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Summary Introduction Quantitation of ADAMTS13 activity, functional inhibitors, and autoantibodies is crucial in diagnosis and management of thrombotic thrombocytopenic purpura. We compared and optimized commercial assay kits and validated a testing panel. Methods Citrated plasma specimens from healthy volunteers and residual samples submitted for clinical testing were used in the study. Commercially available ADAMTS13 activity assays including ACTIFLUOR™ ADAMTS13 (Sekisui Diagnostics, Stamford, CT, USA), LIFECODES ATS-13 (Gen-Probe Inc., San Diego, CA, USA), and TECHNOZYM® ADAMTS-13 (Technoclone, Vienna, Austria) were evaluated. Functional inhibitor assays were performed using internally developed mixing protocols. Two autoantibody assays were also evaluated: IMUBIND® (Sekisui Diagnostics) and TECHNOZYM® ADAMTS-13 INH ELISA kits (Technoclone). Results A laboratory-developed assay using ACTIFLUOR™ reagents showed best agreement with the reference method, and full validation showed a reportable range of 5% (LLOQ) to 114% with a reference interval of ≥68%. Both intra- and interassay coefficients of variation were

Anti-LGI1 encephalitis is a subgroup of autoimmune encephalitis, characterized by memory impairments, seizures, and behavioral problems. The diagnosis can be made by clinical manifestation with a help of serum autoantibody test. There was lack of imaging studies to evaluate and monitor the disease activity by anatomical and functional information. Here, we report serial F-FDG PET/CT findings in a patient with anti-LGI1 encephalitis. Intense F-FDG uptake was initially noted in bilateral limbic system at active disease status, and then decreased and eventually normalized according to the clinical improvement after treatment. F-FDG PET/CT can be used to evaluate treatment response of encephalitis.

Immunology laboratories perform diagnostic tests to identify the autoantibody markers needed to classify disorders which are complex, often rare, and hard to define. The recent introduction of new markers and the use of increasingly complicated assay procedures can cause difficulty in interpreting test results. Moreover, during the performance of some tests, some autoantibodies which were not requested, and consequently not expected, may be identified by chance. It is advisable for these positive results to be reported only when they have a high predictive value and suggest the possible presence of an autoimmune disease. An interpretative comment on autoantibody test results is crucial in a number of cases: when autoantibodies with a significant clinical correlation (high specificity) are found; when two or more methods are used to determine the same autoantibody and the results disagree; when unexpected autoantibody positivity is found and in case of results generated by further diagnostic tests conducted by the laboratory on its own initiative. The interpretative comment should be based on the patient's personal characteristics (sex, age) and the other laboratory parameters available; it should specify the diagnostic accuracy of the assay methods used, the clinical and diagnostic correlations of the antibodies which tested positive, and any further tests needed to complete the diagnostic process.

During the 12th International Workshop on Autoantibodies and Autoimmunity (IWAA) held in Sao Paulo, Brazil, on August 28, 2014, a full day session was devoted to establishing a consensus on the nomenclature of staining patterns observed in the antinuclear antibody (ANA) indirect immunofluorescence test on HEp-2 cells. The current report summarizes the collective agreements with input from the host Brazilian and international communities that represented research, clinical, and diagnostic service laboratories. Patterns are categorized in three major groups (nuclear, cytoplasmic, and mitotic patterns) and each pattern has been defined and described in detail. The consensus nomenclature and representative patterns are made available online at the International Consensus on Antinuclear antibody Pattern (ICAP) website (www.ANApatterns.org). To facilitate continuous improvement and input, specific comments on ICAP are encouraged and these will be discussed in subsequent ICAP meetings. The ultimate goal with the establishment of the ICAP is to promote harmonization and understanding of autoantibody test nomenclature, as well as interpretation guidelines for ANA testing, thereby optimizing usage in patient care.

During the last 25 years clinical autoantibody determinations have changed dramatically. Old and slow techniques with high diagnostic specificity have been replaced with automated and faster techniques that most often have a higher diagnostic sensitivity at the expense of a lower diagnostic specificity. Newer techniques are mostly quantitative, allowing for follow-up of autoantibody levels. Whereas the older procedures utilized autoantigens in soluble and native states, most modern techniques rely on autoantigens attached to surfaces, with the risk of exposure of denatured epitopes. Comparisons between antibody measurement techniques can be obtained from the results of external quality assessment programs. Yet as the main objective for external quality assessment is the monitoring of clinical laboratories they cannot focus on the kind of low-level and often polyreactive sera which are common in the real world and in which a single definite target response cannot be easily defined. Such common sera are very useful, however, for analysis of differences between autoantibody measurement techniques. The European Consensus Finding Study Group on Autoantibodies has been working with this approach for 28 years.

The purpose of this work is to assess the validity of an ultrasonographic sign, micronodulation, in the diagnosis of Hashimoto thyroiditis. Among 101 patients found to have ultrasonographic features of micronodulation, 57 patients had autoantibody test results available. Fifty-four patients were positive and three were negative for the autoantibodies. Therefore, the positive predictive value for micronodulation in diagnosing Hashimoto thyroitis is 94.7%. The micronodules were 0.1 to 0.65 cm in size, hypoechoic, and surrounded by an echogenic rim. This corresponds to accentuated lobulation on the pathologic specimen. Although micronodulation is highly diagnostic of Hashimoto thyroiditis, the ultrasonographic features of eight biopsy-proved masses caused by Hashimoto thyroiditis varied and were not specific for the disease.

Four weeks ago (31 July, p 273) we presented the case of Mrs Prior, a 40 year old woman with cystitis, itching, and rash. When her biochemical results showed raised liver enzyme concentrations, her general practitioner was advised to refer her for ultrasonography and an autoantibody test (7 August, p 342). The scan suggested the possibility of hepatic infiltration but the autoantibody screen gave negative …

7030 Background: An AABT to aid in lung cancer diagnosis has been recently developed. While less sensitive than computed tomography (CT), it can detect smaller and less-advanced cancers and has gre...