healthy blood donors. All sera were also examined against GE by Western blot (Immunoblot) technique. Similar levels of anti-GE IgG were detected in the sera from all H.p.(+) and almost all H.p.(-) patients and from over 40% of the healthy volunteers. In contrast, higher levels of anti-GE IgA were found in the sera from patients than that from healthy subjects, although such antibodies were not detected in the sera from 30% of the H.p.(+) patients. In general, our results suggest that a combination of ELISA and immunoblot may be more sensitive in the detection of H. pylori infection in dyspeptic patients than the examination of biopsy specimens by culturing or histology.

Electron microscopic study of association between coccoid forms of Helicobacter pylori and gastric epithelial cells

OBJECTIVE

To investigate the relationship between helical and coccoid forms of Helicobacter pylori and gastric epithelial cells.

METHODS

Gastric antral and body biopsies were obtained from eight children, aged 10-17 yr, who underwent diagnostic gastroscopy. Specimens were processed for electron microscopy. The location of organisms and ultrastructural features were assessed with a transmission electron microscope.

RESULTS

We observed two morphological forms of bacteria in three of eight H. pylori-positive patients. Helical forms were localized only in the proximity to unchanged or variously damaged mucous cells, but coccoid forms were present only above strongly damaged epithelial cells.

CONCLUSION

Coccoid forms of H. pylori are closely associated with damaged gastric mucous cells. Possible explanations for this phenomenon are discussed.

Morphological and immunohistochemical examinations of the dynamic changes of gastric mucosa associated with the treatment of helicobacter pylori infection in children

The aim of this study was to investigate the consequence of Helicobacter pylori eradication on gastric mucosa and antral G and D-cells. Forty children, aged 5-17 years with Helicobacter pylori infection were assessed. Helicobacter pylori was detected by a urease test and identified by serological and microbiological methods. Twenty children were again assessed after the therapy (the combination of colloid bismuth subcitrate, amoxycillin and metronidazole). Gastroscopic examination was performed and at least six bioptic specimens were taken from the antrum, body and fundus. Tissue samples, processed with the paraffin method and stained with hematoxyllin and eosin, were assessed. Monoclonal antiserum Gastrin PAP kit 516 and somatostatin PAP kit 512 (DAKO) in the peroxidase-antiperoxidase technique (PAP) have been used to detect G and D-cells. Helicobacter pylori in the gastric mucosa was demonstrated with the Giemsa method. The results show the coincidence of Helicobacter pylori infection and the count of antral G and D-cells and active chronic gastritis in children. After the treatment Helicobacter pylori was eradicated in 70% of children. In 34% of these cases the eradication was followed by a diminution of activity of gastric antral mucosa inflammation and in 20% of these children the resolution of the inflammatory infiltration in the gastric mucosa was seen. A decrease of the antral G and D-cells count and also a diminution of G/D index in these cases were observed.