Rapid Diagnosis Of Tuberculous Meningitis Research Articles

Rapid diagnosis of tuberculous meningitis by polymerase chain reaction

The polymerase chain reaction (PCR) in cerebrospinal fluid was compared with conventional bacteriology and an enzyme—linked immunosorbent assay (ELISA) for cerebrospinal fluid antibodies in the diagnosis of tuberculous meningitis (TBM). PCR was the most sensitive technique; it detected 15 (75%) of 20 cases of highly probable TBM (based on clinical features), 4 (57%) of 7 probable cases, and 3 (43%) of 7 possible cases. ELISA detected 11 (55%) of the highly probable cases and 2 each of the probable and possible cases. Culture was positive in only 4 of the highly probable cases. Among the controls (14 pyogenic meningitis, 3 aseptic meningitis, 34 other neurological disorders), 6 subjects tested early in the study (2 pyogenic meningitis, 4 other disorders) were PCR positive. Second DNA preparations from their stored cerebrospinal fluid samples were all PCR negative, suggesting that the false-positive results were due to cross-contamination. 18 PCR-positive TBM samples retested were all still PCR positive. The antibody ELISA was positive in 3 controls despite the use of a high cutoff value.

Rapid diagnosis Of tuberculous meningitis by polymerase chain reaction (PCR)

Using a rapid and highly sensitive method for the diagnosis of tuberculous meningitis by polymerase chain reaction (PCR), we detected the Mycobacterium tuberculosis genome in CSF of 5 of 6 patients with clinically diagnosed tuberculous meningitis. The genome was not present in CSF from 10 patients with other types of meningitis and 10 normal controls.

Rapid diagnosis of tuberculous meningitis by frequency-pulsed electron-capture gas-liquid chromatography detection of carboxylic acids in cerebrospinal fluid

The frequency-pulsed electron-capture gas-liquid chromatography technique described previously by Brooks et al. was modified and applied to the studies of coded and routine clinical specimens. Uncentrifuged cerebrospinal fluid (2 ml) was extracted under acidic conditions, derivatized, and analyzed by frequency-pulsed electron-capture gas-liquid chromatography on large-bore fused silica polar and nonpolar capillary columns. The frequency-pulsed electron-capture gas-liquid chromatography profile of carboxylic acids (C2 through C22) along with identification of tuberculostearic acid, established by retention time comparison of derivatized tuberculostearic acid and derivatized sample extract, strongly suggests the presence of Mycobacterium tuberculosis in patients with lymphocytic meningitis. Results from 41 coded cases and 75 clinical cases showed that the frequency-pulsed electron-capture gas-liquid chromatography test had a specificity of 91% and a sensitivity of 95%.

Rapid Diagnosis of Tuberculous Meningitis by ELISA to Detect Mycobacterial Antigen and Antibody in the Cerebrospinal Fluid

Rapid Diagnosis of Tuberculous Meningitis by ELISA to Detect Mycobacterial Antigen and Antibody in the Cerebrospinal Fluid

New approaches to the rapid diagnosis of tuberculous meningitis.

The diagnosis of tuberculous meningitis depends on identifying Mycobacterium tuberculosis in the CSF by direct staining or culture. Because of the catastrophic nature of this illness and because effective specific therapy is available, clinicians generally cannot delay treatment to receive a definitive laboratory diagnosis, and therapy is often begun on a presumptive basis. At the same time, other forms of meningitis may mimic tuberculosis, and some of these other forms demand different kinds of specific therapy. Thus, there remains a major need for additional methods of rapidly diagnosing tuberculous meningitis. The reports that appear elsewhere in this issue of the Journal (by Ribera and his colleagues [1], of the measurement of adenosine deaminase activity in CSF, and by Kadival and his co-workers [2], of the detection of mycobacterial antigen in CSF) are important contributions that may lead to new methods for rapidly diagnosing tuberculous meningitis. If mycobacteria were easily identifiable by direct smear of CSF from most patients, the diagnostic problem would not exist. In their recent review of tuberculous meningitis, Molavi and LeFrock [3] stated that mycobacteria were identified by smear of CSF in KWo^O^o of cases in most series and by culture in 45(7o-90(7o of cases. A careful modern study of the bacteriologic diagnosis of tuberculous meningitis is that of Kennedy and Fallon [4]. They found that the initial CSF specimen was positive in 37^0 of patients on direct smear and in 52^0 on culture. Examining second and third CSF specimens added substantial numbers of positives, but examining additional specimens yielded few additional diagnoses. Ultimately, 87^0 of patients had a positive CSF smear and 83 ^o, a positive culture. The diagnostic yield of CSF smear and culture in other studies has generally been lower. Any proposed test for the rapid diagnosis of tuberculous meningitis must be examined, with respect