Efficient and non-invasive method for investigating Helicobacter pylori in gravida with hyperemesis gravidarum: Helicobacter pylori stool antigen test

Are serum delta neutrophil index and other inflammatory marker levels different in hyperemesis gravidarum?

AIM

Hyperemesis gravidarum (HEG) is a condition characterized by nausea and vomiting, fluid electrolyte and acid-base imbalance, dehydration, weight loss, and ketonuria in early pregnancy. The relationship of HEG with inflammation has been studied in many studies. This study aimed to investigate the role of serum delta neutrophil index (DNI), a new inflammatory marker, and other inflammatory markers in demonstrating the disease's presence and severity in HEG patients.

MATERIAL AND METHOD

This retrospective study was conducted by accessing the electronic data of 79 pregnant women diagnosed with HEG in a tertiary center between 2017 and 2022 and 100 healthy pregnant women. The demographic characteristics of the study and control groups, as well as the hematological parameters in the complete blood count and the levels of inflammatory markers, were recorded.

RESULTS

There was no significant difference between the groups regarding hematological parameters, DNI, platelet-lymphocyte ratio, monocyte-lymphocyte ratio, and systemic inflammation index (p > 0.05). Neutrophil count and neutrophil-lymphocyte ratio (NLR) were higher in the HEG group compared to the control group (p < 0.05).

CONCLUSION

This is the first study to determine the relationship between HEG and serum DNI, a new inflammatory marker. We found that serum DNI values in HEG patients were not different from normal pregnancies and did not reflect the presence and severity of the disease. We also found that inflammatory markers other than the NLR were not different from normal pregnancies in HEG patients.

Emerging Progress in Nausea and Vomiting of Pregnancy and Hyperemesis Gravidarum: Challenges and Opportunities

Nausea and vomiting of pregnancy (NVP) is a common condition that affects up to 70% of pregnant women. Hyperemesis gravidarum (HG) is considered the serious form of NVP, which is reported in 0.3–10.8% of pregnant women. NVP has a relatively benign course, but HG can be linked with some poor maternal, fetal, and offspring outcomes. The exact causes of NVP and HG are unknown, but various factors have been hypothesized to be associated with pathogenesis. With the advance of precision medicine and molecular biology, some genetic factors such as growth/differentiation factor 15 (GDF15) have become therapeutic targets. In our review, we summarize the historical hypotheses of the pathogenesis of NVP and HG including hormonal factors, Helicobacter pylori, gastrointestinal dysmotility, placenta-related factors, psychosocial factors, and new factors identified by genetics. We also highlight some approaches to the management of NVP and HG, including pharmacological treatment, complementary treatment, and some supporting treatments. Looking to the future, progress in understanding NVP and HG may reduce the adverse outcomes and improve the maternal quality of life during pregnancy.

Hyperemesis Gravidarum in First-Trimester Pregnant Saudi Women: Is Helicobacter pylori a Risk Factor?

Introduction

Hyperemesis gravidarum (HG) is a serious complication of pregnancy involving nausea and vomiting which affects all facets of the lives of many women. Helicobacter pylori infection has been linked to HG in some regions of the world. However, the prevalence of H. pylori in Saudi Arabian pregnant women and its link to HG has not been the subject of previous research. Detecting and treating H. pylori infection in women early in their pregnancies may lower the likelihood of adverse maternal outcomes. This study aims to assess the connection between the pathogenesis of HG and H. pylori infection in this population.

Methods

Forty-five pregnant women with HG were recruited from the outpatient clinic for antenatal care in the Gynecology and Obstetrics Department at King Abdulaziz University Hospital. Forty-five pregnant women without HG were matched as controls. Both groups underwent testing for the H. pylori antigen in stool samples.

Results

A statistically significant difference (P < 0.05) was observed between the cases and controls in terms of the occurrence of H. pylori. Thirty-eight women in the HG group (84.4%) tested positive for H. pylori, while the same was true of only 20 of the controls (44.4%). The mean level of blood hemoglobin in positive cases was significantly lower than that in negative cases (9.56 ± 1.29 vs. 11.90 ± 1.18 g/dl, P = 0.012).

Conclusion

H. pylori may play a contributing role in the presence of HG in the study population. It may be included with other investigations of HG, especially with cases that do not respond to conventional management and continue into the second trimester. Women with H. pylori were also more likely to suffer from anemia compared to those without the infection. For this reason, those working with pregnant women should pay close attention to those infected with H. pylori. Additional large case–control studies are necessary to better understand the part H. pylori plays and the pathogenesis of HG.

Predictive factors of Hyperemesis Gravidarum: A systematic review

PURPOSE

Hyperemesis gravidarum (HG) is the main cause of hospitalization during the first trimester of pregnancy. Although it has been associated with serious complications, little is known about its predictive factors. The aim of this systematic review was to search for and critically appraise the studies that investigate the predictive factors for HG.

METHODS

Search strategy included PubMed, CENTRAL and EMBASE databases (till December 2017). All studies examining risk factors for HG were included. Screening of available studies was carried out by two reviewers, as well as the quality assessment of the included studies, based on the Newcastle-Ottawa Scale for observational studies.

RESULTS

The search located 308 articles, of which 14 observational studies (four low-, eight medium- and two high-quality), involving 1400 women who met the eligibility criteria. In four studies, there was no association between Helicobacter (H.) Pylori infection and HG, in contrast to two studies which demonstrated such an association. Pre-pregnancy body mass index (BMI), adipose tissue, maternal age, leptin, ghrelin, beta-chorionic gonadotropin (β-hCG), total (T₄) and free thyroxine (fT₄) correlated with HG in various studies, and could be considered as predictive markers. Regarding the high-quality evidence, a cohort study associated leptin and nephatin-1 with HG, whereas a cross-sectional study found no association between H. pylori infection and HG.

CONCLUSIONS

More studies of high quality and adequate sample size have to be carried out to identify the predictive factors for HG.

Non-invasive diagnostic tests for Helicobacter pylori infection

BACKGROUND

Helicobacter pylori (H pylori) infection has been implicated in a number of malignancies and non-malignant conditions including peptic ulcers, non-ulcer dyspepsia, recurrent peptic ulcer bleeding, unexplained iron deficiency anaemia, idiopathic thrombocytopaenia purpura, and colorectal adenomas. The confirmatory diagnosis of H pylori is by endoscopic biopsy, followed by histopathological examination using haemotoxylin and eosin (H & E) stain or special stains such as Giemsa stain and Warthin-Starry stain. Special stains are more accurate than H & E stain. There is significant uncertainty about the diagnostic accuracy of non-invasive tests for diagnosis of H pylori.

OBJECTIVES

To compare the diagnostic accuracy of urea breath test, serology, and stool antigen test, used alone or in combination, for diagnosis of H pylori infection in symptomatic and asymptomatic people, so that eradication therapy for H pylori can be started.

SEARCH METHODS

We searched MEDLINE, Embase, the Science Citation Index and the National Institute for Health Research Health Technology Assessment Database on 4 March 2016. We screened references in the included studies to identify additional studies. We also conducted citation searches of relevant studies, most recently on 4 December 2016. We did not restrict studies by language or publication status, or whether data were collected prospectively or retrospectively.

SELECTION CRITERIA

We included diagnostic accuracy studies that evaluated at least one of the index tests (urea breath test using isotopes such as 13C or 14C, serology and stool antigen test) against the reference standard (histopathological examination using H & E stain, special stains or immunohistochemical stain) in people suspected of having H pylori infection.

DATA COLLECTION AND ANALYSIS

Two review authors independently screened the references to identify relevant studies and independently extracted data. We assessed the methodological quality of studies using the QUADAS-2 tool. We performed meta-analysis by using the hierarchical summary receiver operating characteristic (HSROC) model to estimate and compare SROC curves. Where appropriate, we used bivariate or univariate logistic regression models to estimate summary sensitivities and specificities.

MAIN RESULTS

We included 101 studies involving 11,003 participants, of which 5839 participants (53.1%) had H pylori infection. The prevalence of H pylori infection in the studies ranged from 15.2% to 94.7%, with a median prevalence of 53.7% (interquartile range 42.0% to 66.5%). Most of the studies (57%) included participants with dyspepsia and 53 studies excluded participants who recently had proton pump inhibitors or antibiotics.There was at least an unclear risk of bias or unclear applicability concern for each study.Of the 101 studies, 15 compared the accuracy of two index tests and two studies compared the accuracy of three index tests. Thirty-four studies (4242 participants) evaluated serology; 29 studies (2988 participants) evaluated stool antigen test; 34 studies (3139 participants) evaluated urea breath test-13C; 21 studies (1810 participants) evaluated urea breath test-14C; and two studies (127 participants) evaluated urea breath test but did not report the isotope used. The thresholds used to define test positivity and the staining techniques used for histopathological examination (reference standard) varied between studies. Due to sparse data for each threshold reported, it was not possible to identify the best threshold for each test.Using data from 99 studies in an indirect test comparison, there was statistical evidence of a difference in diagnostic accuracy between urea breath test-13C, urea breath test-14C, serology and stool antigen test (P = 0.024). The diagnostic odds ratios for urea breath test-13C, urea breath test-14C, serology, and stool antigen test were 153 (95% confidence interval (CI) 73.7 to 316), 105 (95% CI 74.0 to 150), 47.4 (95% CI 25.5 to 88.1) and 45.1 (95% CI 24.2 to 84.1). The sensitivity (95% CI) estimated at a fixed specificity of 0.90 (median from studies across the four tests), was 0.94 (95% CI 0.89 to 0.97) for urea breath test-13C, 0.92 (95% CI 0.89 to 0.94) for urea breath test-14C, 0.84 (95% CI 0.74 to 0.91) for serology, and 0.83 (95% CI 0.73 to 0.90) for stool antigen test. This implies that on average, given a specificity of 0.90 and prevalence of 53.7% (median specificity and prevalence in the studies), out of 1000 people tested for H pylori infection, there will be 46 false positives (people without H pylori infection who will be diagnosed as having H pylori infection). In this hypothetical cohort, urea breath test-13C, urea breath test-14C, serology, and stool antigen test will give 30 (95% CI 15 to 58), 42 (95% CI 30 to 58), 86 (95% CI 50 to 140), and 89 (95% CI 52 to 146) false negatives respectively (people with H pylori infection for whom the diagnosis of H pylori will be missed).Direct comparisons were based on few head-to-head studies. The ratios of diagnostic odds ratios (DORs) were 0.68 (95% CI 0.12 to 3.70; P = 0.56) for urea breath test-13C versus serology (seven studies), and 0.88 (95% CI 0.14 to 5.56; P = 0.84) for urea breath test-13C versus stool antigen test (seven studies). The 95% CIs of these estimates overlap with those of the ratios of DORs from the indirect comparison. Data were limited or unavailable for meta-analysis of other direct comparisons.

AUTHORS' CONCLUSIONS

In people without a history of gastrectomy and those who have not recently had antibiotics or proton ,pump inhibitors, urea breath tests had high diagnostic accuracy while serology and stool antigen tests were less accurate for diagnosis of Helicobacter pylori infection.This is based on an indirect test comparison (with potential for bias due to confounding), as evidence from direct comparisons was limited or unavailable. The thresholds used for these tests were highly variable and we were unable to identify specific thresholds that might be useful in clinical practice.We need further comparative studies of high methodological quality to obtain more reliable evidence of relative accuracy between the tests. Such studies should be conducted prospectively in a representative spectrum of participants and clearly reported to ensure low risk of bias. Most importantly, studies should prespecify and clearly report thresholds used, and should avoid inappropriate exclusions.

A meta-analysis of the association between Helicobacter pylori (H. pylori) infection and hyperemesis gravidarum

BACKGROUND

Hyperemesis gravidarum remains a common, distressing, and significant yet poorly understood disorder during pregnancy. The association between maternal Helicobacter pylori (H. pylori) infection and hyperemesis gravidarum has been increasingly recognized and investigated. This study thus aimed to provide an updated review and meta-analysis of the topic.

METHODS

Using the search terms (H. pyloriOR Helicobacter ORHelicobacter pyloriOR infection) AND (pregnancy OR emesis OR hyperemesis gravidarum OR nausea OR vomiting), a preliminary search on the PubMed, Ovid, Web of Science, Google Scholar, and WanFang database yielded 372 papers published in English between January 1st, 1960 and June 1st, 2017.

RESULTS

A total of 38 cross-sectional and case-control studies, with a total of 10 289 patients were eligible for review. Meta-analysis revealed a significant association between H. pylori infection and hyperemesis gravidarum during pregnancy, with a pooled odds ratio of 1.348 (95% CI: 1.156-1.539, P < .001). Subgroup analysis found that serologic and stool antigen tests were comparable methods of detecting H. pylori as they yielded similar odds ratios.

LIMITATIONS

Although the studies did not have high heterogeneity (I²  = 28%), publication bias was observed, and interstudy discrepancies in the diagnostic criteria adopted for hyperemesis gravidarum limit the reliability of findings. Also, 15 of the included studies were from the same country (Turkey), which could limit the generalizability of current findings. The prevalence of H. pylori infection varies throughout the world, and there may also be pathogenic differences as most strains of H. pylori in East Asia carry the cytotoxin-associated gene A gene.

CONCLUSION

H. pylori infection was associated with an increased likelihood of hyperemesis gravidarum during pregnancy. Given the high prevalence of H. pylori infections worldwide, detecting H. pylori infection and the eradication of maternal H. pylori infection could be part of maternal hyperemesis gravidarum management. Further confirmation with robust longitudinal studies and mechanistic investigations are needed.

The Management of Nausea and Vomiting of Pregnancy

OBJECTIVES

To review the evidence-based management of nausea and vomiting of pregnancy and hyperemesis gravidarum.

EVIDENCE

MEDLINE and Cochrane database searches were performed using the medical subject headings of treatment, nausea, vomiting, pregnancy, and hyperemesis gravidarum. The quality of evidence reported in these guidelines has been described using the Evaluation of Evidence criteria outlined in the Report of the Canadian Task Force on Preventative Health Care.

BENEFITS

Nausea and vomiting of pregnancy has a profound effect on women's health and quality of life during pregnancy as well as a financial impact on the health care system, and its early recognition and management is recommended. COST: Costs, including hospitalizations, additional office visits, and time lost from work, may be reduced if nausea and vomiting in pregnancy is treated early.

RECOMMENDATIONS

Dynamic thiol-disulfide homeostasis in hyperemesis gravidarum

OBJECTIVE

To determine serum thiol-disulfide homeostasis in hyperemesis gravidarum.

STUDY DESIGN

Twenty-six pregnant women with hyperemesis gravidarum and 37 healthy pregnant women were included in the study. Native thiol, disulfide and total thiol concentrations were measured with a novel automated method.

RESULTS

Serum disulfide levels were 15.68±4.41 μmol l(-1) in the hyperemesis gravidarum group and 13.49±2.81 μmol l(-1) in the healthy group (P=0.031). Native thiol levels were 213.86±26.29 μmol l(-1) in the hyperemesis gravidarum group and 232.18±19.21 μmol l(-1) in healthy group (P=0.004), and total thiol levels were 245.23±28.58 μmol l(-1) in the hyperemesis gravidarum group and 259.17±19.94 μmol l(-1) in the healthy group (P=0.038).

CONCLUSION

Native and total thiol were deficient in the hyperemesis gravidarum group and this deficiency was correlated with the severity of the disease. The thiol-disulfide balance has shifted to the oxidative side. This metabolic disturbance may have a role in the pathogenesis of hyperemesis gravidarum.

Helicobacter pylori Infection Is Associated with an Increased Risk of Hyperemesis Gravidarum: A Meta-Analysis

Background. Several studies have shown a possible involvement of Helicobacter pylori (H. pylori) infection in individuals with hyperemesis gravidarum (HG), but the relationship remains controversial. This meta-analysis was performed to validate and strengthen the association between HG and H. pylori infection. Methods. PubMed, Embase, and Web of Science databases up to March 20, 2014, were searched to select studies on the prevalence of H. pylori infection between pregnant women with HG and the normal pregnant control subjects. Results. Of the HG cases, 1289 (69.6%) were H. pylori-positive; however, 1045 (46.2%) were H. pylori-positive in control group. Compared to the non-HG normal pregnant controls, infection rate of H. pylori was significantly higher in pregnant women with HG (OR = 3.34, 95% CI: 2.32–4.81, P < 0.001). Subgroup analysis indicated that H. pylori infection was a risk factor of HG in Asia, Africa, and Oceania, especially in Africa (OR = 12.38, 95% CI: 7.12–21.54, P < 0.001). Conclusions. H. pylori should be considered one of the risk factors of HG, especially in the developing countries. H. pylori eradication could be considered to relieve the symptoms of HG in some intractable cases.

The utilization of a new immunochromatographic test in detection of Helicobacter pylori antibody from maternal and umbilical cord serum

Background. Helicobacter pylori (H. pylori) was linked with several extragastrointestinal diseases, including preeclampsia and intrauterine growth restriction of fetus. One of the signals which can be transferred from mother to fetus is the H. pylori IgG antibody. Aims. We utilized a commercial immunochromatographic kit to detect the antibody in maternal and cord serum. Methods. Three hundred and forty-six females were enrolled and the blood samples were collected on antenatal examination and on delivery. The maternal H. pylori infection was determined by stool H. pylori antigen test. Results. One hundred and five females (30.3%) were H. pylori-infected, and the prevalence was higher in immigrants (43.5%) than in Taiwanese (28.7%, P = 0.058). The sensitivity, specificity, positive predictive value, negative predictive value, and accuracy of the kit were 77.1%, 88.0%, 73.6%, 89.8%, and 84.7%, respectively. This kit also had similar performance in cord serum. Comparing to the maternal result on delivery, this kit offered a consistent performance in antenatal maternal serum (kappa coefficient 0.92) and in cord serum (kappa coefficient 0.88). Conclusions. H. pylori IgG antibody can be transferred through the placenta into the fetal circulation. However, accuracy of the test kit needs to be evaluated before utilization in screening.

Diagnostic markers for hyperemesis gravidarum: a systematic review and metaanalysis

OBJECTIVE

Currently, there is no consensus on the definition of hyperemesis gravidarum (HG; protracted vomiting in pregnancy) and no single widely used set of diagnostic criteria for HG. The various definitions rely on symptoms, sometimes in combination with laboratory tests. Through a systematic review, we aimed to summarize available evidence on the diagnostic value of biomarkers for HG. This could assist diagnosis and may shed light on the, as yet, not understood cause of the disorder.

STUDY DESIGN

We searched Medline and Embase for articles about diagnostic biomarkers for either the presence or severity of HG or nausea and vomiting of pregnancy. We defined HG as any combination of nausea, vomiting, dehydration, weight loss, or hospitalization for nausea and/or vomiting in pregnancy, in the absence of any other obvious cause for these complaints.

RESULTS

We found 81 articles on 9 biomarkers. Although 65% of all studies included only HG cases with ketonuria, we did not find an association between ketonuria and presence or severity of HG in 5 studies reporting on this association. Metaanalysis, with the use of the hierarchical summary receiver operating characteristics model, yielded an odds ratio of 3.2 (95% confidence interval, 2.0-5.1) of Heliobacter pylori for HG, as compared with asymptomatic control subjects (sensitivity, 73%; specificity, 55%). Studies on human chorionic gonadotropin and thyroid hormones, leptin, estradiol, progesterone, and white blood count showed inconsistent associations with HG; lymphocytes tended to be higher in women with HG.

CONCLUSION

We did not find support for the use of ketonuria in the diagnosis of HG. H pylori serology might be useful in specific patients.

Helicobacter pylori and pregnancy-related disorders

Helicobacter pylori (H. pylori) infection is investigated in gastric diseases even during pregnancy. In particular, this Gram-negative bacterium seems to be associated with hyperemesis gravidarum, a severe form of nausea and vomiting during pregnancy. During the last decade, the relationship among H. pylori and several extra-gastric diseases strongly emerged in literature. The correlation among H. pylori infection and pregnancy-related disorders was mainly focused on iron deficiency anemia, thrombocytopenia, fetal malformations, miscarriage, pre-eclampsia and fetal growth restriction. H. pylori infection may have a role in the pathogenesis of various pregnancy-related disorders through different mechanisms: depletion of micronutrients (iron and vitamin B₁₂) in maternal anemia and fetal neural tube defects; local or systemic induction of pro-inflammatory cytokines release and oxidative stress in gastrointestinal disorders and pre-eclampsia; cross-reaction between specific anti-H. pylori antibodies and antigens localized in placental tissue and endothelial cells (pre-eclampsia, fetal growth restriction, miscarriage). Since H. pylori infection is most likely acquired before pregnancy, it is widely believed that hormonal and immunological changes occurring during pregnancy could activate latent H. pylori with a negative impact not only on maternal health (nutritional deficiency, organ injury, death), but also on the fetus (insufficient growth, malformation, death) and sometime consequences can be observed later in life. Another important issue addressed by investigators was to determine whether it is possible to transmit H. pylori infection from mother to child and whether maternal anti-H. pylori antibodies could prevent infant’s infection. Studies on novel diagnostic and therapeutic methods for H. pylori are no less important, since these are particularly sensitive topics in pregnancy conditions. It could be interesting to study the possible correlation between H. pylori infection and other pregnancy-related diseases of unknown etiology, such as gestational diabetes mellitus, obstetric cholestasis and spontaneous preterm delivery. Since H. pylori infection is treatable, the demonstration of its causative role in pregnancy-related disorders will have important social-economic implications.

Serologic and stool antigen assay of Helicobacter pylori infection in hyperemesis gravidarum: which test is useful during early pregnancy?

OBJECTIVE

To investigate the relationship between Helicobacter pylori infection and hyperemesis gravidarum (HG) during early pregnancy by using serologic and stool antigen tests in developing South Anatolia region of Turkey.

MATERIALS AND METHODS

A prospective cross-sectional study was performed on 40 pregnant women with HG and 40 asymptomatic controls without gastric problems at 7-12 weeks of gestation. The sociodemographic characteristics were recorded. The presence of H pylori was analyzed in the sera of the study-group patients by serology-specific IgG test in serum and by a stool antigen test in fecal samples.

RESULTS

The rates of serology-specific H pylori IgG positivity were 80% (32 of 40) in patients with HG and 35% (14 of 40) in control group. The difference between the two groups was significant [odds ratio: 6.9 (confidence interval: 2.2-22.1); p<0.01]. The rates of H pylori stool antigen test positivity were 87.5% (35 of 40) in patients with HG and 62.5% (25 of 40) in control groups. The difference between the two groups was significant (odds ratio: 4.5, confidence interval: 1.09-18.5); p=0.028.

CONCLUSION

Both serology-specific IgG and stool antigen tests seem to be good screening methods to identify H pylori in our pregnant patient population with HG during early pregnancy.

The positivity of Helicobacter pylori Stool Antigen in patients with Hyperemesis gravidarum

OBJECTIVE

We aimed to investigate the possible association between Helicobacter pylori infection and Hyperemesis gravidarum.

MATERIAL AND METHODS

Thirty-six pregnant women with Hyperemesis gravidarum with severe vomiting (more than 4 times a day), weight loss (≥3 kg), ketonuria and 36 pregnant women gestational age-matched, without nausea and vomiting attending our outpatient clinic for antenatal care were enrolled the study. Demographic data of the patients were registered. Blood samples for hemogram, serum electrolytes (sodium, potassium, chloride, and calcium), alanine aminotransferase (ALT), aspartate aminotransferase (AST), blood urea nitrogen (BUN), creatine, thyroid stimulating hormone (TSH), free T3-T4, total T3-T4, and urine samples for ketonuria, stool samples for HpSA were studied. The data of both groups were compared.

RESULTS

Eight Hyperemesis gravidarum patients (22.2%) and 1 control patient (2.8%) were established HpSA positive and it was statistically significant (p:0.037). There was no significant difference between Hyperemesis gravidarum and control subjects in terms of age, gestational week, parity, educational level, socioeconomic status and smoking. There was anemia in 5 Hyperemesis gravidarum patients, 4 of them were HpSA positive. HpSA positivity was more prevalent in Hyperemesis gravidarum patients with anemia (p=0.003). Severe vomiting (more than 4 times a day), heartburn, epigastric pain, duration of hospitalization (more than 4 days) and weight loss (≥5 kg) were not correlated to HpSA positivity.

CONCLUSION

The pregnant women with Hyperemesis gravidarum have a significantly higher prevalence of Helicobacter pylori compared with control subjects.

Hyperemesis gravidarum and Helicobacter pylori infection: a systematic review

OBJECTIVE

To systematically review studies examining the relationship between hyperemesis gravidarum and Helicobacter pylori (H pylori) infection.

DATA SOURCES

A 1966 to January 2007 search using MEDLINE/PubMed, EMBASE, and Web of Science included MeSH terms: "Helicobacter pylori," "Helicobacter infections," "hyperemesis gravidarum," and the text words "nausea," "vomit," "pregnancy," and "Helicobacter." References of selected papers were examined for additional relevant studies.

METHODS OF STUDY SELECTION

We evaluated studies investigating a relationship between hyperemesis gravidarum and H pylori infection. Studies were included in which the diagnosis of hyperemesis gravidarum was made at or before entry into the study, and H pylori diagnosis was made by serum antibody sample, gastric biopsy, saliva test, or stool sample. The search produced 169 titles; 22 were reviewed in further detail.

TABULATION, INTEGRATION, AND RESULTS

Fourteen case-control studies met established criteria, involving 1,732 participants and controls tested for H pylori infection. Studies were evaluated according to patient demographics and study methodology (case definition, exclusion criteria, H pylori testing). An estimate of the odds ratios with 95% confidence intervals was calculated by using a random effects model for dichotomous variables with review article software. Ten studies showed a significant association between hyperemesis gravidarum and H pylori infection. Odds ratios varied from 0.55 to 109.33; three results were less than 1.0. Tests for heterogeneity applied to several subgroups were considerable with values above 75% for all groups.

CONCLUSION

An association between hyperemesis gravidarum and H pylori infection is suggested by this systematic review. However, the considerable heterogeneity among studies highlights study limitations.

Helicobacter pylori stool antigen assay in hyperemesis gravidarum: a risk factor for hyperemesis gravidarum or not?

OBJECTIVE

To test the hypothesis that Helicobacter pylori (H. pylori) infection may cause hyperemesis gravidarum (HG).

MATERIALS AND METHODS

A prospective-comparative study was performed on 107 pregnant patients from October 2002 to December 2003 in a university-based prenatal care clinic. Blood and stool samples were obtained from 52 patients diagnosed as HG and 55 matched asymptomatic pregnant women. H. pylori stool antigen (HpSA) status of the participants was evaluated using a commercially available enzyme immunoassay-based kit.

RESULTS

The overall prevalence of HpSA positivity appeared as 41.1%. Twenty-two of 52 (42.3%) HG patients and 22 of 55 (40.0%) control subjects were positive for HpSA. The difference was not significant (p>.05).

CONCLUSION

HG seemed to be not associated with H. pylori infection, as indicated by specific stool antigen assay.

Detection rate of Helicobacter pylori stool antigen in newborn infants and small children

AIMS

To investigate the prevalence of H. pylori antigen in the stools of Norwegian neonates and small children.

METHODS

A total of 249 children aged 0 days-3 years were tested for the presence of H. pylori antigen in feces using the HpSA immunoassay. For verification purposes, a selection of samples were analyzed with PCR targeting the 16 S rDNA Helicobacter gene.

RESULTS

H. pylori antigen in stool was detected in 52% (36/69) of the neonates, in 15% (7/46) of infants aged 7 days-1 month, and in 5% (7/134) of children aged 1 month-3 years. In neonates, H. pylori antigen detection was significantly associated with mode of delivery: 59% (30/51) with uncomplicated vaginal births were HpSA positive compared to only 10% (1/10) of infants delivered by cesarean section (P=0.02). Positive PCR results were found in 35% (9/26) of HpSA positive samples. Sequencing of PCR products revealed 97-100% homology with gene sequences from both H. pylori and other Helicobacter species.

CONCLUSIONS

The low H. pylori antigen detection rate in children >1 month of age is in accordance with previous prevalence studies from Western countries. The unexpected finding of a high H. pylori antigen detection rate in neonates suggests that transient colonization may occur in the neonatal period.

The prevalence of Helicobacter pylori in the Hispanic population affected by hyperemesis gravidarum

OBJECTIVE

The purpose of this study was to determine the prevalence of Helicobacter pylori seropositivity in pregnant Hispanics affected by hyperemesis gravidarum.

STUDY DESIGN

This was a prospective cross-sectional study conducted over a 22-month period. Serum from pregnant Hispanics affected by hyperemesis gravidarum and unaffected Hispanics matched for age, gravidity, parity, and country of origin were tested for H pylori immunoglobulin G (IgG). IgG levels specific for H pylori were determined by enzyme-linked immunosorbent assay (ELISA). Assuming the background prevalence of H pylori serum positivity in the Hispanic population is approximately 60%, 38 patients in each group were needed to detect a 30% difference in affected patients versus controls with a power of 80% and P = .05. Statistical analysis was performed using Yate's chi-square, Student t test, Mann-Whitney U, and binary logistic regression.

RESULTS

A total of 82 patients between the ages of 18 to 39 years were enrolled. Of 40 patients diagnosed with hyperemesis gravidarum, 26 (65%) were seropositive for H pylori compared with 28 of 42 (67%) unaffected controls (P = 1.0). There were no statistical differences in maternal age or countries of origin between the 2 groups.

CONCLUSION

The overall prevalence of H pylori seropositivity in this patient population is 66%. In pregnant Hispanics affected by hyperemesis gravidarum, H pylori seropositivity is not increased compared with unaffected controls.

Hyperemesis gravidarum, a literature review

Hyperemesis gravidarum (HG) is a condition causing severe nausea and vomiting in early pregnancy often resulting in hospital admission. The incidence of HG is approximately 0.5% of live births, said to be higher in multiple pregnancies, hydatidiform mole and other conditions associated with increased pregnancy hormone levels. Both the aetiology and pathogenesis of HG remain unknown. We conducted a literature review (1966-now) to summarize the current evidence on the aetiology and pathogenesis of HG. The potential role of pregnancy-related hormones such as progesterone, estrogen and HCG has been widely studied; however, various other hormones such as leptin, placental growth hormone, prolactin, thyroid and adrenal cortical hormones have been implicated in the aetiology of HG. In addition to endocrinological hypotheses, the rationale and evidence considering infectious, immunological, psychological, metabolic and anatomical causes for HG have been analysed here. Many studies suffer from the low number of patients included, the variable definition used for HG and varying assay methodology used in studies of hormone measurement. This review highlights the need for more extensive studies addressing the pathogenesis and aetiology of HG.