84) Immunohistochemical laboratory proficiency - the role of external quality assessment Forfattere: Mogens Vyberg and Søren Nielsen, NordiQC, Institute of Pathology, Aalborg Hospital, Aarhus University Hospital, Denmark Abstract: Immunohistochemical (IHC) assays are highly complex analyses used in diagnostic pathology to aid in identification and characterization of tumour types. Standardization of IHC staining reactions is vital for reliable and comparable results. Yet, staining quality varies greatly between laboratories. Nordic Immunohistochemical Quality Control (NordiQC) was established at Aalborg Hospital in 2003 as an independent scheme for external quality assurance (EQA), with current participation of about 320 laboratories from 40 countries. Annually about 16 challenges are performed in a general module and 6 tests in a breast cancer module. The general results of each run are presented on the website www. nordiqc.org. During 8 years, NordiQC has tested staining for about 80 of the clinically most relevant epitopes up to 10 times based on more than 25,000 multi-tissue sections. The over-all scores have been almost evenly distributed between optimal (36%), good (33%) and insufficient (i.e., borderline or poor, 31%). The causes of insufficient stains could be identified in the large majority of cases, mostly ascribed to less successful primary Abs, improper calibration of the Ab concentration, and insufficient epitope retrieval. Less successful primary Abs were identified as the major cause of suboptimal stains in 18% of the cases, while improper calibration of primary Ab concentration was the major cause in 39%. Following tailored NordiQC recom¬mendations, complying laboratories improved in more than 70%, while non-responding laboratories improved in about 15%. Indsendt af: Overlæge Mogens Vyberg, (Patologisk Institut, Aalborg Sygehus) Uddannelse: Speciallæge i patologisk anatomi E-mail: mv@rn.dk / Telefon: 9932 1604 Forskningsansvarlig på afdelingen: Mogens Vyberg
85) Altered Brain Microstructure assessed by Diffusion Tensor Imaging in Patients with Diabetes Mellitus and Gastrointestinal Symptoms Forfattere: Jens Brøndum Frøkjær, Lars Wiuff Andersen, Christina Brock, Magnus Simrén, Maria Ljungberg, Eirik Søfteland, Georg Dimcevski, Hans Gregersen & Asbjørn Mohr Drewes. Abstract: Objective: In patients with longstanding diabetes mellitus (DM) there is increasing evidence of abnormal sensory processing in the central nervous system, also including gastrointestinal (GI) sensation. Using magnetic resonance diffusion tensor imaging, we characterized brain microstructure in areas involved in visceral sensory processing and correlated these findings to clinical parameters. Methods: Twenty-six patients with DM and GI symptoms and 23 controls were studied in a 3T MR scanner. Apparent diffusion coefficient (ADC) (i.e. diffusivity of water) and fractional anisotropy (FA) (i.e. organisation of fibres) values were assessed in the cingulate cortex, insula, prefrontal and secondary sensory cortex, amygdala, corona radiata and corpus callosum. Results: Patients had decreased FA values, i.e. reduced organisation, compared to controls in 1) anterior, mid and posterior cingulate cortex, 2) prefrontal cortex grey matter, 3) corona radiata, 4) secondary sensory cortex, 5) anterior insula white and grey matter, and 6) posterior insula grey matter (all P<0.05). The microstructural changes were for some areas correlated to the clinical parameters such as bloating (in anterior insula), mental wellbeing (in prefrontal cortex, corona radiata, amygdala, cingulate cortex and anterior insula), physical wellbeing (in posterior insula), and the presence of gastroparesis (in anterior insula). Conclusion: Our findings suggest that microstructural changes of brain areas involved in visceral sensory processing might be involved in the pathogenesis of gastrointestinal symptoms in diabetes patients. Indsendt af: Jens Brøndum Frøkjær, (Radiologisk Afdeling, Aalborg Sygehus) Uddannelse: E-mail: jebf@rn.dk / Telefon: Forskningsansvarlig på afdelingen: Jens Brøndum Frøkjær
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