title: Nontuberculous mycobacterial lung disease in patients without HIV infection: a retrospective analysis over 3 years.
abstract: BACKGROUND
  Nontuberculous mycobacterial lung infections are relatively common in immunocompromised patients but are now increasingly being diagnosed in immunocompetent individuals. These organisms are not always pathogenic bacteria when isolated from human samples. The identification of which isolates are contaminants or colonizers is based on internationally accepted criteria. The clinical significance of the isolation of nontuberculous mycobacteria (NTM) from respiratory specimens in Italy is unknown.
  
  
  OBJECTIVE
  study was performed to evaluate the local epidemiology of NTM pulmonary infection in Naples in patients with positive respiratory specimens, and also to describe the clinical and radiological features of NTM pulmonary disease in immunocompetent patients with or without pre-existing lung disease.
  
  
  METHODS
  Between December 2006 and September 2009, the clinical records and radiological examinations of 39 patients with 55 positive cultures for NTM species by sputum or bronchial wash or lavage were reviewed.
  
  
  RESULTS
  According to microbiological, clinical and radiological criteria, our study identified 16 patients with NTM lung infection as a 'disease' group and 23 patients in a 'contamination' group but without disease. M. intracellulare (n = 7, 41.2%), followed by M. kansasii (n = 5, 29.4%) were the most common NTM found in the 'disease' group. We detected a high number of M. gordonae isolates in respiratory samples obtained by fibrobronchoscopy.
  
  
  CONCLUSIONS
  We evaluated the clinical significance of isolations in our reference centre in Naples. Forty-one of all patients have 'disease', M. intracellulare and M. kansasii are mainly responsible. NTM species were analyzed in relation to their frequency. Assumptions were made about low pathogenic NTM isolations.
authors.affiliation: Department of Cardio-Thoracic and Respiratory Sciences, Second University of Naples, Monaldi Hospital, Naples, Italy. ginevradelgiudice@gmail.com
authors.forename: Ginevra
authors.initials: G
authors.lastname: Del Giudice
authors.forename: Carlo
authors.initials: C
authors.lastname: Iadevaia
authors.forename: Giulia
authors.initials: G
authors.lastname: Santoro
authors.forename: Emilio
authors.initials: E
authors.lastname: Moscariello
authors.forename: Riccardo
authors.initials: R
authors.lastname: Smeraglia
authors.forename: Carlo
authors.initials: C
authors.lastname: Marzo
mesh_terms: D000368:Aged; D005260:Female; D006801:Humans; D007121:Immunocompetence; D007558:Italy / Q000453:epidemiology; D008297:Male; D008875:Middle Aged; D009165:Mycobacterium Infections, Nontuberculous / Q000453:epidemiology* / Q000276:immunology / Q000382:microbiology; D014397:Tuberculosis, Pulmonary / Q000453:epidemiology* / Q000276:immunology / Q000382:microbiology