How can we deal with an unexpected preoperative prolongation of the activated partial thromboplastin time (APTT)? \u2014a real world experience

Background: This article describes a tentative diagnostic algorithm for investigating patients with unexpected prolongation of activated partial thromboplastin time (APTT), detected during preoperative laboratory testing. Methods: The study population consisted of all patients undergoing preoperative laboratory testing (thus including APTT) during a 3-month period. Whenever prolonged APTT results were observed, abnormal data were investigated according to an algorithm combining familiar history of bleeding (yes/no), personal history of bleeding (yes/no) and signs/symptoms of bleeding with results of hemostasis testing, including mixing test, lupus anticoagulant (LAC) and clotting factor assays. Results: Overall, 1,433 patients underwent preoperative APTT testing throughout the 3-month study period, 76 (5.3%) of whom had prolonged values (i.e., >36.5 s). The remaining 1,357 (94.7%) patients underwent successful surgery, without further investigation. According to the algorithm, 55/76 (72.4%) of patients with prolonged APTT were excluded from supplementary laboratory testing. In the remaining 21/76 (27.6%) patients, a mixing test was scheduled. In 5/21 (23.8%) of these patients the mixing test was positive (i.e., no normalization), so that LAC testing was planned. In all these five patients LAC testing was positive. In the remaining 16/21 (76.2%) patients, mixing test was negative (i.e., normalization), so that clotting factors assays were scheduled. Seven patients were finally diagnosed with factor (F)XII deficiency, two patients with mild FXI deficiency (i.e., FXI activity of 47% and 51%), whilst 5 had clinically insignificant decreased values of one or more clotting factors and 2 patients had no identifiable explanation for APTT prolongation. The sensitivity and specificity of the algorithm for detecting clinically significant conditions (i.e., FXI deficiencies or LAC) were 1.00 and 0.99, respectively. Conclusions: The results of this study suggest that a preoperative algorithm including clinical and laboratory data may be a reasonable and sustainable approach for identifying patients at enhanced risk of perioperative bleeding or thrombosis

Academy of Emergency Medicine and Care-Society of Clinical Biochemistry and Clinical Molecular Biology consensus recommendations for clinical use of sepsis biomarkers in the emergency department.

Increasing evidence is emerging that the measurement of circulating biomarkers may be clinically useful for diagnosing and monitoring sepsis. Eight members of AcEMC (Academy of Emergency Medicine and Care) and eight members of SIBioC (Italian Society of Clinical Biochemistry and Laboratory Medicine) were identified by the two scientific societies for producing a consensus document aimed to define practical recommendations about the use of biomarkers for diagnosing of sepsis and managing antibiotic therapy in the emergency department (ED). The cumulative opinions allowed defining three grade A recommendations (i.e., highly recommended indications), entailing ordering modality (biomarkers always available on prescription), practical use (results should be interpreted according to clinical information) and test ordering defined according to biomarker kinetics. Additional grade B recommendations (i.e., potentially valuable indications) entailed general agreement that biomarkers assessment may be of clinical value in the diagnostic approach of ED patients with suspected sepsis, suggestion for combined assessment of procalcitonin (PCT) and Creactive protein (CRP), free availability of the selected biomarker(s) on prescription, adoption of diagnostic threshold prioritizing high negative predictive value, preference for more analytically sensitive techniques, along with potential clinical usefulness of measuring PCT for monitoring antibiotic treatment, with serial testing defined according to biomarker kinetics. PCT and CRP were the two biomarkers that received the largest consensus as sepsis biomarkers (grade B recommendation), and a grade B recommendation was also reached for routine assessment of blood lactate. The assessment of biomarkers other than PCT and CRP was discouraged, with exception of presepsin for which substantial uncertainty in favor or against remained

Academy of Emergency Medicine and Care-Society of Clinical Biochemistry and Clinical Molecular Biology consensus recommendations for clinical use of sepsis biomarkers in the emergency department.

Increasing evidence is emerging that the measurement of circulating biomarkers may be clinically useful for diagnosing and monitoring sepsis. Eight members of AcEMC (Academy of Emergency Medicine and Care) and eight members of SIBioC (Italian Society of Clinical Biochemistry and Laboratory Medicine) were identified by the two scientific societies for producing a consensus document aimed to define practical recommendations about the use of biomarkers for diagnosing of sepsis and managing antibiotic therapy in the emergency department (ED). The cumulative opinions allowed defining three grade A recommendations (i.e., highly recommended indications), entailing ordering modality (biomarkers always available on prescription), practical use (results should be interpreted according to clinical information) and test ordering defined according to biomarker kinetics. Additional grade B recommendations (i.e., potentially valuable indications) entailed general agreement that biomarkers assessment may be of clinical value in the diagnostic approach of ED patients with suspected sepsis, suggestion for combined assessment of procalcitonin (PCT) and Creactive protein (CRP), free availability of the selected biomarker(s) on prescription, adoption of diagnostic threshold prioritizing high negative predictive value, preference for more analytically sensitive techniques, along with potential clinical usefulness of measuring PCT for monitoring antibiotic treatment, with serial testing defined according to biomarker kinetics. PCT and CRP were the two biomarkers that received the largest consensus as sepsis biomarkers (grade B recommendation), and a grade B recommendation was also reached for routine assessment of blood lactate. The assessment of biomarkers other than PCT and CRP was discouraged, with exception of presepsin for which substantial uncertainty in favor or against remained

Clinical usefulness of automated cellular analysis of synovial fluids: a paradigmatic case report for diagnosing peri-prosthetic infections

We describe here the case of an 18 years old male patient who underwent osteosynthesis surgery with a plate and screws for multi-fragment fracture of his right femur, in December 2000. The patient developed a series of complications up to May 2017, when he was readmitted with severe functional impairment and inability to walk without crutches. Physical examination revealed erythema, swelling at surgical site and leakage of pus from sinus-tract. An arthrocentesis was hence performed, followed by white blood cell count and differential in synovial fluid with Sysmex XN 2000 body fluid mode. The final leukocyte count was 38 7109/L, with 95% polymorphonuclear leukocytes (PMN), thus compatible with peri-prosthetic infection. The patient underwent additional surgery to remove the knee replacement, accurate debridement and antibiotic impregnated static cement spacer implantation. Three months after surgery, the patient was readmitted for removing the spacer, replaced by a new static device. In May 2018, surgical debridement and removal of the spacer was scheduled with resection arthroplasty. In November 2018 the patient presented again a sinus tract, and underwent another arthrocentesis for physical and microbiological examination of synovial fluid. The leukocyte count in the synovial fluid was again performed with Sysmex XN 2000 body fluid mode, and revealed the presence of 44.5 7109/L cells, with 90% PMN. The synovial fluid was positive for Van-A Enterococcus faecalis, so that right hip disarticulation was urgently planned. In conclusions, this case provides clear evidence that automated leukocyte count and differential in synovial fluid shall now be considered an unavoidable part of the diagnostic approach to patients with suspected peri-prosthetic infections

Folati sierici vs folati intraeritrocitari: quale parametro e piu sensibile nel predirre la carenza nei pazienti emodializzati?

Folati sierici vs folati intraeritrocitari: quale parametro è più sensibile nel predirre la carenza nei pazienti emodializzati? Scopo del lavoro e materiali e metodi L’anemia iporigenerativa è tipica nell’insufficienza renale cronica e la carenza di acido folico può essere una delle determinanti. Per individuare quali pazienti necessitassero della supplementazione di acido folico abbiamo determinato i folati intraeritrocitari (FIE), i folati sierici (FS), la vitamina B12 (B12) e l’omocisteina (HCY) in 29 pazienti emodializzati, a 12 e 24 mesi (T12 e T24) dall’interruzione della supplementazione endovenosa settimanale con Calcio Levofolinato e Cianocobalamina. La determinazione dei folati sierici, eritrocitari e vitamina B12 è stata effettuata con il sistema Access II Beckman Coulter con metodica CLIA; quella dell’HCY con metodica immunoturbidimetrica su AU480 Olympus Beckman. Il valore di folato intraeritrocitario è stato calcolato correggendolo per il valore dell'ematocrito. Risultati I livelli di B12 si sono ridotti del 97% pur mantenendosi tutti al di sopra dei limiti di normalità. Analogamente si è evidenziata, dopo sospensione della supplementazione, una riduzione significativa del FIE, con una riduzione netta del 94%, (t di Student per dati accoppiati p237 ng/ml) mentre ben l’83% dei pazienti al T12 e al T24 mostravano valori di FS inferiori ai limiti della norma (>5,21 ng/ml). Come descritto in letteratura, anche nella nostra esperienza, il FS sembra essere più sensibile, rispetto al FIE, nell’evidenziare deficit di folati in soggetti non sottoposti a supplementazione e risulta facilmente correlabile all’omocisteina. Per contro, i folati intraeritrocitari più tardivamente rilevano l’instaurarsi di un deficit, oltre ad essere soggetti a maggiori variabili preanalitiche dovute al trattamento del campione. Conclusioni In accordo con i dati della letteratura, pertanto, pur nell’esiguità del campione, ma dopo un follow-up di 24 mesi, il folato sierico potrebbe rappresentare un marker più precoce e predittivo, rispetto al FIE, del reale deficit di folati nel paziente uremico in emodialisi. Bibliografia C.L. Farrell , S. H. Kirsch and M. Herrmann “Red cell or serum folate: what to do in clinical practice?” Clin Chem Lab Med 2013; 51(3): 555-569

Glucose variation in centrifuged serum and lithium-heparin gel tubes stored for up to 96\u2009hours at room temperature or 4\u2009\ub0C

This study aimed to verify glucose stability within centrifuged serum and lithium-heparin tubes stored at room temperature (RT) or 4\u2009\ub0C. Sixty paired serum (plus gel separator), lithium-heparin (plus gel separator) and K2-EDTA tubes were centrifuged within 30\u2009min from collection. Thirty serum and lithium-heparin tubes were then stored at RT, whilst the other 30 serum and lithium-heparin tubes were kept at 4\u2009\ub0C. Complete cell blood count was performed in serum and plasma after centrifugation, as well as in K2-EDTA paired whole blood tubes. Glucose was measured immediately after centrifugation and 3, 6, 24, 48, 72 and 96\u2009h afterwards. Immeasurable blood cells values were found in serum, whilst residual leukocytes and platelets were present in lithium-heparin plasma. Regardless of storage conditions, glucose concentration decreased 3\u2009h after centrifugation in lithium-heparin tubes, displaying uninterrupted reduction until 96\u2009h. Mean decrease per hour was higher in plasma tubes stored at RT than at 4\u2009\ub0C. Performance specification was exceeded between 6 and 24\u2009h of storage in most plasma tubes. Glucose concentration significantly decreased in serum tubes between 24 and 48\u2009h, regardless of storage conditions. The mean glucose variation never exceeded performance specification throughout the study period. Mean glucose decrease per hour in plasma was not associated with blood cells counts before and after centrifugation, and was probably attributable to the presence of blood cells entrapped within the gel. Delayed glucose measurement in centrifuged serum tubes may be clinically viable up to 96\u2009h, whilst it may be unadvisable in centrifuged lithium-heparin tubes

Routine coagulation testing in Vacutainer\uae Citrate Plus tubes filled at minimum or optimal volume

Background Filling of citrate tubes with appropriate amount of blood is essential for obtaining reliable results of coagulation testing. This study aimed to verify whether results of routine coagulation tests are comparable when the new Becton Dickinson Vacutainer\uae Citrate Plus tubes are filled at minimum or optimal volume. Methods The study population consisted of 133 patients (40 on oral anticoagulant therapy), who had blood collected for routine coagulation testing. Two sequential Vacutainer\uae Citrate Plus tubes of the same type and lot were drawn. The first tube was collected after a butterfly needle was inserted into the vein, so that the air in the tubing was aspirated into the tube before blood (minimum fill volume), whilst the second was drawn at optimal fill volume. Experiments were repeated using 2.7-mL (n\u2009=\u200986) and 1.8-mL (n\u2009=\u200947) tubes. Results Prothrombin time (PT) and fibrinogen values were slightly but significantly decreased in tubes with minimum than in those with optimal fill volume. The activated partial thromboplastin time (APTT) was slightly prolonged in tubes with minimum than in those with optimal fill volume, but the difference was not statistically significant. An identical trend was noted in separate analyses for the 2.7-mL and 1.8-mL tubes. Spearman's correlations between the two fill volumes were always >0.94 and bias was always within the quality specifications. Conclusions Blood drawing into Vacutainer\uae Citrate Plus tubes at minimum fill volume does not clinically bias routine coagulation testing

Serum prevalence of anti-SARS-CoV-2 antibody in a population of health care and administrative workers in a hospital in Tuscany (Italy).

Introduction: the challenges due to COVID-19 pandemic forced scientific community to focus their efforts to improve diagnosis and management of patients. The recognized gold standard for the diagnosis is the reverse transcription polymerase chain reaction (RT-PCR) on orofaringeal and nasal swabs. Recently, the antibody detection surge to attention with the aim of estimating the epidemiological impact of the pandemic. Methods: the Screen Test COVID-19 2019-nCov IgG/IgM (Screen Italia, Perugia, Italy) an immunochromatographic lateral flow test has been used to assess the immunological status of 356 asymptomatic healthcare and administrative workers of our hospital. Results: only 26 (7.3%) of the screened subjects was positive for IgM and/or IgG anti SARS-CoV-2 virus although the beginning of the epidemic in Tuscany can be dated two months before. The RT-PCR performed on these samples revealed that only 5 (19%) of them were positive for viral RNA on orofaringeal swab. Conclusions: antibody detection will be of great value in the near future to assess global pandemic impact on population and to drive health policy for the lock down release

Analytical Evaluation of a Vancomycin Immunoassay in Synovial Fluid

In clinical laboratories performing routine activities, the need to answer the burning clinical question in emerging field may be limited by lack of technology support or assays accessibility. Commercially available methods, although originally validated for specific biological matrices, may be employed for other matrices, following appropriate guidelines such as Clinical and Laboratory Standards Institute (CLSI) EP 19. We investigated the use of a vancomycin assay with synovial fluid samples, in view of a possible employment in vancomycin release study. The standard of care of periprosthetic joint infection is a two- stage revision surgery with antibiotic-loaded bone cement implantation. Vancomycin, for its activity against gram-positive bacteria even multidrug-resistant staphylococci, is the most widely used antibiotic. Despite the widespread use of such devices, little is known about the in vivo elution in the joint space. Clinical laboratories equipped with a validated, affordable method to quantify vancomycin in synovial fluid, may support clinical research, and give an important contribution to the study of the pharmacokinetics of antibiotic release from bone cement matrix