Evaluation of a locally produced rapid urease test for the diagnosis of Helicobacter pylori infection

Background. The rapid urease test (RUT) is used at Groote Schuur Hospital for diagnosing Helicobacter pylori infection. This is an in-house method, which has not been validated. Objective. To validate our practice of reading the RUT immediately after endoscopy (RUT0), by comparing this with a reading at 24 hours (RUT24) and with histological analysis. Design. Ninety consecutive patients undergoing upper endoscopy over a 6-week period from October 2005 to November 2005, and in whom rapid urease testing was indicated, were included in the study. Patients with recent exposure (within 2 weeks of endoscopy) to proton pump inhibitors (PPIs), histamine receptor antagonists (H2RAs) and antibiotics (confounders) were noted and included in the cohort. Two antral and two body biopsies were taken for histological examination and a third antral biopsy was placed in the RUT bottle. Both haematoxylin and eosin and modified Giemsa staining methods were used to identify H. pylori. The RUT was read immediately (within 5 minutes of upper endoscopy) (RUT0), as per our current practice, and each specimen was re-read at 24 hours (RUT24). Sensitivity, specificity, positive and negative predictive values and the impact of confounders were calculated. Results. Of the 90 patients undergoing rapid urease testing, 39% were male and 61% were female, with a mean age of 55 years (range 22 - 79 years). Histological examination revealed H. pylori in 67.8% (N=61) of the biopsy specimens. In the 65 patients without confounders, the sensitivity and specificity of the RUT0 were 65.9% and 100% respectively, and 90.9% and 100% for RUT24. After including the 25 patients with confounders, the sensitivity and specificity were 68.8% and 100% for RUT0, and 90.1% and 100% for RUT24 respectively. Thirteen RUT0 specimens (30.9%) that were initially negative became positive at the RUT24 reading. There were 6 (9.8%) RUT0- and RUT24-negative but histology-positive specimens. Four of these 6 false-negative RUT24 results could be accounted for by a low H. pylori density on histological analysis (2 patients were taking PPIs). Confounders did not alter the sensitivity and specificity outcomes or impact on the number of false-negative RUTs. Conclusions. Our locally prepared RUT is a specific test for the detection of H. pylori infection. The sensitivity is greatly enhanced by reading the test at 24 hours. The use of PPIs, H2RAs and antibiotics preceding endoscopy did not impact significantly on the results

Evaluation of a locally produced rapid urease test for the diagnosis of Helicobacter pylori infection

Background. The rapid urease test (RUT) is used at Groote Schuur Hospital for diagnosing Helicobacter pylori infection. This is an in-house method, which has not been validated. Objective. To validate our practice of reading the RUT immediately after endoscopy (RUT0), by comparing this with a reading at 24 hours (RUT24) and with histological analysis. Design. Ninety consecutive patients undergoing upper endoscopy over a 6-week period from October 2005 to November 2005, and in whom rapid urease testing was indicated, were included in the study. Patients with recent exposure (within 2 weeks of endoscopy) to proton pump inhibitors (PPIs), histamine receptor antagonists (H2RAs) and antibiotics (confounders) were noted and included in the cohort. Two antral and two body biopsies were taken for histological examination and a third antral biopsy was placed in the RUT bottle. Both haematoxylin and eosin and modified Giemsa staining methods were used to identify H. pylori. The RUT was read immediately (within 5 minutes of upper endoscopy) (RUT0), as per our current practice, and each specimen was re-read at 24 hours (RUT24). Sensitivity, specificity, positive and negative predictive values and the impact of confounders were calculated. Results. Of the 90 patients undergoing rapid urease testing, 39% were male and 61% were female, with a mean age of 55 years (range 22 - 79 years). Histological examination revealed H. pylori in 67.8% (N=61) of the biopsy specimens. In the 65 patients without confounders, the sensitivity and specificity of the RUT0 were 65.9% and 100% respectively, and 90.9% and 100% for RUT24. After including the 25 patients with confounders, the sensitivity and specificity were 68.8% and 100% for RUT0, and 90.1% and 100% for RUT24 respectively. Thirteen RUT0 specimens (30.9%) that were initially negative became positive at the RUT24 reading. There were 6 (9.8%) RUT0- and RUT24-negative but histology-positive specimens. Four of these 6 false-negative RUT24 results could be accounted for by a low H. pylori density on histological analysis (2 patients were taking PPIs). Confounders did not alter the sensitivity and specificity outcomes or impact on the number of false-negative RUTs. Conclusions. Our locally prepared RUT is a specific test for the detection of H. pylori infection. The sensitivity is greatly enhanced by reading the test at 24 hours. The use of PPIs, H2RAs and antibiotics preceding endoscopy did not impact significantly on the results. South African Medical Journal Vol. 97 (12) 2007: pp. 1281-128

Organising Somalian, Congolese and Rwandan migrants in a time of xenophobia in South Africa: empirical and methodological reflections

Xenophobic practices pervade civil society and the state in South Africa. But its victims are not passive. Academic scholarship has not sufficiently recognised the multiple roles of refugees and asylum seekers migrant organisations in a context where refugees are required to "self-settle”. The dominant methodological focus of existing research has been on the migrant as the individual. This paper’s main research objectives are to question this focus and examine evidence of the collective responses to struggles faced by foreign African migrants and refugee groups in Cape Town. Eleven refugee and asylum seeker associations formed by Somalians, Congolese and Rwandan asylum seekers and refugees were investigated, based on extensive interviews with 11 leaders of refugee organisations. These organisations not only strongly defend migrant interests but also project a long-term view of integration into South African society. In addition, the paper concludes by arguing for a shift in the focus of research in order to show that migrant organisations are crucial in an individual’s collective security concerns, in advocacy with government institutions and in initiatives to build relationships with South Africans

The epidemiology of adolescents living with perinatally acquired HIV: A cross-region global cohort analysis

Background: Globally, the population of adolescents living with perinatally acquired HIV (APHs) continues to expand. In this study, we pooled data from observational pediatric HIV cohorts and cohort networks, allowing comparisons of adolescents with perinatally acquired HIV in "real-life" settings across multiple regions. We describe the geographic and temporal characteristics and mortality outcomes of APHs across multiple regions, including South America and the Caribbean, North America, Europe, sub-Saharan Africa, and South and Southeast Asia. Methods and findings: Through the Collaborative Initiative for Paediatric HIV Education and Research (CIPHER), individual retrospective longitudinal data from 12 cohort networks were pooled. All children infected with HIV who entered care before age 10 years, were not known to have horizontally acquired HIV, and were followed up beyond age 10 years were included in this analysis conducted from May 2016 to January 2017. Our primary analysis describes patient and treatment characteristics of APHs at key time points, including first HIV-associated clinic visit, antiretroviral therapy (ART) start, age 10 years, and last visit, and compares these characteristics by geographic region, country income group (CIG), and birth period. Our secondary analysis describes mortality, transfer out, and lost to follow-up (LTFU) as outcomes at age 15 years, using competing risk analysis. Among the 38,187 APHs included, 51% were female, 79% were from sub-Saharan Africa and 65% lived in low-income countries. APHs from 51 countries were included (Europe: 14 countries and 3,054 APHs; North America: 1 country and 1,032 APHs; South America and the Caribbean: 4 countries and 903 APHs; South and Southeast Asia: 7 countries and 2,902 APHs; sub-Saharan Africa, 25 countries and 30,296 APHs). Observation started as early as 1982 in Europe and 1996 in sub-Saharan Africa, and continued until at least 2014 in all regions. The median (interquartile range [IQR]) duration of adolescent follow-up was 3.1 (1.5-5.2) years for the total cohort and 6.4 (3.6-8.0) years in Europe, 3.7 (2.0-5.4) years in North America, 2.5 (1.2-4.4) years in South and Southeast Asia, 5.0 (2.7-7.5) years in South America and the Caribbean, and 2.1 (0.9-3.8) years in sub-Saharan Africa. Median (IQR) age at first visit differed substantially by region, ranging from 0.7 (0.3-2.1) years in North America to 7.1 (5.3-8.6) years in sub-Saharan Africa. The median age at ART start varied from 0.9 (0.4-2.6) years in North America to 7.9 (6.0-9.3) years in sub-Saharan Africa. The cumulative incidence estimates (95% confidence interval [CI]) at age 15 years for mortality, transfers out, and LTFU for all APHs were 2.6% (2.4%-2.8%), 15.6% (15.1%-16.0%), and 11.3% (10.9%-11.8%), respectively. Mortality was lowest in Europe (0.8% [0.5%-1.1%]) and highest in South America and the Caribbean (4.4% [3.1%-6.1%]). However, LTFU was lowest in South America and the Caribbean (4.8% [3.4%-6.7%]) and highest in sub-Saharan Africa (13.2% [12.6%-13.7%]). Study limitations include the high LTFU rate in sub-Saharan Africa, which could have affected the comparison of mortality across regions; inclusion of data only for APHs receiving ART from some countries; and unavailability of data from high-burden countries such as Nigeria. Conclusion: To our knowledge, our study represents the largest multiregional epidemiological analysis of APHs. Despite probable under-ascertained mortality, mortality in APHs remains substantially higher in sub-Saharan Africa, South and Southeast Asia, and South America and the Caribbean than in Europe. Collaborations such as CIPHER enable us to monitor current global temporal trends in outcomes over time to inform appropriate policy responses.info:eu-repo/semantics/publishedVersio

Towards Customary Legal Empowerment

Rule of Law and Development: Formation, Implementation and Improvement of Law and Governance in Developing Countrie

The determinants of market participation and its effect on food security of the rural smallholder farmers in Limpopo and Mpumalanga provinces, South Africa

Addressing the disproportionate burden of food insecurity in South Africa requires targeted efforts to help smallholder farmers to access markets. The purpose of this study was to assess determinants of market participation and its contribution to household food security. The secondary data used in this study were collected from 1520 respondents; however, 389 smallholder farmers participated in the market. The Household Food Insecurity Access Scale revealed that out of the total sample size, 85% of the households were food insecure while 15% were food secure. Gender of household head, receiving social grants and higher wealth index positively impacted market participation. Having a family member with HIV had a negative impact on market participation among smallholder farmers. The results from the extended ordered probit regression model showed that household size, having a family member with HIV and agricultural assistance had a positive and significant contribution to the household food insecurity situation of the smallholder farmers. On the other hand, the educational level of household head, ownership of livestock, age of household head, gender of household head, and having access to social grants had a negative and significant effect on the food insecurity status. Access to education and the market can improve household food security. Linking smallholder farmers, particularly women and aged farmers, to markets should form an intrinsic part of the government’s efforts to improve farming and food security and increase access to diversified food

Effect of swift heavy ion irradiation in the migration behavior of Xe implanted into TiN

Sintered TiN were implanted with Xe ions of 360 keV to a fluence of 1.1 × 10 16 cm −2 at room temperature (RT) and others were co-irradiated with Xe ions of 167 MeV to a fluence of 3.4 × 10 14 cm −2 and Xe ions of 360 keV to a fluence of 1.1 × 10 16 cm −2 also at RT, successively. Both samples were isochronally annealed at temperatures ranging from 1100 to 1500 °C. Both irradiations caused no amorphization of the sintered TiN, however more defects were retained in the samples implanted with only Xe (360 keV) ions. Annealing of defects retained after irradiations were found to be faster in the co-irradiated samples. The migration behavior of implanted Xe was explained by trapping and de-trapping by defects at temperatures below 1200 °C while at temperatures above 1200 °C, it was dominated by grain boundary diffusion, in the un-irradiated samples. In the co-irradiated samples, Xe migrated via fast grain boundaries. © 2019 Elsevier Lt