Patients at higher risk for methicillin resistant Staphylococcus aureus than the general population.
SAN DIEGO—In dialysis patients, invasive methicillin-resistant Staphylococcus aureus (MRSA) infections occur much more frequently than in the general population, a study found.
In addition, dialysis patients more often present with uncomplicated bacteremia as compared to patients with renal insufficiency not on dialysis, researchers reported.
Therefore heightened vigilance and improved prevention strategies are needed in the dialysis population. Additional studies are needed to characterize risk factors and incidence of invasive MRSA in all CKD patients.
“We were surprised to learn just how high the risk is for these patients,” said lead investigator Cynthia Lucero, MD, an epidemic intelligence service officer at the Centers for Disease Control and Prevention (CDC) in Atlanta.
“Physicians were already aware that dialysis patients are at increased risk for MRSA infection; however, the magnitude of the increased risk was a bit surprising.” The number of dialysis centers treating patients with MRSA rose from 40% to 76% between 1995 and 2002, Dr. Lucero said. She presented findings here at the annual meeting of the Infectious Diseases Society of America.
For this study, she and her colleagues obtained surveillance data from the CDC’s Active Bacterial Core surveillance (ABCs) system. The ABCs system is a population-based surveillance for invasive pathogens, including MRSA, covering 23 counties in eight states (California, Colorado, Georgia, Maryland, Minnesota, New York, Oregon, and Tennessee), as well as the entire state of Connecticut.
From July 2004 through June 2006, 2,130 cases of invasive MRSA in dialysis patients and 1,189 cases in renal insufficiency patients were reported. Almost all patients required hospitalization and more than half in each group had diabetes. In addition, compared with nondialysis patients who had renal insufficiency, dialysis patients were more likely to have recurrent invasive MRSA infection (27% vs. 13%) and more likely to have any history of MRSA infection or colonization (35% vs. 24%). Renal insufficiency patients had higher in-hospital mortality rates (25% vs. 17%).
Additionally, the study found that dialysis patients were more likely to have an invasive device (86% vs. 38%), including central venous catheters (70% vs. 19%), making them more likely to present with bacteremia (86% vs. 77%) and uncomplicated bacteremias (63% vs. 46%).
Overall, the incidence of invasive MRSA in dialysis patients for 2005 was estimated to be 45.3 cases per 1,000 dialysis patients, a 100-fold higher risk than for the general population. Also, the incidence among dialysis patients was higher in children (54.1 per 1,000) compared with other age groups and among blacks (53.2 per 1,000) when compared with whites (32.7 per 1,000).
Among the 2,130 dialysis patients, 1,229 (58%) were male, 1,494 (70%) were aged 50 and older, 1,208 (57%) were black, and 1,220 (57%) were diabetic. Among the 1,189 patients with renal insufficiency, 767 (65%) were male, 1,030 (87%) were age 50 or older, 355 (30%) were black, and 659 (55%) were diabetic.