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Amaç: Böbrek fonksiyonun bir belirteci olarak bilinen sistatin C’nin tümör gelişiminde inhibör etki gösterdiği düşünülmektedir. Çalışmada bilinen böbrek hastalığı olmayan mide ve kolorektal kanserli olgularla sağlıklı bireylerin serum sistatin C düzeyleri arasındaki olası farkın, serum karsinoembriyonik antijen (CEA) ve karbohidrat antijen 19-9 (CA19-9) düzeyleri arasındaki ilişkinin incelenmesi amaçlanmıştır.Materyal ve metod: Çalışmaya serum kreatinin konsantrasyonu referans aralığı içerisinde yer alan ve tahmini glomerüler filtrasyon hızı (eGFH) >60 mL/dk olan mide (n=35) ve kolorektal kanserli (n=35) hastalar ile bilinen herhangi bir sistemik hastalığı olmayan sağlıklı bireyler (n=40) dahil edilmiştir. CEA ve CA 19-9 testleri kemilüminesans temelli immün yöntemle (Beckman Coulter UniCel® DxI 800 Immunoassay System) Sistatin C analizi ise partikül yüzeyi genişletilmiş immünotürbidimetrik yöntem (Roche Diagnostics Cobas® Modular P®) kullanılarak yapılmıştır.Bulgular: Mide, KRK (kolorektal kanser) ve kontrol grupları arasında serum kreatinin konsantrasyonu açısından önemli fark izlenmezken (p=0,571) sistatin C düzeyi hasta gruplarında kontrol grubuna göre anlamlı olarak daha yüksek izlenmiştir (p0,05). Sonuç: Mide veya kolorektal kanserli olgularda serum sistatin C düzeyinin böbrek fonksiyonunun yanısıra kanser varlığından da etkilenebileceği gözlenmiştir.Anahtar Kelimeler: Sistatin C, Katepsin, Mide Kanseri, Kolorektal Kanser

Objectives Biotinidase Deficiency (BD) is an autosomal recessive metabolic disorder. However, the relationship between genotype and biochemical phenotype has not been completely elucidated yet. But still, some mutations are accepted to be associated with profound or partial deficiency. We aimed to evaluate the results of biochemical enzyme activity in accordance with the presence of genetic mutations and investigate the correlation between genotype and biochemical phenotype together in the study. Methods This retrospective study was carried out using data from medical records of 133 infants detected by the newborn screening followed by serum biotinidase activity (BA) detection with semi-quantitative colorimetric method. Mutation analysis was performed to confirm the diagnosis. In addition, the expected biochemical phenotype based on the known mutant alleles were compared with the observed biochemical phenotype. Results When confirmed with mutation analysis results, the diagnostic sensitivity and specificity of serum BA with spectrophotometric method was 93.1% and 95.1%, respectively. In 93.98% of the cases conformity was observed between the biochemical phenotype and the genotype. The c.1330 G>C(p.D444H) and c.470 G>A (p.Arg157His) were the most common allelic variants with frequencies of 63.69% and 33.75%, respectively. Conclusions The diagnostic test is supposed to have a high sensitivity to identify asymptomatic BD patients. Apparently healthy cases with almost normal enzyme activity and a variant allele in the genetic analysis were reported to present symptoms under stress conditions, which should be kept in mind. This study can be accepted as an informative report as it may contribute to the literature in terms of the allelic frequency and determination of the relation between genotype and biochemical phenotype. Also, method verification including the assessment of possible effects of non-genetic factors on BA according to the certain mutation types is warranted.

Objective Hemoglobinopathies are a common public health problem in Turkey. In the screening of these disorders in population, cation-exchange high performance liquid chromatography (HPLC) is accepted as the gold standard method. In this study, the aim was to assess four different HPLC devices used in hemoglobinopathy screening. Materials and methods A total of 58 blood samples were analyzed with four different HPLC methods (Bio-Rad variant II, Agilent 1100, Tosoh G8 and Trinity Ultra2 trademarks). Results The comparison study demonstrated a good correlation between the results of each HPLC analyzer and the reference value obtained by averaging all the HbA2 results belonging to the methods tested in the study [ (Tosoh G8 (r=0.988), Bio-Rad variant II (r=0.993), Agilent 1100 (r=0.98) and Trinity Ultra2 (r=0.992) ]. HbA2 determination in the presence of HbE was interfered in both Bio-Rad variant II and Tosoh G8. Conclusion The analyzers were found to have compatible HbA2 results but with accompanying different degrees of proportional and systematic biases. HPLC analyzers may be affected by different hemoglobin variants at different HbA2 concentrations, which is an important point to take into consideration during the evaluation of HbA2 results in thalassemia screening.

Objectives Recent advances in hematology analyzers have enabled to improve the reliability in the results and also provided additional hematological parameters. In the present study, we aimed to determine the reference ranges for automated erythrocyte and reticulocyte parameters in healthy individuals on Sysmex XN 1000 hematology analyzer. Methods One hundred and thirty-three subjects with normal physical examination and complete blood count results within the reference ranges were included in the study. Venous blood samples collected in tubes containing K2-EDTA were analyzed on Sysmex XN-1000. The references intervals for IRF, RBC He, Ret He, LFR, MFR, HFR, Delta He, Micro R, Macro R, Hypo He and Hyper He were determined according to CLSI EP28-A3c. Results The reference ranges of the parameters were estimated with 90% confidence intervals. The reference ranges were 3.4–17% for IRF, 26.9–32.8 pg for Ret-He, 25.2–30.5 pg for RBC-He and 0.5–3.7 pg for delta-He. Gender specific reference ranges were calculated for of Ret-He (male (M): 26.8–32.9 pg, female (F): 23.9–33.6 pg), RBC-He (M: 26.3–30.8 pg, F: 25.3–30.5 pg) and delta-He (M: 0.5–3.7 pg, F: 0.3–3.7 pg). Conclusions The new reticulocyte and erythrocyte parameters may be conveniently used in clinical diagnosis and follow-up of patients, as they offer reliable, automated and cheap results. Each laboratory is recommended to determine its own reference intervals considering the differences like the instrument used and population studied. Amaç Hematoloji analizörlerindeki son gelişmeler, sonuçların güvenilirliğini artırmakla birlikte, ek hematolojik parametreler de sağlamıştır. Bu çalışmada sağlıklı bireylerde otomatize eritrosit ve retikülosit parametreleri için Sysmex XN 1000 hematoloji analizörü kullanılarak referans aralıklarının belirlenmesi amaçlanmıştır. Gereç ve yöntem Fizik muayenesi normal ve tam kan sayım sonuçları referans aralık içerisinde olan 133 kişi çalışmaya dahil edilmiştir. K2-EDTA’lı tüplere toplanan venöz kan örnekleri Sysmex XN-1000 analizöründe analiz edilmiştir. IRF, RBC He, Ret He, LFR, MFR, HFR, Delta He, Micro R, Macro R, Hypo He ve Hyper He için referans aralıkları CLSI EP28-A3c′ye göre belirlenmiştir. Bulgular Parametrelerin referans aralıkları %90 güven aralığı ile hesaplanmıştır. Referans aralıkları IRF için %3,4–17, Ret-He için 26,9–32,8 pg, RBC-He için 25,2–30,5 pg ve delta-He için 0,5–3,7 pg olarak belirlenmiştir. Cinsiyete özel referans aralıkları Ret-He (erkek (E): 26.8–32.9 pg, kadın (K): 23.9–33.6 pg), RBC-He (E: 26.3–30.8 pg, K: 25.3–30.5 pg) ve delta-He (E: 0.5–3.7 pg, K: 0.3–3.7 pg) için hesaplanmıştır. Sonuçlar Retikülosit ve eritrosit parametreleri güvenilir, otomatize ve zahmetsiz sonuçlar sağladıkları için hastaların klinik tanı ve takibinde rahatlıkla kullanılabilir. Her laboratuvarın kullanılan cihaz ve hizmet sunulan popülasyon gibi farklılıklar göz önünde bulundurularak kendi referans aralıklarını belirlemesi önerilir.

Introduction: The current study aimed to assess the interference of in vitro haemolysis on complete blood count (CBC) using Abbott Alinity hq system, and to determine which haemolysis levels affect the reliability of sample results. Materials and methods: Blood samples obtained from 25 volunteers in K3-EDTA tubes were divided into four aliquots. The first aliquot was not subjected to any intervention. The second, third and fourth aliquots were passed through a fine needle 2, 4 and 6 times, respectively. Complete blood count was performed by multi-angle polarized scatter separation technology and haemolysis index (HI) was assessed from the plasma samples separated by centrifugation. Five groups were formed according to the HI values. The percentage biases between the results of non-haemolysed and haemolysed groups were compared with the desirable bias limits from The European Federation of Clinical Chemistry and Laboratory Medicine database and reference change values (RCVs). Results: In groups 1 to 4, the effects of haemolysis on CBC parameters were acceptable comparing to the analytical bias except for lymphocytes (7.26%-7.42%), MCH (2.59%), and MCHC (0.47%-2.81%). Results of group 5 (gross haemolysis) showed decreases in HCT(- 4.56%), RBC (- 4.07%) count and increase in lymphocyte (11.60%) count higher than the analytical performance specifications. Moreover, variations in MCH (4.65%) and MCHC (5.24%) were exceeding the RCVs. Conclusions: Gross haemolysis (haemoglobin concentration > 10 g/L) is likely to produce unreliable CBC results on non-pathological samples. Further studies including pathological specimens are needed.

Objectives Inborn errors of metabolism are generally autosomal recessive inherited disorders. The incidence and genetic features of neonatal metabolic disorders vary significantly by regions and populations. In this study, we aimed to determine the amino acid metabolism disorders and evaluate the genetic test results of these patients retrospectively. Methods The blood samples collected from heel blood and dried on filter cards in the neonatal screening program, were analyzed for amino acid metabolism disorders by (LC)-MS/MS method. Patients with suspected metabolic diseases were diagnosed with NGS method. Results Amino acid metabolism disorders were detected in 66 of 2,104 patients who were screened for suspected neonatal metabolic disorders. Sixty-two of 66 patients were diagnosed with phenylketonuria, the rest of them were diagnosed with tyrosinemia type I, arginosuccinate lyase deficiency, citrullinemia type 1 and Maple Tree syrup disease. The most common PAH gene mutations were c.1208C>T (A403V). Conclusion Phenylketonuria was the most common disease among amino acid metabolism disorders in Şanlıurfa. There were different allele frequencies compared to the PAH mutations reported in previous studies. This may be due to the different characteristics of the populations and also the high rate of consanguineous marriage in our region. Amaç Doğumsal metabolizma bozuklukları genellikle otozomal resesif geçiş gösteren hastalıklardır. Yenidoğan metabolik bozukluklarının insidansı ve genetik özellikleri bölgelere ve popülasyonlara göre önemli ölçüde değişkenlik gösterir. Bu çalışmada Şanlıurfa’da görülen amino asit metabolizması bozukluklarının belirlenmesi ve bu hastaların genetik test sonuçlarının retrospektif olarak incelenmesi amaçlandı. Gereç ve Yöntemler Yenidoğan tarama programında, topuk kanından toplanmış ve filtre kartlarında kurutulmuş kan örnekleri amino asit metabolizması bozuklukları açısından LC-MS/MS yöntemiyle analiz edildi. Metabolik hastalık şüphesi olan hastalara NGS yöntemi ile tanı konuldu. Bulgular Doğumsal metabolizma bozukluğu ön tanısı ile taranan toplam 2,104 hastanın 66’sında aminoasit metabolizma bozukluğu bulundu. 66 hastanın 62’sinde fenilketonüri tanısı, geri kalanında ise Tirozinemi tip I, Arjininosukinat liyaz eksikliği, Sitrullinemi tip 1 ve Akça Ağaç şurubu hastalığı tanısı konuldu. En sık gözlenen PAH gen mutasyon c.1208C>T (A403V) idi. Sonuç Şanlıurfa’da amino asit metabolizma bozuklukları arasında en sık görülen hastalık fenilketonüri olarak gözlendi. Sonuçlarımıza göre, önceki çalışmalarda bildirilen PAH mutasyonlarına göre farklı alel frekansları mevcuttu. Bu durum, popülasyonumuzun farklı özelliklere sahip olması ve bölgemizdeki akraba evliliği oranının yüksek olmasından kaynaklanabilir.

Introduction: Measurement of parathyroid hormone (PTH) is essential in the investigation and management of calcium metabolism disorders. To assess the significance of any assay result when clinical decision making biological variation (BV) of the measurand must be taken into consideration. The aim of the present study is determining the BV parameters for serum PTH. Materials and methods: Blood samples were taken at weekly intervals from 20 healthy subjects for ten weeks in this prospective BV study. Serum “intact PTH” concentrations were measured with electrochemiluminescence method. Biological variation parameters were estimated using the approach proposed by Fraser. Results: The values of within-subject biological variation (CVI), between-subject biological variation (CVG), analytical variation (CVA), reference change value (RCV) and individuality index (II) for serum PTH were 21.1%, 24.9%, 3.8%, 59.4% and 0.8%, respectively. Within-subject biological variation and CVG were also determined according to gender separately; 18.5% and 24.0%; 26.2% and 18.6% for male and female, respectively. Calculated desirable precision and bias goals were < 10.6% and < 6.3%, respectively. Conclusion: This study may contribute to BV data on serum PTH as it includes a sufficient number of volunteers from both genders over an acceptable period of time. We do not recommend the usage of population-based reference intervals for serum PTH concentrations. Reference change value may be helpful for the evaluation of serial serum PTH results. Nonetheless, evaluation of data according to gender is necessary when setting analytical performance specifications. © 2019, Biochemia Medica, Editorial Office. All rights reserved.

Increased urine albumin excretion is suggested to be an early marker of glomerular damage. Evaluation of a tests performance characteristics such as diagnostic sensitivity and specifictiy is a necessity before application into routine practice. To our knowledge up to now there is no study evaluating Dirui test strips for albuminuria determination. Therefore the objective of this study was to test these strips for agreement with the established method used in our routine laboratory. Freshly collected 177 urine specimens were included in the study. Strips were read on instruments Dirui H-500 and Dirui H-800 using reflectance photometry. For DiruiH13-Cr strip albumin to creatinine ratio (ACR) and for DiruiH12-800MA strip albumin determinations were compared with the analyses performed using immunoturbidimetry and kinetic Jaffe method. Sensitivity values for estimated ACR using DiruiH13-Cr strip and albumin concentration using DiruiH12-800MA strip were calculated as 80%, 72%, respectively. Specificity values were as; 71% for Dirui H13-Cr strip and 78% for Dirui H12-800MA strip. Screening tests using urine test strips should be validated before acceptance in the routine use. Dirui strips evaluated in this study seem to have a lower sensitivity than suggested and excess number of false negatives seems to limit utility of these strips. [Med-Science 2018; 7(3.000): 532-5]

WOS: 000445434700001, Aim: Biological variation (BV) of the HbA1c test can be affected by analysis method, sampling period, and disease activity. The aim of the present study was to examine the impact of CVI, CVA, and II for Tosoh G7 system. Material and Method: 96 samples from 12 healthy volunteers were collected for every two weeks during a two-month period. HbA1c levels of all samples were measured by G7 HPLC (non-porous ion-exchange) Analyser. Biological variation parameters CVI, CVA, CVG, RCV, and II were calculated. Results: The mean of HbA1c was 5.10% (32.3 mmol/mol). CVA was calculated as 2.81%. The CVI and CVG for HbA1c were 1.69% and 7.56%, respectively. RCV and II values were 9.08% and 0.22. Discussion: According to our results, the sampling period and study method were fundamental to determining biological variation parameters. When using the Tosoh G7 system, we observed similar results to other methods, e.g. boronate affinity or immunoturbidimetry. Low individuality index of HbA1 c presented that the analyte had marked individuality and that the population-based reference values had low utility for disease monitoring. Thus, estimation and inclusion of RCV in laboratory reports for HbA1c will guide the clinicians in evaluating the importance of difference between serial results and glycemic status of the patients.

Background Selection and verification of blood collection tubes is an important preanalytical issue in clinical laboratories. Today, gel tubes are commonly used with many advantages, although they are known to cause interference in immunoassay methods. In this study, we aimed to compare SSTs of two different suppliers (Ayset clot activator & Gel and Becton Dickinson (BD) Vacutainer SST II advance) with reference tubes and evaluate the effect of storage time in terms of commonly used endocrine tests such as thyroid-stimulating hormone (TSH), free thyroxine (fT4), and free triiodothyronine (fT3). Methods Fifty-five volunteers were included in the study. Samples were taken into three different tubes and analyzed for serum TSH, fT4, and fT3 on Architect ci8200 Immunoassay System. Clinical decision levels were estimated using total allowable error (TEa). Results No difference was found between tubes in terms of TSH, fT3, and fT4 levels. From a statistical standpoint, TSH and fT4 levels were no longer stable during 24, 48, and 72 hours storage time periods. However, their variations were not clinically significant. Conclusion Ayset clot activator & Gel tubes and BD Vacutainer SST II advance tubes have comparable results with glass tube in terms of TSH, fT3, and fT4 levels on Architect ci8200 Immunoassay Systems. From a clinical standpoint, serum TSH, fT4, and fT3 concentrations may be considered as stable when storing these tubes over 72 hours.

Objective:Macroprolactinemia detection is important to avoid unneccessary tests and overtreatment. High prolactin levels require routine screening and clinicians must be aware of macroprolactinemia frequency encountered with the method in use. In this study we aimed to determine the macroprolactinemia rate in our laboratory.Methods:Prolactin results of different patients analysed on two different immunoassay systems within two consecutive years were evaluated. Analyses were performed on Beckman Coulter UniCelResults:For the samples analysed on DxI800 (n=14,958) hyperprolactinemia frequency was 8.1% (n=1208). One of 138 samples submitted for macroprolactin analysis was positive, while three of them were in the gray-zone. For the samples analysed on CobasConclusion:A difference was found between two immunoassay systems used in our laboratory in terms of macroprolactinemia rate. However, inability of simultaneous analyses on both systems, lack of evaluation with gel filtration chromatography, and heterophile antibody blocking tube were the limitations.

Objectives Laboratories determine the most appropriate approach for the collection and transport of urine specimens. We investigated the effect of a chlorhexidine-based preservative tube on sample stability, compared the results of refrigerated polystyrene tubes with no additives, and investigated the effect of temperature on the performance of preservative tubes. Design and methods Fresh urine specimen (n = 48) aliquots in BD Vacutainer® Plus Urinalysis Preservative Tubes and polystyrene tubes were analyzed on an Iris Diagnostics iQ200. Samples in polystyrene tubes were refrigerated for 4 and 8 h. Four aliquots in preservative tubes were kept at room temperature for 4, 8, 24, and 72 h, while two aliquots were kept on ice for 4 and 8 h. Results There was good agreement for all chemistry and microscopy parameters with the exceptions of white blood cells (WBCs) at 24 and 72 h and red blood cells (RBCs) at 72 h. Preservative tubes on ice showed a significant decrease in concordance of WBCs and calcium oxalate (CaOx) parameters compared with the results at room temperature. Results of refrigerated polystyrene tubes showed good agreement with the exceptions of WBC clumps and amorphous crystal at 8 h. Conclusions A chlorhexidine-containing preservative tube seems advantageous for urine sample transport from outside healthcare services. A preservative tube offers comparable results with urine samples kept in a refrigerator for 4–8 h for the majority of parameters. Keeping samples at room temperature is recommended when preservative tubes are used because ice produces a negative effect on WBCs and CaOx.