BACKGROUND Clinical Chemistry is the backbone of medical treatment, diagnostics, and prevention. The laborato-ries are trying to improve the quality and to reduce diagnostic errors and processing time and safeguard trace-ability of all laboratory procedures to ensure patient safety. Six sigma belongs to statistical quality control and provides a new methodology for measuring and improving process performance in laboratory. METHODS Activities of AST, ALT, CK, LDH, Amy, and γ-GT were determined by standard kinetic methods on a Vitros 5600 biochemistry analyzer. Two daily quality controls (Verifier I and Verifier II) were run over 60 days. Total percent CV was calculated from routine daily QC. Between-instrument bias was also calculated from daily QC. RESULTS The calculated sigma metrics for AST were 6.9 and 3.8; for ALT 9.3 and 5.6; for CK 6.6 and 5.3; LDH 5.2 and 5.2; for γ-GT 4.9 and 2.7; and for amylase 8.7 and 7.1. Analytical performance for AST, ALT, CK, LDH, and Amylase is world class. On the other hand, γ-GT analytical performance is poor. CONCLUSIONS Six Sigma benefits from earlier quality management approaches that creates new challenges for medical laboratories.

Background: The serum prostate specific antigen for the early detection and screening for prostate cancer are very common used among physicians as the best screening tool for prostate cancer. The result of prostate specific antigen levels discriminates whether or not a prostate biopsy should be performed. The lack of specificity is a limitation of PSA as tumor marker, increased PSA concentrations are found not only in patients with prostate cancer but also in patients with benign prostatic disease. The object of this study was to improve the specificity and sensitivity of prostatic cancer detection. We evaluated total PSA levels, free PSA levels and the prostate volume in asymptomatic patients which came for routine check without medical history of prostate cancer. Methods: We received medical record of 90 patients between 50-60 years. Total and free PSA in serum was measured with the analyzer Architeckt i2000 SR. Prostate volume was determined by transrectal ultrasound. Results : The ratio of total and free PSA levels to prostate volume was significantly (p < 0.001) between all three groups. It was observed that increased prostate volume correlates with increased level of total and free PSA in serum. Conclusion: Early studies have demonstrated the advantage of measuring prostate volume with PSA total and free levels in serum as a useful tool for early diagnosis of prostate cancer. Data from this study on 90 patients with total PSA in the range from 0,22-7,0 ng/ml confirmed the well known correlation. All three parameters total PSA, free PSA and prostate volume showed significant correlation and a useful tool in prediction of prostate cancer for Bosnia and Herzegovina men.

Introduction: Glycated hemoglobin (HbA1c) is formed by non-enzymatic binding of glucose to the free amino group of the N-terminal end of the s-chain of hemoglobin A. HbA1c is representative of the mean blood glucose level over three months. The aim of the study was to evaluate the Hemoglobin A1c immunoturbidimetric assay performance on two different commercial systems.Methods: We evaluated the precision and trueness for determination of HbA1c in whole blood. Concentrations of total hemoglobin and HbA1c were evaluated on Dimension Xpand (Siemens) and Cobas 501 (Roche) analyzers. HbA1c was measured in a latex agglutination inhibition test. Commercial controls Liquichek Diabetes Control Level 1 and Liquichek Diabetes Control Level 2 (Bio Rad) at two levels were used for quality control. Analytical validation of HbA1c included: within-run imprecision, between-day imprecision, inaccuracy and comparison determination on the human samples on 2 systems: Dimension Xpand and Cobas 501 analyzers. Results: Within-run imprecision on the commercially controls for Level 1 is 4.5% and Level 2 is 3.2% between-day imprecision on commercially controls is 6.1% Level 1 and 5.1% Level 2 for respectively inac- curacy on commercially controls for Level 1 is 1.8% and Level 2 is 4.8%. Method comparison on human samples shows the correlation coefficient of 0.99.Conclusion: The presented results of the analytical evaluation methods for the determination of HbA1c showed an acceptable accuracy and precision.

Introduction: Whey-acidic protein human epididymis protein 4 (HE4) is a new promising biomarker for epithelial ovarian cancer. The measured HE4 values may depend on the testing procedure used. The aim of this study was to evaluate the Methods : We evaluated a HE4 method on Elecsys 2010 analyzer. The method for quantitative determination of HE4 is direct, competitive chemiluminescent immunoassay. For quality control we use Elecsys PreciControl HE4 1 and 2. HE4 was measure on sera obtained from 56 women ( 20 healthy and 36 with epithelial ovarian cancer). Results: The Roche HE4 assays showed a good linearity (r=0.99) and precision (intrassayed total CV<5%). The median HE4 serum concentrations was significantly higher among EOC patients than healthy females (p<0,05). Elevated levels HE4 were found in 78 % patients with epithelial ovarian cancer. Conclusions : The presented results of the analytical evaluation methods for the determination of HE4 on the Elecsys 2010 analyzer showed an acceptable accuracy and precision.

Helminth parasites that inhabit mammalian body surfaces have a highly evolved relationship with the immune system. Many of these resident helminths carry out functions to ensure their survival in the hosts. To attain this objective helminth parasites adopt immunoregulatory mechanisms to counter host’s hostile immune response. Indeed, immunomodulatory molecules have been discovered in the worm’s extracts and in their excretion/secretion. In this review, we discuss the state of our understanding of the interplay between helminths and immune pathways. We also highlight the key challenges that must be confronted in identification of the helminth-derived molecules involved in immune modulation.  We consider whether helminth-derived signaling hold promise for the design of novel therapeutic approaches for the treatment of inflammatory disorders (inflammatory bowel disease, allergies, and autoimmune diseases).

Introduction: Low sensitivity and specificity in traditional laboratory tests became insufficient for accurate diagnostics and initiation of proper treatment of patients infected with bacterial meningitis. High sensitivity Creactive protein (hsCRP) may be an appropriate supplement for rapid diagnosis of bacterial meningitis. The subject of our investigation was the determination of C- reactive protein in cerebrospinal fluid (CSF) during acute bacterial meningitis. Methods: HsCRP was analysed by a sensitive immunoturbidimetric assay using the Dimension RxL analyser (Siemens). Cerebrospinal fluid concentrations of C-reactive protein have been measured in 20 patients (age range,1 to 50 years) presenting with acute bacterial meningitis and also in a non-infected, non-inflamed control group (n=25). Results: The accuracy and precision of the method proved to be satisfactory. Repeatability of serial sampling for hsCRP described by coefficient of variation were CV=2.1-4.5%. This assay hsCRP in cerebrospinal fluid demonstrates adequate performance characteristics for routine clinical use. Elevated levels of CRP were found in 95% patients with bacterial meningitis. The mean CRP value in 25 uninfected control group was 0.25 mg/L (range 0.10-0.55). The mean CRP for patients with bacterial meningitis was 21.4 mg/L (range 0.40-100). Conclusions: A sensitive assay for CRP in CSF would be an useful adjunct to conventional investigation of acute infective meningitis.