Tubercle最新文献

A case of extensive intracranial tuberculoma is presented. The patient had been treated for 5 years with a standard antituberculosis regimen but she had been grossly non-compliant. This had led to emergence of multi-resistant Mycobacterium tuberculosis producing progressive disease and extensive cranial nerve damage and proptosis. The unusual CT and angiographic appearances cast doubt on the original diagnosis and a brain biopsy was necessary. Mycobacterium tuberculosis resistant to isoniazid, rifampicin, ethambutol, ethionamide, pyrazinamide, clofazimine and PAS was cultured from the brain biopsy specimen and from an associated groin abscess. A novel regimen of isoniazid, cycloserine, amikacin and ciprofloxacin produced clinical improvement of symptoms and radiological resolution.

32 isolates belonging to the Mycobacterium tuberculosis complex were examined by pyrolysis mass spectrometry (PyMS). This technique demonstrated that recent clinical isolates of M. africanum were indistinguishable from those of M. bovis and together formed a homogeneous group distinct from M. tuberculosis. Isolates of BCG were heterogeneous and more closely related to laboratory-adapted strains of M. tuberculosis than to recent isolates of either M. tuberculosis or M. bovis.

PyMS is a simple and inexpensive technique which gives interesting information on the relationships between members of the M. tuberculosis complex and can make the clinically important distinction between strains of M. bovis and M. tuberculosis accurately and much more rapidly than conventional techniques.

The value of ascites gamma interferon concentration and ascites adenosine deaminase activity in distinguishing tuberculosis from other causes of ascites was examined in a prospective study of 86 patients with ascites, including 16 with tuberculous peritonitis. Gamma interferon concentration was higher in tuberculous peritonitis than in the other causes of ascites (p < 0.0001), and a cut-off between 3 and 9 u/ml reached a sensitivity and a specificity of 100%. The mean (± SD) gamma interferon level in tuberculous ascites was 39.3 ± 18.3 u/ml in patients seronegative for HIV and 14.2 ± 4.7 μ/ml in patients with AIDS (p = 0.01). Adenosine deaminase activity in tuberculous ascites was also higher than in the other causes of ascites (p < 0.0001), and a cut-off of 40 u/l reached a sensitivity of 100% and a specificity of 97%. The two false positives for adenosine deaminase test were true negatives for the gamma interferon test. There was no significant correlation between gamma interferon concentration and adenosine deaminase activity either in tuberculous ascitis or in any other group. This study suggests that ascites gamma interferon determination may be very useful in the screening of tuberculous peritonitis, but Its cost makes it advisable to use adenosine deaminase activity as a routine test, at least in areas where tuberculosis is endemic.

Sputum and faeces were obtained from 276 patients on admission to a study of drug resistance in Hong Kong. Acid-fast bacilli were detected microscopically in 103 (37%) sputum specimens and 135 (49%) yielded Mycobacterium tuberculosis on culture. Three methods were used to decontaminate faeces prior to dilution and culture in selective liquid Kirchner medium. A total of 61 faecal specimens were positive for M. tuberculosis on culture and, of these, pretreatment with sodium hydroxide yielded 60 (98%), Portaels modification of Wolinsky and Rynearsons's method 28 (46%) and the combined use of benzalkonium chloride and 1-hexdecylpyridinium chloride yielded 32 (52%). It is recommended that faeces should be treated with sodium hydroxide followed by dilution and culture in selective media, although it may be necessary to formulate new selective media for mycobacterial species other than M. tuberculosis.

The purpose of this study was to develop and evaluate a guinea pig model of experimental airborne tuberculosis for its ability to assess chemotherapeutic regimens for their efficacy against virulent tubercle bacilli in vivo during the initial phase of treatment. The tissues examined included primary lung lesions and the metastatic foci in lung and spleen which result from the naturally occurring bacillaemia. The treatments examined, INH+RIF, INH+EMB, EMB+RIF, were initiated 4 weeks after infection and were continued for 8 weeks. Although minor differences were observed in the time of onset of a significant bactericidal effect or in the rate of decline in the microbial population, all three treatment combinations resulted in a significant reduction in the number of M. tuberculosis H37Rv recovered from primary lung lesions, primary lesion-free lung lobes and spleen. X-rays taken of excised inflated lung lobes showed a relationship between the degree of calcification of primary lung lesions and the number of surviving bacilli.

The in vitro and in vivo activities of sparfloxacin (AT-4140) against M. tubercubsis are reported. The MICs of sparfloxacin for 50% and 90% of 18 clinical isolates were, respectively, 0.25 and 0.5 mg/l, one or two dilutions lower than that of ciprofklxacin and ofloxacin. In mice infected intravenously with 0.1 mg M. tuberculosis H37Rv strain, the minimal effective dosage of sparfloxacin, as assessed by survival rate, spleen enlargement and gross lung lesidns, was 12.5 mg/kg. The activities of various regimens were in the following rank order: INH 25 mg/kg = sparfloxacin 50–100 mg/kg > ofloxacin 300 mg/kg > (or =) sparfloxacin 25 mg/kg > spartloxacin 12.5 mg/kg > (or =) ofloxacin 200 mg/kg > ofloxacin 100 mg/kg > (or =) negative control. Therefore, on a weight to weight basis, sparfloxacin was six to eight-fold more active against M. tuberculosis infection in mice than ofloxacin. In addition, WIN 57273, a new broad-spectrum fluoroquinolone, at a dosage of 100 mg/kg daily, was inactive against M. tuberculosis infection.