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Background: Insulin measurement is used for the diagnosis of hypoglycemia and for insulin pharmacokinetic evaluations. We assessed the analytical and clinical performance of the ARCHITECT® insulin assay, a chemiluminescent immunoassay recently introduced for the ARCHITECT i2000 fully automated immunoassay analyzer (Abbott Laboratories). We also tested whether major insulin analogs cross-reacted with the immunoassay reagents. Methods: We used Clinical and Laboratory Standards Institute protocols to assess the analytical performance of the ARCHITECT insulin assay and compared its accuracy with that of the E-test TOSOH II (IRI) from TOSOH Corporation. We used 3 recombinant insulin analogs (lispro, aspart, and glargine) to evaluate the cross-reactivity of insulin analogs with the ARCHITECT immunoassay reagent. Results: The total CV for the ARCHITECT assay was Conclusions: The ARCHITECT insulin assay showed favorable basic performance, including reproducibility, dilution linearity, detection limit, and effects of interfering substances. When interpreting results, clinicians and laboratory pathologists should be aware of the cross-reactivity of the ARCHITECT and other immunoassays to specific insulin analogs prescribed to diabetes patients.

Background: A new enzyme immunoassay (EIA) for automated detection of antinuclear antibodies (ANAs) uses a mixture of HEp-2 cell extracts and multiple recombinant nuclear antigens immobilized on beads. We compared this EIA and an immunofluorescence (IF) assay in a large group of patients and controls. Methods: We studied 492 healthy individuals and 307 patients with connective tissue diseases (CTDs). Sera were tested by an automated EIA (COBAS® Core HEp2 ANA EIA; Roche Diagnostics) and IF. Samples were also tested for eight disease-specific antibodies, including antibodies against U1RNP, Sm, SSA/Ro, SSB/La, Scl-70, Jo-1, dsDNA, and centromere. Results: Areas under ROC curves for the EIA were greater than (P = 0.008–0.012) or numerically identical to areas for the IF method for each of six CTDs studied. ROC areas for EIA were 0.98 (95% confidence interval, 0.95–0.99), 0.99 (0.96–1.00), and 0.99 (0.98–1.00) in systemic lupus erythematosus (n = 111), systemic sclerosis (n = 39), and mixed connective tissue disease (n = 33), respectively. For all 258 CTD patients with conditions other than rheumatoid arthritis (RA), the sensitivity and specificity of the IF method at a cutoff dilution of 1:40 were 92% and 65%, respectively, vs 93% and 79% for the EIA at a cutoff of 0.6. For the IF method at a cutoff dilution of 1:160, sensitivity and specificity were 81% and 87%, respectively, vs 84% and 94%, respectively, for the EIA at a cutoff of 0.9. For 207 sera containing at least one of eight disease-specific ANAs, positivities for the EIA and the IF method were 97.1% and 97.6%, respectively, at cutoffs of 0.6 and 1:40 (P = 0.76). Conclusions: An EIA that can be performed by a fully automated instrument distinguishes CTDs (except RA) from healthy individuals with both higher sensitivity and specificity than the IF method when the cutoff index was set at 0.9. Moreover, it can be used to exclude the presence of disease-specific ANAs by setting the cutoff index at 0.6 with almost the same efficacy as the IF method.

レイノー現象の発症には末梢血中のセロトニンによる一過性の微小血栓形成が血小板-血管壁系の異常を引き起こしている可能性が注目されている.我々は微小な血小板凝集を検出可能なレーザー散乱粒子計測型血小板凝集能測定装置を用いて,レイノー現象を有する患者の血小板凝集能を検討した.まず自然凝集およびセロトニン凝集について検討を行った.次にこれらの患者についてセロトニン受容体(5-HT 2 A)拮抗剤(塩酸サルポグレラート: SPG)投与前後での血小板凝集能の変化を観察した.レイノー現象を有する患者10名と健常成人10名を対象とした. SPG投与前の患者群と健常者群の両者で自然凝集は認めず,セロトニン凝集は健常者群に比しSPG投与前の患者群で有意に低下していた.患者群のSPG投与8週間後のセロトニン凝集は投与前に比し亢進し, SPGを服用していない健常者群とほぼ同程度の凝集がみられるようになった. SPGの長期投与によって血漿セロトニン濃度が低下することが知られており,その結果血小板表面のセロトニン受容体発現の亢進を介して外来性セロトニンに対する凝集が亢進した可能性が考えられた.

ライト付きスタイレット(TRACHLIGHTTM:以下TL)は,非直視下に頸部からの透過光を目安に気管内挿管する方法で,操作法も比較的容易に習得でき,挿管困難症例に対してもその有用性が報告されている.今回われわれは過去3回の麻酔の際,喉頭鏡および気管支ファイバーで気管内挿管できなかった患者に対し,TLを使用することにより容易かつ短時間で挿管に成功した症例を経験した.TLは挿管困難症例に対して有効な手段の一つと考えられた.