African Journal of Laboratory Medicine最新文献

{"title":"Challenges and complexities in evaluating severe acute respiratory syndrome coronavirus 2 molecular diagnostics during the COVID-19 pandemic","authors":"L. Scott, L. Noble, A. Singh-Moodley, T. Kahamba, D. Hardie, W. Preiser, W. Stevens","doi":"10.4102/ajlm.v11i1.1429","DOIUrl":"https://doi.org/10.4102/ajlm.v11i1.1429","url":null,"abstract":"","PeriodicalId":45412,"journal":{"name":"African Journal of Laboratory Medicine","volume":" ","pages":""},"PeriodicalIF":1.1,"publicationDate":"2022-04-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"48045439","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Impact of pre-COVID-19 epidemic preparedness on the trajectory of the pandemic in African countries","authors":"T. Maruta, S. Moyo","doi":"10.4102/ajlm.v11i1.1571","DOIUrl":"https://doi.org/10.4102/ajlm.v11i1.1571","url":null,"abstract":"Background The novel coronavirus disease 2019 (COVID-19), declared a pandemic by the World Health Organization (WHO) in March 2020, has taught us about the importance of epidemic preparedness. Objective We analysed the pre-COVID-19 preparedness of sub-Saharan African countries and how this may have influenced the trajectory of COVID-19 cases. Methods The WHO Joint External Evaluation (JEE) tool and the Global Health Security (GHS) Index were used to determine the epidemic preparedness of countries in the WHO African Region. The relationship between pre-COVID-19 preparedness and the reported number of cases per million people was evaluated over the first 120 days of the first reported case in each country, between February 2020 and September 2020. Results The overall performance of the 42 countries was 40% in the 19 JEE core capacities and 32% in the six GHS Index indicators. At Day 1, the mean number of cases per million population was significantly higher among countries rated as ‘prepared’ in the JEE legislation, policy and finance (p = 0.03), ports of entry (p = 0.001), and international health regulation coordination, communication and advocacy (p = 0.03) categories. At Day 90, countries rated as ‘prepared’ in the national laboratory systems (p = 0.05) and real-time surveillance (p = 0.04) JEE categories had statistically significantly fewer cases per million population. Conclusion This analysis highlights the importance of building capacity for pandemic preparedness in Africa. The WHO African Region was not adequately prepared for the COVID-19 pandemic as measured by the WHO JEE tool and the GHS Index.","PeriodicalId":45412,"journal":{"name":"African Journal of Laboratory Medicine","volume":" ","pages":""},"PeriodicalIF":1.1,"publicationDate":"2022-03-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"43692461","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Retrospective analysis of Vitek®2 performance compared to manual broth micro-dilution for colistin susceptibility testing of Acinetobacter baumanniicomplex isolates in South Africa","authors":"Vuyolwethu Fadana, Teena Thomas, N. von Knorring","doi":"10.4102/ajlm.v11i1.1597","DOIUrl":"https://doi.org/10.4102/ajlm.v11i1.1597","url":null,"abstract":"The manual broth micro-dilution (mBMD) is the recommended reference method for colistin minimum inhibitory concentration determination; however, it is not as readily available in South Africa as the Vitek®2. This retrospective study compared the performance of Vitek®2 against mBMD in determining the colistin minimum inhibitory concentration of 337 extensively drug-resistant Acinetobacter baumannii complex isolates. Vitek®2 yielded a categorical agreement of 89%, an essential agreement of 56%, a major error rate of 8% and a very major error rate of 55%. The Vitek®2 is not an alternative to mBMD for colistin susceptibility testing.","PeriodicalId":45412,"journal":{"name":"African Journal of Laboratory Medicine","volume":" ","pages":""},"PeriodicalIF":1.1,"publicationDate":"2022-02-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"46240293","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Red cell distribution width as a surrogate marker of haemoglobinopathies in western Kenya.","authors":"Benard M Mutua,&nbsp;George Sowayi,&nbsp;Patrick Okoth","doi":"10.4102/ajlm.v11i1.1644","DOIUrl":"https://doi.org/10.4102/ajlm.v11i1.1644","url":null,"abstract":"<p><strong>Background: </strong>Haemoglobinopathies are inherited haemoglobin disorders that result in anaemia characterised by erythrocyte anisopoikilocytosis. Red cell distribution width (RDW) measures anisopoikiloytosis and is readily reported by haematology analysers as a complete blood count parameter. The utility of RDW as a diagnostic marker of haemoglobinopathies in Kenya remains undetermined and undocumented.</p><p><strong>Objective: </strong>This study aimed to determine the diagnostic efficacy of RDW in discriminating haemoglobinopathy and haemoglobinopathy-free cases in Kenya.</p><p><strong>Methods: </strong>The case-control study used randomly selected haematology analyser outputs for haemoglobinopathy-free (241, 49.4%) and haemoglobinopathy cases (247, 50.1%) aged 1 month to 66 years old tested in the Aga Khan Hospital, Kisumu, and its satellite centres in western Kenya from 01 January 2015 to 31 December 2020. Results were verified using high performance liquid chromatography. The receiver operating characteristic (ROC) curve was used to evaluate the diagnostic power of RDW as a biomarker for sickle cell disease (SCD) and sickle cell trait phenotypes and β-thalassaemia.</p><p><strong>Results: </strong>The RDW showed diagnostic significance in SCD phenotypes at 21.1 ROC curve coordinate with 67.7% sensitivity, 90.0% specificity, 0.789 accuracy, 70.5% positive predictive validity, 88.8% negative predictive validity, 6.77 positive likelihood ratio, 0.36 negative likelihood ratio and 18.94 (11.4-31.4) odds ratio.</p><p><strong>Conclusion: </strong>An RDW of 21.1% is potentially a predictor of SCD haemoglobin phenotypes and should be included in the haematology screening algorithm as a critical value, above which suspected cases qualify to be investigated for SCD.</p>","PeriodicalId":45412,"journal":{"name":"African Journal of Laboratory Medicine","volume":"11 1","pages":"1644"},"PeriodicalIF":1.1,"publicationDate":"2022-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC9082283/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"10304744","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"The application of sigma metrics in the laboratory to assess quality control processes in South Africa.","authors":"Marli van Heerden,&nbsp;Jaya A George,&nbsp;Siyabonga Khoza","doi":"10.4102/ajlm.v11i1.1344","DOIUrl":"https://doi.org/10.4102/ajlm.v11i1.1344","url":null,"abstract":"<p><strong>Background: </strong>Laboratories use quality control processes to monitor and evaluate analytical performance in terms of precision and bias. Sigma metrics provide an objective assessment of laboratory quality using the total allowable error as an additional parameter.</p><p><strong>Objective: </strong>This study aimed to determine the sigma metrics of analytes when using different total allowable error guidelines.</p><p><strong>Methods: </strong>A retrospective analysis was performed on 19 general chemistry analytes at Charlotte Maxeke Johannesburg Academic Hospital in South Africa between January 2017 and December 2017. Sigma metrics were calculated on two identical analysers, using internal quality control data and total allowable error guidelines from the Ricos biological variation database and three alternative sources (the Royal College of Pathologists of Australasia, the Clinical Laboratory Improvements Amendment, and the European Federation of Clinical Chemistry and Laboratory Medicine).</p><p><strong>Results: </strong>The sigma performance was similar on both analysers but varied based on the guideline used, with the Clinical Laboratory Improvements Amendment guidelines resulting in the best sigma metrics (53% of analytes on one analyser and 46% on the other had acceptable sigma metrics) and the Royal College of Pathologists of Australia guidelines being the most stringent (21% and 23%). Sodium and chloride performed poorly across all guidelines (sigma < 3). There were also month-to-month variations that may result in acceptable sigma despite poor performance during certain months.</p><p><strong>Conclusion: </strong>The sigma varies greatly depending on the total allowable error, but could be a valuable tool to save time and decrease costs in high-volume laboratories. Sigma metrics calculations need to be standardised.</p>","PeriodicalId":45412,"journal":{"name":"African Journal of Laboratory Medicine","volume":"11 1","pages":"1344"},"PeriodicalIF":1.1,"publicationDate":"2022-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC9257767/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"9590980","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Hepatitis B virus infection and HBeAg positivity among pregnant women in South West Uganda.","authors":"Naome Mugabiirwe,&nbsp;Rogers Kalyetsi,&nbsp;Richard Ayella,&nbsp;James Obote,&nbsp;Frank Ssedyabane","doi":"10.4102/ajlm.v11i1.1784","DOIUrl":"https://doi.org/10.4102/ajlm.v11i1.1784","url":null,"abstract":"<p><strong>Background: </strong>Hepatitis B virus is a public health burden in Uganda, yet little is known about its epidemiology in pregnancy.</p><p><strong>Objective: </strong>This study aimed at determining the prevalence and associated risk factors of hepatitis B virus infection among pregnant women attending antenatal care at the Kyazanga Health Centre IV in Lwengo District, Uganda.</p><p><strong>Methods: </strong>This cross-sectional study was conducted from April 2021 to June 2021 and analysed qualitative data that were collected using a structured in-person questionnaire. Aseptically collected blood specimens were screened for hepatitis B virus infection using an immunochromatographic rapid diagnostic test kit. Participants who were positive for the hepatitis B surface antigen (HBsAg) were further screened for hepatitis B envelope antigen (HBeAg) using commercial rapid diagnostic test kits.</p><p><strong>Results: </strong>Out of 384 pregnant women studied, eight tested positive for HBsAg. This gave a prevalence of 2.1% (95% confidence interval: 1.0% - 4.1%); 5/8 (62.5%) were positive for HBeAg. None of the variables studied were significantly associated with HBsAg positivity among pregnant women.</p><p><strong>Conclusion: </strong>Hepatitis B viral infection is still a public health challenge in pregnant women with possible risk for vertical transmission to their babies in the study area. We recommend routine screening for hepatitis B virus in pregnancy in addition to strengthening current strategies aimed at controlling and preventing hepatitis B infection spread and transmission.</p>","PeriodicalId":45412,"journal":{"name":"African Journal of Laboratory Medicine","volume":"11 1","pages":"1784"},"PeriodicalIF":1.1,"publicationDate":"2022-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC9453108/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"9116291","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Impact of rapid centrifugation on routine coagulation assays in South Africa.","authors":"Reola Haripersadh,&nbsp;Dashini Pillay,&nbsp;Nadine Rapiti","doi":"10.4102/ajlm.v11i1.1901","DOIUrl":"https://doi.org/10.4102/ajlm.v11i1.1901","url":null,"abstract":"<p><strong>Background: </strong>The recommendation for coagulation blood samples is to centrifuge at 4000 revolutions per minute (rpm) for 15 min to produce platelet-poor plasma before analysis. Rapid centrifugation, defined as centrifuging samples at higher speeds for shorter durations, could potentially reduce turn-around times (TAT), provided sample integrity is maintained.</p><p><strong>Objective: </strong>This study assessed the impact of rapid centrifugation on routine coagulation assay results.</p><p><strong>Methods: </strong>Blood samples were collected from volunteers at Inkosi Albert Luthuli Central Hospital and King Edward VIII Hospital, Durban, KwaZulu-Natal, South Africa, from September to November 2021. Samples were centrifuged using Method A, the current standard (4000 rpm/15 min), Method B (4000 rpm/10 min), Method C (5000 rpm/10 min) and Method D (5000 rpm/5 min). Platelet count, prothrombin time, activated partial thromboplastin time, thrombin time (TT), fibrinogen and D-dimer levels were analysed and results from Methods B, C and D compared to reference Method A.</p><p><strong>Results: </strong>Platelet-poor plasma was obtained from all samples (<i>n</i> = 60) using Methods A and B, and from 33/60 (55%) samples using Methods C and D. Differences between Method A and Methods C and D for normal prothrombin time, normal D-dimer and abnormal TT results were statistically significant. Prothrombin time results correlated strongly across all methods, while TT and D-dimer results correlated poorly. Activated partial thromboplastin time and fibrinogen results showed no significant differences across all methods.</p><p><strong>Conclusion: </strong>Rapid centrifugation at 4000 rpm/10 min (Method B) showed results consistent with the reference method. This method could potentially reduce the overall TAT for routine coagulation assays.</p>","PeriodicalId":45412,"journal":{"name":"African Journal of Laboratory Medicine","volume":"11 1","pages":"1901"},"PeriodicalIF":1.1,"publicationDate":"2022-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC9724141/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"10722589","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Point-of-care testing: Connecting communities in Africa and ensuring equity in access to health and diagnostics.","authors":"Rajiv T Erasmus","doi":"10.4102/ajlm.v11i1.2072","DOIUrl":"https://doi.org/10.4102/ajlm.v11i1.2072","url":null,"abstract":"No abstract available.","PeriodicalId":45412,"journal":{"name":"African Journal of Laboratory Medicine","volume":"11 1","pages":"2072"},"PeriodicalIF":1.1,"publicationDate":"2022-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC9772737/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"10436906","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Causes of death and post-mortem testing for SARS-CoV-2 in a tertiary hospital during the COVID-19 pandemic in Ghana.","authors":"Edward Asumanu,&nbsp;Seth Attoh,&nbsp;Raymond X Servor,&nbsp;Clement Laryea,&nbsp;Mary McAddy,&nbsp;Fred Hobenu,&nbsp;Raymond Factchu,&nbsp;Kwesi Agyemang-Bediako,&nbsp;Edward O Nyarko,&nbsp;Godwin K Nyarko,&nbsp;Marcus K Moroti,&nbsp;Lawrence Edusei","doi":"10.4102/ajlm.v11i1.1766","DOIUrl":"https://doi.org/10.4102/ajlm.v11i1.1766","url":null,"abstract":"<p><strong>Background: </strong>Causes of death during the coronavirus disease 2019 (COVID-19) pandemic ranhttp://crossmark.crossref.org/dialog/?doi=10.4102/ajlm.v11i1.1766=pdf&date_stamp=2022-11-23ge from direct consequences of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection to deaths unrelated to SARS-CoV-2. Another feature of the pandemic is the post-mortem testing for SARS-CoV-2. Understanding these aspects of COVID-19 are essential in planning and limiting the impact of SARS-CoV-2 virus on healthcare systems.</p><p><strong>Objective: </strong>This study investigated the underlying causes of death and the presence of SARS-CoV-2 in bodies received at the 37 Military Hospital, Accra, Ghana, during the COVID-19 pandemic.</p><p><strong>Methods: </strong>The study was conducted from 4-27 May 2020. Deceased patients that met the inclusion criteria were prospectively selected during the expanded surveillance period for SARS-CoV-2 testing, autopsy and determination of underlying and immediate cause of death.</p><p><strong>Results: </strong>A total of 161 deceased patients were analysed with 53 autopsies. The overall positive test rate for SARS-CoV-2 was 14.9% (24/161 patients), with a positive rate of 5.0% (8/161 patients) for nasopharyngeal samples and 30.2% (16/161 patients) for bronchopulmonary samples. The underlying causes of death were not related to SARS-CoV-2 infection in 85.1% (137/161) of patients, SARS-CoV-2-associated 12.4% (20/161) and SARS-CoV-2-induced in 2.5% (4/161). Cardiovascular complications formed the most common cause of death in patients with or without SARS-CoV-2.</p><p><strong>Conclusion: </strong>There was a high positive rate of SARS-CoV-2 in post-mortem cases. However, most deaths were not caused by SARS-CoV-2 but by cardiovascular complications. The high rate of bronchopulmonary positive results for SARS-CoV-2 requires that autopsies be done in suspicious cases with negative nasopharyngeal sampling.</p>","PeriodicalId":45412,"journal":{"name":"African Journal of Laboratory Medicine","volume":"11 1","pages":"1766"},"PeriodicalIF":1.1,"publicationDate":"2022-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC9723964/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"10371671","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Oral human papilloma virus infection among dental clinic attendees in Ibadan, Nigeria.","authors":"Adedayo O Faneye,&nbsp;Oyeteju S Babalola,&nbsp;Georgina N Odaibo,&nbsp;Juwon Arotiba,&nbsp;Olufemi D Olaleye","doi":"10.4102/ajlm.v11i1.1555","DOIUrl":"https://doi.org/10.4102/ajlm.v11i1.1555","url":null,"abstract":"<p><strong>Background: </strong>Human papilloma virus (HPV) is associated with a subset of oropharyngeal squamous cell carcinoma and mouth or throat warts. However, there is currently limited information about oral HPV infections in Nigeria.</p><p><strong>Objective: </strong>This study aimed to provide information on the occurrence and circulating genotypes of HPV among patients attending three (one government and two private) dental clinics in Ibadan, Nigeria.</p><p><strong>Methods: </strong>An oral swab was collected from 231 dental clinic attendees in Ibadan between January 2016 and March 2017 and tested for HPV DNA by polymerase chain reaction targeting the E6/7 genes of the virus.</p><p><strong>Results: </strong>Twenty-three of the 231 swab samples were HPV DNA positive comprising 16 mono-infections and seven co-infections in 13 males and ten females. Genotype 16 was present in ten patients, genotype 6/11 in five, Genotype 18 and genotype 33 in four each, genotype 31 in three and genotype 39 in one. Twenty-one cases were high-risk HPV genotypes, while two were low-risk. Samples had co-infection and five had low risk type 6/11 either as single or as co-infection. Persons who had engaged in oral sex as well as those aged 21-30 years has significantly higher prevalence.</p><p><strong>Conclusion: </strong>This study showed that although HPV genotype 16 is the most common type among dental clinic attendees in Ibadan, other genotypes are also circulating and that oral sex is a risk factor for the infection. Therefore, introducing a multivalent HPV vaccine will reduce the risk of HPV-associated oropharyngeal carcinoma and other cancers in Nigeria.</p>","PeriodicalId":45412,"journal":{"name":"African Journal of Laboratory Medicine","volume":"11 1","pages":"1555"},"PeriodicalIF":1.1,"publicationDate":"2022-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC9724044/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"10371667","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}