Medical Technology SA
Medical Technology South Africa is published half-yearly for the Society of Medical Laboratory Technologists of South Africa. Papers on any aspect of medical laboratory science or related disciplines will be considered on merit and subject to peer review.
|Publisher||The Society of Medical Laboratory Technologists of South Africa (SMLTSA)|
|Coverage||Vol 18 Issue 1 Jun 2004 - current|
Department of Higher Education and Training (DHET)
Diabetes mellitus : economic and health burden, treatment and the therapeutical effects of Hypoxis hemerrocallidea plant
Diabetes mellitus (DM) is becoming one of the leading causes of death worldwide because of its adverse complications that include cardiovascular related diseases and chronic kidney disease. DM is considered a menace to public health due to the unavailability of adequate drugs to manage this condition, especially in poor developing countries such as those in the African continent. Proper management and treatment of this is lacking, which possibly explains escalating percentages of morbidity and mortality associated with it. In Africa, as a result of poor socio-economic conditions, it is nearly impossible to properly monitor and manage DM. Globally, the commercially available drugs used in diabetes treatment regimens have been associated with drastic side effects and are also mostly unaffordable in some developing countries (particularly in Africa), hence the need to investigate cheap and readily available medicinal plants such as Hypoxis hemerocallidea. It is important to thoroughly investigate the activities of medicinal plants in animal models to identify both their therapeutic and toxic effects. This review paper examines the potential anti-diabetic benefits of Hypoxis hemerocallidea based on experimental studies done on this plant between the years 2000 and 2016. The authors recommend that further studies on the different extracts of the plant be undertaken to discover the exact mechanisms of their action.
Type two diabetes mellitus : an overview of prevalence, pathogenesis, complications and treatment options
Type two diabetes mellitus (DM) is metabolic disorder characterised by hyperglycaemia and poses a major public health challenge due to its deleterious effects on the human vascular tree through subsequent associated morbidity and mortality. Insulin resistance and impaired insulin secretion disturb the balance by which insulin target tissues communicate with β-cells and vice versa through β-cell dysfunction, leading to increased hepatic glucose production. β-cell dysfunction and consequent destruction may be caused by any one or combination of lipotoxicity, glucose toxicity or β-cell exhaustion. Sustained hyperglycaemia will eventually result in DM, which when left untreated, will lead to the development of macro- and microvascular complications. Effective control and management of diabetes is necessary to delay the development of microvascular and macrovascular disease, and requires a concerted, multidisciplinary approach involving all healthcare workers as well as the patient to ensure compliance to a tailored treatment regime.
Bleeding disorders : functionality of global haemostasis assays in attaining clinical outcomes : a review
Many tests used to evaluate haemostasis correspond to artificially created environments. These include some of the traditional screening tests, which were established through understanding the coagulation cascade for example, the prothrombin time (PT), the activated partial thromboplastin time (aPTT) and Fibrinogen estimation. And as such, they have contributed greatly to our current knowledge of the haemostatic process. Unfortunately, these traditional laboratory tests have their limitations. Open to debate for example, is their ability to supply enough information timeously (? laboratory turnaround time) in order to diagnose and treat patients according to their phenotype.
Anarchetypical shift in haemostasis measurements using global haemostasis tests that determine the complete process in a more physiological and all-inclusive way are consequently being reevaluated.
These tests include:
- The viscoelastic tests (ROTEM/TEG) improve the treatment of acute haemorrhage, decreasing the transfusion burden, as for example in cardiac surgery and with it a more effective use of blood and blood products, thus lowering overall costs. They also provide rapid, comprehensive and accurate identification of an individual’s haemostasis state, in the laboratory or in the context of near-patient testing as point-of-care instruments. This allows clinicians to drive personalised, clinically and economically sound treatment and monitoring decisions.
- Thrombin generation measurement; although expensive is elegant. And as well as having an important role in managing haemorrhage it may be sensitive to various factors that contribute to hypercoagulation. The test may also be of value in discriminating between the different phenotypes within the population of severe haemophilia A (HA) patients. It is here to stay.
- The clot waveform analysis may be less well known (i.e. presently used as a research tool). It shows promise in staging sepsis patients, having a role in the early detection of disseminated intravascular coagulation (DIC) and also in the diagnosis and treatment-monitoring of haemophiliac patients.
- Flow perfusion chambers which while they may be the ‘ultimate’ global assay has a considerable way to go in order to become of use clinically.
Although global haemostasis tests have been available for some time, there is a renewed awareness in their potential use for assessing both normal and abnormal haemostasis. Initial data suggests that they can provide more detailed information regarding the overall haemostatic process and its disorders. However, many challenges still remain such as with the analysers themselves. These involve their trademarked technology, their expense and finally their availability.
All four methods still need more background standardisation regarding reagents, methodologies and finally interpretation of results. Much more additional information is required involving all the parameters measured and by inference, their subsequent clinical applications. The present review describes these various global haemostasis tests giving some background information, as well as clinical outcomes and lastly some information on their limitations.
Evaluation of Sebia’s CAPILLARYS 2 flex-piercing system in comparison with HYDRASYS gel system, in identifying low level monoclonal protein in serum and urine of patients with suspected multiple myeloma
Background: Challenges exist with the screening and diagnosis of multiple myeloma. These are especially relevant to cases where there are low levels of monoclonal proteins or when the monoclonal band co-migrates with the increased polyclonal immunoglobulin response. We evaluated the new automated CAPILLARYS 2 Flex-Piercing system and its capability to overcome these challenges in early cases of multiple myeloma patients where the diagnosis had been confirmed by bone marrow biopsy.
Methods: This was a comparative study using serum and urine specimens sent from patients with suspected monoclonal gammopathy and was conducted using the CAPILLARYS 2 Flex-Piercing fully-automated and the HYDRASYS semi-automated systems. Serum and urine protein electrophoresis were evaluated in both systems and where monoclonal bands were suspected or seen, immunofixation/immunotyping was evaluated to confirm the diagnosis.
Results: One hundred and sixty-six (166) serum and 49 urine samples were tested, 34 serum and 37 urine samples also had immunofixation and immunotyping done due to the presence of suspicious bands. Concordance in the IFE/IT between the two systems was 96% for serum and 76% for urine analysis. In serum results, the CAPILLARYS 2 Flex-Piercing system showed sensitivity and specificity of 100%, while the HYDRASYS gel system had a lower sensitivity of 97.14% and specificity of 99.21%. In contrast Capillary urine results showed 86.49% sensitivity and 50% specificity while HYDRASYS displayed 100% sensitivity and specificity. This contributed to the discordance observed between the two systems. In 5 of the 49 urine samples, the gel IFE system identified low level urinary free light chains, which the CAPILLARYS 2 Flex-Piercing system missed.
Conclusion: The proposed system is faster, involves less human error and has a better capability in distinguishing monoclonal bands in the background of a polyclonal response. However, in urine protein electrophoresis, the gel IFE system demonstrated an increased sensitivity for the detection of low level free light chains.
A prospective evaluation of the reticulocyte haemoglobin content (CHr) at the Charlotte Maxeke Johannesburg Academic Hospital
Introduction: The diagnosis of iron deficiency anaemia (IDA) in hospitalised patients with chronic infection and inflammation presents a challenge. Recently laboratory tests such as the reticulocyte haemoglobin content (CHr), which are independent of infection and inflammation, have become available for routine diagnostic use.
Methods: A study was conducted at the Charlotte Maxeke Johannesburg Academic Hospital in order to compare the accuracy of the CHr with that of standard haematological tests for the diagnosis of IDA. The study population included 74 adult and paediatric inpatients that were anaemic. There were 20 patients with IDA, 44 patients with anaemia of chronic disease (ACD) and 10 patients with IDA/ACD as defined according to bone marrow iron stores, supporting iron studies and markers of inflammation.
Results: CHr, mean cell volume, mean cell haemoglobin (MCH) levels were significantly lower in the IDA and IDA/ACD groups as compared to the ACD group (p<0.001). A CHr of >28 pg reliably distinguished IDA and ACD with a sensitivity of 77.78% and a specificity of 79.55%. On ROC analysis, however, the diagnostic performance of the CHr (0.84, 95% CI 0.74-0.94) was not superior to the MCH (0.84, 95% CI 0.73-0.95).
Conclusion: The CHr is a simple, cost-effective, reliable test for the diagnosis of IDA in hospitalised patients. The CHr parameter, however, is not superior to standard haematological tests.
The antimicrobial susceptibility and gene based resistance of Streptococcus agalactiae (Group B Streptococcus), in pregnant women in Windhoek (Khomas region), Namibia
Objectives: The purpose of this study was to investigate the prevalence of Streptococcus agalactiae (group B Streptococcus (GBS)) amongst pregnant women in Windhoek. In addition, antimicrobial susceptibility patterns and specific resistance genes present in the GBS isolates were also investigated.
Methods: One hundred and seventeen GBS isolates were tested from Windhoek Central Hospital Antenatal Clinic. All isolated GBS were tested against selected antimicrobials using the VITEK 2 system. Resistance genes investigated in this study included: tet(M), tet(O), erm(A/TR), mef(A/E), aphA-3 and aad-6 by means of optimised PCR.
Results: The GBS colonisation prevalence rate was 13.6%. Intermediate resistance against levofloxacin and clindamycin was 0.9% and 18.8%, respectively. Resistance against trimethoprim/sulfamethoxazole, tetracycline, erythromycin and clindamycin was 6%, 94.8%, 11.1% and 8.5%, respectively. Inducible clindamycin resistance (ICR) was detected in 5.1%. One hundred and fifteen (115/117) samples presented with gene tet(M), of which 110 showed tetracycline resistance. The five remaining isolates tested sensitive against tetracycline. Three isolates presented with gene mef(A/E) and showed erythromycin resistance. Three isolates presented with gene erm(A/TR) and ICR. Two isolates presented with ICR, but no erm(A/TR) was detected.
Conclusion: Group B Streptococus prevalence amongst the screened women in the current study was 13.6% (80/588). A high resistance to tetracycline (94.8%) (111/117) was found. Erythromycin (11.1%) (13/117), trimethoprim (6%) (7/117) and clindamycin (8.5%) (10/117) showed low level resistance. Inducible clindamycin resistance (ICR) was detected in 5.1% (6/117) of the isolates. One hundred and fifteen (n=117) samples presented with gene tet(M), of which 110 showed tetracycline resistance when comparing the results to the Vitek analysis. Three isolates presented with gene mef(A/E) and showed erythromycin resistance when comparing the results to the Vitek analysis. Three isolates presented with gene erm(A/TR) as well as ICR when comparing the results to the Vitek analysis.