SPREAD OF A VIRULENT MYCOBACTERIUM TUBERCULOSIS CLINICAL ISOLATE WITH RD-RIO SIMILAR PROFILE SHOWING RESISTANCE TO REACTIVE NITROGEN INTERMEDIATE AND ISONIAZID IN RIO DE JANEIRO, BRAZIL
MARISTELA CC LIMA¹, ANDREIA LAMOGLIA¹, ERIC H ROMA¹, ANA C.C.S. LEANDRO¹, MARIA CRISTINA LOURENÇO¹, HARRISON MAGDINIER GOMES¹, PHILLIP SUFFYS¹, ANNA CRISTINA CARVALHO¹, RAPHAEL HIRATA JUNIOR¹, AFRÂNIO LINEU KRITSKI¹, MARIA DA GLORIA BONECINI ALMEIDA ¹
1. INI-FIOCRUZ - Instituto Nacional de Infectologia Evandro Chagas, 2. IOC-FIOCRUZ - Instituto Oswaldo Cruz, Fiocruz, 3. HUCFF/UFRJ - Tuberculosis Unit Research, Pneumology Service, Clementino Fraga Filho University Hospital at Federal University of Rio de Janeiro , 4. UERJ - Department of Microbiology, School of Medical Science, Rio de Janeiro State University
gloria.bonecini@ini.fiocruz.br

Mycobacterium tuberculosis infects one third of the population of the world. Almost 7 to 8 million of new cases are diagnosed, and 1.7 million of deaths are reported by year. The dissemination of clinical isolates demonstrates a great dispersion of clones, and may influence the transmission and possibly, the development of distinct clinical outcomes and vaccine efficacy. The inducible oxygen-dependent host enzyme nitric oxide synthase-2 (NOS2) counteracts microbial intruders by means of NO production and reactive nitrogen intermediate (RNI). This study aimed to evaluate the relationship among clinical isolates and their susceptibility to antimicrobial agents and the resistance to RNI in samples recovered from 1995 to 1997.   M. tuberculosis clinical isolates were collected through the clinical-epidemiological study published elsewhere between 1995 e 1997 from UFRJ and expanded. Genotyping was accessed by DNA extraction, PCR amplification and detection and sizing of 24-loci MIRU-VNTR typing and spoligotyped using a commercial kit. Conventional drugs susceptibility test was carried. Resistance to RNI was carried in vitro through incubation in sodium nitrite for 24h and CFU calculated as the percent of survival.  We observed no clone profile from 19 clinical isolates recovered from a General Hospital in Rio de Janeiro and a wide range of susceptibility to RNI ranging from 17.1 to over 100% of survival. There was an expressive concomitant resistance to anti-TB drug and RNI. Interesting, one isolate had the some RD ^Rio  profile showing moderate RNI and isoniazid resistance. These results indicate that RD ^Rio strain profile would be circulating on Rio de Janeiro several years before there identification and RNI resistance may contribute to the maintenance of this isolate spread on tuberculosis community transmission. Also, suggest that the interactions between RNI and various M. tuberculosis strain could be highly specific, since activated macrophages produce peroxynitrite, the significance of the ONOO- resistance of M. tuberculosis strains in relation to intracellular survival deserves further investigation. Thus, new insights into the pathophysiological features of the M. tuberculosis complex strains are required for development of novel vaccines and for control of MDR/XDR infection, eventually leading to refinement of treatment regimens and the health care system.