Multidrug-Resistance and C. difficile Rates in Hospitals

In This Article

Abstract and Introduction

Abstract

We surveyed infection prevention programs in 16 hospitals for hospital-associated methicillin-resistant Staphylococcus aureus (MRSA), vancomycin-resistant enterococci, extended-spectrum β-lactamase, and multidrug-resistant Acinetobacter acquisition, as well as hospital-associated MRSA bacteremia and Clostridium difficile infection based on defining events as occurring >2 days versus >3 days after admission. The former resulted in significantly higher median rates, ranging from 6.76% to 45.07% higher

Introduction

The Centers for Disease Control and Prevention (CDC) has long-standing guidance that hospital-associated infections (HAIs) usually become evident 48 hours after admission.^[1] Based on this guidance, hospitals had built differing definitions to indicate HAIs. We previously reported that an approximately equal proportion of hospitals defined HAIs as (1) onset after 48 hours from admission, (2) onset >2 calendar days after admission, and (3) onset >3 calendar days after admission.^[2]

While choice of definition is less important for intrafacility comparisons over time, the national movement toward interfacility benchmarking (eg, state public reporting laws, Centers for Medicare and Medicaid Services Hospital Inpatient Quality Reporting) can make comparisons problematic when data are collected in different ways. Furthermore, since hospital lengths of stay are, on average, 4.8 days, the inclusion of an additional day for hospital-associated event surveillance can substantially affects rates.^[3]

In January 2013, CDC redefined hospital-associated events as having an onset of >2 calendar days from admission for all HAI modules (except the multidrug-resistant organisms [MDROs] laboratory module, which adds to the confusion by using a more conservative definition of >3 calendar days since it relies solely on microbiology data).^[4] It would be valuable to understand the magnitude of effect that this change in surveillance may have on hospital rates. We therefore performed a multicenter evaluation to quantify the impact of using a >2-calendar-day versus a >3-calendar-day rule to define MDRO acquisition and MDRO and Clostridium difficile infection.

Table 1. Impact of Using >2-Day versus >3-Day Case Finding Definitions for Hospital-Associated Acquisition and Infection Events View table image
Pathogen	Median hospital-associated rate using >2-day definition (events/10,000 total patient-days)	Median hospital-associated rate using >3-day definition (events/10,000 total patient-days)	Wilcoxon signed-rank test P value	Increase in median rate when using >2-day versus >3-day definition, %
Acquisition
MRSA	7.16	5.21	.001	27.21
VRE^a	2.24	2.01	.016	10.53
ESBL^b	0.54	0.50	.001	6.76
MDR Acinetobacter	0.87	0.80	.078	8.96
Infection
MRSA bacteremia	0.30	0.17	.031	45.07
Clostridium difficile infection	6.00	4.79	.001	20.14

Note. ESBL, extended-spectrum β-lactamase; MDR, multidrug resistant; MRSA, methicillin-resistant Staphylococcus aureus; VRE, vancomycin-resistant enterococci.
^aData from 15 hospitals; other data from 16 hospitals.
^bESBL is Klebsiella and Escherichia coli combined.