Scielo RSS <![CDATA[African Journal of Laboratory Medicine]]> http://www.scielo.org.za/rss.php?pid=2225-201020180001&lang=pt vol. 7 num. 1 lang. pt <![CDATA[SciELO Logo]]> http://www.scielo.org.za/img/en/fbpelogp.gif http://www.scielo.org.za <![CDATA[<b>Strategic establishment of an International Pharmacology Specialty Laboratory in a resource-limited setting</b>]]> http://www.scielo.org.za/scielo.php?script=sci_arttext&pid=S2225-20102018000100001&lng=pt&nrm=iso&tlng=pt BACKGROUND: A growing number of drug development studies that include pharmacokinetic evaluations are conducted in regions lacking a specialised pharmacology laboratory. This necessitated the development of an International Pharmacology Specialty Laboratory (IPSL) in Zimbabwe. OBJECTIVES: The aim of this article is to describe the development of an IPSL in Zimbabwe. METHODS: The IPSL was developed collaboratively by the University of Zimbabwe and the University at Buffalo Center for Integrated Global Biomedical Sciences. Key stages included infrastructure development, establishment of quality management systems and collaborative mentorship in clinical pharmacology study design and chromatographic assay development and validation. RESULTS: Two high performance liquid chromatography instruments were donated by an instrument manufacturer and a contract research organisation. Laboratory space was acquired through association with the Zimbabwe national drug regulatory authority. Operational policies, standard operating procedures and a document control system were established. Scientists and technicians were trained in aspects relevant to IPSL operations. A high-performance liquid chromatography method for nevirapine was developed with the guidance of the Clinical Pharmacology Quality Assurance programme and approved by the assay method review programme. The University of Zimbabwe IPSL is engaged with the United States National Institute of Allergy and Infectious Diseases Division of AIDS research networks and is poised to begin drug assays and pharmacokinetic analyses. CONCLUSIONS: An IPSL has been successfully established in a resource-limited setting through the efforts of an external partnership providing technical guidance and motivated internal faculty and staff. Strategic partnerships were beneficial in navigating challenges leading to laboratory development and training new investigators. The IPSL is now engaged in clinical pharmacology research. <![CDATA[<b>Detection of the Janus kinase 2 V617F mutation using a locked nucleic-acid, real-time polymerase chain reaction assay</b>]]> http://www.scielo.org.za/scielo.php?script=sci_arttext&pid=S2225-20102018000100002&lng=pt&nrm=iso&tlng=pt The purpose of this study was to develop a real time polymerase chain reaction (PCR) assay for the detection of the JAK2 V617F mutation that could be used in diagnostic laboratories. Sanger sequencing and a newly developed locked nucleic-acid, real-time PCR assay were used to detect the JAK2 V617F mutation. There was 100% agreement between the sequencing and PCR analysis. Both assays were able to detect the mutation in all 24 of the 60 test specimens harbouring the mutation. <![CDATA[<b>Common uropathogens among diabetic patients with urinary tract infection at Jinja Regional Referral Hospital, Uganda</b>]]> http://www.scielo.org.za/scielo.php?script=sci_arttext&pid=S2225-20102018000100003&lng=pt&nrm=iso&tlng=pt Between June 2015 and October 2015, 159 mid-stream urine samples from diabetic patients were cultured. The prevalence of urinary tract infection was high at 22% and women were more affected compared with men (P = 0.017). Factors associated with urinary tract infection in these patients were age, sex and high blood glucose levels. Diabetic patients should be screened periodically for urinary tract infection. <![CDATA[<b>Detection of minority drug resistant mutations in Malawian HIV-1 subtype C-positive patients initiating and on first-line antiretroviral therapy</b>]]> http://www.scielo.org.za/scielo.php?script=sci_arttext&pid=S2225-20102018000100004&lng=pt&nrm=iso&tlng=pt BACKGROUND: Minority drug resistance mutations (DRMs) that are often missed by Sanger sequencing are clinically significant, as they can cause virologic failure in individuals treated with antiretroviral therapy (ART) drugs. OBJECTIVE: This study aimed to estimate the prevalence of minor DRMs among patients enrolled in a Malawi HIV drug resistance monitoring survey at baseline and at one year after initiation of ART. METHODS: Forty-one plasma specimens collected from HIV-1 subtype C-positive patients and seven clonal control samples were analysed using ultra-deep sequencing technology. RESULTS: Deep sequencing identified all 72 DRMs detected by Sanger sequencing at the level of ≥20% and 79 additional minority DRMs at the level of < 20% from the 41 Malawian clinical specimens. Overall, DRMs were detected in 85% of pre-ART and 90.5% of virologic failure patients by deep sequencing. Among pre-ART patients, deep sequencing identified a statistically significant higher prevalence of DRMs to nucleoside reverse transcriptase inhibitors (NRTIs) compared with Sanger sequencing. The difference was mainly due to the high prevalence of minority K65R and M184I mutations. Most virologic failure patients harboured DRMs against both NRTIs and non-nucleoside reverse transcriptase inhibitors (NNRTIs). These minority DRMs contributed to the increased or enhanced virologic failures in these patients. CONCLUSION: The results revealed the presence of minority DRMs to NRTIs and NNRTIs in specimens collected at baseline and virologic failure time points. These minority DRMs not only increased resistance levels to NRTIs and NNRTIs for the prescribed ART, but also expanded resistance to additional major first-line ART drugs. This study suggested that drug resistance testing that uses more sensitive technologies, is needed in this setting. <![CDATA[<b>Low-cost diagnostic test for susceptible and drug-resistant tuberculosis in rural Malawi</b>]]> http://www.scielo.org.za/scielo.php?script=sci_arttext&pid=S2225-20102018000100005&lng=pt&nrm=iso&tlng=pt BACKGROUND: Rural settings where molecular tuberculosis diagnostics are not currently available need easy-to-use tests that do not require additional processing or equipment. While acid-fast bacilli (AFB) smear is the most common and often only tuberculosis diagnosis test performed in rural settings, it is labour intensive, has less-than-ideal sensitivity, and cannot assess tuberculosis drug susceptibility patterns. OBJECTIVE: The objective of this study was to determine the feasibility of a multidrug-resistant (MDR) or extensively drug-resistant (XDR)-tuberculosis coloured agar-based culture test (tuberculosis CX-test), which can detect Mycobacterium tuberculosis growth and evaluate for drug susceptibility to isoniazid, rifampicin and a fluoroquinolone (i.e. ciprofloxacin) in approximately 14 days. METHOD: In this study, 101 participants were enrolled who presented to a rural health clinic in central Malawi. They were suspected of having active pulmonary tuberculosis. Participants provided demographic and clinical data and submitted sputum samples for tuberculosis testing using the AFB smear and tuberculosis CX-test. RESULTS: The results showed a high level of concordance between the AFB smear (12 positive) and tuberculosis CX-test (13 positive); only one sample presented discordant results, with the molecular GeneXpert MTB/RIF® test confirming the tuberculosis CX-test results. The average time to a positive tuberculosis CX-test was 10 days. Of the positive samples, the tuberculosis CX-test detected no cases of drug resistance, which was later confirmed by the GeneXpert MTB/RIF®. CONCLUSION: These findings demonstrate that the tuberculosis CX-test could be a reliable low-cost diagnostic method for active pulmonary tuberculosis in high tuberculosis burden rural areas. <![CDATA[<b>Using laboratory data to categorise CD4 laboratory turn-around-time performance across a national programme</b>]]> http://www.scielo.org.za/scielo.php?script=sci_arttext&pid=S2225-20102018000100006&lng=pt&nrm=iso&tlng=pt BACKGROUND AND OBJECTIVE: The National Health Laboratory Service provides CD4 testing through an integrated tiered service delivery model with a target laboratory turn-around time (TAT) of 48 h. Mean TAT provides insight into national CD4 laboratory performance. However, it is not sensitive enough to identify inefficiencies of outlying laboratories or predict the percentage of samples meeting the TAT target. The aim of this study was to describe the use of the median, 75th percentile and percentage within target of laboratory TAT data to categorise laboratory performance. METHODS: Retrospective CD4 laboratory data for 2015-2016 fiscal year were extracted from the corporate data warehouse. The laboratory TAT distribution and percentage of samples within the 48 h target were assessed. A scatter plot was used to categorise laboratory performance into four quadrants using both the percentage within target and 75th percentile TAT. The laboratory performance was labelled good, satisfactory or poor. RESULTS: TAT data reported a positive skew with a mode of 13 h and a median of 17 h and 75th percentile of 25 h. Overall, 93.2% of CD4 samples had a laboratory TAT of less than 48 h. 48 out of 52 laboratories reported good TAT performance, i.e. percentage within target > 85% and 75th percentile ≤ 48 h, with two categorised as satisfactory (one parameter met), and two as poor performing laboratories (failed both parameters). CONCLUSION: This study demonstrated the feasibility of utilising laboratory data to categorise laboratory performance. Using the quadrant approach for TAT data, laboratories that need interventions can be highlighted for root cause analysis assessment. <![CDATA[<b>Human parvovirus B19-induced anaemia in pre-school children in Ilorin, Nigeria</b>]]> http://www.scielo.org.za/scielo.php?script=sci_arttext&pid=S2225-20102018000100007&lng=pt&nrm=iso&tlng=pt Sera collected from 57 anaemic and 115 non-anaemic age-matched pre-school children in Ilorin, Nigeria, between November 2014 and December 2015 were assayed for human parvovirus B19-specific IgM antibodies by using the enzyme linked immunosorbent assay technique. A total of 17 (29.8%) anaemic children and 18 (15.7%) non-anaemic children were positive for parvovirus B19 infection. Infection with parvovirus B19 is common in this population, and screening for the virus during differential diagnosis is recommended.