Anne Piette

Role of coagulase-negative staphylococci in human disease.

Coagulase-negative staphylococci (CNS) are normal inhabitants of human skin and mucous membranes. They have long been dismissed as culture contaminants, but now the potentially important role of CNS as pathogens and their increasing incidence has been recognized. Approximately 55-75% of nosocomial isolates is methicillin resistant. CNS were the first organisms in which glycopeptide resistance was recognized. In the immunocompetent host, CNS endocarditis and urinary tract infections with Staphylococcus saprophyticus are the most common CNS infections. Other patients are usually immunocompromised, with indwelling or implanted foreign bodies. CNS account for approximately 30% of all nosocomial blood stream infections. The majority of these concern catheter-related sepsis. Other important infections due to CNS include central nervous system shunt infections, endophthalmitis, surgical site infections, peritonitis in patients with continuous ambulatory peritoneal dialysis and foreign body infections. CNS are rarely associated with mastitis in humans. Staphylococcus lugdunensis is more pathogenic than other CNS as it expresses several potential virulence factors. The distinction between clinically significant, pathogenic and contaminating isolates is a major problem. Several studies show clonal intra and inter hospital spread of Staphylococcus epidermidis strains which suggests that infection control measures may be necessary for multiresistant CNS isolates as for methicillin resistant Staphylococcus aureus. As a result of medical progress, mainly due to the use of invasive and indwelling medical devices, CNS are now a major cause of nosocomial and health-care related infections.

Epidemiology and outcome of nosocomial bloodstream infection in elderly critically ill patients: a comparison between middle-aged, old, and very old patients

Background:We investigated the epidemiology of nosocomial bloodstream infection in elderly intensive care unit (ICU) patients. Methods:In a single-center, historical cohort study (1992–2006), we compared middle-aged (45–64 years; n = 524), old (65–74 years; n = 326), and very old ICU patients (≥75 years; n = 134) who developed a nosocomial bloodstream infection during their ICU stay. Results:Although the total number of ICU admissions (patients aged ≥45 years) decreased by ∼10%, the number of very old patients increased by 33% between the periods 1992–1996 and 2002–2006. The prevalence of bloodstream infection (per 1,000 ICU admissions) increased significantly over time among old (p = 0.001) and very old patients (p = 0.002), but not among middle-aged patients (p = 0.232). Yet, this trend could not be confirmed with the incidence data expressed per 1,000 patient days (p > 0.05). Among patients with bloodstream infection, the proportion of very old patients increased significantly with time from 7.2% (1992–1996) to 13.5% (1997–2001) and 17.4% (2002–2006) (p < 0.001). The incidence of bloodstream infection (per 1000 patient days) decreased with age: 8.4‰ in middle-aged, 5.5‰ in old, and 4.6‰ in very old patients (p < 0.001). Mortality rates increased with age: 42.9%, 49.1%, and 56.0% for middle-aged, old, and very old patients, respectively (p = 0.015). Regression analysis revealed that the adjusted relationship with mortality was borderline significant for old age (hazard ratio, 1.2; 95% confidence interval, 1.0–1.5) and significant for very old age (hazard ratio, 1.8; 95% confidence interval, 1.4–2.4). Conclusion:Over the past 15 years, an increasing number of elderly patients were admitted to our ICU. The incidence of nosocomial bloodstream infection is lower among very old ICU patients when compared to middle-aged and old patients. Yet, the adverse impact of this infection is higher in very old patients.

Kolmogorov–Smirnov statistical test for analysis of ZAP-70 expression in B-CLL, compared with quantitative PCR and IgVH mutation status

ZAP‐70 has been proposed as a surrogate marker for immunoglobulin heavy‐chain variable region (IgVH) mutation status, which is known as a prognostic marker in B‐cell chronic lymphocytic leukemia (CLL). The flow cytometric analysis of ZAP‐70 suffers from difficulties in standardization and interpretation. We applied the Kolmogorov–Smirnov (KS) statistical test to make analysis more straightforward.

Destructive otomastoiditis by MRSA from porcine origin.

A 63‐year‐old female pig farmer was referred to our department with a protracted course of otomastoiditis with destruction of the tympanic roof and cerebrospinal fluid leakage. The patient underwent a cortical mastoidectomy with closure of a large dural defect. Cultures of the middle ear effusion yielded a methicillin‐resistant Staphylococcus aureus (MRSA), which upon further analysis was found to be from porcine origin. To our knowledge, this is the first report of a complicated case of otomastoiditis caused by a pig‐type MRSA. Laryngoscope, 119:137–140, 2009

Replacement of Administration Sets Used to Administer Blood, Blood Products, or Lipid Emulsions for the Prevention of Central Line-Associated Bloodstream Infection

To the Editor—Given our particular interest in the field of evidence-based guidelines for infection prevention, 1-3 we were delighted to welcome the publication of the journal’s October 2008 Supplement 1, which contained a compendium of strategies to prevent healthcare-associated infections in acute care hospitals. Indeed, in addition to supplying the healthcare worker with a very useful and excellent update of the existing recommendations, this compendium provides enlightening information regarding implementation strategies and performance measures for internal and external reporting. The paper’s executive summary states that the updated recommendations are not meant to supplant the existing, more-detailed guideline documents but aim to provide practical guidance. 4 Nevertheless, while reading the guidelines for the prevention of central line–associated bloodstream infections, 5 some questions arose. Therefore, we gratefully take this opportunity to address these questions, which concern the management of intravenous administration sets, and we thank the authors in advance for their interest and clarification. The article by Marschall et al. 5 recommends replacement