Prevalence of Helicobacter pylori in HIV-infected, HAART-naïve Ugandan children: a hospital-based survey

<p>Abstract</p> <p>Background</p> <p>The aim of this survey was to determine the prevalence of and factors associated with <it>Helicobacter pylori </it>(<it>H. pylori</it>) colonization in HIV-infected, highly active antiretroviral therapy-naïve Ugandan children aged 0-12 years.</p> <p>Methods</p> <p>In a hospital-based survey, 236 HIV-infected children were tested for <it>H. pylori </it>colonization using a faecal antigen test. A standardized interview with socio-demographic information and medical history was used to assess risk factors. A cluster of differentiation 4 (CD4) cell percentage was prevalent in most children.</p> <p>Results</p> <p>The overall prevalence of <it>H. pylori </it>in the HIV-infected children was 22.5%. Age-specific prevalence was as follows: up to one year, 14.7%; 1-3 years, 30.9%; and 3-12 years, 20.7%. HIV-infected children who were more seriously affected by their disease (low CD4 cell percentage or WHO clinical stage II-IV) were less likely to be colonized with <it>H. pylori</it>. There was a trend for a lower prevalence of <it>H. pylori </it>in children who had taken antibiotics for the preceding two weeks (21.6%) than in those who had not taken antibiotics (35.7%). There was no statistically significant difference in prevalence by gender, housing, congested living, education of the female caretaker, drinking water or toilet facilities.</p> <p>Conclusions</p> <p>HIV-infected, HAART-naïve Ugandan children had a lower prevalence of <it>H. pylori </it>colonization compared with apparently healthy Ugandan children (44.3%). Children with a low CD4 cell percentage and an advanced clinical stage of HIV had an even lower risk of <it>H. pylori </it>colonization. Treatment with antibiotics due to co-morbidity with infectious diseases is a possible explanation for the relatively low prevalence.</p

The influence of the design of removable dentures on patient's voice quality

Background: The protozoan parasite Giardia intestinalis and the pathogenic bacterium Helicobacter pylori are well known for their high prevalences in human hosts worldwide. The prevalence of both organisms is known to peak in densely populated, low resource settings and children are infected early in life. Different Giardia genotypes/assemblages have been associated with different symptoms and H. pylori with induction of cancer. Despite this, not much data are available from sub-Saharan Africa with regards to the prevalence of different G. intestinalis assemblages and their potential association with H. pylori infections. Methodology/Principal Findings: Fecal samples from 427 apparently healthy children, 0-12 years of age, living in urban Kampala, Uganda were analyzed for the presence of H. pylori and G. intestinalis. G. intestinalis was found in 86 (20.1%) out of the children and children age 1&lt;5 years had the highest rates of colonization. H. pylori was found in 189 (44.3%) out of the 427 children and there was a 3-fold higher risk of concomitant G. intestinalis and H. pylori infections compared to non-concomitant G. intestinalis infection, OR = 2.9 (1.7-4.8). No significant association was found in the studied population with regard to the presence of Giardia and gender, type of toilet, source of drinking water or type of housing. A panel of 45 G. intestinalis positive samples was further analyzed using multi-locus genotyping (MLG) on three loci, combined with assemblage-specific analyses. Giardia MLG analysis yielded a total of five assemblage AII, 25 assemblage B, and four mixed assemblage infections. The assemblage B isolates were highly genetically variable but no significant association was found between Giardia assemblage type and H. pylori infection. Conclusions/Significance: This study shows that Giardia assemblage B dominates in children in Kampala, Uganda and that the presence of H. pylori is an associated risk factor for G. intestinalis infection

Faecal calprotectin concentrations in apparently healthy children aged 0-12 years in urban Kampala, Uganda: a community-based survey

<p>Abstract</p> <p>Background</p> <p>Calprotectin is a calcium and zinc binding protein, abundant in neutrophils and is extremely stable in faeces. Faecal calprotectin is used as a non-specific marker for gastrointestinal inflammation. It has a good diagnostic precision to distinguish between irritable bowel syndrome and inflammatory bowel disease. Studies have established normal concentrations in healthy children; all these studies have been performed in high-income countries. The objective of this study was to determine the concentration of faecal calprotectin in apparently healthy children aged 0-12 years in urban Kampala, Uganda.</p> <p>Method</p> <p>We tested 302 apparently healthy children aged, age 0-12 years (162 female, 140 male) in urban Kampala, Uganda. The children were recruited consecutively by door-to-door visits. Faecal calprotectin was analyzed using a quantitative enzyme-linked immunosorbent assay. Faeces were also tested for <it>Helicobacter pylori (H. pylori) </it>antigen, for growth of enteropathogens and microscopy was performed to assess protozoa and helminths. A short standardized interview with socio-demographic information and medical history was obtained to assess health status of the children.</p> <p>Results</p> <p>In the different age groups the median faecal calprotectin concentrations were 249 mg/kg in 0 < 1 year (n = 54), 75 mg/kg in 1 < 4 years (n = 89) and 28 mg/kg in 4 < 12 years (n = 159). There was no significant difference in faecal calprotectin concentrations and education of female caretaker, wealth index, gender, habits of using mosquito nets, being colonized with <it>H. pylori </it>or having other pathogens in the stool.</p> <p>Conclusion</p> <p>Concentrations of faecal calprotectin among healthy children, living in urban Ugandan, a low-income country, are comparable to those in healthy children living in high-income countries. In children older than 4 years, the faecal calprotectin concentration is low. In healthy infants faecal calprotectin is high. The suggested cut-off concentrations in the literature can be used in apparently healthy Ugandan children. This finding also shows that healthy children living under poor circumstances do not have a constant inflammation in the gut. We see an opportunity to use this relatively inexpensive test for further understanding and investigations of gut inflammation in children living in low-income countries.</p

Helicobacter pylori and faecal calprotectin in apparently healthy and HIV-infected Ugandan children

Abstract Gastrointestinal dysfunction, often presenting as diarrhoea, is one of the major causes of morbidity and mortality among children in low-income countries. It is estimated that 56% of child deaths were attributable to malnutrition's potentiating effects in children living in lowincome countries. There are numerous gastrointestinal problems in children in low-income countries, in particularly in human immunodeficiency virus (HIV) infected children. The gastrointestinal tract is the largest immunological site of the body and HIV infection profoundly impacts on gut function and disease development. Most studies of the gastrointestinal function in patients in low-income countries have been performed among adults. The objectives of this thesis are: 1) to examine the prevalence of H. pylori in apparently healthy urban Ugandan children and in HIV-infected, highly active anti-retroviral therapy (HAART) naïve children in the same geographical area, and 2) to examine if a faecal marker for gut inflammation, faecal calprotectin, can be used in children in a low-income country living in poor sanitary conditions, and if the marker can be used in an HIV-infected population. Two surveys were conducted in urban Kampala, Uganda. The first was community-based, in children aged 0-12 years, and conducted by door-to-door visits in a neighbourhood characterised by slum-like living conditions. The second survey was hospital-based at the Department of Paediatrics and Child Health, Mulago National Referral Hospital, Kampala where all HIV-infected, HAART naïve children admitted were invited to participate. A questionnaire was used in both surveys to address questions about medical conditions and socio-economic factors. Faeces were examined for H. pylori by using a rapid monoclonal antigen test. Faecal calprotectin was analysed using the ELISA technique. The overall prevalence of H. pylori antigen in apparently healthy urban Ugandan children aged 0-12 years was 44.3%. Early colonization was common with 28.7% in children younger than 1 year of age. There was a steady increase with age (1<3 years 46.0%, 3<6 years 51.7%, and 6<9 years 54.8%). Children living in permanent houses had a significantly lower colonization rate (38.5%) compared to those living in semi-permanent houses, 48.6%. HIV-infected children had a lower overall prevalence (22.5%). Age specific prevalence’s were; 14.7% in infants 0<1 year, 30.9% among toddles 1<3 years, and 20.7% for children 3<12 years. HIV-infected children more seriously affected by their disease (lower CD4 cell percentage or WHO clinical stage II-IV) were less likely to be colonized with H. pylori. Median faecal calprotectin concentrations in apparently healthy Ugandan children were comparable to those found in children living in high-income countries. They were 249mg/kg in infants 0<1 year (n=54), 75mg/kg among toddlers 1<4 years (n=89), and 28mg/kg for children 4<12 years (n=159). There was no significant difference in faecal calprotectin concentration when considering the education of female caretaker, wealth index, gender, habits of using mosquito nets, being colonized with H. pylori or having other pathogens in the stool. In the HIV-infected children, median faecal calprotectin concentrations were different from those in apparently healthy children. They were 208mg/kg in infants 0<1 year, 171mg/kg among toddlers 1<4 years, and 62mg/kg for children 4<12 years. HIV-infected children more seriously affected by their disease (lower CD4 cell percentage) or diarrhoea at enrolment had a higher median faecal calprotectin concentration. In conclusion, H. pylori colonization among apparently healthy urban Ugandan children is common at an early age and increases with age. The prevalence among HIV-infected children in the same geographical area is only about half. Faecal calprotectin is also a marker for gut inflammation that is well suited for use also in children in low-income countries, with the same cut-off values as suggested for children living in high-income countries. Faecal calprotectin can also be used as a tool also in an HIV-infected population for evaluation of gut inflammation. We found calprotectin to be higher in those HIVinfected children with more advanced disease, regardless of age

Common Coinfections of Giardia intestinalis and Helicobacter pylori in Non-Symptomatic Ugandan Children

Background: The protozoan parasite Giardia intestinalis and the pathogenic bacterium Helicobacter pylori are well known for their high prevalences in human hosts worldwide. The prevalence of both organisms is known to peak in densely populated, low resource settings and children are infected early in life. Different Giardia genotypes/assemblages have been associated with different symptoms and H. pylori with induction of cancer. Despite this, not much data are available from sub-Saharan Africa with regards to the prevalence of different G. intestinalis assemblages and their potential association with H. pylori infections. Methodology/Principal Findings: Fecal samples from 427 apparently healthy children, 0–12 years of age, living in urban Kampala, Uganda were analyzed for the presence of H. pylori and G. intestinalis. G. intestinalis was found in 86 (20.1%) out of the children and children age 1<5 years had the highest rates of colonization. H. pylori was found in 189 (44.3%) out of the 427 children and there was a 3-fold higher risk of concomitant G. intestinalis and H. pylori infections compared to non-concomitant G. intestinalis infection, OR = 2.9 (1.7–4.8). No significant association was found in the studied population with regard to the presence of Giardia and gender, type of toilet, source of drinking water or type of housing. A panel of 45 G. intestinalis positive samples was further analyzed using multi-locus genotyping (MLG) on three loci, combined with assemblage-specific analyses. Giardia MLG analysis yielded a total of five assemblage AII, 25 assemblage B, and four mixed assemblage infections. The assemblage B isolates were highly genetically variable but no significant association was found between Giardia assemblage type and H. pylori infection. Conclusions/Significance: This study shows that Giardia assemblage B dominates in children in Kampala, Uganda and that the presence of H. pylori is an associated risk factor for G. intestinalis infection

Helicobacter pylori in apparently healthy children aged 0-12 years in urban Kampala, Uganda: a community-based cross sectional survey

Background Helicobacter pylori is one of the most common causes of bacterial infection in human beings. Studies have showed a high prevalence of Helicobacter pylori among people in low-income countries and colonization early in life. A monoclonal antigen test, performed on faeces, HpSA®ImmunoCardSTAT, has a high sensitivity, specificity and accuracy and the faecal test can be performed in all ages, also in resource-limited settings. The main objective of this study was to determine the prevalence and factors associated with Helicobacter pylori colonization in apparently healthy children aged 0-12 years in urban Kampala, Uganda. Method We tested 427 apparently healthy children, age 0-12 years (211 males, 216 females), in a cross sectional survey for Helicobacter pylori colonization using HpSA ®ImmunoCardSTAT. A short standardized interview with socio-demographic information and medical history was used to assess risk factors. Results The overall prevalence of Helicobacter pylori in the 427 children was 44.3% (189 out of 427). Early colonization was common, 28.7%, in children younger than 1 year of age. The age specific rates were 46.0% in children age 1- < 3 years, 51.7% in children age 3- < 6 years, 54.8% in children age 6- < 9 years and 40.0% in children age 9- < 12 years. There was a significant difference in prevalence by gender; female 38.5% versus male 49.8% and by type of housing; permanent house 38.5% versus semi-permanent house 48.6%. Congestive living and education level of the female caretaker showed a clear trend for a difference in prevalence. Factors independently associated with Helicobacter pylori colonization included: drugs taken last three months, using a pit latrine, sources of drinking water and wealth index. Conclusion The prevalence of Helicobacter pylori colonization among urban Ugandan children is high at an early age and increases with age. The impact of Helicobacter pylori colonization on children's health in Uganda needs to be further clarified

Common Coinfections of Giardia intestinalis and Helicobacter pylori in Non-Symptomatic Ugandan Children

Background: The protozoan parasite Giardia intestinalis and the pathogenic bacterium Helicobacter pylori are well known for their high prevalences in human hosts worldwide. The prevalence of both organisms is known to peak in densely populated, low resource settings and children are infected early in life. Different Giardia genotypes/assemblages have been associated with different symptoms and H. pylori with induction of cancer. Despite this, not much data are available from sub-Saharan Africa with regards to the prevalence of different G. intestinalis assemblages and their potential association with H. pylori infections. Methodology/Principal Findings: Fecal samples from 427 apparently healthy children, 0-12 years of age, living in urban Kampala, Uganda were analyzed for the presence of H. pylori and G. intestinalis. G. intestinalis was found in 86 (20.1%) out of the children and children age 1&lt;5 years had the highest rates of colonization. H. pylori was found in 189 (44.3%) out of the 427 children and there was a 3-fold higher risk of concomitant G. intestinalis and H. pylori infections compared to non-concomitant G. intestinalis infection, OR = 2.9 (1.7-4.8). No significant association was found in the studied population with regard to the presence of Giardia and gender, type of toilet, source of drinking water or type of housing. A panel of 45 G. intestinalis positive samples was further analyzed using multi-locus genotyping (MLG) on three loci, combined with assemblage-specific analyses. Giardia MLG analysis yielded a total of five assemblage AII, 25 assemblage B, and four mixed assemblage infections. The assemblage B isolates were highly genetically variable but no significant association was found between Giardia assemblage type and H. pylori infection. Conclusions/Significance: This study shows that Giardia assemblage B dominates in children in Kampala, Uganda and that the presence of H. pylori is an associated risk factor for G. intestinalis infection