scholarly journals Validation of a spectrophotometric method for GGT measurement in canine urine and determination of the urine GGT-to-creatinine ratio reference interval and biological variation in 41 healthy dogs

2018 ◽  
Vol 31 (1) ◽  
pp. 33-39
Author(s):  
Nicholas P. Ilchyshyn ◽  
Elizabeth Villiers ◽  
Paola Monti

The urine gamma-glutamyl transferase (GGT)-to-creatinine ratio has been used to monitor patients at risk of acute renal injury. We validated the spectrophotometric quantification of GGT in urine in a commercial biochemistry analyzer. The assay was precise, accurate, and linear. Intra-assay precision was 3.59% in 4 samples, with GGT concentrations of 47–195 U/L. Inter-assay precision in 3 samples with activities of 11–51 U/L was 7.74%. Accuracy was 97.3%, with an absolute bias of 2.7 U/L. Urine GGT was unaffected by hematuria, hemoglobinuria, or bacteriuria. Urine GGT was stable at 20°C and 4°C for up to 3 d. Storage by freezing at −20°C resulted in a significant reduction in enzyme activity. A pH outside the range of 6.5–8 resulted in reduced GGT activity. The biological variation of urine GGT-to-creatinine ratio provided an index of individuality of 1.6, indicating that a population-based reference interval (RI) can be used. The reference change value was calculated, and an increase in consecutive measurements >43% is required to be regarded as significant. The urine GGT-to-creatinine ratio RI obtained in a population of 41 healthy dogs was 8.5–28.5 U/g.

Author(s):  
Shuo Wang ◽  
Min Zhao ◽  
Zihan Su ◽  
Runqing Mu

Abstract Objectives A large number of people undergo annual health checkup but accurate laboratory criterion for evaluating their health status is limited. The present study determined annual biological variation (BV) and derived parameters of common laboratory analytes in order to accurately evaluate the test results of the annual healthcare population. Methods A total of 43 healthy individuals who had regular healthcare once a year for six consecutive years, were enrolled using physical, electrocardiogram, ultrasonography and laboratory. The annual BV data and derived parameters, such as reference change value (RCV) and index of individuality (II) were calculated and compared with weekly data. We used annual BV and homeostatic set point to calculate personalized reference intervals (RIper) which were compared with population-based reference intervals (RIpop). Results We have established the annual within-subject BV (CVI), RCV, II, RIper of 24 commonly used clinical chemistry and hematology analytes for healthy individuals. Among the 18 comparable measurands, CVI estimates of annual data for 11 measurands were significantly higher than the weekly data. Approximately 50% measurands of II were <0.6, the utility of their RIpop were limited. The distribution range of RIper for most measurands only copied small part of RIpop with reference range index for 8 measurands <0.5. Conclusions Compared with weekly BV, for annual healthcare individuals, annual BV and related parameters can provide more accurate evaluation of laboratory results. RIper based on long-term BV data is very valuable for “personalized” diagnosis on annual health assessments.


2016 ◽  
Vol 42 (02) ◽  
pp. 53-67
Author(s):  
Shang-Hsiu Chung ◽  
Li-Wen Chang ◽  
Tsun-Li Cheng ◽  
Chen-Jou Lin ◽  
Wen-Ying Chen ◽  
...  

Reference interval (RIs) were critical to the identification of illness. However, RIs set in one laboratory may not be appropriate for another because of biological, geographical and instrumental factors. Interpretation of clinical data using inappropriate RIs may cause misclassification of results and misdiagnosis that lead to improper treatment. RIs in Taiwan have been mostly referencing from foreign resources, it is desirable to establish one that is closer to the overall conditions in Taiwan (such as breed, climate, diseases, etc.) and to investigate its differences to foreign RIs. The present study used the American Society for Veterinary Clinical Pathology (ASVCP) guidelines to establish in-house RIs for hematological, biochemical and coagulation parameters using dogs in middle Taiwan. The results were also compared to two foreign and one local RIs. The results suggested that the hematological RIs are more comparable to foreign RIs than the biochemical and hemostatic parameters. Differences were found for biochemical parameters including gamma-glutamyl transferase (GGT), lactate dehydrogenase (LDH), lipase, uric acid, bile acid, bilirubin and magnesium; and coagulation parameters including prothrombin time (PT) and activated partial thromboplastin. In all, 18% (7/40) of the all tested parameters were different from the local RI while 38% (18/48) and 41% (19/46) of the parameters were different from the two foreign RIs. The differences in more than 30% RIs and better similarities to local RIs underscore the importance of having own RIs if possible.


2020 ◽  
Vol 9 (9) ◽  
pp. 2807 ◽  
Author(s):  
Aleksandra Gasecka ◽  
Dominika Siwik ◽  
Magdalena Gajewska ◽  
Miłosz J. Jaguszewski ◽  
Tomasz Mazurek ◽  
...  

Diabetes mellitus (DM) is a common disease worldwide. There is a strong association between DM and neurovascular and neurodegenerative disorders. The first group mainly consists of diabetic retinopathy, diabetic neuropathy and stroke, whereas, the second group includes Alzheimer’s disease, Parkinson’s disease, mild cognitive impairment and dementia. The aforementioned diseases have a common pathophysiological background including insulin resistance, oxidative stress, atherosclerosis and vascular injury. The increasing prevalence of neurovascular and neurodegenerative disorders among diabetic patients has resulted in an urgent need to develop biomarkers for their prediction and/or early detection. The aim of this review is to present the potential application of the most promising biomarkers of diabetes-related neurodegenerative and neurovascular disorders, including amylin, β-amyloid, C-reactive protein (CRP), dopamine, gamma-glutamyl transferase (GGT), glycogen synthase kinase 3β, homocysteine, microRNAs (mi-RNAs), paraoxonase 1, phosphoinositide 3-kinases, tau protein and various growth factors. The most clinically promising biomarkers of neurovascular and neurodegenerative complications in DM are hsCRP, GGT, homocysteine and miRNAs. However, all biomarkers discussed in this review could become a part of the potential multi-biomarker screening panel for diabetic patients at risk of neurovascular and neurodegenerative complications.


Author(s):  
Eduardo Martínez-Morillo ◽  
Anastasia Diamandis ◽  
Eleftherios P. Diamandis

AbstractKallikrein 6 (KLK6) is a serine protease involved in numerous cellular processes, up-regulated in many cancers and associated with some neurodegenerative disorders. The aim of this study was to establish a reference interval and estimate the biological variation of KLK6 in serum samples of adults. Furthermore, levels of this protein in patients with renal failure were also studied.Serum samples from healthy volunteers (n=136) were collected. Between 15 and 18 additional samples from four of these subjects were obtained over a period of 2 months. Samples from individuals (n=1043) who visited the University Health Network for a routine check-up were collected to study the association between KLK6 with age and gender. Samples from patients with renal failure (n=106) were also obtained and KLK6 and creatinine concentrations were analyzed by ELISA and an automated enzymatic method, respectively.The reference interval was established to be 1.04–3.93 ng/mL. The index of individuality was 0.43 and the reference change value was 35%. Only two serum samples would be required to estimate the homeostatic setting point of an individual. There is a weak but highly significant positive correlation between KLK6 and age (p<0.0001). Furthermore, there is a significant positive correlation between serum concentrations of KLK6 and creatinine (p<0.0001), in patients with renal failure.The established reference interval for KLK6 and the estimation of its biological variation will further aid in the clinical use of this protein as a serum marker of malignancy and other diseases.


Renal Failure ◽  
2014 ◽  
Vol 36 (3) ◽  
pp. 390-392 ◽  
Author(s):  
Ezgi Ersoy Yesil ◽  
Nurcan Paker ◽  
Atakan Yesil ◽  
Kadir Kayatas ◽  
Yahya Laleli ◽  
...  

Author(s):  
Carmen Ricós ◽  
Maria Vicenta Doménech ◽  
Carmen Perich

AbstractInterpretation oflaboratory test results requires comparison to some type of reference value or reference interval. These comparisons can be cross-sectional (population-based reference interval and cut-off values) or longitudinal (reference change value). Quality specifications for cross-sectional comparison have been established by determining the influence of analytical bias and imprecision on the percentage ofthe healthy population falling outside the reference limits, when sharing population-based reference intervals in a Gaussian distribution ofresults. Quality specifications for longitudinal comparisons are equally important and are often overlooked, since less work has been done in this area. Some criteria suggest that a difference between consecutive results designates a true change in a patient health status when the difference is higher than the within-subject biological variation plus the within-laboratory analytical variation. In this chapter we discuss the clinical considerations and laboratory-related factors that must be considered when quality specifications are applied to sharing reference comparisons. Real life experience shows that different analytical methods can produce comparable results when common quality goals are established, and quality can be achieved through a willingness to work together. Within the existing organization, the current specifications for analytical quality and a dedication to quality health care makes it possible to achieve transferability between laboratories within a geographic area.


2021 ◽  
Vol 17 (1) ◽  
Author(s):  
Emma M. Strage ◽  
Charles J. Ley ◽  
Johannes Forkman ◽  
Malin Öhlund ◽  
Sarah Stadig ◽  
...  

Abstract Background Obesity is associated with insulin resistance (IR) and considered a risk factor for diabetes mellitus (DM) in cats. It has been proposed that homeostasis model assessment (HOMA-IR), which is the product of fasting serum insulin (mU/L) and glucose (mmol/L) divided by 22.5, can be used to indicate IR. The objectives of this study were threefold: (i) to evaluate associations between body fat, fasting insulin, and HOMA-IR, (ii) to determine population-based reference interval of HOMA-IR in healthy lean cats, and (iii) to evaluate biological variation of HOMA-IR and fasting insulin in cats. Results 150 cats were grouped as lean or overweight based on body condition score and in 68 of the cats body fat percentage (BF%) was estimated by computed tomography. Fasting serum insulin and glucose concentrations were analysed. Statistical differences in HOMA-IR and insulin between overweight or lean cats were evaluated using Wilcoxon rank-sum test. Robust method with Box-Cox transformation was used for calculating HOMA-IR reference interval in healthy lean cats. Relations between BF% and HOMA-IR and insulin were evaluated by regression analysis. Restricted maximum likelihood ratio was used to calculate indices of biological variation of HOMA-IR and insulin in seven cats. There were significant differences between groups with overweight cats (n = 77) having higher HOMA-IR (p < 0.0001) and insulin (p = 0.0002) than lean cats (n = 73). Reference interval for HOMA-IR in lean cats was 0.1–3.0. HOMA-IR and fasting insulin concentrations showed similar significant positive association with BF% (p = 0.0010 and p = 0.0017, respectively). Within-animal coefficient of variation of HOMA-IR and insulin was 51% and 49%, respectively. Conclusions HOMA-IR and fasting insulin higher in overweight than lean cats and correlate to BF%. The established population-based reference interval for HOMA-IR as well as the indices of biological variation for HOMA-IR and fasting insulin may be used when interpreting HOMA-IR and fasting insulin in cats. Further studies are needed to evaluate if HOMA-IR or fasting insulin is useful for identifying cats at risk of developing DM.


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