SAN DIEGO—Bacteremia may be the most important identifiable independent risk factor for candidemia among hemodialysis (HD) patients, a new study suggests. It is unclear, however, whether the associated with bacteremia is attributable to antibiotic administration or the overall level of immune dysfunction in HD patients.
Among HD patients with bacteremia, a heightened clinical suspicion for the development of candidemia clearly is warranted, said lead investigator Rhonda Colombo, MD, Assistant Professor of Infectious Diseases at Georgia Health Science University in Augusta.
“We need to raise awareness of what is posing a risk and then we may be able to go even further and explore how we can change that risk,” Dr. Colombo said.
She and her colleagues found that total parenteral nutrition (TPN) and Candida colonization were significantly associated with a 2.9 times and 2.5 times increased risk of being diagnosed with candidemia, respectively, in adjusted analyses. Most striking, they noted, was that bacteremia was associated with a greater than sevenfold increased risk of candidemia, even after adjusting for other comorbidities.
“Since this is a retrospective cohort, we weren’t able to investigate how to prevent candidemia. So we can’t make strong recommendations based on these data, but those are certainly questions that have been raised and need to be evaluated in further studies,” Dr. Colombo said.
The investigators looked at all incident HD cases from the U.S. Renal Data System (USRDS) for calendar years 2005-2008. They queried for a diagnosis of candidemia, bacteremia, and several potential clinical covariates using ICD-9 diagnosis codes submitted for Medicare billing. A total of 362,799 patients were available for analysis during the four-year study period. The median age of the patients was 65 years and 56% were male. The group was 65% Caucasian and 29% African-American.
In the USRDS cohort, candidemia was diagnosed in 304 cases per 100,000 patients annually during the study period. That contrasts sharply with the 30 cases per 100,000 adults in the U.S. Nationwide Inpatient Sample from 2000, a non-ESRD specific cohort.
The researchers identified candidemia in 1,102 (0.3%) patients and bacteremia in 70,567 (19%). Their analyses revealed that female gender and African-American race were associated with a significantly greater risk for candidemia (increased by 28% and 29%, respectively). In addition, the researchers found that HD vascular access type affected candidemia risk, with catheters and grafts associated with greater risk than arteriovenous fistulas.