Annales de biologie clinique最新文献

It is important that a clinical laboratory has implemented appropriate procedures for quality control, which includes both internal quality control (IQC) and external quality assessment (EQA) with the common goal to detect systematic errors and random errors. It is the case for both the Hemohub® Bayesian tools for IQC results interpretation and the ECAT EQA optimised bivariate z-scores analysis. On a concrete case study, we demonstrate both the higher sensitivity and specificity of optimised bivariate z-scores analysis than the univariate approach. The Bayesian IQC results interpretation like the ECAT analysis confirmed the explicit conclusion i.e. an increase of the random error corresponding to the increase of the inter assay coefficient of variation (CV) at the date of EQA samples runs. Improvement of repaired dysfunction could be then daily observed on IQC results and then confirmed on EQA results thanks to the complementarity of the two approaches.

Anti-Jo1 antibodies are usually known markers of myositis. However, they can be associated with different pathologies. We aimed to determine the immuno-clinical characteristics of patients with positive anti-Jo1. We enrolled 31 anti-Jo1 positive patients, selected from 10429 cases tested for antinuclear antibodies (ANA) by indirect immunofluorescence. The anti-Jo1 identification was motivated by the ANA pattern or the clinical data of patients. The average age of patients was 36.9 ± 10 years (F/M sex ratio: 3.4). The overall prevalence of anti-Jo1 was 0.3% among all ANA-tested cases. The ANA pattern associated with the presence of anti-Jo1 was heterogeneous with ANA negative in 38.7 % of cases. They were associated with different autoantibody specificities in 64.5 % of cases and were alone in 35.5% of cases. When confronted with clinical data, anti-Jo1 positivity was associated with autoimmune (77,4%) and non-autoimmune (22,6%) clinical conditions. Our study shows a low overall prevalence of anti-Jo1. These antibodies must be systematically tested for in the context of myositis even if ANA is negative. Nevertheless, their positivity in other systemic or even non-autoimmune diseases requires further studies to better understand their clinical significance.

The diagnosis of subarachnoid hemorrhage (SAH) is extremely important for appropriate management. Cerebral computed tomography (CT), used as the first-line investigation to detect bleeding, has excellent sensitivity if performed promptly, but its sensitivity falls sharply with the time elapsed since the onset of SAH. Oxyhemoglobin and bilirubin, the breakdown products of heme, are detectable in cerebrospinal fluid (CSF) by spectrophotometric absorption, which defines the search for xanthochromia pigment in CSF. Both parameters can be sought when imaging is negative or doubtful with a strong suspicion of SAH based on clinical signs. In this context, our working group at the Société Française de Biologie Clinique (SFBC) is proposing recommendations to provide medical biologists with support for the implementation and validation of "oxyhemoglobin and bilirubin in CSF" test and enabling them to play their part in the diagnostic process. From the pre-analytical stages through to the delivery of results, we will summarize the pitfalls to be avoided, the main decision values and different physiological and pathological profiles.

The relevant and correct prescribing of medical biology is a major public health issue. Correct prescribing is a legal obligation under article L6211-8 of the French Public Health Code and is an integral part of the biologist's daily work, already specified in the 2012 (section 4.7) and 2022 (section 5.3.3) versions of the NF EN ISO 15189 standard. COFRAC document SH REF 02 v08 specifies the requirements for consultancy services. The adaptation of the prescriptions is a revision of the contract with the prescriber, which makes it possible to optimize patient care and ensure the satisfaction of the laboratory users. Although essential, accurate prescribing is time consuming. "Chronophage" is the term that has been used for almost a decade. At present, the work of biologists in this area is not valued. In fact, there is no evaluation system to highlight this regulation control activity. To date, no work has been published to estimate this time, this chronophagy, and to evaluate its impact. Cost measurement using Time-Driven Activity-Based Costing (TDABC), a variant of Activity-Based Costing (ABC), is based on a process approach. The main contribution of TDABC is that it uses a single cost driver: time. Serum immunofixation is a test used to confirm and monitor plasma cell dyscrasias, the archetype of which is multiple myeloma. The learned societies and the IMWG provide explicit diagnostic criteria, but the guidelines do not address the frequency of follow-up. In particular, the frequency of repeat and follow-up serum immunofixation remains unaddressed from an evidence-based medicine perspective. This work has made it possible to highlight the savings made between 1st January and 31th August 2023 thanks to the involvement of the biologist and to highlight his essential role in the process of controlling the overall expenditure (reagents, human resources, time and money) in the specialized biochemistry sector (bench: proteins) and to strengthen the role of the biologist within the institution. The various players in the healthcare sector - prescribing physicians, biologists, hospital administrators and, last but not least, patients - all have an essential role to play in maximizing value for patients and in the healthcare economy.

Detection of schistocytes is an important first step in the differential diagnosis of thrombotic microangiopathy. It is however labor intensive and prone to subjectivity. To improve and standardize the detection and quantification of schistocytes, we studied its automated analysis by digital microscopy DM1200 (CellaVision®) on 63 positive and 102 negative smears obtained from SP-50 (Sysmex®). Easy to use and very useful for staff training, it showed a lower between-observer coefficient of variation than usually described for manual counting (25% vs. 50%). Very sensitive (100%) in pre-classification, the detection of schistocytes was highly sensitive (98.4%) and specific (96.8%) after reclassification (AUCROC = 0.9929), showing a good correlation with manual microscopy. TAT was comparable to manual counting. For positive smears, the percentage of schistocytes was similar between pre- and post-classification. However, 29.6% of pre-classified schistocytes were removed and 21.8% were added. For negative smears a significative overestimation of schistocytes (292%) was observed. Except poikilocytosis, on negative smears, the most common error of the software (24.9%) was due to platelets classified in schistocytes. Were also observed for example erroneous divisions of the image (3.2%) or artifactual schistocytes resulting from scratches in the smear (2.6%). Another limit is the high number of red blood cells not analyzed (46.8% for high-density smears), which might false the schistocytes percentage. To conclude, CellaVision® technology showed many benefits, but also limits that the operator needs to know.

Tuberculosis remains one of the leading causes of mortality worldwide. Microscopy and culture still the references of Tuberculosis diagnosis. Microscopy has a low sensitivity, specificity and culture is time consuming. For this reason, rapid and reliable diagnosis of the disease is required. We describe a retrospective comparison study of tuberculosis diagnosis by PCR IS6110 directly from blood samples of patients with suspected Tuberculosis with Acid-Fast-Bacilli and culture. From 80 patients enrolled, culture results were positive for 25, acid fast bacilli were positive for 15 and blood PCR were positive for 45. Comparing blood PCR result with acid fast bacilli, the sensitivity and specificity were respectively 35% and 87.5% (PPV = 9%, PNV = 21.1%) for PTB. The specificity of blood PCR was 100% (PNV = 72.73%), for EPTB. In comparison with culture blood PCR have a high sensitivity and specificity better than with the acid fast, they were respectively 57.89%, 100% for PTB and 50%, 100% for EPTB. This study is the first established in Tunisia and in Africa aiming to diagnose TB from blood. B-PCR results has shown a high correlation with culture that illustrates the usefulness of B-PCR as a rapid and early diagnostic, combined with others serological results B-PCR can be a solid, rapid and efficient TB diagnostic tools.

Since 1960, Williams and Trotman had dreamed of automating all technical manipulations in bacteriology. However, this switch to automation took several decades to realize. The high cost of instruments and the attachment to classical bacteriology were the main obstacles. Automation began with blood culture incubators, and paved the way for automation in other areas of bacteriology, notably cytology, culture, identification and antibiotic susceptibility testing. Medical laboratories have been quick to recognize the efficiency of these systems and their many advantages. The reduction in turnaround times for bacteriological examinations is one of the changes that have revolutionized laboratory practice. In addition, sensitivity, safety, traceability and quality are more assured with automation. The second revolution is the integration of artificial intelligence into the processing and interpretation of bacteriological analyses. We are currently witnessing the total automation of laboratories and a reduction in human intervention. In this article, we have attempted to address all aspects of bacteriology affected by automation, and the impact of this change on current laboratory practice and quality of healthcare.

Hemoglobin (Hb) measurement is a fundamental biological test, especially in emergency situations where rapid medical decisions are required. Portable hemoglobinometers, such as HemoCue®, provide a delocalized solution for capillary whole blood. The SFBC's POCT News and Issues working group designed and conducted two national surveys to assess the use and management of these devices, both on the clinical and biological side, with 306 and 160 responses respectively. The surveys revealed little effective or desired network connection, heterogeneity in management and training, and only 7% of sites fully accredited, although a quality approach is being structured in 45% of cases. Nearly 80% of biologists suggest reclassification as a rapid diagnostic test, citing difficult standards management and inadequate human resources. However, its daily use goes beyond the simple diagnostic orientation of anemia; blood transfusion decisions without laboratory verification are made by 53% of physicians, while 18% of users are unaware of minimum maintenance procedures, underscoring the need for a rigorous quality approach. The SFBC working group proposes a list of tips to help medical biologists implement this approach, a guarantee of reliable results, in the context of medical decision-making. The selected points are fleet mapping, relations with biomedical and clinical departments, quality documents and minimum method verification, user management, QC management and traceability of results.

A new direction of research was established due to biofilms' infections caused by a mixture of fungal and bacterial species. Diagnosis of these infections becomes more difficult and high doses of drugs are used in treatment, especially in critically ill patients. The aim of the current study was to examine the effects of amphotericin B, in combination with imipenem or colistin against Candida albicans - Acinetobacter baumannii- Proteus mirabilis and Candida tropicalis - Acinetobacter baumannii -Proteus mirabilis polymicrobial biofilms. According to the microdilution method of the Clinical Laboratory Standards Institute (CLSI) published in documents M27-A3 (2008) and M07-A10 (2015) respectively, the susceptibility of the clinical isolates Candida yeasts to amphotericin B and Gram-negative bacteria to imipenem and colistin was determined. A Checkerboard assay was employed to evaluate the efficacy of drugs combinations. The 3- (4,5-dimethylthiazol-2-yl) -2,5-diphenyl tetrazolium bromide (MTT) reduction assay was used to quantify the biofilms. The combination amphotericin B/colistin and amphotericin B/imipenem did not produce obvious effects against the polymicrobial biofilms formed for 48 hours. Whereas colistin alone produced strong effects against Candida albicans-Acinetobacter baumannii and Candida albicans - Acinetobacter baumannii -Proteus mirabilis compared to Candida tropicalis - Acinetobacter baumannii and Candida tropicalis - Acinetobacter baumannii - Proteus mirabilis polymicrobial biofilms. For mixed Candida spp. bacterial biofilms, these results point to the difficulties in eradicating these biofilms, as well as in preventing their development.