[Autoimmunity accreditation: training, accreditation and maintenance of skills in indirect immunofluorescence]. / Accréditation en auto-immunité : formation, habilitation et maintien des compétences en immunofluorescence indirecte.

The ISO 15189 accreditation of biological analysis needs the validation of the analytical methods allowing the evaluation of their performance including all the factors that could influence the quality of their results. The field of autoimmunity includes many analyses and methods such as the indirect immunofluorescence technique (IIF) and the performance of this technique largely depends on the competency of staff members. For each staff member, the required levels of competency have to be precisely defined and evaluated after a period of formation before the final habilitation for the IIF technique. The French group of the international group called EASI (European autoimmunity standardisation initiative) proposes two habilitation forms to be filled with criteria, evidence and maintenance of target skills for the IIF preparation of slides and reading. These forms could be used as a model for the IIF formation and habilitation and have to be adapted to the routine practice of the laboratories.

A common source for a trichinellosis outbreak reported in France and Serbia in 2017.

Trichinellosis is a rare parasitic zoonosis in the European Union. Meat from backyard pigs was the common source for a trichinellosis outbreak caused by Trichinella spiralis, which occurred in France and Serbia in the beginning of 2017. An epidemiological study was conducted in France and Serbia to determine the extent of the outbreak, to identify its source and to implement control measures. Three cases were exposed in Serbia and brought back to France pork delicatessen which they shared with relatives and friends. Around 47 individuals were exposed to the parasitised meat in France and Serbia and 20 cases of trichinellosis were reported (nine in France and 11 in Serbia). Nine of them were female. The diagnosis was delayed, in part because the parasitosis was not known by most physicians, which led to complications in the French cases such as facial paralysis and pulmonary embolism. Health alerts and survey networks are indispensable at a European level to control the disease.

Precision of autoantibody assays in clinical diagnostic laboratories: What is the reality?

BACKGROUND: ISO 15189 accreditation remains a challenge for specialized laboratories. In the field of autoimmunity, beside the crucial problem of absence of standardization, laboratories have to manage the analytical performances of the large panel of assays in terms of sensitivity and specificity, but also on their measurement precision for which no reference values are available on biorepositories. METHODS: As an initiative of the French EASI (European Autoimmunity Standardization Initiative) group, French clinical diagnostic laboratories were requested to participate in a survey aiming to analyze the coefficients of variation (CVs) of intra-run and inter-run variability obtained with assays quantifying 14 different autoantibodies. Two performance goals corresponding to the 90th percentile and the 50th percentile (lowest CV values reached by 90% and 50% of laboratories respectively) defined for three levels of concentration were calculated. The impact on the assay performances of the number of measurements, of the nature of the internal quality control (IQC) and the type of immunoassay, was also analyzed. RESULTS: 414 and 616 values of intra-run and inter-run CVs were collected, respectively. The 50th percentile performance goals were comprised between 1.0% and 8.9% for the intra-run CVs, and between 1.8% and 14.6% for the inter-run CVs. At 90th percentile, the performance goals were comprised between 3.2% and 13.5% for the intra-run CVs, and between 7.3% and 30.8% for the inter-run CVs. CVs calculated from 10 values were similar to those obtained from more values. Higher imprecision was observed when the antibody levels of the IQC was lower than 2 fold the positive threshold. Commercial IQCs gave lower CVs than IQCs derived from patient samples. CONCLUSION: Our results allow proposing some acceptability limits for the precision performances of the autoantibody assays, compatible with the reality of life in diagnostic laboratories and clinical care.

[Research and identification of antinuclear antibodies: analysis of a questionnaire from the European EASI group and confrontation of French practices to international recommendations]. / Recherche et identification des anticorps antinucléaires : analyse du questionnaire européen de l'EASI groupe et confrontation des pratiques françaises aux recommandations internationales.

Antinuclear antibodies (ANA) are prescribed as first-line autoantibodies in suspicion of mainly systemic autoimmune diseases. They include antibodies recognizing antigenic structures localized in the nucleus of cells, but also in the cytoplasm, at the membranes or transitional structures related to the cell cycle. Their research is based on screening and identification tests. For these tests, there is little or no standardization and harmonization of professional practices is necessary. From a questionnaire sent to healthcare professionals involved in the realization and interpretation of tests of autoimmunity, an overwiew of routine practices for the research of the ANA and their identification, was directed by the EASI Group International. Here, we present the results of the survey carried out in France. The analysis of these results faced with that of other countries as well as international recommendations allowed us to propose a synthesis of the main recommendations adapted to the regulatory texts of the NABM in France. These recommendations are addressed to those who prescribe, to those who perform biological analysis and to clinicians and biologists who interpret the results. They allow better understanding and admitting the methodological differences and their evolutions, to encourage the choice of the best technique based on the clinical context, to inform the clinician of the characteristics of the tests used.

Testing anti-neutrophil cytoplasmic antibodies (ANCA): analysis of the European EASI survey on the daily practice of the French laboratories.

Anti-neutrophil cytoplasmic antibodies (ANCA) are mainly searched for the diagnosis of autoimmune vasculitis. They may be found also in other conditions with chronic inflammation. Testing ANCA is based on two main technics: indirect immunofluorescence (IFI) and immunochemical technics to identify the antigenic specificity of the autoantibodies. There is heterogeneity among the laboratories' daily practice. An international group called EASI (European autoimmunity standardisation initiative), composed of 15 countries, comprising France, works to harmonize the practices of the biological diagnosis of the autoimmune diseases. It elaborated a survey consisting of 54 questions related to the analytic parameters of the technics, the algorithms for their use and their biological interpretation; and submitted it to European laboratories. We propose an analysis of the answers obtained from 36 French laboratories specialized in autoimmunity. We compare them to the ones obtained from the other countries and discussed them according to the international recommendations. The analysis reveals a predominant use of IFI as a first step with variable strategies for the identification of the antigenic specificity of the autoantibodies. Overall, the practices are chiefly conformed to the recommendations for the diagnosis of vasculitis, but they are less consensual when the ANCA are performed in other clinical situations.

Celiac disease diagnosis: impact of guidelines on medical prescription in France.

OBJECTIVE: Celiac disease is a complex autoimmune disease affecting patients of any age, who may present a wide variety of clinical manifestations. Different guidelines for the diagnosis and management of celiac disease have been recently published. The aim of this study was to determine whether the recommendations issued in these guidelines have been adopted by physicians in France when celiac disease was suspected. METHODS: A total of 5521 physicians were asked to fill in a detailed questionnaire on diagnosing celiac disease to evaluate their medical practice, as to the type of symptoms leading to the suspicion of celiac disease, the prescription of duodenal biopsy or serological tests, the type of serological tests (anti-tissue transglutaminase, anti-endomysium, anti-gliadin and anti-reticulin antibodies, total immunoglobulin A measurement) prescribed to diagnose celiac disease. RESULTS: The analysis of the responses of 256 general practitioners (GPs), 221 gastroenterologists and 227 pediatricians showed that the protean clinical presentations of celiac disease might be better recognized by gastroenterologists and pediatricians than by GPs. Gastroenterologists asked for duodenal biopsy much more often than GPs and pediatricians when celiac disease was suspected. Serological testing and knowledge of critical markers, prescribed to diagnose celiac disease, differed among GPs, gastroenterologists and pediatricians. CONCLUSION: Analysis of medical prescriptions showed that the recommendations for celiac disease diagnosis are not necessarily followed by physicians, emphasizing the fact that the impact of national or international guidelines on medical behavior should be evaluated.

[The presence of mycobacteria in bronchoalveolar lavage fluid from an immunocompetent patient does not necessarily imply tuberculosis]. / La présence de mycobactéries dans un LBA de sujet immunocompétent n'est pas synonyme de tuberculose.

Mycobacterium tuberculosis is the most frequently identified mycobacterium in the bronchoalveolar lavage fluid (BALF) of immunocompetent patients. Lung infections due to non-tuberculous mycobacteria (NTM) are rare in such patients and then often occur in the context of pre-existing chronic lung disease. We report the case of an immunocompetent 85-year-old woman without pre-existing lung disease in whom M. abscessus was recovered from BALF. Cytological examination of the BALF revealed an increased number of neutrophils and some acid-fast bacilli, all located within neutrophil cytoplasm. This case report contributes a cytological description of BALF in the context of M. abscessus infection, which is poorly detailed in the literature.