The evaluation of MRSA surveillance cultures by the number and combinations of anatomical sites
Article Category: Original scientific article
Published Online: Jul 28, 2016
Page range: 24 - 30
Received: Nov 27, 2015
Accepted: May 31, 2016
DOI: https://doi.org/10.1515/sjph-2017-0004
Keywords
© National Institute of Public Health, Slovenia
This work is licensed under the Creative Commons Attribution-NonCommercial-NoDerivatives 3.0 License.
Introduction
The identification of patients infected and/or colonised by methicillin resistant
Methods
All surveillance samples, which were sent for a microbiological analysis to detect MRSA with the culture method in 2014, in the three departments for medical microbiology of the National Laboratory for Health, Environment and Food, were included in this study.
Results
Among 65,251 surveillance cultures from 13,274 persons, 1,233 (2.1%) were positive (490 positive persons). Prevailing positive surveillance cultures were throat swabs (31.3%), followed by nose swab (31.2%), skin swab (18.9%), perineum (16.4%) and wound swabs (1.4%). The contribution of other samples, such as aspirate, urine and excreta, was under 1%. We found no statistically significant differences in the frequency of detection of a positive patient, if the combination of samples NTS (nose, throat, skin) or NTP (nose, throat, perineum) was analysed. However, statistically significant differences were confirmed when any of the anatomic sites would be omitted from the sets of NTP and NTS (chi square; p<0.01). Adding additional samples resulted in only 24 additional positive patients (4.9%).
Conclusions
The results indicate that increasing the number of surveillance cultures above three does not add much to the sensitivity of MRSA surveillance, the exception could be wound. The swabs from the perineum and from the skin are exchangeable.