title: Prevalence of resistance to anti-tuberculosis drugs: results of the 1998/99 national survey in Italy.
abstract: OBJECTIVE
  To determine the prevalence of resistance to the main anti-tuberculosis drugs in newly and previously treated tuberculosis patients in Italy and to evaluate the contribution of foreign-born and human immunodeficiency virus (HIV) positive cases to drug resistance.
  
  
  METHODS
  Methods and definitions were derived from the WHO/IUATLD Global Project on Anti-tuberculosis Drug Resistance Surveillance. Univariate and multivariate analysis was used to study prevalence rates of drug resistance in risk groups.
  
  
  RESULTS
  In a national survey in Italy, 810 initial isolates of Mycobacterium tuberculosis (683 from new cases, 115 from retreatment cases and 12 from patients whose treatment history was unknown/dubious) were analysed. Low prevalence of drug and multidrug resistance was found in the new cases (isoniazid 2.9%; rifampicin 0.8%; multidrug resistance 1.2%; any drug resistance 12.3%). The prevalence of resistance to isoniazid and rifampicin was significantly higher in immigrants and HIV-positive subjects, respectively. A high prevalence of drug resistance was found in cases with previous treatment failure or default (isoniazid 5.2%; rifampicin 4.3%; multidrug resistance 36.5%; any drug resistance 61.7%).
  
  
  CONCLUSIONS
  Special efforts are necessary to monitor trends in drug resistance and to ensure favourable treatment outcomes among immigrants and HIV-positive tuberculosis cases.
authors.affiliation: WHO Collaborating Centre for Control of Tuberculosis and Lung Diseases in Europe Department of Pnuemology, Tradate, Italy. gbmigliori@fsm.it
authors.forename: G B
authors.initials: GB
authors.lastname: Migliori
authors.forename: L
authors.initials: L
authors.lastname: Fattorini
authors.forename: P
authors.initials: P
authors.lastname: Vaccarino
authors.forename: G
authors.initials: G
authors.lastname: Besozzi
authors.forename: C
authors.initials: C
authors.lastname: Saltini
authors.forename: G
authors.initials: G
authors.lastname: Orefici
authors.forename: E
authors.initials: E
authors.lastname: Iona
authors.forename: A
authors.initials: A
authors.lastname: Matteelli
authors.forename: F
authors.initials: F
authors.lastname: Fiorentini
authors.forename: L R
authors.initials: LR
authors.lastname: Codecasa
authors.forename: L
authors.initials: L
authors.lastname: Casali
authors.forename: A
authors.initials: A
authors.lastname: Cassone
mesh_terms: D000995:Antitubercular Agents / Q000627:therapeutic use*; D016009:Chi-Square Distribution; D004359:Drug Therapy, Combination; D005260:Female; D006801:Humans; D007558:Italy / Q000453:epidemiology; D008297:Male; D015995:Prevalence; D018709:Statistics, Nonparametric; D018088:Tuberculosis, Multidrug-Resistant / Q000188:drug therapy / Q000453:epidemiology*
chemical_list: D000995:Antitubercular Agents