Biological variation of peripheral blood T-lymphocytes.

BACKGROUND: Flow cytometric analysis of the lymphocyte subsets has become one of the most commonly used techniques in the routine clinical laboratory. It is frequently used in monitoring lymphocyte recovery after hematopoietic stem cell transplantation (HSCT), as well as diagnosis and treatment of acquired immunodeficiency syndrome (AIDS). Reliable biological variation (BV) data is needed for safe clinical application of these tests. In this study, similar preanalytical and analytical protocols to the European Federation of Clinical Chemistry and Laboratory Medicine (EFLM) checklist were followed and a stringent statistical approach was applied to define BV of T-lymphocytes. METHODS: During the 10 weeks study period, weekly blood samples were obtained from 30 healthy individuals (20 females, 10 males) and analyzed with Facs Canto (BD Biosciences, San Jose, CA, USA) analyzer using 4-colour BD Multitest CD3/CD8/CD45/CD4 reagents. Data were assessed in terms of normality, tendencies, outliers and variance homogeneity prior to applying coefficient of variance (CV)- analysis of variance (ANOVA) test. Sex-stratified within-individual (CVI) and between-individual (CVG) BV estimates of CD3+, CD3 + CD4+, CD3 + CD8+, and CD3 + CD4 + CD8+ T lymphocytes were calculated. RESULTS: No difference was found between males and females. Except for the CD3 + CD4 + CD8+ subset, stable BV was found for CD3+, CD3 + CD4+, and CD3 + CD8+ subsets. CONCLUSSION: Instead of using the conventional reference ranges of CD3+, CD3 + CD4+ and CD3 + CD8+ counts for monitoring HIV positive or post-HSCT patients, RCV should be used. Because individualityis characteristic of lymphocytes subsets RCVs should be used instead of RIs for patient monitoring.

Serum soluble fas ligand levels in familial Mediterranean fever.

INTRODUCTION: Fas/FasL system plays an important role in the regulation of cell life and death, and circulating levels of sFasL have been shown to increase in some inflammatory conditions. However, there is no sufficient information about the levels of sFasL in patients with FMF. This study was designed to evaluate the serum sFasL levels in patients with FMF during attack and attack-free periods. METHODS: Twenty-five FMF patients in attack and forty-four in free-attack period, and 20 age-, sex-, and BMI-matched healthy controls were included in this study. Participants with any chronic diseases were excluded. Blood samples were obtained within the first 24 h of the attack period and between febrile attacks, and levels of WBC, ESR, Fibrinogen, hsCRP and sFasL were determined. RESULTS: The levels of traditional acute phase reactants during the attack were significantly higher than the attack-free and controls (p < 0.05). The serum sFasL levels in the FMF study groups did not differ from the control group (0.70 ± 0.08 vs. 0.73 ± 0.12; 0.70 ± 0.08 vs. 0.83 ± 0.14; 0.73 ± 0.12 vs. 0.83 ± 0.14, respectively, p > 0.05). Moreover, the sFasL levels during the attack were not significantly different from those in attack-free patients (0.70 ± 0.08 vs. 0.83 ± 0.14, p > 0.05). CONCLUSION: In this study, we demonstrated that serum sFasL levels were not markedly affected in FMF and cannot be used as a supportive marker to differentiate attacks from attack-free periods. However, further studies are needed to determine its usefulness as a marker in clinical practice.

The effects of N-acetylcysteine on testicular damage in experimental testicular ischemia/reperfusion injury.

PURPOSE: The aim of this study to evaluate the effects of N-acetylcysteine (NAC) on testicular damage in a rat testicular ischemia-reperfusion (I/R) injury model. METHODS: Thirty male Wistar albino rats were divided into five groups. Group 1: sham control, Group 2: torsion (T), Group 3: torsion/detorsion (T/D), Group 4: the early NAC treatment plus T/D, 20 mg/kg of NAC was given intravenously 60 min before detorsion; Group 5: the late NAC treatment plus T/D, 20 mg/kg of NAC was given intravenously 5 min before detorsion. After torsion (2 h) and detorsion (2 h), bilateral orchiectomies were performed to determine the tissue levels of malondialdehyde (MDA) or more exactly thiobarbituric acid reactive substance (TBARS), myeloperoxidase activity and histopathological changes. RESULTS: The most significant increase in the mean TBARS level and decrease in the mean seminiferous tubular diameter, germinal epithelial cell thickness values in bilateral testes were observed in T/D group rather than other groups. TBARS levels of early NAC treatment group were significantly lowered and histological parameters of spermatogenesis were significantly improved in bilateral testes when compared with T and T/D groups. CONCLUSION: Our results suggest that the early administration of NAC may have a protective effect in the rat experimental testicular T/D models.

Tumor marker requests in a general teaching Turkish hospital.

Serum tumor markers may be requested inappropriately by clinicians. In this retrospective study, we aimed to investigate the appropriateness of TM requests in our hospital. Patients in the study were identified from the TM requests for 3 months between June-August 2004, using the laboratory database. A total of 2249 patients (1351 men, 898 women) were included in the study and there were 6570 TM requests. The number of requests were 1050 (16%) for Carbohydrate Antigen 19-9, 993 (15.1%) for Cancer Antigen 125, 941 (14.3%) for Prostate Specific Antigen, 921 (14%) for free PSA, 925 (14.1%) for Cancer Antigen 15-3, 788 (12%) for Alphafetoprotein, 730 (11.1%) for Carcinoembryonic Antigen and 222 (3.4%) for AFP/Human Chorionic Gonadotrophin. Our findings support the idea that for the evidence-based use of TM requests the education of clinical staff is required. Clear clinical guidelines including recommendations about the appropriate use of TM can be useful for this education process. Careful audit studies are also useful to determine the impact of these guidelines on the practice of evidence-based laboratory medicine.