No effect of intramuscular gold therapy on serological parameters of Helicobacter pylori infection in patients with rheumatoid arthritis: a 12 month prospective study.

OBJECTIVES--To assess prospectively the influence of intramuscular gold therapy on Helicobacter pylori serology in patients with rheumatoid arthritis (RA). METHODS--Fifty patients with RA were started on intramuscular gold or chloroquine, as the control group and were followed serologically for H pylori infection for 12 months. RESULTS--Twelve patients treated with gold and eight control patients treated with chloroquine, all with serological evidence for H pylori infection, showed no significant decline of IgA and IgG anti-H pylori antibody levels or serum pepsinogen A and C levels. Total serum IgA and IgG levels declined significantly during gold therapy, while they remained unchanged during chloroquine therapy. CONCLUSIONS--Intramuscular gold therapy in patients with RA does not influence the serological parameters of H pylori infection.     

Detection of H. pylori infection by ELISA and Western blot techniques and evaluation of anti CagA seropositivity in adult Turkish dyspeptic patients

INTRODUCTIONH pylori colonizes in the mucosa of the human stomach where it establishes a long-term infection associated with acute or chronic gastric inflammation, which may progress to peptic ulcer disease, atrophic gastritis with intestinal metaplasia, …     

The course of Helicobacter pylori infection in kidney transplantation patients

BACKGROUND: Helicobacter pylori has been found to be only a minor risk factor for gastroduodenal complications in kidney transplantation patients. The aim of the study was to follow up the course of H. pylori infection in a group of immunosuppressed kidney transplantation patients. METHODS: After a median follow-up of 6.8 years, control serum samples were taken from 93 originally seropositive and 88 originally seronegative kidney transplant recipients. H. pylori antibodies of the IgG and IgA classes and serum pepsinogen I levels were measured from pretransplant and follow-up samples in parallel. In addition, CagA antibodies were measured from the baseline samples of the seropositive patients. RESULTS: 83 of the 93 seropositive patients were also cagA-positive. In addition to the 10 patients who received H. pylori eradication therapy, 27 (29%) of the 92 patients with originally elevated H. pylori IgG antibody titres showed IgG titres at normal level or levels decreased by more than 70% and below 2000 (regarded as seroreverters) after the follow-up. One of the originally seronegative patients seroconverted during the study period. After transplantation, the decrease of serum pepsinogen I values was in accordance with improved kidney function. Patients with lower serum pepsinogen I levels before the transplantation seroreverted more easily. CONCLUSIONS: A spontaneous H. pylori seroreversion occurred in 29% of the immunosuppressed kidney transplantation patients. After a successful kidney transplantation, serum pepsinogen I values declined significantly.     

Serum Helicobacter pylori IgG and IgA levels in patients with gastric cancer

The association between Helicobacter pylori and gastric cancer has been debated in the last decade and evidence for such a causal relationship has been claimed. This study aimed to detect the seroprevalence of Helicobacter pylori in patients with gastric cancer and compare it to the other cancer patients. In addition, the value of IgG and IgA in Helicobacter pylori detection was compared in patients with gastric cancer. Consecutive gastric and other cancer patients treated between 1999-2001 were prospectively studied. Serum Helicobacter pylori IgG and IgA levels were determined. Serological tests revealed IgA and IgG positivity as 53.9% and 50.9%, respectively, while 74.5% had positive results for either IgA or IgG. Serum IgA positivity was significantly higher in gastric cancer group compared to control group (p=0.02). In contrast, serum IgG positivity did not show a significant difference in both groups and either IgG or IgA seropositivity was significantly higher in patients with gastric cancer compared to control patients (p=0.04). This study revealed a higher seroprevalence of Helicobacter pylori in gastric cancer patients and IgA was a better predictor of Helicobacter pylori seropositivity in gastric cancer patients.     

Bleeding peptic ulcers and presence of Helicobacter pylori by various tests: a case-control study

BACKGROUND: Virulence factors of Helicobacter pylori are associated with peptic ulcer disease and may be also associated with bleeding peptic ulcers (BPU). AIM: To determine whether H. pylori and/or the cytotoxin-associated gene (cagA) can increase the risk of bleeding in peptic ulcers. PATIENTS: Sixty-seven patients were studied. Thirty had BPU, 20 had non-bleeding peptic ulcers (NBPU), and 17 were control subjects (NPU). METHODS: The prevalence of H. pylori was assessed by the urease fast test, histological examination, serology, and 16S ribosomal RNA and cagA gene amplification by polymerase chain reaction (PCR). RESULTS: Histology and PCR showed greater sensitivity for diagnosis of H. pylori under bleeding circumstances when compared with other tests. Association of H. pylori was greater in the NBPU group (odds ratio [OR] 4.91, P = 0.06) than in the BPU group (OR 1.27, P = NS) when compared with the control group. When the BPU and NBPU groups were compared, H. pylori was found more often in the NBPU group (OR 0.26, P < 0.10 ). The cagA-positive gene showed a similar distribution in the three groups. The titres for anti-CagA immunoglobulin A (IgA) antibodies were higher in NBPU patients (83%) than in BPU or control patients. Furthermore, anti-urease immunoglobulin G (IgG) was detected more frequently among BPU and NBPU patients. CONCLUSIONS: NBPU patients had the highest prevalence of H. pylori by PCR. It seems unlikely that either H. pylori or the cagA-positive gene act as significant risk factors for bleeding in peptic ulcers. The lower prevalence of the microorganism among patients who bleed cannot be explained as an artificial finding.     

Downward shift in serum IgM with Helicobacter pylori seropositivity

OBJECTIVE: To determine whether Helicobacter pylori infection is associated with premature immune ageing, with respect to circulating immunoglobulins. METHODS: Serum immunoglobulin classes and H. pylori anti-urease antibody were measured in 205 subjects (aged 30-89 years), obeying inclusion/exclusion criteria. RESULTS: IgM decreased (P<0.001) by 0.9 (95% C.I. 0.3, 1.4)% per year, H. pylori seropositivity having an effect equivalent to 25 years of ageing (P<0.02). IgA increased by 0.5 (0.1, 0.8)% per year (P<0.007), IgG being unaffected by age. Seropositivity had no effect on IgA or IgG. CONCLUSIONS: Increasing age and H. pylori seropositivity are each associated with a downward shift in circulating IgM. If clinical extrapolation is justified, H. pylori eradication may be important in combating susceptibility to infection in old age.     

IgG subclass response to Helicobacter pylori in patients with chronic active gastritis and duodenal ulcer.

The IgG subclass response is determined by the type of bacteria producing the infection and by genetic factors of the host. Patients with a Helicobacter pylori infection develop a specific immune response that is mainly of the IgA and IgG class. We measured the IgG subclass response in 20 patients with chronic active gastritis without a history of duodenal ulcer and 20 patients with chronic active gastritis and duodenal ulcer diagnosed by endoscopy and histology. A control group included 20 H. pylori-negative patients and 60 H. pylori-positive blood transfusion donors. Systemic IgG subclass response was measured with a modified enzyme-linked immunosorbent assay technique, using as antigen a sonicate of six different H. pylori strains. Mouse monoclonal antibodies against each of the four human IgG subclasses (IgG1, IgG2, IgG3, and IgG4) were used. The total IgG anti-H. pylori antibody titres were equal in all three H. pylori-positive groups and significantly different from that of the negative control group (p less than 0.01). The IgG subclass response in persons infected with H. pylori involved all four subclasses but was predominantly of the IgG1 and IgG2 subclasses. All of the groups with H. pylori infection had significantly higher levels of IgG1 than the negative control group, but no differences were detected among the three groups. However, the duodenal ulcer group had a significantly higher IgG2 response than the gastritis group (mean optical density +/- SEM, 0.382 +/- 0.047 versus 0.200 +/- 0.025, respectively; p less than 0.05).(ABSTRACT TRUNCATED AT 250 WORDS)     

Class-specific antibodies during follow up of patients with farmer's lung

Sequential serum samples of 13 patients with acute farmer's lung (FL) taken during a follow-up of 18-36 months, were tested for antibodies of immunoglobulin G (IgG), IgA, IgM and IgE classes against Thermoactinomyces vulgaris and Micropolyspora faeni, and compared with contemporary lung function parameters. In the acute phase, antibodies of several Ig classes were present, those of IgG and IgA being most common. At the end of the follow-up, the mean values of all antibody titres were lower than in the acute phase, and antibodies were now mostly of one or two Ig classes only. The reduction in antibody levels was most often detectable in IgG and IgA antibodies against T. vulgaris. Antibody titres correlated inversely with tested lung function parameters, especially IgA antibodies with pulmonary diffusing capacity. Our results show that a follow-up of levels of class-specific antibodies, especially of IgG and IgA gives valuable information on causative microbes and on temporal changes of the exposure.     

Prognostic role of Helicobacter pylori infection in acute coronary syndrome: a prospective cohort study

In a prospective cohort study, we evaluated the effect of Helicobacter pylori seropositivity on the risk of future adverse cardiovascular outcomes among patients with acute coronary syndrome (ACS). In 433 patients, IgA and IgG antibodies to H pylori, along with classic risk factors, including hypertension, diabetes, hyperlipidaemia, smoking and family history of coronary artery disease (CAD) were determined. Shortand long-term follow-up information on adverse outcomes, defined as recurrence of unstable angina, myocardial infarction, coronary angioplasty, coronary artery bypass graft surgery, and sudden cardiac death was obtained. None of the classic CAD risk factors correlated with incidence of either short- or long-term outcomes. Seropositivity for H pylori was significantly associated with risk of short-term adverse outcomes, and independently predicted their incidence in multivariate regression (R = 3.05, p < 0.001). Results failed to show such an association between H pylori seropositivity and long-term adverse outcomes. H pylori infection may affect short-term prognosis in patients with ACS. Randomised trials are needed to evaluate the role of H pylori eradication in these patients.     

Comparison of serum IgA and IgG antibodies for detecting Helicobacter pylori infection

OBJECTIVE: Although the diagnostic utility of serum IgG antibodies to Helicobacter pylori (H. pylori) is well established, the usefulness of IgA-based tests is less well documented. The aim of this study was to evaluate two commercially available ELISAs, both for IgG and IgA. PATIENTS AND METHODS: Rapid urease test and histology analysis were performed in 183 patients. A patient was considered to be H. pylori-positive when either biopsy test was positive, and considered to be noninfected when both tests were negative. Intestinal metaplasia was determined by dye endoscopy with methylene blue. ELISA testing was performed using the EPI HM-CAP IgG and PP-CAP IgA assays and EIAgen IgG and IgA assays. RESULTS: Sensitivity was 94.7, 93.9, 94.8, and 97.0% for HM-CAP IgG, PP-CAP IgA, EIAgen IgG, and EIAgen IgA, respectively. Although sensitivity was excellent for both IgG and IgA antibodies, specificity of both IgA EIAs was low (PP-CAP 72.6%, EIAgen H. pylori IgA 59.2%). Three of 101 H. pylori-infected patients were PP-CAP positive and HM-CAP negative and four were EIAgen H. pylori IgA positive and EIAgen IgG negative. Of eight noninfected patients in whom intestinal metaplasia was found, PP-CAP IgA results were positive in three of five patients with a HM-CAP IgG negative result and EIAgen IgA was detected in one of four patients with an EIAgen IgG negative result. CONCLUSIONS: Since some patients have IgA positive but IgG negative results, great care should be taken not to underestimate the prevalence of H. pylori infection from the results of IgG serology.     

Detection of anti-Helicobacter pylori antibodies in serum and duodenal fluid in peptic gastroduodenal disease

AIM: To study the diagnosis of Helicobacter pylori (H pylori) infection through the determination of serum levels of anti-H pylori IgG and IgA antibodies, and the levels of anti-H pylori IgA antibodies in duodenal fluid. METHODS: Data were collected from 93 patients submitted to upper digestive endoscopy due to dyspeptic symptoms. The patients were either negative (group A) or positive (group B) to H pylori by means of both histological detection and urease tests. Before endoscopy, peripheral blood was collected for the investigation of anti-H pylori IgG and IgA antibodies. To perform the urease test, biopsies were obtained from the gastric antrum. For the histological evaluation, biopsies were collected from the gastric antrum (greater and lesser curvatures) and the gastric body. Following this, duodenal fluid was collected from the first and second portions of the duodenum. For the serological assaying of anti-H pylori IgG and IgA, and anti-H pylori IgA in duodenal fluids, the ELISA method was utilized. RESULTS: The concentration of serum IgG showed sensitivity of 64.0%, specificity of 83.7%, positive predictive value of 82.0%, negative predictive value of 66.6% and accuracy of 73.1% for the diagnosis of H pylori infection. For the same purpose, serum IgA showed sensitivity of 72.0%, specificity of 65.9%, positive predictive value of 72.0%, negative predictive value of 67.4% and accuracy of 69.8%. If the serological tests were considered together, i.e. when both were positive or negative, the accuracy was 80.0%, sensitivity was 86.6%, specificity was 74.2%, positive predictive value was 74.2% and negative predictive value was 86.6%. When values obtained in the test for detecting IgA in the duodenal fluid were analyzed, no significant difference (P = 0.43) was observed between the values obtained from patients with or without H pylori infection. CONCLUSION: The results of serum IgG and IgA tests for H pylori detection when used simultaneously, are more efficient in accuracy, sensitivity and negative predictive value, than those when used alone. The concentration of IgA antibodies in duodenal fluid is not useful in identifying patients with or without H pylori.     

Chlamydial antibodies in an elderly Finnish population.

The characteristic feature of Chlamydia is its tendency to cause chronic infections. It has been hypothesized that prior exposure to C. pneumoniae may lead to chronic infection and the development of associated chronic cardiopulmonary disease. Few studies have so far addressed the occurrence of chlamydial antibodies in an elderly, unselected population. This information is important for the development of possible treatment strategies. Chlamydial antibodies were analysed from 1179 serum samples obtained from 481 men and 698 women, aged 64 y and over, who participated in an epidemiological survey carried out in a Finnish rural district. Specific IgG and IgA antibodies were measured by the microimmunofluorescence (micro-IF) test. The criterion for seropositivity was defined as a titre of > or =32 for both IgG and IgA, independently of each other. C. pneumoniae IgG antibodies occurred in 91% of the men and 75% of the women. The respective figures for C. pneumoniae IgA antibodies were 57% and 28%. The geometric mean titres (GMT) rose with increasing age and were higher in men than in women. The prevalences of C. trachomatis IgG antibodies were 13% in men and 18% in women, and for IgA antibodies, 2% and 1%, respectively. C. psittaci antibodies were rare. Only 3% of the men and women were IgG seropositive, whereas the respective figures for IgA seropositivity were 0.4% and 0.1%. C. pneumoniae antibodies indicative of recurrent or chronic infection were common in the elderly. The geometric mean titres correlated positively with age and were higher in men than in women. Other chlamydial antibodies occurred in low titres.     

Helicobacter pylori-Related gastroduodenal disease in children

To evaluate the accuracy of IgG and IgA serological tests in establishing a diagnosis of Helicobacter (Campylobacter) pylori gastric infection, 60 children presenting with chronic abdominal pain were prospectively studied. Endoscopic antral biopsies were obtained and analyzed for the presence of H. pylori using three standard methods: culture and identification of bacterial isolates, microscopic examination for morphologically characteristic bacteria, and urease production by the biopsy specimen. Concomitantly obtained serum samples were analyzed for the presence of IgG and IgA antibodies against H. pylori surface antigens using enzyme-linked immunosorbent assay (ELISA). Thirty-four of 60 (56.6%) had histological evidence of chronic active gastritis, eight of whom (13.3%) also had evidence of H. pylori infection by at least one criteria. Six of the eight infected patients had H. pylori demonstrated by all three methods. Of the eight infected patients, seven had IgG antibodies against H. pylori (sensitivity of 87%) and six had IgA antibodies (sensitivity of 75%). Among the six patients who had H. pylori infection confirmed by all three methods, all had IgG antibodies (sensitivity of 100%). In the patients without evidence of H. pylori infection, the IgG ELISA had a specificity of 96% (50/52), and the IgA ELISA had a specificity of 100% (52/52). Our data suggest that serological testing for the presence of antibodies against H. pylori may be a useful diagnostic tool in screening children with chronic abdominal pain for the presence of gastric infection with H. pylori.     

Serum anti-Lewis X antibody is associated with VacA seropositivity but not atrophic gastritis in patients with Helicobacter pylori infection

OBJECTIVES: Lipopolysaccharides of Helicobacter pylori have an antigenic structure that mimics Lewis X occurring in gastric mucosa. The pathogenic role of antigenic mimicry in H. pylori-induced gastritis has been of recent interest. The aim of this study was to examine the relevance of anti-Lewis X antibody in the development of atrophic gastritis in H. pylori infection. METHODS: A total of 72 patients were studied. Serum samples were collected to measure IgG antibodies to H. pylori, CagA, VacA and Lewis X. Biopsy specimens were obtained from the antrum and the corpus to examine the grade and the type of atrophic gastritis. RESULTS: Mean anti-Lewis X antibody titres were higher in 38 VacA-seropositive patients than in 13 seronegative patients (P < 0.05). The difference was not significant between patients with diffuse-type atrophic gastritis and those with multi-focal type. No significant correlation was observed between the titre of anti-Lewis X antibody and the grade of glandular atrophy, whereas CagA seropositivity was associated with glandular atrophy. CONCLUSIONS: Anti-Lewis X antibody may play a role in persistent gastric inflammation, particularly in VacA-seropositive H. pylori infection. However, anti-Lewis X antibody does not seem itself to be associated with atrophic gastritis in patients with H. pylori infection.     

Association of Helicobacter pylori IgA antibodies with the risk of peptic ulcer disease and gastric cancer

AIM: To compare the prevalence of Helicobacter pylori (H pylori) IgG and IgA antibodies between adult subjects, with defined gastric diseases, nondefined gastric disorders and those representing the population. METHODS: Data on H pylori IgG and IgA antibodies, determined by enzyme immunoassay, were analyzed in 3 252 subjects with DGD including 482 patients with gastric ulcer, 882 patients with duodenal ulcer, 1 525 patients with chronic gastritis only and 363 subjects with subsequent gastric cancer, 19 145 patients with NoDg and 4 854 POPUL subjects. The age-adjusted prevalences were calculated for 1-and 20-year age cohorts. RESULTS: The prevalences of IgG antibodies were equally high (89-96%) in all 20-year age cohorts of the DGD groups, whereas the prevalences of IgG antibodies were lower and increased by age in the POPUL and NoDg groups. The prevalences of IgA antibodies were also higher in the DGD groups; among them CA (84-89%) and GU groups (78-91%) showed significantly higher prevalences than DU (68-77%) and CG patients (59-74%) (OR 2.49, 95%CI 1.86-3.34 between the GU and DU groups). In the CA, GU, and DU groups, the IgA prevalences showed only minor variation according to age, while they increased by age in the CG, POPUL, and NoDg groups (P≤0.0001). The IgA response, but not the IgG response, was associated with an increased risk of CA (OR 2.41, 95%CI 1.79-3.53) and GU (OR 2.57, 95%CI 1.95-3.39) in comparison with CG patients. CONCLUSION: An IgA antibody response during H pylori infection is significantly more common in CA and GU patients as compared with CG patients.     

Helicobacter pylori infection in interleukin-4-deficient and transgenic mice

BACKGROUND: Interleukin (IL)-4 is a potent anti-inflammatory and Th2-type immunoregulatory cytokine. Helicobacter pylori infection in humans induces a polarized Th1 immune response characterized by increased production of interferon-gamma and absence of IL-4. This study was designed to determine the role of endogenous IL-4 in the host defence against gastric colonization by H. pylori using IL-4-deficient (IL-4-/-) and transgenic (IL-4 Tg) mice. METHODS: IL-4-/- mice and IL-4 Tg mice were inoculated intragastrically with H. pylori Sydney Strain 1. Gastric colonization by H. pylori (biopsy urease test and bacterial colony counts), serum levels of H. pylori-specific immunoglobulin M, A, G, isotypes of IgG, and the gastric mucosal inflammatory scores were determined 6 weeks after inoculation. Results were compared with those obtained from H. pylori-infected IL-4+/+ (controls for IL-4-/- mice) and IL-4 WT (controls for IL-4 Tg) mice. RESULTS: Colonization of the gastric mucosa by H. pylori in IL-4-/- mice was similar to that of control IL-4+/+ mice. There was no significant difference in titres of H. pylori-specific antibodies or gastric inflammatory scores between the two groups of mice. Colonization of gastric mucosa by H. pylori was consistently lower in IL-4 Tg mice (log10 6.40+/-1.09 CFU/g tissue) compared with IL-4WT mice (log10 7.20+/-0.34 CFU/g tissue), although the difference was not significant. Nevertheless, IL-4 Tg mice did have significantly higher titres of H. pylori-specific IgA and IgG (P< or =0.01). CONCLUSION: These results show that endogenous IL-4 is not a major contributor to host resistance to H. pylori, and enhanced IL-4 production has little if any effect on gastric colonization by this organism, despite increased specific antibody production.     

Inbred mice infected with Plasmodium yoelii differ in their antimalarial immunoglobulin isotype response

Antibodies are known to be important in mediating malarial immunity, but the influence of the various immunoglobulin isotypes on parasite elimination is unclear. The purpose of this study was to provide basic information on the induction of isotype expression in genetically different mice during primary malaria. Parasitaemias and the serum antimalarial IgM, IgG1, IgG2, IgG3 and IgA antibody titres measured in a radioimmunoassay were followed in outbred and 11 inbred strains of mice infected with 17XNL Plasmodium yoelii. Severity of infection, as judged by length of infection, peak parasitaemias and death, was found to differ between the strains. All strains developed rapid IgM responses, but only 3/11 inbred strains produced significant antimalarial IgG1 levels during primary infection. All strains produced an IgG2 response, which developed slightly more quickly in strains with the least severe courses of malaria. A large variation in the IgG3 response was noted between strains. In general, IgG3 antibodies were the first IgG-isotype to appear in serum. They were detected as early as day 8 in strains that developed mild infections but were not present until around day 20 in strains with the most severe cases of malaria. Only one strain produced detectable antimalarial IgA antibodies. These results show that different patterns of isotype expression are induced in inbred strains of mice during primary P. yoelii infection.     

Circulating antibodies to cow's milk proteins in ulcerative colitis

Sera from patients with ulcerative colitis (51), Crohn's disease (30), hypolactasia (13), untreated adult coeliac disease (11), irritable colon syndrome (24), and sera from 38 healthy control subjects were tested for antibodies to the principal cow's milk proteins-casein, alpha-lactalbumin, and beta-lactoglobulin. The red-cell-linked antigen-antiglobulin reaction was used to determine the titres of direct agglutinating antibodies and IgA and IgG incomplete antibodies.Apart from patients with coeliac disease, direct agglutinating antibodies were found infrequently and then in low titres. Approximately 50% of subjects had low titres of IgA and IgG antibodies. However, the titres found in sera from patients with ulcerative colitis did not differ from those found in the control subjects or in patients with Crohn's disease, hypolactasia, or irritable colon syndrome. Patients with untreated coeliac disease frequently had high antibody titres to the milk proteins. In all subjects tested, incomplete antibodies of IgA or IgG immunoglobulin class occurred with equal frequency.The frequent occurrence in adults of low titres of antibodies to the milk proteins may be due to continued absorption of minute amounts of protein. Absorption of allergens may be facilitated by mucosal damage, such as that of coeliac disease, with stimulation of antibody production. At the present time, however, there is little evidence to suggest that milk allergy is a factor in the aetiology of ulcerative colitis.     

Performance of Two Immunosorbent Assay Kits for the Detection of Serum Immunoglobulin G to Helicobacter pylori in Untreated Greek Patients

Background: The performance of serological methods used to detect Helicobacter pylori varies with the ethnicity and prevalence of the infection in the community. We have prospectively evaluated the performance of two commercially available serum enzyme immunoassays (EIA) detecting H. pylori immunoglobulin G (IgG) antibodies in the sera of untreated Greek patients. Methods: One-hundred-and-thirty consecutive untreated dyspeptic patients underwent endoscopy with biopsies from the gastric body ( n = 2) and antrum ( n = 2). Serum samples were also obtained from each patient. Serum H. pylori IgG antibody titres were determined with two EIA kits (Pyloriset EIA-G and Milenia H. pylori IgG). Sensitivities, specificities and optimal cut-off values of serum EIAs were determined for the population under investigation by using receiver operating characteristic (ROC) curve analysis and histology as gold standard. Results: Ninety-seven patients were defined H. pylori -positive and 33 negative by histology. ROC curve analysis for the Pyloriset kit yielded 86% (95% CI, 78%-92%) sensitivity and 85% (68%-95%) specificity at an optimal cut-off value of &#83 358 units/ml. The respective values for the Milenia kit were 86% (78%-92%) and 82% (65%-93%) at an optimal cut-off value of &#83 51 units/ml. The suggested cut-off values of the manufacturers for Pyloriset and Milenia kits are &#83 300 and &#83 44 EIA units, respectively, which yield 2% and 4% higher sensitivity, but 9% lower specificity for both EIA kits. Conclusions: Both serum EIA kits performed well in our study. Our data show that EIA cut-off values should be optimized for the population under investigation.     

Evidence of chronic Chlamydia pneumoniae infection in patients with Behçet's disease

Beh?et's disease is a chronic vasculitis of unknown aetiology. Particular viral and bacterial pathogens have long been suspected of playing a role in the pathogenesis of the disease. Chlamydia pneumoniae is an intracellular bacterium capable of causing chronic infections. Some reports have suggested that the microorganism might be involved in the pathogenesis of vasculitis. The purpose of the present study was to investigate a possible correlation between C. pneumoniae infection and Beh?et's disease. For this purpose, 90 consecutive patients with Beh?et's disease and 50 healthy controls were enrolled. Immunoglobulin A (IgA) and IgG antibodies to C. pneumoniae were determined by 2 different techniques, namely indirect fluorescent antibody assay (IFA) and enzyme linked immunosorbent assay (ELISA). IgA antibodies to C. pneumoniae were detected in 17 (18.9%) patients with Beh?et's disease and in 1 (2%) healthy control by IFA. By ELISA 27 patients (30.0%) and 6 controls (12.0%) had C. pneumoniae IgA. A significant difference was observed for IgA seropositivity between the 2 groups. Although IgG seropositivity between the 2 groups did not differ significantly, the number of individuals with IgG titres of > or = 1:1000 was significantly higher in the patient group (43.1%) compared with the control group (13.9%). These finding provide serological evidence of chronic C. pneumoniae infection in association with Beh?et's disease.