Transportation and handling of blood samples prior to ammonia measurement in the real life of a large university hospital.

Background: Hyperammonemia is neurotoxic and as such can be a medical emergency. Preanalytical factors greatly influence the blood ammonia concentration results.

Aims And Methods: Ammonia concentrations measured in the real life setting of a large hospital after pneumatic transport of blood samples and various time periods before centrifugation were compared to those based on the indications of the reagent manufacturer.

Wide-range CRP versus high-sensitivity CRP on Roche analyzers: focus on low-grade inflammation ranges and high-sensitivity cardiac troponin T levels.

Wide-range C-reactive protein (wr-CRP) has been proposed as an economical alternative to high-sensitivity C-reactive protein (hs-CRP) for the evaluation of low-grade inflammation-associated cardiovascular risk (LGI-CVR). Concomitant values of serum hs-CRP and plasma wr-CRP ≤5 mg/L, and high-sensitivity cardiac troponin T (hs-cTnT), all assayed on Roche Diagnostics analyzers over a 1.8-year period, were extracted from a hospital laboratory database.

Plasma cystatin C as a marker for estimated glomerular filtration rate assessment in HIV-1-infected patients treated with dolutegravir-based ART.

Objectives: Inhibition of the organic cation transporter-2 renal tubule transporter by dolutegravir leads to serum creatinine increase. Serum cystatin C is a non-organic cation transporter-2-dependent marker, possibly enabling glomerular filtration rate (GFR) estimation under dolutegravir. Our goal was to evaluate the changes in creatinine- and cystatin C-based estimated GFR values before and after dolutegravir initiation.

High-Sensitivity Cardiac Troponin T: a Preanalytical Evaluation.

Background: Little is known about the effects of preanalytical conditions on high-sensitivity cardiac troponin T (hs-cTnT) concentrations.

Methods: Variations of hs-cTnT concentrations were evaluated under the following preanalytical conditions: 1) serum vs. lithium-heparin (Li-Hep) plasma, with or without separator gel; 2) centrifugation time (15-minutes vs.

Stability of Routine Biochemical Analytes in Whole Blood and Plasma From Lithium Heparin Gel Tubes During 6-hr Storage.

Background: The stability of biochemical analytes has already been investigated, but results strongly differ depending on parameters, methodologies, and sample storage times. We investigated the stability for many biochemical parameters after different storage times of both whole blood and plasma, in order to define acceptable pre- and postcentrifugation delays in hospital laboratories.

Methods: Twenty-four analytes were measured (Modular® Roche analyzer) in plasma obtained from blood collected into lithium heparin gel tubes, after 2-6 hr of storage at room temperature either before (n = 28: stability in whole blood) or after (n = 21: stability in plasma) centrifugation.

Hemolysis indexes for biochemical tests and immunoassays on Roche analyzers: determination of allowable interference limits according to different calculation methods.

Objectives: To determine the hemolysis interference on biochemical tests and immunoassays performed on Roche Diagnostics analyzers, according to different maximum allowable limits.

Design And Methods: Heparinized plasma and serum pools, free of interferences, were overloaded by increasing amounts of a hemoglobin-titrated hemolysate. This interference was evaluated for 45 analytes using Modular(®) and Cobas(®) analyzers.

Lipoprotein-associated phospholipase A2 during the hyperacute stage of ischemic and hemorrhagic strokes.

Background: The objectives of the study were to compare lipoprotein-associated phospholipase A2 (Lp-PLA2) levels in a prospective cohort including both ischemic and hemorrhagic strokes at the hyperacute phase, and to investigate if these levels were associated with stroke severity.

Materials And Methods: Lp-PLA2 mass and activity were measured during the first 6 hours of symptom onset before any therapeutic intervention. The Lp-PLA2 level was analyzed by comparing the mass and activities in ischemic strokes and spontaneous intracerebral hemorrhages (ICH).