David J. Dawson

Unusual mycobacteria in 5 Cases of opportunistic infections

Five cases of infection due to an unusual mycobacterium are recorded, and the growth requirements and histological findings are discussed. On initial culture, these mycobacteria could be grown only on Lowenstein-Jensen medium containing ferric ammonium citrate, and the histology of the skin lesions was not always typical of mycobacterial disease.

Atypical mycobacteria isolated from clinical material in south-eastern Queensland.

Summary Mycobacteria were isolated from specimens from 726 of 6,436 persons investigated in 1 year in a tuberculosis laboratory in Brisbane, Queensland. Isolates from 634 persons were atypical mycobacteria and, of those identified, more than half belonged to the Mycobacterium avium‐intracellular‐scrofulaceum complex. Sero‐agglutination studies showed that the majority of these were M. intracellulare. Mycobacterium scrofulaceum and M. kansasii were uncommon, and M. avium and M. xenopi were not isolated.

Tuberculosis in australia: An analysis of cases identified in reference laboratories in 1986-88

&NA; The Special Interest Group in Mycobacteria within the Australian Society for Microbiology has carried out a collaborative study of cases of tuberculosis diagnosed in Australian reference laboratories in the years 1986, 1987 and 1988. Annual totals of 574, 584 and 613 respectively, suggest that the incidence of bacteriologically‐positive tuberculosis is continuing at 3–4 cases per 100,000 population. The highest rates were detected in males over 50 and females over 65 years of age. Three‐quarters of the total cases relate to pulmonary disease. Resistance to at least 1 anti‐tuberculosis drug was detected in 78 (12.7%) of isolates tested in 1988. The negligible decline in incidence of tuberculosis in Australia, the high prevalence in S.E. Asian countries, and the fact that HIV‐infection is an important risk factor, make it imperative that Australias diagnostic and management programmes be maintained.

Failure of Commercial Ligase Chain Reaction To Detect Mycobacterium tuberculosis DNA in Sputum Samples from a Patient with Smear-Positive Pulmonary Tuberculosis Due to a Deletion of the Target Region

ABSTRACT We report on a strain of Mycobacterium tuberculosis with a deletion in the protein antigen B gene overlapping the probe binding sites for the Abbott Diagnostics LCx M. tuberculosis (LCx-MTB) probe assay. A false-negative result with the LCx-MTB assay delayed a laboratory diagnosis of tuberculosis.

Changes of the biotype of mycobacterium avrim — mycobacterium intracellulare complex causing lung disease in Japan

A survey was carried out on the biological and biochemical characteristics of 661 strains of Mycobacterium avium-M. intracellulare complex that caused lung disease in the period 1976 to 1986. The results showed that the proportion of strains which showed 2-week-arylsulphatase activity and that of those which were able to utilize glucose as sole carbon source in the presence of glutamate-nitrogen decreased markedly, and that the proportion of those which utilized neither n-butanol nor iso-butanol as sole carbon sources in the presence of ammoniacal nitrogen increased markedly over these 11 years. These findings indicate that the predominant biotype changed from M. intracellulare to M. avium during the period under study. This postulate is supported by a limited study of the serovars present among the isolates.