Risk Factors for Multidrug-Resistant Gram-Negative Bacteria Carriage upon Admission to the Intensive Care Unit.

Multidrug-resistant Gram-negative bacteria (MDR-GNB) are microorganisms that have acquired resistance to extended-spectrum antibacterials and constitute an emerging threat to public health. Although carriers are an important source of transmission in healthcare settings, data about risk factors for MDR-GNB carriage are limited. Therefore, we aimed to identify risk factors for MDR-GNB carriage upon intensive care unit (ICU) admission and to optimise screening strategies. We conducted a case-control study. Admissions of adult patients to the ICU of a 1000-bed hospital during a year were included. We collected sociodemographic, clinical and microbiological data and performed a multivariate logistic regression model. A total of 1342 patients resulted in 1476 episodes of ICU admission, 91 (6.2%) of whom harboured MDR-GNB (38.5% women; median age 63.9 years). The most frequently isolated pathogens were Escherichia coli (57%) and Klebsiella pneumoniae (16%). The most frequent resistance mechanism was production of extended-spectrum beta lactamases. MDR-GNB carriage was associated to liver cirrhosis (OR 6.54, 95% CI 2.17-19.17), previous MDR-GNB carriage (OR 5.34, 1.55-16.60), digestive surgery (OR 2.83, 1.29-5.89) and length of hospital stay (OR 1.01 per day, 1.00-1.03). Several risk factors for MDR-GNB carriage upon admission to a high-risk setting were identified; the main comorbidity was liver cirrhosis.

Description of the largest cluster of tuberculosis notified in Norway 1997-2011: is the Norwegian tuberculosis control programme serving its purpose for high risk groups?

BACKGROUND: Approximately 90% of new tuberculosis (TB) cases notified in Norway are asylum seekers and other immigrants from high-incidence countries. Asylum seekers are screened upon arrival at the National Immigration Centre. Other immigrants receive a letter from the Municipal Health Services requesting that they present for screening in their municipality of residence. In order to identify potential areas where the TB control programme could be better adapted for these groups, we studied the largest cluster of TB cases ("cluster X") notified in Norway until 2011. METHODS: Cases were defined as TB notifications reported to MSIS between January 1997 and December 2011 with identical IS6110 RFLP assigned to cluster X. We described the cases in cluster X by using data from the Norwegian Surveillance System for Communicable Diseases (MSIS). Missing or incomplete information in MSIS was obtained from the National Reception Centre, Oslo University Hospital and Municipal Health services. RESULTS: Of a total of 44 individuals meeting the case definition, 36 originated from Somalia and eight from other high-incidence countries. Twenty nine were asylum seekers and 15 were other immigrants. Upon arrival, 18/44 had been diagnosed with latent TB infection (LTBI), 9/44 tested negative for LTBI and 4/44 had been diagnosed with active TB. Results of TB-screening upon arrival were not available for the remaining 13/44 (one asylum seeker and 12 other immigrants). Five of the 12 other immigrants had still not been screened for TB after staying one year or longer in Norway. CONCLUSIONS: Most cases in cluster X with available results of TB-screening were already infected at arrival, indicating that their disease could be due to endogenous reactivation, rather than recent transmission after arrival to Norway. TB-status upon arrival was unknown for many of the other immigrants due to lack of initial screening. The reasons why conduction of the initial screening among other immigrants is failing should be explored and methods to simplify the TB screening at arrival should be implemented.