TRANSMISSION BETWEEN HIV-INFECTED PATIENTS OF MULTIDRUG-RESISTANT TUBERCULOSIS CAUSED BY MYCOBACTERIUM-BOVIS

Objective: To investigate outbreaks of multidrug-resistant tuberculosi s (TB) by using DNA fingerprint databases. Design: Investigation of tw o outbreaks of multidrug-resistant TB in separate hospitals in Spain b y restriction fragment length polymorphism (RFLP) and spoligotyping. O utbreak strains were compared with more than 1500 RFLPs of Mycobacteri um tuberculosis complex strains isolated in Spain and 6000 RFLPs from 30 different countries. Methods: Standardized IS6110 DNA fingerprintin g and 'spoligotyping' was used to type multidrug-resistant isolates be longing to the M. tuberculosis complex amongst the outbreak cases. The DNA types were matched against DNA fingerprint databases in Spain and The Netherlands. Results: The DNA typing analysis indicated that a si ngle multidrug-resistant Mycobacterium bovis strain was responsible fo r a nosocomial outbreak in a hospital in Spain involving at least 16 H IV-infected patients with non-treatable to multidrug-resistant TB. Int roduction of the fingerprint type of this strain to the international database revealed a single matching strain. This strain was also isola ted from an HIV-infected patient in The Netherlands who had died from multidrug-resistant TB. This patient had previously been hospitalized in Spain, where a multidrug-resistant TB nosocomial outbreak involving 20 HIV-infected patients was ongoing. The strains causing this outbre ak were also identified as M. bovis with an identical DNA pattern to t hose strains isolated in the Spanish hospital and the patient in The N etherlands. Conclusions: The use of centralized DNA databases can help to identify rapidly the origin and transmission routes of multidrug-r esistant TB across international boundaries and the potential use of s uch an early warning surveillance system for investigation of nosocomi al multidrug-resistant TB outbreaks between HIV-infected patients. To our knowledge this is the first report of transmission of multidrug-re sistant M. bovis between hospitals.