USE OF MICROSCOPIC MORPHOLOGY IN SMEARS PREPARED FROM RADIOMETRIC CULTURES FOR PRESUMPTIVE IDENTIFICATION OF MYCOBACTERIUM-TUBERCULOSIS COMPLEX, MYCOBACTERIUM-AVIUM COMPLEX, MYCOBACTERIUM-KANSASII, AND MYCOBACTERIUM-XENOPI

Citation
J. Gonzalez et al., USE OF MICROSCOPIC MORPHOLOGY IN SMEARS PREPARED FROM RADIOMETRIC CULTURES FOR PRESUMPTIVE IDENTIFICATION OF MYCOBACTERIUM-TUBERCULOSIS COMPLEX, MYCOBACTERIUM-AVIUM COMPLEX, MYCOBACTERIUM-KANSASII, AND MYCOBACTERIUM-XENOPI, European journal of clinical microbiology & infectious diseases, 17(7), 1998, pp. 493-500
Citations number
12
Categorie Soggetti
Microbiology,"Infectious Diseases
ISSN journal
09349723
Volume
17
Issue
7
Year of publication
1998
Pages
493 - 500
Database
ISI
SICI code
0934-9723(1998)17:7<493:UOMMIS>2.0.ZU;2-K
Abstract
The aim of this study was to assess the feasibility of a method for pr esumptive identification of mycobacteria? based on the morphology in s mears prepared from radiometric Bactec-positive cultures (Becton Dicki nson, USA) and to select the appropriate DNA probe (AccuProbe; Gen Pro be, USA). The smear morphology of acid-fast bacilli was evaluated in 4 68 positive cultures from clinical samples: 313 Mycobacterium tubercul osis complex, 67 Mycobacterium avium complex, 32 Mycobacterium kansasi i, 49 Mycobacterium xenopi, and seven Mycobacterium gordonae. The sens itivity and specificity for various morphological patterns were as fol lows: cord formation for Mycobacterium tuberculosis complex 90% and 10 0%, respectively; striped bacilli for Mycobacterium kansasii, 66% and 99%; sea urchin for Mycobacterium xenopi, 96% and 99%; short bacilli f or Mycobacterium avium complex, 61% and 99%; fine-striped bacilli asso ciated with Mycobacterium avium complex from blood samples, 33% and 98 %. This criterion was applied in the selection of a suitable DNA probe for the identification of 178 cultures. The correct probe was selecte d in 98%, 97%, and 72% of cultures, respectively, for Mycobacterium tu berculosis complex, Mycobacterium avium complex, and Mycobacterium kan sasii. The observation of acid-fast bacilli morphology in radiometric cultures is a rapid and cost-efficient method for presumptive identifi cation of common clinical isolates of mycobacteria.