Laboratory testing of extravascular body fluids: National recommendations on behalf of the Croatian Society of Medical Biochemistry and Laboratory Medicine. Part II - Synovial fluid.

Joint diseases are conditions with an often progressive and generally painful nature affecting the patient's quality of life and, in some cases, requiring a prompt diagnosis in order to start the treatment urgently. Synovial fluid (SF) laboratory testing is an important part of a diagnostic evaluation of patients with joint diseases. Laboratory testing of SF can provide valuable information in establishing the diagnosis, be a part of a patient's follow-up and treatment with the purpose of improving the patient's health and quality of life. Synovial fluid laboratory testing is rarely performed in Croatian medical biochemistry laboratories. Consequently, procedures for SF laboratory testing are poorly harmonized. This document is the second in the series of recommendations prepared by the members of the Working group for extravascular body fluid samples of the Croatian Society of Medical Biochemistry and Laboratory Medicine. It addresses preanalytical, analytical, and postanalytical issues and the clinical significance of tests used in SF laboratory testing with the aim of improving the value of SF laboratory testing in the diagnosis of joint diseases and assisting in the achievement of national harmonization. It is intended for laboratory professionals and all medical personnel involved in synovial fluid collection and testing.

Simple thrombin-based method for eliminating fibrinogen interference in serum protein electrophoresis of haemodialysed patients.

INTRODUCTION: Serum samples of haemodialysed patients collected through vascular access devices, e.g. central venous catheter (CVC) can contain residual heparin, which can cause incomplete clotting and consequently fibrinogen interference in serum protein electrophoresis (SPE). We hypothesized that this problem may be overcome by addition of thrombin and aimed to find a simple thrombin-based method for fibrinogen interference removal. MATERIALS AND METHODS: Blood samples of 51 haemodialysed patients with CVC were drawn through catheter into Clot Activator Tube (CAT) and Rapid Serum Tube Thrombin (RST) vacutainers (Becton Dickinson, New Jersey, USA) following the routine hospital protocols and analysed with gel-electrophoresis (Sebia, Lisses, France). Samples were redrawn in the CAT tubes and re-analysed after being treated with thrombin using two methods: transferring CAT serum into RST vacutainer and treatment of CAT serum with fibrinogen reagent (Multifibren U, Siemens, Marburg, Germany). RESULTS: Direct blood collection in RST proved to be slightly more efficient than CAT in removing the interfering band in beta fraction (CAT removed 6/51 and RST removed 12/51, P = 0.031). Transferring CAT serum into the RST vacutainer proved to be more efficient for subsequent removal of interfering band from CAT serum than the addition of fibrinogen reagent (39/45 vs. 0/45 samples with efficiently removed interfering band, P < 0.001). CONCLUSION: Fibrinogen interference caused by incomplete clotting because of residual heparin can be overcome by addition of thrombin. Transferring CAT serum into the RST vacutainer was the most efficient method.

Laboratory testing of extravascular body fluids: National recommendations on behalf of the Croatian Society of Medical Biochemistry and Laboratory Medicine. Part I - Serous fluids.

Extravascular body fluids (EBF) analysis can provide useful information in the differential diagnosis of conditions that caused their accumulation. Their unique nature and particular requirements accompanying EBF analysis need to be recognized in order to minimize possible negative implications on patient safety. This recommendation was prepared by the members of the Working group for extravascular body fluid samples (WG EBFS). It is designed to address the total testing process and clinical significance of tests used in EBF analysis. The recommendation begins with a chapter addressing validation of methods used in EBF analysis, and continues with specific recommendations for serous fluids analysis. It is organized in sections referring to the preanalytical, analytical and postanalytical phase with specific recommendations presented in boxes. Its main goal is to assist in the attainment of national harmonization of serous fluid analysis and ultimately improve patient safety and healthcare outcomes. This recommendation is intended to all laboratory professionals performing EBF analysis and healthcare professionals involved in EBF collection and processing. Cytological and microbiological evaluations of EBF are beyond the scope of this document.

Laboratory testing of extravascular body fluids in Croatia: a survey of the Working group for extravascular body fluids of the Croatian Society of Medical Biochemistry and Laboratory Medicine.

INTRODUCTION: We hypothesized that extravascular body fluid (EBF) analysis in Croatia is not harmonized and aimed to investigate preanalytical, analytical and postanalytical procedures used in EBF analysis in order to identify key aspects that should be addressed in future harmonization attempts. MATERIALS AND METHODS: An anonymous online survey created to explore laboratory testing of EBF was sent to secondary, tertiary and private health care Medical Biochemistry Laboratories (MBLs) in Croatia. Statements were designed to address preanalytical, analytical and postanalytical procedures of cerebrospinal, pleural, peritoneal (ascites), pericardial, seminal, synovial, amniotic fluid and sweat. Participants were asked to declare the strength of agreement with proposed statements using a Likert scale. Mean scores for corresponding separate statements divided according to health care setting were calculated and compared. RESULTS: The survey response rate was 0.64 (58 / 90). None of the participating private MBLs declared to analyse EBF. We report a mean score of 3.45 obtained for all statements evaluated. Deviations from desirable procedures were demonstrated in all EBF testing phases. Minor differences in procedures used for EBF analysis comparing secondary and tertiary health care MBLs were found. The lowest scores were obtained for statements regarding quality control procedures in EBF analysis, participation in proficiency testing programmes and provision of interpretative comments on EBF's test reports. CONCLUSIONS: Although good laboratory EBF practice is present in Croatia, procedures for EBF analysis should be further harmonized to improve the quality of EBF testing and patient safety.