Journal of clinical microbiology
-
J. Clin. Microbiol. · Sep 1998
Early detection of Mycobacterium tuberculosis in BACTEC cultures by ligase chain reaction.
The LCx Mycobacterium tuberculosis ligase chain reaction system (Abbott Diagnostic Division, Abbott Park, Ill.) was used to detect M. tuberculosis in 150 consecutive BACTEC vials on the day on which a positive growth index (GI) was recorded. By LCx, M. tuberculosis DNA was detected in BACTEC vials on average 2.6 days before the presence of acid-fast bacilli could be confirmed by microscopic examination. A total of 106 of 108 M. tuberculosis isolates were detected without centrifugation from bottles presenting very low GIs (average, 70; median, 33). No false-positive result was obtained from nontuberculous mycobacteria or from isolates with contaminants.
-
J. Clin. Microbiol. · Aug 1998
Clinical evaluation of the Gen-Probe Amplified Direct Test for detection of Mycobacterium tuberculosis complex organisms in cerebrospinal fluid.
Eighty-four cerebrospinal fluid (CSF) samples from different children who presented with signs and symptoms of meningitis were evaluated for the presence of Mycobacterium tuberculosis complex organisms by the Gen-Probe Amplified Mycobacterium tuberculosis Direct Test (MTD; Gen-Probe, San Diego, Calif.). All CSF samples had negative acid-fast smears by the Ziehl-Neelsen staining method. M. tuberculosis was recovered from five samples. ⋯ The Gen-Probe MTD was 33% sensitive and 100% specific for detecting M. tuberculosis complex organisms in these 84 CSF samples. If the cutoff values for positive results were decreased for the MTD (> or = 11,000 versus > or = 30,000 relative light units), the sensitivity increased to 83% and the specificity remained 100%. These results for the MTD are encouraging considering that TBM is a highly fatal disease and difficult to diagnose by conventional laboratory techniques.
-
J. Clin. Microbiol. · Jul 1998
Evidence of Toscana virus variants circulating in Tuscany, Italy, during the summers of 1995 to 1997.
The Toscana virus can cause neurological infection in adults. This study of 112 cases of acute meningitis which occurred during the summers of 1995, 1996, and 1997 demonstrated the presence of viral RNA in the cerebrospinal fluid of 56 patients. Their sequence analysis shows four variants of the Toscana virus.
-
J. Clin. Microbiol. · Jun 1998
Randomized Controlled Trial Clinical TrialPositive result by serology indicates active Helicobacter pylori infection in patients with atrophic gastritis.
Patients with atrophic corpus gastritis and elevated Helicobacter pylori antibody titers but 13C-urea breath test (13C-UBT) and histology results negative for H. pylori were randomized into eradication therapy or follow-up only. Antibody levels decreased significantly in six out of seven patients in the eradication group, while in the follow-up group, the titers declined in only one out of eight patients. In patients with atrophic corpus gastritis, positive serology results may indicate an ongoing infection in spite of negative 13C-UBT and histology results.
-
J. Clin. Microbiol. · May 1998
Use of Roche AMPLICOR Mycobacterium tuberculosis PCR in early diagnosis of tuberculous meningitis.
Several nucleic acid-based amplification tests are available for the detection of Mycobacterium tuberculosis, but few data are available on their use in the diagnosis of tuberculous meningitis (TBM). We performed a prospective study to assess the Roche AMPLICOR Mycobacterium tuberculosis PCR test (TB AMPLICOR) for use in the diagnosis of TBM and compared it with direct Ziehl-Neelsen staining of smears, radiometric culture for M. tuberculosis, and clinical and cerebrospinal fluid (CSF) findings. Eighty-three CSF specimens collected from 69 patients with suspected meningitis in South Africa were tested by TB AMPLICOR. ⋯ The sensitivity of TB AMPLICOR for detecting cases of definite and probable TBM in patients from whom CSF specimens had been collected less than 10 days into antituberculosis treatment was 60.0%. Specimens from all 29 patients not treated for TBM were negative by the TB AMPLICOR, giving a 100% specificity. TB AMPLICOR is therefore more sensitive than the combination of Ziehl-Neelsen staining of smears and radiometric culture for M. tuberculosis and is a rapid and highly specific diagnostic test for TBM.