Phenotypic and molecular characterization of three clinical isolates of Mycobacterium interjectum.
Introduction of molecular biology-based technology into an Australian mycobacterial reference laboratory has resulted in the identification of three isolates of Mycobacterium interjectum in the past 12 months. Conventional phenotypic methods failed to identify the species of these isolates, and high-performance liquid chromatography found that only one of the three isolates had a mycolic acid pattern similar to that of the type strain. In contrast, all three isolates were rapidly identified as M. interjectum by 16S rRNA gene sequence analysis. Two isolates were recovered from the lymph nodes of children with cervical lymphadenitis, confirming the pathogenicity of this organism. However, the third isolate was obtained from the sputum of an elderly male with chronic lung disease without evidence of clinical or radiological progression, suggesting that isolation of M. interjectum should not imply disease. With the increasing use of molecular biology-based technology in mycobacterial laboratories, M. interjectum may be recognized more frequently as a pathogen or commensal organism.
Lumb
R
R
Infectious Diseases Laboratories, Institute of Medical and Veterinary Science, Adelaide, South Australia.
Goodwin
A
A
Ratcliff
R
R
Stapledon
R
R
Holland
A
A
Bastian
I
I
D000368:Aged; D000995:Antitubercular Agents / Q000627:therapeutic use; D001315:Australia; D001483:Base Sequence; D002675:Child, Preschool; D002851:Chromatography, High Pressure Liquid; D005260:Female; D006801:Humans; D008198:Lymph Nodes / Q000382:microbiology; D008199:Lymphadenitis / Q000382:microbiology*; D008297:Male; D008969:Molecular Sequence Data; D009161:Mycobacterium / Q000145:classification / Q000235:genetics* / Q000302:isolation & purification*; D009164:Mycobacterium Infections / Q000175:diagnosis* / Q000188:drug therapy; D009169:Mycobacterium tuberculosis / Q000235:genetics; D009171:Mycolic Acids / Q000032:analysis; D010641:Phenotype; D012336:RNA, Ribosomal, 16S / Q000235:genetics; D016415:Sequence Alignment; D012689:Sequence Homology, Nucleic Acid; D013183:Sputum / Q000382:microbiology
D000995:Antitubercular Agents; D009171:Mycolic Acids; D012336:RNA, Ribosomal, 16S