American journal of clinical pathology
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The study examined a "percent correction" formula for evaluating mixing study results comparing a 1:1 mix with a new 4:1 mix of patient plasma with citrated normal plasma for a prolonged activated partial thromboplastin time (aPTT) and/or prothrombin time (PT). The study also examined 3 suggested definitions of correction for evaluating mixing study results for comparison. Applicability of percent correction for evaluating the aPTT 4:1 mix testing with and without incubation also was studied. ⋯ The percent correction of the aPTT 4:1 mix testing after incubation had better sensitivity and specificity that that of testing immediately. Nevertheless, these procedures were complementary to each other. The percent correction using the aPTT or PT 4:1 mix seemed to offer a simple, objective, and effective criterion for evaluating mixing study results.
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Am. J. Clin. Pathol. · Jan 2002
A systematic study of Epstein-Barr virus serologic assays following acute infection.
We determined the presence of IgG and IgM antibody to viral capsid antigen (VCA-IgG, VCA-IgM) and IgG antibody to the Epstein-Barr virus nuclear antigen (EBNA) by indirect immunofluorescence assay (IFA) and enzyme-linked immunosorbent assay (ELISA) during the acute illness and at 1, 2, 6, and 48 months in a prospective population-based case series of 95 persons with an acute illness serologically confirmed as Epstein-Barr virus infection. The acute illness was characterized by the presence of VCA-IgG and VCA-IgM (by ELISA) and by the absence of EBNA in most, but not all, patients. ⋯ The primary differences between the 2 serologic test methods were the increased persistence of VCA-IgM during follow-up by ELISA and the earlier detection of EBNA by IFA. Clinicians should consider the illness stage and the laboratory technique to appropriately interpret serologic test results in suspected cases of mononucleosis caused by the Epstein-Barr virus.
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Meta-analysis is the structured and systematic integration of information from different studies of a given problem. It has been widely used to integrate findings of randomized controlled trials (RCTs) investigating the efficacy of therapeutic interventions, but its use in pathology has lagged behind its use in clinical medicine. ⋯ Three differences between RCTs and studies of diagnostic test accuracy are identified, and 4 possible obstacles to the use of meta-analysis in pathology are discussed. Despite these specific difficulties in the meta-analysis of diagnostic test data, meta-analysis can (and should) be used to produce valid summary estimates of the diagnostic accuracy of laboratory tests across all available studies.
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Am. J. Clin. Pathol. · Dec 2001
Case ReportsPrimary diagnosis of whipple disease manifesting as lymphadenopathy: use of polymerase chain reaction for detection of Tropheryma whippelii.
Whipple disease is a rare, chronic multisystem disease associated with the recently characterized organism Tropheryma whippelii. Extraintestinal manifestation involving the central nervous system, heart, and joints occasionally occurs. Involvement of the abdominal lymph nodes, especially the mesenteric and periaortic nodes, is not uncommon. ⋯ Electron microscopic evaluation confirmed the presence of rod-like organisms. DNA from each sample was amplified by the polymerase chain reaction using a specific set of oligonucleotide primers developed against the 16S ribosomal RNA coding sequence of T. whippelii. The histopathologic features and differential diagnosis of lipogranulomatous lymphadenopathy secondary to Whipple disease, as well as use of molecular-based assays, are discussed.
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Am. J. Clin. Pathol. · Feb 2001
Multicenter Study Comparative Study Clinical TrialPoint-of-care prothrombin time measurement for professional and patient self-testing use. A multicenter clinical experience. Oral Anticoagulation Monitoring Study Group.
We enrolled 386 subjects in a multicenter study of a point-of-care (POC) prothrombin time (PT) testing device. POC tests were performed by health care professionals using venous and finger-stick specimens and by patients using finger-stick specimens. Venous blood also was analyzed in the local hospital laboratory and a national reference laboratory. ⋯ Patients overwhelmingly reported satisfaction with the self-test, including the finger stick and device operation. The INR from the POC device is clinically equivalent to the laboratory INR for assessment of anticoagulation status and management decisions in professional and self-testing environments. Patients can learn to perform accurate PT testing, and POC PT testing is feasible in patients' homes.