Neutrophil degranulation by Helicobacter pylori proteins

Mucosal biopsy specimens from patients with Helicobacter pylori infection in gastric antrum contain an increased amount of myeloperoxidase. This study was performed to elucidate the interaction of H pylori sonicate protein(s) and neutrophils concerning myeloperoxidase release. Neutrophil degranulation with myeloperoxidase release was examined in a direct stimulating assay. Priming activity of H pylori was examined after preincubating neutrophils in sonicate, either crude or modified by heat treatment, pronase inactivation and dialysis, and stimulating with N-formyl-methionyl-leucyl-phenylalanine (fMLP) or serum opzonised zymosan (OZ). It was found that H pylori sonicate protein(s) stimulates neutrophil degranulation with myeloperoxidase release in a concentration dependent way. The activity was distinct from fMLP and capable of priming the subsequent fMLP and OZ response. Experiments with the modified bacterial sonicate suggest the activity is caused by a protein, but the findings show that non-protein molecules, for example, lipopolysaccarides were also part of the H pylori sonicate priming activity. The increased mucosal myeloperoxidase in H pylori associated disease can be a direct consequence of bacteria derived stimulation of inflammatory neutrophils.

Cross-reactive antigens shared by Pseudomonas aeruginosa, Helicobacter pylori, Campylobacter jejuni, and Haemophilus influenzae may cause false-positive titers of antibody to H. pylori

Cystic fibrosis (CF) patients suffer from many of the gastrointestinal conditions which occur in non-CF individuals, e.g., dyspepsia and peptic ulceration. These symptoms may be caused by Helicobacter pylori but could also be due to either pancreatic insufficiency or the intensive antibiotic treatment used in CF patients. Since CF patients chronically infected with Pseudomonas aeruginosa produce antibodies against a wide range of antigens, including antigens common to many other bacteria, e.g., GroEL and lipopolysaccharide, we studied, by the Western blot (immunoblot) technique, the specificity of immunoglobulin G antibodies to H. pylori in Danish CF patients chronically infected with P. aeruginosa, CF patients without P. aeruginosa infection but with Haemophilus influenzae infection, patients with dyspeptic ulcers associated with H. pylori, and patients recovering from acute Campylobacter jejuni or Campylobacter coli infection. Sera from CF patients with chronic P. aeruginosa or H. influenzae infection and patients recovering from acute C. jejuni infection cross-reacted with H. pylori antigens. A strong cross-reacting protein antigen at approximately 14 kDa and minor cross-reactive antigens at approximately 27, 30, and 60 kDa (the heat shock protein GroEL is equivalent to the common antigen of P. aeruginosa) could be demonstrated. The results of this study show that high immunoglobulin G antibody titers against H. pylori in CF patients cannot be regarded as indicating present or past H. pylori infection unless their specificity is proven by absorption studies.

Development of a PCR-based technique for detection of Helicobacter pylori

A primer-set was designed for specific detection of genes that encode for 16S rRNA of Helicobacter pylori, using direct polymerase chain reaction (PCR). The primers were selected in the hypervariable regions, derived from a complete small subunit 16S rRNA sequence of the reference strain H. pylori CCUG 17874. The primer-set amplified a 537 base pair (bp) sequence specifically from chromosomal H. pylori DNA. Amplification of purified chromosomal H. pylori DNA was achieved at concentrations as low as 1 femto gram (fg), equivalent to 5 bacteria. Furthermore, as few as 1 lysed H. pylori cell was detected by this PCR technique. The specificity of the primers was 100%, since purified chromosomal DNA was detected from all 32 various H. pylori isolates, whereas no other bacteria species were detected, whether related to Helicobacter or not. The 16S rDNA primers successfully detected H. pylori in antral biopsy specimens collected from infected patients.

Investigation of Helicobacter pylori ascorbic acid oxidating activity

Helicobacter pylori sonicate was shown to oxidize ascorbic acid. Ascorbic acid oxidation was determined by chromatography combined with electrochemical detection. Water soluble ascorbic acid oxidase activity was rather independent of pH with a pH optimum around 2. By gel filtration the oxidizing activity co-eluted with an absorbency peak at 408 nm. The relative molecular mass (Mr) was approximately 14,000. It is suggested that this oxidating activity was caused by a cytochrome c-like molecule. Ascorbic acid oxidating activity could also be extracted from bacterial membranes by detergents. Gel filtration showed several forms, the major one with a Mr = 19,000. pH optimum was 6-7. Other oxidase-positive bacterial strains like Campylobacter coli, Enterobacter cloacae and Pseudomonas aeruginosa could degrade ascorbic acid. Since ascorbic acid oxidation by Helicobacter pylori whole bacterial lysates has a pH optimum in the acidic range corresponding to pH in gastric fluid, the activity of the cytochrome c-like water soluble oxidant of Helicobacter pylori seems to be primarily important for the destruction of ascorbic acid in the gastric juice of infected patients.

Activation of phagocytes by Helicobacter pylori correlates with the clinical presentation of the gastric infection

Only a minority of subjects with Helicobacter pylori infection develop clinical gastroduodenal disease. It is unclear whether host factors or bacterial virulence properties contribute to the pathogenic mechanisms. We have previously demonstrated a 25-35-kDa protein with phagocyte stimulatory activity in bacterial sonicates. Protein preparations were made from 15 H. neutrophil and monocyte chemotaxis and chemiluminescence was assessed with cells from healthy donors in comparison with N-f-methionyl-leucyl-phenylalanine and C5a anaphylatoxin. The potency of bacterial protein(s) for induction of monocyte chemiluminescence was significantly higher for strains from ulcer patients (1 +/- 1 microgram/ml induced > or = twofold increase of control response) and chronic active gastritis (1 +/- 1 microgram/ml) compared with superficial gastritis (> 1,000 microgram/ml, p<0.05). Neutrophil activation was also significantly more potent with strains from duodenal ulcer disease. The chemotactic activity of bacterial preparations was not significantly different between the groups. We conclude that bacterial strains with pronounced activation of phagocytes are associated with the presence of clinical ulcer disease, supporting the existence of ulcerogenic strains.

Helicobacter pylori infection in children with recurrent abdominal pain

Helicobacter pylori was cultured and Helicobacter-like organisms (HLO) were seen in 6 (16%) of 37 children with recurrent abdominal pain. Five children had concomitant histological inflammation, but none had endoscopic changes. All 6 children demonstrated positive serology. Compared with the total group, they were more often from developing countries, larger families and lower social groups. Treatment with phenoxymethyl penicillin and colloidal bismuth subcitrate did not result in side effects or elevated serum levels of serum bismuth. Three children demonstrated metronidazole-resistant strains and the treatment of these children remained an unsolved problem. Among the 31 H. pylori/HLO negative children 8 (26%) demonstrated histological changes, 5 (16%) endoscopic changes and 11 (35%) had positive serology. In conclusion, pathological findings at upper gastrointestinal endoscopy are common in children with recurrent abdominal pain. Because of disconcordance between endoscopy, histology and culture, we recommend that biopsies should always be taken to clarify the diagnosis.

Neutrophil activation by Helicobacter pylori lipopolysaccharides

Helicobacter pylori-induced release of toxic substances by neutrophils could be of potential importance in the pathogenesis of gastroduodenal inflammatory diseases. Lipopolysaccharide (LPS) has the ability to induce neutrophil activation at very low concentrations. Neutrophil oxidative metabolism and enzyme release were assessed after stimulation of neutrophils with various preparations of LPS from H. pylori and compared with that obtained with Salmonella typhimurium LPS. No direct activation of neutrophils by LPS was observed. Preincubation with LPS showed a significant priming for increased activity on subsequent stimulation, particularly with rough-form LPS. The potency of H. pylori LPS was 10-fold lower than that of S. typhimurium LPS, probably reflecting the unique biochemical structure of H. pylori LPS. Chronic low-grade stimulation by H. pylori LPS in the gastric mucosa may render neutrophils primed for the excessive release of detrimental substances into the tissue on stimulation by other mediators.

The humoral immune response to Helicobacter pylori infection in children with recurrent abdominal pain

The systemic humoral immune response to Helicobacter pylori antigens was investigated in 36 children with recurrent abdominal pain (RAP). H. pylori was cultured and Helicobacter-like organisms (HLO) were seen in six children, three of whom had active and two inactive chronic gastritis. None of these children had endoscopic abnormalities. All sex children had increased IgG antibodies to heat-stable H. pylori antigens which were of the IgG1 and IgG3 subclasses. Using six other IgG tests, four of which were commercially available, two to five H. pylori-positive children were found seropositive. Five of six H. pylori-negative children with inactive chronic gastritis and no endoscopic abnormalities had increased IgM antibody levels in addition to increased or borderline increased IgG antibody levels to H. pylori, indicating activity in a chronic H. pylori infection. Five children without H. pylori and with no morphological changes, but with gastritis or duodenitis by endoscopy, had significantly lower IgG and IgA antibody levels compared to other groups. Six of nineteen children without H. pylori, and with no morphological or endoscopic changes had increased IgG and IgM antibody levels to H. pylori. All H. pylori-negative children were seronegative by the four commercial kits. Overall, 12 (33%) of 36 children with RAP were either H. pylori positive by culture and microscopy or had increased IgG antibody levels to H. pylori, which is significantly different from the 10-14% seropositive rate of asymptomatic children. H. pylori may therefore be a cause of RAP in one quarter to one third of the children with RAP in whom other etiologies of RAP are excluded. Further studies on a large number of children are needed for an extended evaluation of the humoral immune response to H. pylori and for further examination of commercial kits which seem to give a high number of false-negative results.

Evaluation of eight commercial kits for Helicobacter pylori IgG antibody detection

Eight commercial kits and an in-house ELISA for detection of IgG antibodies against Helicobacter pylori were evaluated for their use in diagnosis of H. pylori infection and in epidemiological research: Helico-GTM (Porton-Cambridge), G. A. P. test (Bio-Rad), H. pylori antibodies ELISA (Biometra), Anti-H. pylori IgG EIA (Roche), 2nd generation H. pylori EIA (Roche), Anti-H. pylori MTP-assay (Roche), Pylori stat test kit (Whittaker), Pyloriset latex agglutination kit (Orion), and the in-house ELISA based on heat-stable antigens. Fifty-four patients with dyspepsia (31 H. pylori positive by culture or microscopy) and 68 asymptomatic persons were tested. Sensitivities for the eight kits were 71%, 77%, 90%, 84%, 87%, 94%, 90%, 87%, and 87%, specificities were 74%, 65%, 74%, 74%, 83%, 83%, 70%, 65%, and 65%, respectively. For epidemiological use the estimated seroprevalence varied within approximately 15% in all age groups. Sensitivities and specificities obtained in different studies reveal as great differences in the results with the same kit as between results obtained with different kits in the same study. Kits with the highest sensitivities tend to be the same in all studies. It is therefore more important to test a kit in the population to which it is to be applied than to choose a specific kit.

Changing patterns among the subgroups of strains of Staphylococcus aureus of phage group II in Danish hospitals from 1961-91

During the period 1961-91 a total of 567,635 strains of Staphylococcus aureus from hospitalized patients in Denmark have been characterized according to their antibiotic resistance, site of isolation and phage type. Strains of phage group II (typed by the phages 3A, 3C, 55 and 71) have been analysed further. The occurrence of group II strains was relatively constant (approximately 16%) from 1961 until 1983. Since then the frequency of group II strains increased; in 1991 they accounted for 22.7% of all S. aureus strains isolated. Strains of group II can, on the basis of their phage types, be divided in four subgroups: 3A, 71, 71+ and the 'rest of group II'. Furthermore, within these groups strains may differ from one another in respect to their sensitivity to phages. The increased isolation of group II strains during recent years was because of an increase in strains of subgroups 71+ and the 'rest of group II strains'. In 1991 these two subgroups accounted for 89.7% of all group II strains. Furthermore, an increasing number of group II strains, 71.4% in 1991, was typable only at RTD x 100. The increase in the number of group II strains was even throughout Denmark. All four subgroups of group II have, during the observation period, become more frequently resistant to penicillin and/or tetracycline. Strains typed at 100 x RTD of subgroup 71+ and the 'rest of group II' are more frequently antibiotic resistant than the rest of the group II strains. Strains of the increasing subgroups occurred most often in abscesses.

Peptic ulcer: an infectious disease?

Since the ingestion studies by Marshall and Morris, Helicobacter pylori has been known to cause both acute and chronic infection in the human stomach activating both the cellular and the humoral immune system. It is of little or no value to evaluate the causative relationship of an infectious agent using Koch's criteria. The more recent criteria for causative relationships used in the science of epidemiology are more useful. These criteria include: (i) the characteristic of the association which is fulfilled for most cases of both duodenal and gastric ulcer; (ii) the temporal relationship which is fulfilled for duodenal ulcer and has not been investigated for gastric ulcer; (iii) the biological gradient which has been fulfilled for duodenal ulcer in a few studies but not investigated for gastric ulcer; (iv) the biological plausibility which is easily fulfilled for both duodenal and gastric ulcer; (v) the effect of an intervention which has been fulfilled for duodenal ulcer and in a few studies for gastric ulcer; and (vi) the coherence of these data with what is known about the disease which is fulfilled for both duodenal and gastric ulcer. Even though there is no need for all criteria to be fulfilled, further studies are necessary to confirm the temporal relationship between H. pylori and peptic ulcer, and the biological gradient of H. pylori in relation to the gastric ulcer. Even so, there is a strong indication that most of the peptic ulcers, apart from those caused by non-steroid anti-inflammatory drugs and Zollinger-Ellison-like syndromes, are caused by H. pylori infection.

Activation of human phagocytes by Helicobacter pylori. A novel interaction with neutrophils and monocytes distinct from that of N-formylated oligopeptides

Sonicate proteins from Helicobacter pylori activate human neutrophils and monocytes for chemotactic and oxidative burst responses. The molecular nature of this activity and its interaction with the phagocyte membrane is unknown. Cross-stimulation experiments were performed with human neutrophils and monocytes preincubated in H. pylori sonicate and subsequently stimulated with the established and characterised stimuli N-f-methionyl-leucyl-phenylalanine (fMLP), the complement split product C5a (in zymosan-activated serum, ZAS), and phorbol-myristate-acetate (PMA). Checkerboard experiments confirmed the sonicate to be truly chemotactic, whereas no chemokinetic activity was demonstrated. At high concentrations of sonicate (1 mg/ml), a depressed chemotactic and oxidative burst response was observed, whereas the viability was > 98%. At lower concentrations (0.01-0.1 mg/ml), only weak deactivation could be induced for monocytes, i.e. the cells had a normal function. With neutrophils, even low concentrations of sonicate depressed the oxidative burs responsiveness. However, the reduced activity was unrelated to the stimulus applied indicating that H. pylori protein(s) activate human neutrophils and monocytes by a membrane binding site distinct from that of previously described receptors.

Comparison of four second generation kits for detection of IgG antibodies against Helicobacter pylori in adults

Four serological kits for detection of IgG antibodies against H. pylori were tested on 132 adult patients with dyspeptic symptoms. Presence of H. pylori infection was established when either culture or microscopy of gastric biopsies were positive. The prevalence of H. pylori infection was 55% in the test population. With Anti-H. pylori MTP-assay (Roche), Pylori stat test kit (Whittaker), HM-CAP (Enteric Products Inc.) and Pyloriset EIA-G (Orion) the sensitivities were 97%, 95%, 81% and 68% respectively, the specificities were 53%, 56%, 71% and 69% respectively, the positive predictive values 72%, 74%, 79% and 74% respectively and the negative predictive values were 94%, 92%, 79% and 64% respectively.

Survival and ultrastructural changes of Helicobacter pylori after phagocytosis by human polymorphonuclear leukocytes and monocytes

Few studies have been carried out on the phagocytosis and killing of Helicobacter pylori by both polymorphonuclear leukocytes (PMNs) and monocytes. In this study, H. pylori was incubated for up to 60 min either alone or with phagocytes in the presence or absence of human serum. Both non-immune serum and immune serum were used. Reduction in the number of H. pylori, which corresponds to the killing of H. pylori, was analysed by a colony count and ultrastructural changes were studied by electron microscopy. No reduction in the number of H. pylori was found when the bacteria were incubated alone or with phagocytes in the absence of serum. It is remarkable that unopsonized H. pylori was phagocytosed. When immune serum was added to the suspensions of bacteria and phagocytes, the killing rate of H. pylori was found to depend on the ratio of H. pylori to phagocytes. Thus an excess of monocytes reduced the number of H. pylori, whereas an excess of PMNs resulted in complete killing of H. pylori. On incubation with PMNs and serum, ultrastructural changes were observed in the majority of the bacteria whether they were phagocytosed or not. Controls without serum did not show any changes in the morphology of H. pylori, indicating that components in the serum play an important role in the phagocytosis and killing of H. pylori. In contrast, several of the phagocytosed bacteria were found to be unaffected after incubation with monocytes and serum. Such preparations often contained large aggregates of platelets surrounding unaffected H. pylori. In the gastric mucosa, H. pylori is often found in excess as compared to the phagocytes. If these results can be compared to the situation in vivo, the phagocytes seem to be ineffective in the killing of H. pylori, and other immune mechanisms may therefore be of importance for the elimination of H. pylori from the gastric epithelium. The possible intracellular survival of H. pylori should be taken into account when treatment regimes for H. pylori infections are chosen.

Activation of human phagocyte oxidative metabolism by Helicobacter pylori

A characteristic feature of chronic antral gastritis is the abundant inflammatory response in close association with Helicobacter pylori, but the immunopathological mechanisms of tissue damage are unknown. Because reactive oxygen radicals have been implicated in the tissue damage of other chronic inflammatory disorders, we investigated the potential ability of H. pylori sonicate to influence the oxidative burst responsiveness of human polymorphonuclear leukocytes and monocytes. For both cell types, a dose-dependent stimulation in a chemiluminescence system was observed. Furthermore, preincubation in sonicate caused a marked priming of the cells to subsequent stimulation with the oligopeptide N-f-methionyl-leucyl-phenylalanine and phorbol-myristate-acetate. The sonicate activity was nondialysable, completely destroyed by proteinase and resistant to heat treatment. However, dialysis of boiled sonicate significantly reduced the activity, suggesting the breakdown of a larger molecule(s) to smaller fragments still biologically active. Preliminary experiments suggest that the activity is 25-35 kilodaltons. The demonstration of a protein with stimulatory activity for production of reactive oxygen radicals by human phagocytes may contribute to the understanding of the immunopathology associated with H. pylori infection.

Prevalence of antibodies against heat-stable antigens from Helicobacter pylori in patients with dyspeptic symptoms and normal persons

Heat-stable antigens from Helicobacter pylori were investigated for the detection of serum IgG, IgA and IgM antibodies against H. pylori by an ELISA technique. Antibody titers against H. pylori were measured in 167 dyspeptic patients, of whom 96 were H. pylori positive confirmed by culture or microscopy, and in 482 controls (0-98 years). Increased IgG antibody titers were found significantly more often in dyspeptic patients with active chronic gastritis than in patients with normal morphology, as well as in H. pylori-positive patients as compared to H. pylori-negative patients, independent of the endoscopic findings. The heat-stable antigens were compared with acid glycine-extracted antigens and a high degree of concordance was found in the results obtained with the two antigen preparations. The differences in the IgA antibody titers against H. pylori between H. pylori-positive and H. pylori-negative dyspeptic patients were significant and may be useful to confirm a borderline IgG result. No differences were found in IgM antibody titer between H. pylori-positive and -negative patients. The greatest age-dependent increase in IgG and IgA antibody titers was found in children, and if a lower cut-off level is used for children than for adults, as has been proposed, the proportion of people with increased antibody titers against H. pylori would be almost constant from the age of between five and 10 years until the time between 61 and 80 years. Comparison of H. pylori IgG antibodies with IgG antibodies against Campylobacter jejuni and total antibodies against cytomegalovirus (CMV) showed a greater similarity between H. pylori and C. jejuni (R = 0.51) than between H. pylori and CMV (R = 0.22). This may possibly be caused by cross-reactions between H. pylori and C. jejuni. The H. pylori heat-stabile antigen seems not to be very different from other crude H. pylori antigens like acid glycine-extracted antigens, but purification and characterization of the antigens are needed to improve antibody assays.

IgG subclass antibodies against Helicobacter pylori heat-stable antigens in normal persons and in dyspeptic patients

Measurement of serum IgG antibodies against Helicobacter pylori seems to be useful in the diagnosis of H. pylori infections. IgG subclass antibodies against H. pylori have, however, not been investigated thoroughly. In this study IgG1, IgG2, IgG3 and IgG4 antibody levels against H. pylori were measured using an ELISA technique in 187 normal adult persons and in 174 patients with dyspeptic symptoms, of whom 99 patients were H. pylori positive. None of the IgG subclass antibody levels were better than the total IgG level for the diagnosis of H. pylori infection. The discrimination between H. pylori-positive and H. pylori-negative patients was better with IgG1, IgG2 and IgG4 antibody levels than with IgG3 antibody level. IgG2 was the IgG subclass antibody that mainly contributed to the age-dependent increase in the IgG antibody level. This sustains the suspicion that cross-reactions between lipopolysaccharide (LPS) from H. pylori and LPS from other Gram-negative bacteria may occur.

Immunoglobulin G antibodies to Helicobacter pylori in patients with dyspeptic symptoms investigated by the western immunoblot technique

Helicobacter pylori is a gram-negative, curved, rod-shaped bacterium known to cause gastritis and to be an important factor in the pathogenesis of peptic ulcers. Serological testing has recently been proposed as an aid in diagnosis of H. pylori infections. In this study, we used the Western immunoblot technique to evaluate the possibility of using one or more of the antigens from H. pylori for this purpose. Thirteen major bands and about 30 minor bands could be identified by Western blotting when sera from 53 consecutive dyspeptic patients, 27 healthy children, and 25 blood donors were evaluated. Antibodies against most of the major bands were found significantly more frequently in patients with H. pylori infections than in patients without such infections. However, antibodies against a single polypeptide were not produced by all patients with H. pylori infection. Polypeptides with molecular masses of 120, 50, and between 19 and 36 kDa seem to be the most specific polypeptides for the diagnosis of H. pylori infections. This study showed only minor differences in antigenic composition between different clinical isolates of H. pylori, and serological cross-reactions with other bacteria were limited. Major serological cross-reactions were found only with Campylobacter jejuni and with bacterial lipopolysaccharide. However, one band at 60 kDa reacted with antiserum to the Legionella micdadei common antigen, which may indicate a cross-reaction with common antigen from several other bacteria. This study demonstrates that a number of bands may be useful as antigens in serological tests after isolation and purification.

Chemotactic activity of Helicobacter pylori sonicate for human polymorphonuclear leucocytes and monocytes

The immunopathology of Helicobacter pylori associated active chronic gastritis, which is characterised by predominance of polymorphonuclear leucocyte infiltration, is largely unknown. To evaluate the role of bacterial components as inflammatory mediators ultracentrifuged sonicated preparations were made of clinical isolates of Helicobacter pylori. The crude sonicates were shown to exhibit chemotactic activity for human polymorphonuclear leucocytes and blood monocytes in a concentration dependent fashion. The potency was comparable with previously described bacterial derived cytotaxins. The cytotaxin(s) was non-dialysable and completely destroyed by proteinase. Heat treatment did not decrease the chemotactic activity, but in sonicate subjected to 100 degrees C for 15 minutes all activity disappeared after dialysis suggesting the breakdown of a larger protein to small fragments that are still biological active. By ammonium sulphate precipitation at increasing concentrations the cytotaxin(s) was selectively found in 10% ammonium sulphate saturation, and by further molecular gel separation the chemotactic activity was found in the molecular size range from 25 to 35 kDa. The demonstration of a polymorphonuclear leucocyte and monocyte cytotaxin from Helicobacter pylori sonicate may help in understanding the mucosal immune response in gastric inflammatory diseases.

Effect of selected neuroleptic agents and stereo-isomeric analogues on virus and eukaryotic cells

Chlorpromazine, cis(Z)-chlorprothixene (Truxal), and the non-neuroleptic trans(E)-chlorprothixene and trans(E)-flupenthixol were studied in vitro for possible antiviral effect on Herpes simplex virus 2 and for toxic effect on human diploid fibroblasts. Based on an enzyme-linked immunosorbent assay (ELISA) antiviral activity was demonstrated for all the compounds in the concentration range 0.39 micrograms/ml-25 micrograms/ml. A cell-toxic effect was shown in the higher concentration range for all the compounds except cis(Z)-chlorprothixene. A cell-stimulatory effect was also detected at the lower concentration range (about 3.13 micrograms/ml) for all compounds. Thus both cell stimulation and antiviral effect can be found for the same agent within the same concentration range. The results point to the possibility of creating different antiviral drugs--which would also include a cell-stimulatory activity--among psychopharmacological drugs and their stereoisomeric analogues.

The Helicobacter (Campylobacter) pylori-colonized duodenal mucosa and gastric metaplasia

Biopsies were obtained from non-ulcerated sites of the duodenum from 100 dyspeptic patients. Helicobacter (Campylobacter) pylori was cultivated from 19 of these biopsies. Active chronic duodenitis (ACD) was found in 17 biopsies and more than 5% gastric metaplasia in 20 biopsies. H. pylori as well as ACD occurred with a significantly increased frequency when more than 5% gastric metaplasia was found in the duodenal biopsies. H. pylori on metaplastic tissue without ACD was, however, seen in two cases. H. pylori was cultivated from 9% and ACD was found in 5% of the biopsies with less than 5% gastric metaplasia. Gastric metaplasia in the duodenum was found significantly more frequently in patients with endoscopic duodenitis or duodenal ulceration than in patients with normal endoscopy. No association between gastric metaplasia in the duodenum and gastric pH or serum antibodies against H. pylori was seen. This study indicates that there is an established, but not exclusive, connection between gastric metaplasia and the colonization of the duodenum by H. pylori, the most important role being played by the antral gastric mucosa rather than the duodenum.

Long-term suppression of severe recurrent genital herpes simplex infections with oral acyclovir: a dose-titration study

Twenty immunocompetent patients, four females and 16 males, with severe recurrent genital herpes (median number of recurrences the previous year 16, range (8-24] entered an open continuous long-term suppressive treatment with oral acyclovir (ACV) for 12 months. The study included a dose-titration schedule: (ACV, 200 mg x 4/1-3 months, ACV, 400 mg x 2/4-6 months, ACV, 200 mg x 2/7-9 months, and ACV, 400 mg x 1/10-12 months). Patients with recurrences on steps two and three received an alternative dose of ACV, 200 mg x 3. Otherwise patients entered the previous dose-step. Five (20%) of patients were completely free of symptoms (recurrences and abortive lesions) during the four dose-reduction periods. A further nine patients (50%) could be dose-reduced to 200 mg x 3 without symptoms. Isolates from three patients showed a decrease in virus sensitivity after ceasing treatment. In conclusion, 14/20 of treated patients could be dose reduced to 200 mg x 2-3 without selection of HSV strains showing clinically important decreases in sensitivity towards ACV.

Possible evidence of invasiveness of Helicobacter (Campylobacter) pylori

Gastric/duodenal biopsy material from 52 patients was examined immunohistochemically for Helicobacter (Campylobacter) pylori. Specimens from 34 of the patients harboured Helicobacter pylori along the mucosal surface and 13 of these featured, in addition, immunopositive material within the lamina propria. The remaining 18 biopsies were non-reactive. This observation suggests that Helicobacter pylori can penetrate the epithelium and its basement membrane, resulting in the production of specific systemic antibodies.

Oral acyclovir suppressive therapy in severe recurrent genital herpes. A double-blind, placebo-controlled cross-over study

A randomised, double-blind, placebo-controlled cross-over study was conducted in 24 patients, nine females and 15 males, with a history of more than eight recurrences of genital herpes in the past year. The patients received a first treatment course with 400 mg acyclovir or matching placebo by mouth, twice daily, for 12 weeks. After cross-over patients received alternative medication for another 12 weeks. The patients were followed without treatment for a further three-month period. During acyclovir therapy, recurrences were completely prevented in 17 patients (71%) and the remaining seven patients had nine recurrences as compared to 18 recurrences while receiving placebo. The placebo treatment did not reduce the recurrence rate. No adverse effects were attributable to the acyclovir treatment period. All virus isolates tested after treatment remained sensitive to acyclovir. Acyclovir prophylaxis of recurrent genital herpes is effective and safe. A continuous suppressive therapy with acyclovir offers a basis for a normal sexual life to those patients severely incapacitated by their disease, but once medication is stopped, patients shed virus as before suppression.