Factors for persistence of MRSA carriage one year after initial detection in individuals from various healthcare institutions.

INTRODUCTION AND OBJECTIVE: We studied the natural history of patients with chronic stable illnesses that are colonized by Methicillin Resistant Staphylococcus aureus (MRSA). The aim was to determine the persistence colonization 1 year after. Moreover, we intended to disclose factors that predict MRSA persistence. MATERIAL AND METHODS: A multicentric, prospective observational study was designed. Patients from an acute-care hospital and 4 long-term healthcare facilities were included. Demographic, clinical and microbiological data (nasal and skin swabs) were obtained every 3 months during a year. MRSA carriers were decolonized with nasal mupirocin. RESULTS: Among the 699 screened patients, 114 MRSA carriers were identified. MRSA carriage persisted in 59.4% of those who completed the follow-up. Baseline factors associated to MRSA persistence were heart failure, comorbidities, antibiotics, and ulcers. At one year: LTHF, underweight, Barthel<60, and ulcers (the two latest were independent predictors). Persistence was not associated to decolonization. CONCLUSION: Our study disclosed a high MRSA persistence rate and identified several associated factors (both at baseline and one year later). This information may be useful to identify individuals at high-risk of being MRSA carriers at hospital admission.

[Prosthetic joint infection: a prospective study in five Catalonian hospitals]. / Infección de prótesis articulares: estudio prospectivo en 5 hospitales de Cataluña.

BACKGROUND: Prosthetic joint infections are a cause of increasing morbidity and medical expenditure. OBJECTIVES: To determine the incidence and the clinical and the epidemiological characteristics of knee and hip prosthetic infections (PI) in patients undergoing elective surgery in five Catalonian hospitals. To determine the predictive factors of PI. METHODS: A total of 425 patients operated on between 8 January and 8 July 2001 were prospectively followed for a period of two years. The cumulative incidence, incidence rate and effect measures were determined. Logistic regression was used to identify variables associated with PI. RESULTS: Average age was 71 years and 63.1% were women. Antibiotic prophylaxis with cefazolin was given to 44.7% of the patients, with a mean duration of two days. Prophylaxis was administered during anesthesia induction in 75.6% of the patients. Among the total, 63.4% of the patients were ASA 2. Microbiological confirmation was obtained in all the infected patients; Staphylococcus epidermidis was found in 58%. Fourteen PI were diagnosed, 71% during the first 3 months, with a cumulative incidence of 3.29% and a 3-month incidence rate of 63 patients/10,000 patients/month. Diabetes mellitus was the only variable related to PI in the multivariate analysis: 3.18, 95% CI (1.1-9.9). CONCLUSIONS: The cumulative incidence of PI was slightly higher than that seen in other studies. Variations were observed in the antibiotic used for prophylaxis, and the place where it was administered. PI occurred 3.18 times more frequently in diabetic patients.

[Legionnaire's disease outbreak]. / Estudio de un brote de infección por Legionella pneumophila.

BACKGROUND AND OBJECTIVE: To describe an outbreak of Legionella pneumophila serogroup 1 in Mataró, Catalunya, Spain, in August 2002. The source of the microorganism was a cooling tower. PATIENTS AND METHOD: Prospective and observational study with analysis of epidemiological, clinical, and microbiological data. RESULTS: 151 patients were affected (62% male), with a mean age of 58.4 years old. Seven patients were classified as Pontiac Fever and 144 suffered from pneumonia. The diagnosis of pneumonia was confirmed in 79% of cases, was considered suspicious in 14% and probable in 7%. Forty per cent of patients were smokers and 53.5% had comorbidities, mainly diabetes mellitus (22%). Chief symptoms were fever (97%), chills and muscular pain (63% respectively), headache (54%) and cough (53%). Pulmonary condensation was the more frequent radiological feature (71%). Normal pulmonary exploration was observed in 38%. Forty-three per cent of cases were severely ill, and 16% of patients belonged to Fine's IV and V class. Antigenuria was the most important test for diagnosis, which confirmed 76% of cases. Legionella spp. was obtained in respiratory secretions of 10 patients. Molecular analysis confirmed clonality between respiratory microorganisms and that obtained in the cooling tower. CONCLUSION: The outbreak involved an important number of subjects in a short period of time. Antigenuria was the most useful test. However, the isolation of L. pneumophila from patients permitted the prompt identification of microorganism's source in a cooling tower. The low mortality observed probably relates to a rapid diagnosis and its target treatment.