RESUMEN
OBJECTIVE To identify risk factors related to Mycobacterium abscessus subsp. bolletii infection during an outbreak, associated with laparoscopic surgery and to propose recommendations for preventing new cases. DESIGN A retrospective cohort study. SETTING A private hospital in Manaus, Brazil. PATIENTS A cohort of 222 patients who underwent laparoscopic surgery between July 2009 and August 2010 by a single surgical team. METHODS We collected information about the patients and the surgical procedure using a standard form. We included sex, age, and variables with P≤0.2 in the bivariate analysis in a logistic regression model. Additionally, we reviewed the procedures for reprocessing the laparoscopic surgery equipment, and the strains obtained with culture were identified by molecular methods. RESULTS We recorded 60 (27%) cases of infection. After multivariate analysis, the duration of surgery beyond 1 hour (odds ratio [OR] 2.4; 95% confidence interval [CI] 1.2-4.5), not to have been the first operated patient on a given day (OR, 2.7; 95% CI, 1.4-5.2), and the use of permanent trocar (OR, 2.2; 95% CI, 1.1-4.2) were associated with infection. We observed that the surgical team attempted to sterilize the equipment in glutaraldehyde solution when sanitary authorities had already prohibited it. Eleven strains presented 100% DNA identity with a single strain, known as BRA100 clone. CONCLUSIONS Because contaminated material can act as vehicle for infection, ensuring adequate sterilization processing of video-assisted surgery equipment was crucial to stopping this single clonal outbreak of nonturbeculous mycobacteria in Brazil.
Asunto(s)
Brotes de Enfermedades , Desinfección/normas , Laparoscopía/efectos adversos , Infecciones por Mycobacterium no Tuberculosas/epidemiología , Mycobacterium chelonae , Infección de la Herida Quirúrgica/epidemiología , Adulto , Anciano , Anciano de 80 o más Años , Brasil/epidemiología , Infección Hospitalaria/epidemiología , Infección Hospitalaria/microbiología , Infección Hospitalaria/prevención & control , Procedimientos Quirúrgicos del Sistema Digestivo/efectos adversos , Procedimientos Quirúrgicos del Sistema Digestivo/instrumentación , Desinfectantes , Femenino , Glutaral , Adhesión a Directriz , Hospitales Privados , Humanos , Laparoscopía/instrumentación , Masculino , Persona de Mediana Edad , Tipificación Molecular , Infecciones por Mycobacterium no Tuberculosas/microbiología , Infecciones por Mycobacterium no Tuberculosas/prevención & control , Mycobacterium chelonae/clasificación , Mycobacterium chelonae/genética , Estudios Retrospectivos , Factores de Riesgo , Instrumentos Quirúrgicos/efectos adversos , Instrumentos Quirúrgicos/microbiología , Infección de la Herida Quirúrgica/microbiología , Infección de la Herida Quirúrgica/prevención & control , Adulto JovenRESUMEN
In Brazil, zoonotic visceral leishmaniasis (ZVL) control programs based on the mass elimination of seropositive dogs have failed to reduce the number of leishmaniasis cases. However, these programs have been done under sub-optimal conditions. We studied a cohort of dogs in an urban area in Brazil to determine, whether a dog-culling program optimized with: (i) replacement of a relatively low-sensitivity indirect immune-fluorescent test on blood eluate by a more sensitive enzyme-linked immunosorbent assay on serum blood samples; (ii) shortening of the time interval from serodiagnosis to removal of dogs; (iii) screening a high proportion of the dog population could reduce the incidence of canine Leishmania infection (CLI). The study ran from December 1997 to July 2000, with four follow-up assessments performed at approximately 8-month intervals. All dogs seropositive for anti-Leishmania antibodies were promptly eliminated. A large number of new dogs immigrated to the study area throughout the study period. They comprised 43.8-49.8% of the cohort at each follow-up assessment, and upto 15% of them already had Leishmania infection. Overall, 42 news cases of CLI were identified, for a crude incidence rate of 11.8 cases per 100 dog-years (95% CI 8.6-15.6). In the first, second, third and fourth follow-up assessments the incidence rates were 8.2 (95% CI 3.0-17.9), 12.2 (95% CI 6.3-21.2), 16.4 (95% CI 8.5-28.6) and 13.6 (95% CI 7.1-23.8), respectively. There was no statistically significant change in these rates throughout the study period. Our results suggest that dog-culling programs do not reduce the incidence of CLI, even with an optimized intervention. Possible reasons for this failure include: currently available serologic methods lack sufficient sensitivity and/or specificity to accurately identify all infected dogs warranting removal in order to prevent Leishmania transmission; destroyed dogs are immediately replaced by susceptible puppies, and quite often, by already infected dogs; and other reservoirs may be involved in maintaining canine infection. Further efforts on ZVL control should be directed to developing new strategies or to testing control methods already in place with properly designed trials.