Prevalence of Helicobacter pylori Infection and Identification of Risk Factors in Rural and Urban Beijing, China

Background:  The prevalence of Helicobacter pylori is higher in developing countries such as China. The aim of this study was to investigate the prevalence of H. pylori in one rural and one urban region of Beijing, China.
Materials and Methods:  Healthy individuals in rural Pinggu and urban Haidian voluntarily participated in this study. The diagnosis of H. pylori infection was reached using the ¹³C-urea breath test. Associations between H. pylori and sex, age, living area (i.e. rural vs urban), education level, smoking, and alcohol consumption were evaluated.
Results:  Of the 1232 included subjects, 54.7% of tested individuals residing in Pinggu and 41.3% in Haidian were positive for H. pylori . In urban region, more individuals were negative for H. pylori (429 of 731), whereas in the rural region, more individuals were positive for H. pylori ( p <  .05). Univariate analysis identified geographic area and lower education and annual income as significant factors associated with H. pylori . Men in rural areas were more likely than women in rural areas to be infected, and both men and women in the rural area were more likely to be positive for H. pylori than men and women in the urban area (all p  < .05).
Conclusions:  H. pylori infection is common in both rural and urban regions of Beijing. Residing in a rural area, having a lower family income, and lower education level are significant risk factors associated with infection.     

Helicobacter pylori in familial clusters based on antibody profile

Studies have shown a high prevalence of Helicobacter pylori infection in close communities and that intrafamilial spread during early childhood may be a route of transmission. A total of 72 household members from 21 families were enrolled in this study. Sera from individuals showed 50/72 (69.4%) seropositive for IgG against H. pylori by ELISA. Western blots showed diversity in the protein profiles with molecular masses ranging from approximately 8 to 130 kDa. Cohen's kappa statistical analysis of the blot patterns showed that nine families demonstrated similar profiles (100%), while 4 other families showed varying similarities (17-50%). The results support the hypothesis of intrafamilial transmission of H. pylori. Furthermore, serological studies can be used as an effective approach to determine the familial status in relation to H. pylori infection.     

Helicobacter pylori genotyping from American indigenous groups shows novel Amerindian vacA and cagA alleles and Asian, African and European admixture

It is valuable to extend genotyping studies of Helicobacter pylori to strains from indigenous communities across the world to better define adaption, evolution, and associated diseases. We aimed to genetically characterize both human individuals and their infecting H. pylori from indigenous communities of Mexico, and to compare them with those from other human groups. We studied individuals from three indigenous groups, Tarahumaras from the North, Huichols from the West and Nahuas from the center of Mexico. Volunteers were sampled at their community site, DNA was isolated from white blood cells and mtDNA, Y-chromosome, and STR alleles were studied. H. pylori was cultured from gastric juice, and DNA extracted for genotyping of virulence and housekeeping genes. We found Amerindian mtDNA haplogroups (A, B, C, and D), Y-chromosome DYS19T, and Amerindian STRs alleles frequent in the three groups, confirming Amerindian ancestry in these Mexican groups. Concerning H.pylori cagA phylogenetic analyses, although most isolates were of the Western type, a new Amerindian cluster neither Western nor Asian, was formed by some indigenous Mexican, Colombian, Peruvian and Venezuelan isolates. Similarly, vacA phylogenetic analyses showed the existence of a novel Amerindian type in isolates from Alaska, Mexico and Colombia. With hspA strains from Mexico and other American groups clustered within the three major groups, Asian, African or European. Genotyping of housekeeping genes confirmed that Mexican strains formed a novel Asian-related Amerindian group together with strains from remote Amazon Aborigines. This study shows that Mexican indigenous people with Amerindian markers are colonized with H. pylori showing admixture of Asian, European and African strains in genes known to interact with the gastric mucosa. We present evidence of novel Amerindian cagA and vacA alleles in indigenous groups of North and South America.     

Epidemiology of Helicobacter pylori Infection

This review summarizes studies on the epidemiology of Helicobacter pylori published in peer-reviewed journals between April 2007 and March 2008. Infection with H. pylori often occurs in childhood, and once established, can persist lifelong if untreated. Prevalence of H. pylori infection is higher in developing countries when compared to developed countries, and can vary by ethnicity, place of birth, and socioeconomic factors even among persons living in the same country. Prevalence of infection is decreasing in many countries due to improvements in sanitation and living standards and the relatively recent movement of populations from rural to urban settings; however, post-treatment recurrence rates of H. pylori infection remain high in developing countries, and in given populations within developed countries. In addition, a number of recent studies have begun to explore the possible link between childhood infection with H. pylori and protection against asthma and allergy.     

Epidemiology of Helicobacter pylori infection and public health implications

This review summarizes studies on the epidemiology and public health implications of Helicobacter pylori published in peer-reviewed journals from April 2010 through March 2011. Prevalence rates vary widely between different geographical regions and ethnic groups. An interesting study from the USA identified the degree of African ancestry as an independent predictor of H. pylori infection. Two studies have demonstrated early childhood as the period of transmission of infection and identified an infected sibling as an important risk factor. An oral-oral route of spread has been substantiated with several studies showing the presence of H. pylori in the oral cavity. Studies have shown the presence of H. pylori in drinking water and the role of poor living conditions and sanitation in H. pylori infection, supporting an oral-fecal route of spread. Screening for H. pylori as a gastric cancer pre-screening strategy has been described in Japan, and the importance of H. pylori eradication as a gastric cancer-prevention strategy has now been further emphasized in Japanese guidelines. Two studies have shown a decrease in the burden of dyspepsia and peptic ulcer disease with H. pylori eradication.     

The relationship of Helicobacter pylori positivity with age, sex, and ABO/Rhesus blood groups in patients with gastrointestinal complaints in Turkey

BACKGROUND: To determine the magnitude of Helicobacter pylori infection in patients with gastrointestinal complaints in Turkey. METHODS: We studied 1680 patients with variable gastrointestinal complaints. The H. pylori infection status was determined using C-14 urea breath test (UBT). Overall, 1567 patients (548 male, 1019 female; age range 4-80 years, mean 29.37 +/- 17.30 years) were included in this study. The relationship between H. pylori positivity and age, sex, sociodemographic characteristic, blood groups, and gastrointestinal diagnosis was determined. RESULTS: H. pylori positivity was found to be 68%. The difference in positivity rates between age groups 4-9 years and other groups was statistically significant (p = .001). H. pylori positivity was 67.7% in males and 68.2% in females (p = .865). H. pylori positivity was 72.1, 65.1, 70, and 68.4% in blood groups A, B, AB, and O (p = .703), and 68.9% and 76.3% in Rh (+) and Rh (-) blood subgroups, respectively (p = .292). There was no statistically significant difference between H. pylori positivity and gastrointestinal diagnosis (p = .980). There was significant association between increased number of household members and low socioeconomic status, and H. pylori positivity (p < .001). Living in rural and suburban area was significantly associated with H. pylori positivity compared with living in urban. CONCLUSIONS: H. pylori infection positivity rate was 68% in symptomatic subjects in Turkey and the positivity rate was significantly lower at age 4-9 years than the other age groups. It was not related to gender, ABO, and Rh blood groups and gastrointestinal diagnosis. Low socioeconomic conditions and living in rural and suburban area were significantly associated with H. pylori positivity.     

Childhood Hygienic Practice and Family Education Status Determine the Prevalence of Helicobacter pylori Infection in Iran

Background: Management of Helicobacter pylori , a causative agent of gastrointestinal diseases is an important health problem in most countries. The main reasons include poorly defined epidemiological status and unrecognized mode of bacterial transmission. Our objective was to investigate the prevalence of H. pylori infection in a representative population of Iran and to evaluate possible risk factors for the H. pylori infection.
Materials and methods: In this cross-sectional study, 2561 healthy individuals aged 18–65 years (mean age, 35.5 years) were selected out of 12,100,000 inhabitants of Tehran province by cluster sampling. Infection with H. pylori was evaluated by detection of anti- H. pylori IgG antibody in serum. Sociodemographic status of each subject was determined by filling up a questionnaire.
Results: Prevalence of H. pylori infection was 69% and was correlated with increasing age. The highest infection rate (79.2%) was seen in individuals 46–55 years old. No association was detected between H. pylori positivity and gender. Low education of the study subjects; low father's and mother's education; poor tooth brushing habit; crowded families in childhood; and lack of household bath, hygienic drinking water, and swage disposal facility in childhood were determined as possible risk factors.
Conclusions: The rate of prevalence of H. pylori infection was higher than developed countries. Low socioeconomic status, poor sanitary indications, and crowded families in childhood were related to high prevalence of H. pylori infection in Iran. Accordingly, fecal–oral and oral–oral routes could be considered as the main pathways of transmission of H. pylori .     

Three novel mtDNA restriction site polymorphisms allow exploration of population affinities of African Americans

To develop informative tools for the study of population affinities in African Americans, we sequenced the hypervariable segments I and II (HVS I and HVS II) of mitochondrial DNA (mtDNA) from 96 Sierra Leoneans; European Americans; rural, Gullah-speaking African Americans; urban African Americans living in Charleston, South Carolina; and Jamaicans. We identified single nucleotide polymorphisms (SNPs) exhibiting ethnic affinities, and developed restriction endonuclease tools to screen these SNPs. Here we show that three HVS restriction site polymorphisms (RSPs), EcoRV, FokI, and MfeI, exhibit appreciable differences in frequency (average delta = 0.4165) between putative African American parental populations (i.e., extant Africans living in Sierra Leone and European Americans). Estimates of European American mtDNA admixture, calculated from haplotypes composed of these three novel RSPs, show a cline of increasing admixture from Gullah-speaking African American (m = 0.0300) to urban Charleston African American (m = 0.0689) to West Coast African American (m = 0.1769) populations. This haplotype admixture in the Gullahs is the lowest recorded to date among African Americans, consistent with previous studies using autosomal markers. These RSPs may become valuable new tools in the study of ancestral affinities and admixture dynamics of African Americans.     

In silico evolutionary analysis of Helicobacter pylori outer membrane phospholipase A (OMPLA)

ABSTRACT: BACKGROUND: In the past decade, researchers have proposed that the pldA gene for outer membrane phospholipase A (OMPLA) is important for bacterial colonization of the human gastric ventricle. Several conserved Helicobacter pylori genes have distinct genotypes in different parts of the world, biogeographic patterns that can be analyzed through phylogenetic trees. The current study will shed light on the importance of the pldA gene in H. pylori. In silico sequence analysis will be used to investigate whether the bacteria are in the process of preserving, optimizing, or rejecting the pldA gene. The pldA gene will be phylogenetically compared to other housekeeping (HK) gene, and a possible origin via horizontal gene transfer (HGT) will be evaluated through both at intra- and inter-species evolutionary analyses. RESULTS: In this study, pldA gene sequences were phylogenetically analyzed and compared with a large reference set of concatenated HK gene sequences. A total of 246 pldA nucleotide sequences were used; 207 were from Norwegian isolates, 20 were from Korean isolates, and 19 were from the NCBI database. Best-fit evolutionary models were determined with MEGA5 ModelTest for the pldA (K80 + I + G) and HK (GTR + I + G) sequences, and maximum likelihood trees were constructed. Both HK and pldA genes showed biogeographic clustering. Horizontal gene transfer was inferred based on significantly different GC contents, the codon adaptation index, and a phylogenetic conflict between a tree of OMPLA protein sequences representing 171 species and a tree of the AtpA HK protein for 169 species. Although a vast majority of the residues in OMPLA were predicted to be under purifying selection, sites undergoing positive selection were also found. CONCLUSIONS: Our findings indicate that the pldA gene could have been more recently acquired than seven of the HK genes found in H. pylori. However, the common biogeographic patterns of both the HK and pldA sequences indicated that the transfer occurred long ago. Our results indicate that the bacterium is preserving the function of OMPLA, although some sites are still being evolutionarily optimized.     

Differentiation between isolates of Helicobacter pylori by PCR-RFLP analysis of urease A and B genes and comparison with ribosomal RNA gene patterns

Abstract Genetic diversity amongst 21 human gastric isolates of Helicobacter pylori was investigated by polymerase chain reaction amplification and Hae III digest (restriction fragment length polymorphism) analysis of an internal 2.4-kb segment of the urease A and urease B genes. H. pylori from 11 independent individuals yielded nine distinct restriction fragment patterns but only one pattern was common to H. pylori from two individuals. By contrast, multiple isolate sets of H. pylori from two patients each had common urease gene patterns. Most strains with the same urease gene patterns were distinguishable in their ribosomal RNA gene patterns. The study demonstrated diversity amongst H. pylori and established that PCR analysis of urease genes provided a novel method of identifying isolates. The profiles were reproducible and convenient to obtain and analyse, and were almost as discriminatory as Hae III ribopatterns.     

Insights into Nasal Carriage of Staphylococcus aureus in an Urban and a Rural Community in Ghana

The epidemiology of Staphylococcus aureus in the community in Ghana was never investigated prior to this study. The aims of the study were: i) to assess prevalence of nasal S. aureus carriage in Ghanaian people living in an urban and a rural area, and ii) to identify phenotypic and genotypic traits of strains isolated from the two communities. Nasal swabs were collected from healthy individuals living in an urban community situated in the suburb of the capital city, Accra (n = 353) and in a rural community situated in the Dangme-West district (n = 234). The overall prevalence of nasal carriage was 21% with a significantly higher prevalence in the urban (28%) than in the rural community (11%) (p<0.0001). The levels of antimicrobial resistance were generally low (<5%) except for penicillin (91%) and tetracycline (25%). The only two (0.3%) MRSA carriers were individuals living in the urban area and had been exposed to hospitals within the last 12 months prior to sampling. Resistance to tetracycline (p = 0.0009) and presence of Panton-Valentine leukocidin (PVL) gene (p = 0.02) were significantly higher among isolates from the rural community compared to isolates from the urban community. Eleven MLST clonal complexes (CC) were detected based on spa typing of the 124 S. aureus isolates from the two communities: CC8 (n = 36), CC152 (n = 21), CC45 (n = 21), CC15 (n = 18), CC121 (n = 6), CC97 (n = 6), CC30 (n = 5), CC5 (n = 5), CC508 (n = 4), CC9 (n = 1), and CC707 (n = 1). CC8 and CC45 were less frequent in the rural area than in the urban area (p = 0.02). These results reveal remarkable differences regarding carriage prevalence, tetracycline resistance, PVL content and clonal distribution of S. aureus in the two study populations. Future research may be required to establish whether such differences in nasal S. aureus carriage are linked to socio-economic differences between urban and rural communities in this African country.     

Molecular epidemiology and outcome of Helicobacter pylori infection in Thailand: a cultural cross roads

ABSTRACT Background. Thailand is at the cultural cross roads between East and South Asia. It has been suggested that this is also the region where the predominant Helicobacter pylori (H. pylori) genotype changes from East Asian to South Asian. Methods. We compared the molecular epidemiology and outcome of H. pylori infections among different ethnic groups in Thailand (Thai, Thai-Chinese and Chinese). H. pylori isolates were genotyped by polymerase chain reaction based on cagA, cag right end junction and vacA genotypes. Results. Ninety-eight isolates from 38 ethnic Thai, 20 ethnic Chinese and 40 Thai-Chinese were categorized into East Asian (45%), South/Central Asian (26%), Western (1%) or mixed type (29%). The East Asian genotype was the most common among Chinese (85%) and Thai-Chinese (55%) (p <.01 compared to ethnic Thai). The ethnicity of the mother among mixed Thai-Chinese marriages predicted the genotype of the child's H. pylori (e.g. when the mother was Chinese, 84% had East Asian type vs. 29% when the mother was Thai) (p <.001). Gastric cancer was common among ethnic Chinese with East Asian genotype (e.g. all Chinese with gastric cancer or peptic ulcer disease had East Asian genotype, whereas only 40% of Chinese with gastritis had this genotype). Conclusions. Immigration, intermarriage and the variety of H. pylori genotypes in Thailand suggest that Thailand is an ideal site for epidemiological studies attempting to relate H. pylori genotypes and host factors to outcome. Our data also support the hypothesis that the primary caretaker of the children is most likely the source of the infection.     

Prevalence of Helicobacter pylori in Georgian patients with dyspepsia

BACKGROUND: Georgia has showed a high prevalence of peptic ulcer disease (PUD), but the prevalence of Helicobacter pylori in this country is practically unknown. The purpose of this study was to determine the prevalence of H. pylori and specific genotypes in different populations in Georgia. MATERIALS AND METHODS: We studied 62 patients from several hospitals in Tbilisi, Georgia. More than 55% of patients had PUD. We determined H. pylori presence as well as specific genotypes cagA and vacA by polymerase chain reaction. In addition, we studied serum samples from 94 healthy persons to determine H. pylori and CagA prevalence by ELISA. RESULTS: We found a high prevalence of H. pylori and CagA in the healthy population (70.2 and 57.4%, respectively) and a high prevalence of CagA among the H. pylori-positive persons (71.2%). Prevalence increased with age as reported in other countries (p = .05). Among symptomatic persons, we found nearly the same high prevalence of H. pylori (64.5%) as in the asymptomatic population. Furthermore, in symptomatic H. pylori patients, we found 65.0 and 67.5% prevalence of cagA and vacA, respectively. For 33 patients with PUD, 24 patients (72.7%) were H. pylori positive and 66.7% of them were cagA positive. In contrast, among the patients with non-ulcer dyspepsia (NUD), 16 (55.2%) were H. pylori positive and 62.5% of them were colonized with cagA-positive strains. H. pylori and cagA prevalence were not significantly different between PUD and patients with NUD. CONCLUSIONS: We confirmed that among individuals in Georgia, the prevalence of H. pylori is high and cagA-positive strains were equally present among H. pylori-positive patients with PUD and NUD and asymptomatic persons.     

Isolation and genotyping of Helicobacter pylori from untreated municipal wastewater

For this study, we isolated Helicobacter pylori from wastewater by a series of steps beginning with immunomagnetic separation and cell culture. After Gram staining and three standard microbial tests, the 16S rRNA sequences of a total of 23 out of 37 putative H. pylori isolates were verified by PCR. Eleven H. pylori isolates were genotyped and fell into four vacA classes: those with the vacA allelic variants s1a and m1, s1b and m1, s2 and m2, or s2 and m1. Most H. pylori isolates were of the vacA s1a/m1 type, which has been shown to be associated with advanced diseases based on genotyping of H. pylori from gastric cancer patients. These results demonstrated that H. pylori survives in water and may be a potential source of H. pylori transmission, especially where water is not adequately treated.     

Spatial heterogeneity in genetic relatedness among house sparrows along an urban-rural gradient as revealed by individual-based analysis

Understanding factors that shape patterns of kinship in sedentary species is important for evolutionary ecologists as well as conservation biologists. Yet, how patterns of relatedness are hierarchically structured in space remains poorly known, even in common species. Here, we use information from 16 polymorphic microsatellite DNA markers to study how small-scale kinship structure varies among house sparrows (Passer domesticus) along an urban-rural gradient. Average levels of relatedness were higher among urban individuals than among individuals from rural areas, suggesting lower rates of dispersal in more built-up habitats. Comparison of observed levels of relatedness with simulated distributions of known kinship values showed that central urban individuals had the highest proportion of closely related conspecifics in their immediate neighbourhood. Spatial auto-correlograms supported this small-scale genetic structure and further indicated stronger effects of genetic drift and/or limited dispersal in urban populations. Results of this study underscore the importance of individual-level analyses as a complementary approach to traditional population-level analyses when studying genetic population structure over small spatial scales.     

Body height in relation to rural-urban migration in Poland

A survey was conducted among 2800 students studying in Wroc?aw, Poland. The questionnaire included questions on the body height of the students and their parents, and place of residence and migration patterns of the students themselves, their parents and their grandparents. Body height in both students and their parents was positively correlated with the size of their place of residence. This was particularly true for male students and their fathers. Body height in students and parents from mobile families was not significantly different from that of their peers from non-mobile families. Body height in mobile individuals was generally between that of non-mobile individuals from rural areas and that of non-mobile individuals from large urban centres. Students from families that had migrated from smaller urban centres to larger ones were taller than students from families that had migrated from rural areas to urban centres. Body height in students was also correlated with the kind of migration that took place. In the students' mothers, body height was higher if the maternal grandparents moved from smaller urban centres to larger urban centres than if the maternal grandparents moved from rural areas to urban centres. In female students, body height depended on whether their mothers had migrated from smaller places of residence to larger places of residence, but was not affected by the degree of migration. Intra-generational migration during the generation of the students' grandparents was associated with increased body height in the students' mothers. On the other hand, intergenerational migration during the generations of the students' grandparents and parents was associated with increased body height in the students' fathers and in female students. Body height was not a reliable indicator of whether an individual migrated from rural areas to Wroc?aw. Far more reliable indicators were the size of the place the student lived their whole life and whether the family had lived in an urban environment for at least two generations.     

Intrafamilial transmission of Helicobacter pylori among the population of endemic areas in Japan

BACKGROUND: Helicobacter pylori (H. pylori) infection is a worldwide phenomenon related to several gastrointestinal diseases. However, because many aspects concerning the route of transmission remain unclear, we performed this epidemiologic study to clarify the route of intrafamilial transmission of H. pylori. MATERIALS AND METHODS: A retrospective study was performed in three widely separate areas in Japan to investigate the prevalence of H. pylori infection. In 1993, 613 residents were tested as were 4136 in 2002, including 1447 family members of 625 families. Antibody to H. pylori (anti-H. pylori) was determined by enzyme-linked immunosorbent assay. RESULTS: In 2002, the age-adjusted anti-H. pylori prevalence in Hoshino Village (67.5%) was significantly higher than in Kasuya Town (55.0%) and in Ishigaki City (54.7%) (p < .0001, p = .0039, respectively). The age-adjusted anti-H. pylori prevalence of Ishigaki City significantly decreased from 1993 (68.4%) to 2002 (52.5%), showing an age cohort effect. However, the prevalence did not significantly differ in children aged 0-6 years of Ishigaki City between 1993 (9.6%) and 2002 (10.3%). A familial analysis in 2002 demonstrated that the prevalence of anti-H. pylori was significantly higher in children with anti-H. pylori-positive (21.6%, 22 of 102) than with -negative mothers (3.2%, 3 of 95) (p < .0001, by Mantel-Haenszel test), whereas there was no significant difference between children with anti-H. pylori-positive and -negative fathers. Moreover, the prevalence was significantly higher in wives with anti-H. pylori-positive (64.0%, 208 of 325) than with -negative husbands (46.5%, 80 of 172) (p = .0071, by Mantel-Haenszel test) and in husbands with anti-H. pylori-positive (72.2%, 208 of 288) than with -negative wives (56.0%, 117 of 209) (p = .0106, by Mantel-Haenszel test). CONCLUSIONS: In the last decade, H. pylori infection decreased in the general population of Japan by improvement of general hygiene conditions, but did not differ in young children, most likely because of mother-to-child transmission.     

AP—PCR结合进化树分析在幽门螺杆菌地域起源特征研究中的价值

目的探讨随机引物PCR（Arbitrary primerPCR,AP—PCR）结合克隆测序及生物信息学分析等方法在研究幽门螺杆菌（Helicobacter pylori,Hpylori）菌株地域起源特征中的价值和意义。方法针对临床分离培养的Hpylori菌株的基因组DNA,采用一组10nt的寡核苷酸引物进行随机PCR扩增,选取相对保守的片段进行回收、克隆及测序,测序的基因序列提交GenBank数据库进行序列相似性的BLAST比对,收集BLAST比对得到的同源性较高不同地域来源螺杆菌的对应序列,用ClustalX软件进行排序,采用Mega4．0软件中的邻位相连法（Neighbor-joining）和最大简约法（Maximum—parsimony）进行进化树分析。结果随机引物扩增及筛选克隆测序得到的基因产物为NADH脱氢酶G和H亚单位的部分编码序列,与27株不同地域来源H．pylori及1株猫科动物来源螺杆菌菌株的同源性均高达90％以上,表明Hpylori中NADH脱氢酶基因序列为保守结构,进化树分析显示：采用AP．PCR方法得到的Hpylori临床菌株的基因序列,显示出东亚菌株来源的遗传特征,与具有东亚菌株特征的美洲秘鲁Sat464和Shi470菌株、韩国的52、51菌株、日本的1757菌株遗传距离较近,与南亚、欧洲菌株距离较远,与非洲的SouthAffica7菌株和猫科动物来源的Sheeba菌株的遗传距离最远。结论不仅某些特殊基因可以反映地域差异,随机定位相对保守的基因片段同样可以反映Hpylori的地域起源特征。AP—PCR、测序等技术方法与进化树分析相结合是探讨Hpylori地域起源特征的一种更为便捷有效的新方法。     

Helicobacter pylori infection and childhood

Pediatric-based Helicobacter?pylori research continues to contribute significantly to our understanding of both clinical and pathophysiological aspects of this infection. Here, we review the published pediatric H.?pylori literature from April 2009-March 2010. Analysis of pediatric H.?pylori strains continues to suggest that cagA(+) and cagPAI competent strains are less prevalent than in adult isolates. Studies from the Middle East report a high H.?pylori prevalence and intrafamilial transmission. Data continue to show a lack of association between H.?pylori and recurrent abdominal pain of childhood, gastroesophageal reflux disease, and growth retardation. Recent probiotic trials have not shown a benefit on H.?pylori eradication in children, while sequential therapy remains an attractive therapeutic eradication strategy in children, which requires validation in different geographic regions.     

A new LDL receptor gene deletion mutation in the South African population

Summary A previous study of the low density lipoprotein (LDL) receptor gene haplotype distribution in 12 unrelated South African patients with homozygous familial hypercholesterolaemia indicated the existence of several different receptor gene mutations in this patient pool. We have now screened these subjects for large insertion or deletion mutations at their receptor gene loci by restriction fragment size analysis using the Southern blot hybridization technique. We have detected a hitherto undescribed 2.5-kb deletion, which mapped to the central region of the gene, and most likely includes all of exons 7 and 8. The deletion was confined to two of the three so-called coloured individuals in this racially divided sample. Both probands were homozygous for the deletion with a strong possibility of consanguinity in one of the families. Mendelian inheritance was shown in both families and all carriers detected manifested elevated plasma LDL cholesterol levels. The origin of the deletion is unclear but may have been present in the indigenous Khoisan population or have been brought to South Africa by early European or Indonesian settlers.