Acknowledgement to reviewers

No abstract available.

Towards a fiercely urgent expansion of laboratory medicine in Africa

No abstract available.

Effect of polyethylene glycol 20 000 on protein extraction efficiency of formalin-fixed paraffin-embedded tissues in South Africa

Background: Optimal protocols for efficient and reproducible protein extraction from formalin-fixed paraffin-embedded (FFPE) tissues are not yet standardised and new techniques are continually developed and improved. The effect of polyethylene glycol (PEG) 20 000 on protein extraction efficiency has not been evaluated using human FFPE colorectal cancer tissues and there is no consensus on the protein extraction solution required for efficient, reproducible extraction.Objective: The impact of PEG 20 000 on protein extraction efficiency, reproducibility and protein selection bias was evaluated using FFPE colonic tissue via liquid chromatography tandem mass spectrometry analysis.Methods: This study was conducted from August 2017 to July 2019 using human FFPE colorectal carcinoma tissues from the Anatomical Pathology department at Tygerberg Hospital in South Africa. Samples were analysed via label-free liquid chromatography tandem mass spectrometry to determine the impact of using PEG 20 000 in the protein extraction solution. Data were assessed regarding peptide and protein identifications, method efficiency, reproducibility, protein characteristics and organisation relating to gene ontology categories.Results: Polyethylene glycol 20 000 exclusion increased peptides and proteins identifications and the method was more reproducible compared to the samples processed with PEG 20 000. However, no differences were observed with regard to protein selection bias. We found that higher protein concentrations ( 10 µg) compromised the function of PEG.Conclusion: This study indicates that protocols generating high protein yields from human FFPE tissues would benefit from the exclusion of PEG 20 000 in the protein extraction solution.

African countries established COVID-19 testing in one month: Here’s how they did it

Background: As a novel and deadly acute respiratory syndrome, which later became known as coronavirus disease 2019 (COVID-19), spread beyond China in late January 2020, there were no laboratories in Africa that could test for the disease. However, in early March, just over a month later, 42 African countries had developed the expertise and resources to perform COVID-19 testing. Our goal was to document this public health success story, learn from it, and use it to inform future public health action.Intervention: Three groups were primarily responsible for establishing COVID-19 testing capacity in Africa. The first group comprised early test manufacturers who reacted with incredible speed and ingenuity early in the pandemic, such as the German company TIB MolBiol that developed a molecular test for COVID-19 before the SARS-CoV-2 genome sequence was available. The second group included private and public donors such as the Jack Ma Foundation, and the last were the coordinators of the rollout, such as the World Health Organization and the Africa Centres for Disease Control and Prevention (CDC).Lessons learnt: The first lesson was that speed is critical, especially during a crisis. It was also demonstrated that being a predictable and transparent trusted institution opens doors and improves effectiveness. Africa CDC, which was only three years old, was able to secure significant resources from external partners and rapidly build substantial testing capacity within Africa because it is a trusted institution.Recommendations: Low- and middle-income countries must build local trusted institutions to better prepare for public health challenges.

Relationship between amino acid ratios and decline in estimated glomerular filtration rate in diabetic and non-diabetic patients in South Africa

Background: Diabetic kidney disease is a major complication resulting from type 1 and type 2 diabetes. Currently, the microalbuminuria test is used to monitor renal function; however, it does not detect albumin until progressive loss of renal function has occurred.Objective: This study analysed the relationship between changes in amino acid ratios and estimated glomerular filtration rate (eGFR) decline in diabetic and non-diabetic patients.Methods: Urine samples were collected from participants between February 2019 to April 2019 and analysed from November 2020 to January 2021. Diabetic (glycated haemoglobin 6.4%) and non-diabetic patients (glycated haemoglobin ≤ 6.4%) from Chris Hani Baragwanath Hospital, South Africa, were further categorised based on the degree of renal function predicted by the eGFRs. Amino acids were quantified using tandem mass spectrometry to determine the concentrations and ratios of tyrosine/phenylalanine, ornithine/arginine, arginine/citrulline and citrulline/ornithine at different stages of the chronic kidney disease.Results: Among diabetic patients, the tyrosine/phenylalanine ratio showed a statistically significant increase (p = 0.04) as the eGFR declined from stage 1 to stage 4; the ornithine/arginine ratio showed a strong negative correlation with eGFR. The citrulline/ornithine ratio differed between the diabetic and non-diabetic patients in stage 1 of chronic kidney disease.Conclusion: Amino acid ratios (ornithine/arginine and tyrosine/phenylalanine) are affected by the progression of diabetes and can be correlated to renal function. The citrulline/ornithine ratios differ between the studied groups in stage 1 of the disease and may be utilised to predict the onset of chronic kidney disease.

Re-decontamination of liquid mycobacterial cultures: Additional Mycobacterium tuberculosis yield in the era of Xpert MTB/RIF Ultra in Cape Town, South Africa

A retrospective review of liquid mycobacterial cultures was performed at a laboratory in South Africa from 01 January 2018 to 31 December 2018 to assess the increased yield in detecting Mycobacterium tuberculosis complex following sample re-decontamination. Only 9 of 99 (9%) re-decontaminated samples were culture positive for M. tuberculosis complex. Xpert MTB/RIF Ultra, concurrently performed on 7 of the 9 samples, detected M. tuberculosis complex in all but 1 sample. Re-decontamination of non-sterile samples did not increase the M. tuberculosis complex yield enough to offset the financial costs and additional labour in a laboratory that utilises the Xpert MTB/RIF Ultra system as a first-line diagnostic modality.

Establishing the cost of Xpert MTB/RIF mobile testing in high-burden peri-mining communities in South Africa

Background: Globally, tuberculosis remains a major cause of mortality, with an estimated 1.3 million deaths per annum. The Xpert MTB/RIF assay is used as the initial diagnostic test in the tuberculosis diagnostic algorithm. To extend the national tuberculosis testing programme in South Africa, mobile units fitted with the GeneXpert equipment were introduced to high-burden peri-mining communities.Objective: This study sought to assess the cost of mobile testing compared to traditional laboratory-based testing in a peri-mining community setting.Methods: Actual cost data for mobile and laboratory-based Xpert MTB/RIF testing from 2018 were analysed using a bottom-up ingredients-based approach to establish the annual equivalent cost and the cost per result. Historical cost data were obtained from supplier quotations and the local enterprise resource planning system. Costs were obtained in rand and reported in United States dollars (USD).Results: The mobile units performed 4866 tests with an overall cost per result of $49.16. Staffing accounted for 30.7% of this cost, while reagents and laboratory equipment accounted for 20.7% and 20.8%. The cost per result of traditional laboratory-based testing was $15.44 US dollars (USD). The cost for identifying a tuberculosis-positive result using mobile testing was $439.58 USD per case, compared to $164.95 USD with laboratory-based testing.Conclusion: Mobile testing is substantially more expensive than traditional laboratory services but offers benefits for rapid tuberculosis case detection and same-day antiretroviral therapy initiation. Mobile tuberculosis testing should however be reserved for high-burden communities with limited access to laboratory testing where immediate intervention can benefit patient outcomes.

Corrigendum: Brucellosis – Laboratory workers’ nightmare come true: A case study

No abstract available.

Impact of COVID-19 on blood donation and supply in Africa

No abstract available.