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Articles & Papers
To investigate whether the use of recombinant early antigens for detection of antibodies to human cytomegalovirus (HCMV) gene products CM2 (UL44, UL57) and p52 (UL44) is specific in the diagnosis and differentiation of active HCMV infection in a subset of patients with chronic fatigue syndrome (CFS), a diagnosis which is often missed by the current ELISA assay thatuses crude viral lysate antigen....learn more
Tuberculosis in immunocompromised patients is often caused by Mycobacterial species other than Mycobacterium tuberculosis. Thus, detection of and differentiation between M. tuberculosis and nontuberculosis species is necessary for diagnosis of disease in these patients. Furthermore, when tissue changes show granulomatous inflammation, quick confirmation testing for mycobacterial infection is needed for conclusive diagnosis. The aim of this study was to validate the utility of a real-time polymerase chain reaction (PCR) assay in conjunction with the MagNA Pure LC automated extraction system for the detection of mycobacterial DNA from ormalin-fixed, paraffinembedded specimens. A total of 46 archived, paraffin-embedded, fixed specimens showing granulomatous inflammation were studied for mycobacterial infection by real-time PCR. Bacterial DNA was extracted and isolated using the MagNA Pure extraction system. Real-time PCR was performed on the Light-Cycler using the Artus Real Art Mycob Diff ASR kit from Qiagen. Thirteen of the 46 patient specimens were positive for mycobacterial infection by acid-fast bacilli (AFB) stain. Of the 13 reported positive by AFB stain, 12 where positive by real-time PCR. All 13 specimens reported positive by AFB were sent for culture confirmation. Eleven of 13 were returned positive by culture. Specimens reported as negative by culture and positive by real-time PCR were confirmed positive by a second PCR method from another reference laboratory. We believe that these studies are beneficial in the differential diagnosis of mycobacterial infection from fixed tissue specimens where tuberculosis might not have been clinically initially suspected and when specimens are not suitable for microbiologic examination.....learn more
The Digene Hybrid Capture 2 (hc2) high-risk human papillomavirus (HPV) DNA test (Digene, Gaithersburg, MD) is widely used for triage of women with atypical squamous cells of undetermined significance. Results in a “retest zone” (weakly positive tests) are repeated up to 2 times according to the Digene-recommended algorithm. We studied 56 cervical samples in the retest zone. Specimens were tested by a multiplex polymerase chain reaction (PCR)-based genotyping assay, and relevant cytopathologic results were reviewed. Digene results were compared with a reference standard that combined PCR genotyping and cytopathology results.The first repeated Digene assay yielded a sensitivity of 85.2% and a specificity of 62.1% with false-positive and false-negative rates of 40.0% and 15.4%, respectively. The 22 negative samples underwent a second retest and 18 (82%) were negative by the reference standard. The combined first and second retest sensitivity, specificity, and predictive values remained unchanged from the first retest alone. Repeating specimens in the retest zone is necessary,
but a second retest does not offer advantages over the first retest....learn more
Human cytomegalovirus (HCMV) IgM serum antibodies to two nonstructural gene products UL44 and UL57 (p52 and CM2) were assayed in patients with the diagnosis of the chronic fatigue syndrome (CFS) according to criteria established by the US Centers for Disease Control and Prevention. A subset of 16 CFS patients demonstrated HCMV IgG, but no HCMV IgM serum antibodies to conformational structural HCMV antigens (designated, V). By convention, these findings are interpreted to indicate only a remote HCMV infection. However, HCMV IgM 2 p52 and CM2 antibodies were uniquely present in these 16 CFS patients. Other CFS patients
with similar HCMV (V) IgG antibodies (18 patients), non-fatigued HCMV (V) IgG-positive control patients (18 patients), random HCMV (V) IgG-positive control patients from a clinical laboratory (26 patients), and non-fatigued HCMV (V) IgG-negative control patients (15 patients) did not have HCMV, IgM p52 or CM2 serum antibodies (p < 0.05) . Control HCMV (V) IgG-positive patients had no serum IgM HCMV (V) antibodies to conventional structural HCMV (V) antigen. Thus, 77 various control patients did not contain IgM p52 or CM2 serum antibodies. The presence of IgM p52 and/or CM2 HCMV serum antibodies in this subset of CSF-specific patients may detect incomplete HCMV ultiplication in which a part of the HCMV protein-coding content of the HCMV genome is processed, but remains unassembled. These findings suggest that the presence of HCMV IgM p52 and CM2 serum antibodies may be a specific diagnostic test for the diagnosis of a subset of CFS patients. Further, these data suggest an etiologic relationship for HCMV infection in this group of CFS patients....learn more
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