What do we know about Q fever in Mexico?

In Mexico, Q fever is considered a rare disease among humans and animals. From March to May of 2008, three patients were referred, from the state of Hidalgo to a tertiary-care center in Mexico City, with an acute febrile illness that was diagnosed as Q fever. We decided to undertake a cross sectional pilot study to identify cases of acute disease in this particular region and to determine the seroprevalence of Coxiella burnetii among healthy individuals with known risk factors for infection with this bacteria. Q fever was defined according to the Centers for Disease Control and Prevention criteria. All subjects were interviewed for signs and symptoms of the disease, demographic and household characteristics and occupational exposure to cattle. Blood samples were taken from hospitalized and outpatients with symptoms suggestive of Q fever, as well as from asymptomatic individuals with direct and daily exposure to cattle (slaughterers, butchers, farmers, shepherds and veterinarians) in the five municipalities. We report the occurrence of 17 cases with positive antibodies against C. burnetii in a rural area of central Mexico; eight cases had clinical criteria of acute Q fever disease. Results from this pilot study underscore the need for active surveillance programs and comprehensive studies to further define the prevalence and risk factors associated with the disease in Mexico, to know more about its clinical presentation and to characterize bacterial factors involved in its pathogenesis.

Molecular epidemiology and risk factors of bloodstream infections caused by extended-spectrum beta-lactamase-producing Klebsiella pneumoniae A case-control study.

OBJECTIVES: To study the prevalence, risk factors, outcome, and molecular epidemiology in patients with bacteremia caused by extended-spectrum beta-lactamase (ESBL)-producing Klebsiella pneumoniae (Kp) (cases), in comparison with patients with bacteremia caused by a susceptible Kp (controls). METHODS: This was a retrospective case-control study including all episodes of Kp bacteremia for the period 1993 to 2002 at a referral hospital for adults in Mexico. ESBL production was tested for by E-test. All isolates were typed by pulsed field gel electrophoresis (PFGE). A subset of isolates underwent plasmid analysis, conjugal transfer of cefotaxime resistance to Escherichia coli J53-2, isoelectric focusing bioassay, colony-blot hybridization, PCR, and sequencing. RESULTS: Of the 121 patients with bacteremia due to Kp included in the study, 17 (14.0%) had an ESBL-Kp isolate (cases). Multivariate analysis identified prior use of cephalosporins (OR 7.6, 95% CI 1.1-53.5; p=0.039) and stay in the intensive care unit (ICU; OR 5.6, 95% CI 1.1-27.9; p=0.033) as significant risk factors. No differences were observed in hospital stay or mortality after the event. Multi-drug resistance was more frequent in ESBL-Kp. There was no clonal predominance. A distinct beta-lactamase profile was identified, which included a combination of TEM-1 (pI 5.4) and SHV-5 (pI 8.2) in 13/17 ESBL-Kp isolates. Cefotaxime resistance was transferred by conjugation in 14/17 isolates with a >120-kb plasmid encoding ESBL. CONCLUSIONS: The prevalence of ESBL-Kp was found to be lower than that previously reported in Latin America. ESBL-Kp bacteremia was not associated with a worse clinical outcome. We were able to identify a plasmid-mediated horizontal dissemination over the 10-year period.

Resistencia de Mycobacterium tuberculosis en pacientes mexicanos. I. Características clínicas y factores de riesgo / Drug resistence of M. tuberculosis in Mexican patients: I. clinical manifestations and risk factors

Objetivo. Determinar las manifestaciones asociadas con la infección por M. tuberculosis resistente y la susceptibilidad antimicrobiana de aislados de pacientes mexicanos. Diseño. Vigilancia epidemiológica. Sitio. Centro de tercer nivel. Pacientes. Casos de tuberculosis confirmada. Mediciones. Resistencia primaria: cuando no hubo antecedente de tratamiento, y secundaria cuando lo hubo. Se emplearon las siguientes concentraciones críticas (µg/mL): son isoniacida 0.2 y 1; rifampicina 1 y 5; etambutol 5 y 10; estreptomicina 2 y 10; etionamida 5; kanamicina 6; y ácido paraaminosalicílio (PAS) 2 y 10. Resultados. Se incluyeron 84 pacientes con edad promedio de 44.7 años (6-80 años); 54 hombres (64 por ciento) y 30 mujeres (36 por ciento). La mayoría (35/62) del Distrito Federal y del Estado de México. Sólo en 34 pacientes se obtuvo información clínica: 26 presentaron fiebre y pérdida de peso, y ocho síntomas respiratorios. Se encontraron 59 pacientes (70 por ciento) con M. tuberculosis sensible y 25 resistente (30 por ciento). En 17 (68 por ciento) hubo resistencia a dos drogas y 16 (64 por ciento) de ellos a isoniacida y rifampicina. La tasa de resistencia global fue: isoniacida 24 por ciento, rifampicina 19 por ciento, estreptomicina 12 por ciento, etambutol 10 por ciento, PAS 9 por ciento, etianamida 7 por ciento y kanamicina 6 por ciento. En 47 pacientes sin tratamiento previo, ocho tuvieron infección por organismos resistentes (17 por ciento), y la tasa de resistencia primaria fue: isoniacida 9 por ciento, rifampicina 6 por ciento, estreptomicina 2 por ciento, etambutol 2 por ciento, PAS 6 por ciento y multirresistencia 6 por ciento. De 37 pacientes con tratamiento previo, 17 (46 por ciento) tuvieron un organismo resistente, y la tasa de resistencia secundaria fue: isoniacida 44 por ciento, rifampicina 35 por ciento, estreptomicina 24 por ciento, etambutol 19 por ciento, PAS 12 por ciento y multirresistencia 35 por ciento. Incluimos cuatro médicos con M. tuberculosis mono o multirresistente y siete pacientes con SIDA, uno de ellos con multirresistencia y otro con resistenia a isoniacida. Conclusión. Los resultados muestran tasas elevadas de resistencia a isoniacida y rifampicina, y de multirresistencia en M. tuberculosis aislado de pacientes mexicanos