Advances in laboratory medicine最新文献

Cardiovascular diseases keep being the leading cause of mortality in Spain. Efforts should be intensified to identify new risk factors that may contribute to increasing cardiovascular risk. Lipoprotein(a) (Lp(a)) has been associated with a higher risk for developing aortic valve stenosis, heart failure, ischemic stroke, ischemic heart disease and peripheral arterial disease. Hyperlipoproteinemia(a) is a common health problem. Between 10 and 30 % of the world population have Lp(a) values exceeding 50 mg/dL. The scientific evidence provided in the recent years confirms an independent association between Lp(a) and the risk for having an arteriosclerotic cardiovascular event. This finding, added to the emergence of new specific therapies for reducing Lp(a) has raised interest in the quantification of this lipoprotein. The objective of this paper was to perform a review of the evidence available to identify the patients who will benefit from undergoing Lp(a) testing and determine the recommended quantification methods, the desirable concentrations, and the role of Lp(a) determination in reclassifying the cardiovascular risk of patients.

Objectives: Obesity and overweight have increased in children and adolescents in Europe in the recent years, accounting for a major global public health problem. The objective of this study was the early detection of metabolic abnormalities in overweight/obese children (8-12 years old) that may ultimately induce impaired glucose metabolism and/or cardiovascular diseases.

Methods: Lipid metabolism and metabolic control parameters were measured and monitored in a group of 61 male and female children with overweight/obesity and a group of 45 healthy, normal weight children, comparing the results obtained. Ages ranged from 8 to 12 years.

Results: Higher levels of triglycerides and insulin and lower levels of high-density lipoprotein (HDL) cholesterol and apolipoprotein A1 were observed in overweight/obese children, as compared to normal weight children. Overweight/obese children exhibited higher apolipoprotein B/apolipoprotein A1 ratio, triglyceride-glucose ratio and HOMA index and a lower low-density lipoprotein (LDL) cholesterol/apolipoprotein B ratio.

Conclusions: Obesity at an early age (8-12 years) negatively affects lipid parameters. Hence, overweight/obese children presented a more atherogenic lipid profile, manifested as higher concentrations of remnant particles and small dense LDL particles, higher insulin resistance and a higher risk for developing diabetes mellitus type 2 and cardiovascular disease, as compared to normal weight children.

Objectives: Efficient real-time PCR kits are commercially available for the detection of Chlamydia trachomatis (CT) genetic material, but at a price. As a result, cost-effective, sensitive and specific CT diagnostic tests are essential for resource limited countries. This study aims to describe the optimization of a loop mediated isothermal amplification (LAMP) assay for the detection of CT ompA DNA in urine.

Methods: Cost-saving modifications included using Bsm polymerase and a nucleic acid gel stain. Crude DNA extraction (method-1) involved centrifuging urine at 14,000 g for 30 min, heating the deposit at 95 °C for 5 min, and centrifuging again at 17,000 g for 1 min. To boost sensitivity, urinary inhibitors were diluted with phosphate-buffered saline washes and a larger urine volume was used (method-2). The LAMP-SYBR GOLD assay was incubated at 56 °C for 60 min, with nucleic acid gel stain color changes observed under UV light. Urine from 326 sexually transmitted diseases clinic attendees was tested with both LAMP-SYBR GOLD and real-time PCR, comparing sensitivity and specificity.

Results: Analytical sensitivity of the LAMP-SYBR GOLD assay was 0.8 copies per reaction volume. Compared to real-time PCR, LAMP-SYBR GOLD assay had sensitivity, specificity, positive predictive and negative predictive values of 71.4 , 99.7, 96.2, 96.7 % respectively. Five of the seven false negative results obtained with method-1 were re-tested using method-2, providing in all the cases the expected positive results.

Conclusions: The LAMP-SYBR GOLD assay showed a sensitivity of 71 % and a high specificity for detecting CT in urine with extraction method-1. The use of method-2 could increase this sensitivity, likely due to the removal of urine inhibitors.

Objectives: Myelodysplastic syndromes (MDS) are clonal hematopoietic disorders characterized by peripheral blood cytopenias, cellular dysplasia and risk for progression into acute leukemia. Recent studies reveal that some research parameters available on Sysmex XN-1000^® hematology analyzers, including immature platelet fraction (IPF), Neutrophil Granularity Index (Neu-GI), or platelet distribution width (PDW), show a relationship with dysplasia in peripheral blood. The objective of this study was to examine the association between classic and research blood count parameters and the presence of dysplasia. The secondary objective was to develop a multivariate model that allows the prediction of dysplasia with high probability.

Methods: Seventy-five patients older than 60 years with anemia, leukopenia or thrombocytopenia, without vitamin B12 and folate deficiency or hematological diseases underwent testing with the Sysmex XN-1000 analyzer.

Results: Dysplasia was confirmed in 32 % of patients, with significant differences in Neu-GI, PDW and IPF count between the groups of patients with and without dysplasia. Neu-GI was the parameter with the highest predictive value (AUC=0.98), with such value not increasing significantly after the addition of PDW or PIF. A Neu-GI value≤146ch predicts dysplasia with a positive predictive value=90 %.

Conclusions: Neu-GI is the parameter most strongly associated with dysplasia. A Neu-GI value≤146ch indicates a high probability of dysplasia and supports indication for a blood smear review. Additionally, values>152ch indicate a low probability of dysplasia.

Objectives: Hemoglobinopathies are disorders affecting the structure, function and/or production of hemoglobin. These conditions are caused by mutations in the genes encoding globin synthesis. The highly variable clinical manifestations of hemoglobin disorders range from asymptomatic forms to severe anemia. Laboratory tests are crucial for diagnosis.

Case presentation: We report the case of a patient who presented with asthenia. Since the patient had a family history of hemoglobonipathies, screening for erythropathies was performed. High-resolution liquid chromatography (HPLC) showed a normal distribution of hemoglobin levels. In contrast, capillary zone electrophoresis at alkaline pH demonstrated an unidentified rapid migration peak. Genetic testing revealed a mutation in the HBB gene causing Hofu hemoglobin disease.

Conclusions: The hemoglobin variant Hofu is slightly unstable. While heterozygous carriers most frequently remain asymptomatic, they may develop anemia in the presence of other concomitant disorders. Distinctively, the retention time of Hb Hofu on HPLC is very close to that of HbA (0) and they often elute together. Therefore, Hb Hofu may remain masked, thereby leading to the misinterpretation of test results.