title: Genetic diversity among Mycobacterium avium complex strains recovered from children with and without human immunodeficiency virus infection.
abstract: The genetic diversity and molecular epidemiology of Mycobacterium avium complex (MAC) infections in children with and without human immunodeficiency virus (HIV) infection were evaluated. Isolates recovered from 136 children were subtyped by sequence analysis of a 360-bp region of the gene (hsp65) encoding a 65-kDa heat-shock protein. Twenty-one distinct hsp65 alleles were identified. On the basis of hsp65 genotype, 6 isolates were not MAC organisms. Of the remaining 130 samples, 61% were M. avium, 37% were Mycobacterium intracellulare, and 2% were species nonspecific MAC. Eighty-eight percent of the isolates obtained from HIV-infected children were M. avium. In contrast, only 38% of the isolates obtained from children without HIV infection were M. avium (chi2 test, P < .001). M. avium isolates were further subtyped by Southern blot analysis with insertion element IS1245. Taken together, no evidence for a single clonal M. avium strain causing infection was detected.
authors.affiliation: Department of Pediatrics, and Institute for the Study of Human Bacterial Pathogenesis, Baylor College of Medicine, Houston, Texas 77030, USA.
authors.forename: D S
authors.initials: DS
authors.lastname: Swanson
authors.forename: X
authors.initials: X
authors.lastname: Pan
authors.forename: M W
authors.initials: MW
authors.lastname: Kline
authors.forename: R E
authors.initials: RE
authors.lastname: McKinney
authors.forename: R
authors.initials: R
authors.lastname: Yogev
authors.forename: L L
authors.initials: LL
authors.lastname: Lewis
authors.forename: M T
authors.initials: MT
authors.lastname: Brady
authors.forename: G D
authors.initials: GD
authors.lastname: McSherry
authors.forename: W M
authors.initials: WM
authors.lastname: Dankner
authors.forename: J M
authors.initials: JM
authors.lastname: Musser
mesh_terms: D017088:AIDS-Related Opportunistic Infections / Q000453:epidemiology / Q000382:microbiology*; D000293:Adolescent; D000483:Alleles; D001426:Bacterial Proteins / Q000235:genetics*; D001483:Base Sequence; D018834:Chaperonin 60; D018833:Chaperonins / Q000235:genetics*; D002648:Child; D002675:Child, Preschool; D004251:DNA Transposable Elements; D004269:DNA, Bacterial; D014644:Genetic Variation; D006801:Humans; D007223:Infant; D008969:Molecular Sequence Data; D009162:Mycobacterium avium / Q000145:classification / Q000235:genetics; D015269:Mycobacterium avium Complex / Q000145:classification / Q000235:genetics* / Q000302:isolation & purification; D015270:Mycobacterium avium-intracellulare Infection / Q000453:epidemiology / Q000382:microbiology*; D010802:Phylogeny
chemical_list: D001426:Bacterial Proteins; D018834:Chaperonin 60; D004251:DNA Transposable Elements; D004269:DNA, Bacterial; C074119:heat-shock protein 65, Mycobacterium; D018833:Chaperonins