Bennett N, RN, MPH, PhD1, Johnson SA, BSc, MPH1, Smith M, RN2, Worth LJ, MBBS, FRACP, Grad Dip Epi, PhD1,3
1 Victorian Healthcare Associated Infection Surveillance System (VICNISS) Coordinating Centre, Elizabeth St, Melbourne, Victoria, 3000 Noleen.Bennett@mh.org.au.
2 Department of Health, Grampians Region, 21 McLachlan Street, Horsham, Victoria, 3400
3 Department of Medicine, University of Melbourne, Parkville, Victoria, 3010
To standardise the identification of HAIs within residential aged care facilities (RACF), McGeer et al (1991) published surveillance definitions specific to these facilities. These were revised in 2012, including new requirements for clinical and microbiologic criteria to fulfil the case-definition for urinary tract infections (UTI). For residents with and without an indwelling catheter a positive urine culture must now be reported.
In 2014, 112 Victorian RACFs participated in a point prevalence study (PPS) that evaluated the impact of the revised McGeer case definition for UTI. Presumed and confirmed UTI were classified according to three case definitions:
A: Clinical and microbiologic criteria met,
B: Clinical (not microbiologic) criteria met, and
C: Microbiologic (not clinical) criteria met.
The estimated prevalence of UTI was influenced significantly by the surveillance case definition employed. Case definition A accounted only for 35% of all reported UTI. Of those that fulfilled the clinical criteria alone (case definition B) 54% did not undergo microbiological testing. As a composite clinical measure, combining case definitions A and B resulted in an estimated crude prevalence of 3.6%.
Given the low uptake of microbiologic testing in Australian RACFs it may be beneficial for future PPS to measure the utility of microbiologic testing and incorporate assessment of clinically significant HAIs to ensure UTI are not under-estimated.