Comparison of IS1245 restriction fragment length polymorphism and pulsed-field gel electrophoresis for typing clinical isolates of Mycobacterium avium subsp avium.
METHODS
Little is still known about the epidemiology and pathogenesis of Mycobacterium avium subsp avium (MASA) infection.


OBJECTIVE
Examination of the reproducibility and the stability over time of pulsed-field gel electrophoresis (PFGE) and IS1245 restriction fragment length polymorphism (IS1245-RFLP) techniques. The ability of these typing systems for differentiating clinical isolates of MASA was also assessed.


METHODS
Clinical isolates recovered from 63 patients (59 human immunodeficiency virus [HIV] positive and four HIV-negative) were studied by insertion sequence IS1245 and PFGE. For the study of in vivo and in vitro stability, strains collected over time from four patients and five strains chosen at random, respectively, were used.


RESULTS
The stability of PFGE and IS1245-RFLP in vitro was excellent. PFGE was also stable in vivo, but IS1245-RFLP patterns showed some variation. The discriminatory power of IS1245-RFLP and PFGE was 0.995 and 0.989, respectively. The cluster analysis did not reveal differences between strains recovered from HIV-negative and HIV-positive patients or between patients with colonisation, local infection or disseminated disease.


CONCLUSIONS
IS1245-RFLP and PFGE are useful tools for typing MASA strains. However, IS1245 variations in vivo may complicate the analysis of epidemiological relationships.
Garriga
X
X
Servei de Microbiologia, Hospital de la Santa Creu i Sant Pau, Barcelona, Catalonia, Spain.
Cortés
P
P
Rodríguez
P
P
March
F
F
Prats
G
G
Coll
P
P
D000328:Adult; D000368:Aged; D001483:Base Sequence; D002648:Child; D004251:DNA Transposable Elements; D016521:Electrophoresis, Gel, Pulsed-Field; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D008969:Molecular Sequence Data; D015269:Mycobacterium avium Complex / Q000145:classification* / Q000235:genetics*; D015270:Mycobacterium avium-intracellulare Infection / Q000175:diagnosis / Q000235:genetics; D016133:Polymerase Chain Reaction; D012150:Polymorphism, Restriction Fragment Length; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D012703:Serotyping / Q000379:methods; D013045:Species Specificity
D004251:DNA Transposable Elements