[Factors associated with Clostridium difficile disease in a tertiary-care medical institution in Mexico: a case-control study]. / Factores asociados con el desarrollo de la enfermedad por Clostridium difficile en un hospital de tercer nivel en México: estudio de casos y controles.

INTRODUCTION: Clostridium difficile-associated disease (CDAD) has been clearly associated with the use of broad-spectrum antibiotics worldwide. However, information about CDAD is scarce in Mexico and Latin America. MATERIAL AND METHODS: We studied clinical characteristics, associated factors and outcomes of all cases of CDAD diagnosed by toxin A fecal detection in a tertiary care hospital in Mexico City from 2003 to 2007. Cases were paired with controls by date of hospital discharge. RESULTS. A total of 3170 tests were performed; we evaluated 113 cases and 226 controls, with an incidence of 5.04 cases x 1000 hospital discharges during the study period. There was no difference in gender or primary diagnosis. After multivariate analysis, we found as significant risks the following: use of H2 blockers (OR 21.73, 95% CI 7.14-66.67, p < 0.001), age < 65 y (OR 10.21, IC95% 2.74-38.00, p < 0.001), prior hospitalization within 12 weeks of diagnosis (OR 4.39, IC95% 1.81-40.64, p < 0.001), prior use of cephalosporins (OR 3.41, CI 95% 1.56-7.46, p = 0.002), and fluoroquinolones (OR 3.11, IC95% 1.12-8.62, p = 0.029), stay at the intensive care unit (ICU) (OR 2.76, IC95% 1.38-5.49, p = 0.004); and, extended hospital stay (OR 1.10, IC95% 1.05-1.16, p < 0.001) or antimicrobial use before diagnosis (OR 1.05, IC95% 1.01-1.09, p = 0.010). We described an outbreak of 12 cases occurred in August of 2005 (29.5 cases per 1,000 discharges). We also observed a higher seasonal incidence of disease during the summer in the study period. CONCLUSIONS: The use of H2 blockers, age < 65 years, prior hospitalization or earlier use of cephalosporins or fluoroquinolones, as well as stay at the ICU were independent risk factor for CDAD.

[Endemic intravenous fluid contamination in pediatric wards]. / Contaminación endémica de soluciones parenterales en servicios pediátricos.

OBJECTIVE: To determine the rate of contamination of intravenous solutions and injection ports in pediatric patients. MATERIAL AND METHODS: During non-epidemic periods, eight pediatric wards in Mexican hospitals were studied. Qualitative cultures were performed from the surface of injection ports and from intravenous solutions in use in pediatric patients younger than 2 years, culturing 750 infusion systems from 728 patients. RESULTS: The rate of contamination of intravenous solutions was 2.4% (18/750; CI 95%: 1.3% to 3.5%) and for injection ports it was 3.2% (24/750; CI 95%: 2.1% to 4.3%). Enterobacteriaceae predominated; in four cases the organisms isolated from the port and from the solutions were coincident (Klebsiella spp. and Enterobacter sp.). The rate of contamination for solutions mixed in the wards was 5.1%, against 1.3% of those not mixed (chi2 = 9.19, p < 0.01). DISCUSSION: Contamination of parenteral solutions is not a rare phenomenon and it could be related to inappropriate practices in the preparation of intravenous solutions and medications as well as the contamination of injection ports. In hospitals working with standards similar to those reported here, the monitoring of sterility of intravenous solutions could contribute to reduce the rate of nosocomial bacteremia.

[Diabetic foot microbiology through biopsy cultures]. / Microbiología del pie diabético determinada por estudio de biopsia.

OBJECTIVE: To determine the microbiology of diabetic foot wounds, through biopsy cultures. MATERIALS AND METHODS: Patients with diabetic foot and clinical data of infection were recruited consecutively. Cultures were processed for aerobic organisms after mortar homogenization. For cases with multiple isolates, only the two predominant organisms were identified. The bacterial identification was carried out by biochemical procedures. The sensitivity to antibiotics was made by the disk diffusion method. RESULTS: A total of 91 biopsies were studied, 47 from men (52%). There were 102 isolates, 68 being Gram-negative bacilli (67%), with predominance of Escherichia coli (21%). A total of 28 Gram-positive cocci were isolated (28%) and 6 yeasts (6%). Of the 68 Gram-negative bacilli, 24 were resistant to ciprofloxacin (35%). A total of 55 Enterobacteriaceae were isolated, of which 4 (7%) produced extended-spectrum beta-lactamases. There were 8 Staphylococcus aureus isolates, 3 of which (38%) were resistant to methicillin. CONCLUSIONS: In comparison with reports from industrialized countries, we found a higher proportion of Gram-negative and resistant organisms.

[Methicillin-resistant Staphylococcus aureus at a general hospital: epidemiological overview between 2000-2007]. / Staphylococcus aureus resistente a meticilina en un hospital general: panorama epidemiológico del 2000 al 2007.

INTRODUCTION: The high prevalence of methicillin-resistant Staphylococcus aureus (MRSA) in hospitalized patients is a significant problem due to its associated morbidity and mortality. It is important to know the recent MRSA epidemiology at a General Hospital. OBJECTIVES: To determine the MRSA epidemiology at a Mexican general hospital from 2000 to 2007, in order to know if there is a significant trend in its proportion. MATERIAL AND METHODS: Prevalence survey. The resistance to oxacillin was identified by the Kirby-Bauer's method. The specimens were classified by type and year of isolation. Trend statistics were used for analysis. RESULTS: S. aureus was identified in 1,008 samples, being 301 resistant to oxacillin (30%, 95% Confidence Interval [CI], 25 to 35%). The proportion of MRSA went from 37% (95% CI, 29 to 44%) to 49% (95% CI, 40 to 58%) in the period of study (chi2 for trends = 6.676, p < 0.01). Specimens with the highest proportion of MRSA were blood and sterile liquids with 32% (95% CI, 26 to 39%), secretions with 29% (95% CI, 24 to 33%), and catheters with 21% (95% CI, 16 to 26%). CONCLUSIONS: The proportion of MRSA has increased significantly. This leads to higher costs and morbi-mortality for the hospitalized patients. We require stricter policies to prevent transmission and to control the use of antibiotics.