Incidence of Candidemia Has More Than Doubled Since 1992

Emma Hitt, PhD

July 15, 2010

July 15, 2010 (Atlanta, Georgia) — Candidemia incidence appears to have increased (as much as 3 times), as has the number of infections stemming from more resistant species, such as Candida glabrata, according to new data from the Centers for Disease Control and Prevention (CDC).

The findings were reported by Angela Ahlquist, MPH, an epidemiologist from the Mycotic Diseases Branch of the CDC, here at the International Conference on Emerging Infectious Diseases 2010.

"Healthcare technology has improved greatly since the last surveillance project was conducted in 1992 [in Atlanta, Georgia] and 2000 [in Baltimore, Maryland]," said Ms. Ahlquist. "It's possible that improvements have allowed higher-risk populations, such as organ transplant patients, to increase, and that might contribute to more infections," she told Medscape Medical News.

Previous surveillance data from Atlanta (1992–1993) and Baltimore (1998–2000) indicated a Candidemia incidence of 8.7 per 100,000 people and 24 per 100,000 for the 2 cities, respectively. The researchers conducted recent surveillance of these 2 cities beginning in 2008, and compared the 2 time periods.

Increases Reported in Atlanta and Baltimore

As of March 1, 2010, 1011 cases of Candidemia were reported in Atlanta (an incidence of 14 per 100,000 people), which is a 66% increase in the number of cases since 1993; in Baltimore, the number of cases was 683 (an incidence of 31.5 per 100,000), which is a 32% increase since 2001.

The median age of those infected was 57 years, and 51% of the infections were reported in women. Incidence in blacks was twice that observed in whites (21.5 vs 10 per 100,000; P < .0001).

Risk factors for Candidemia included the use of systemic antibacterials (80%) and total parenteral nutrition (35%) within the previous 2 weeks. Surgery (53%) and diabetes (33%) within the previous 3 months were also risk factors.

Approximately 85% of patients had a central venous catheter when Candidemia occurred; 72% of those catheters were removed within 7 days of the culture date. One in 4 patients died within 30 days of infection, and the median time to death was 9 days.

In Atlanta, the greatest increases were in C glabrata, which tripled in incidence, and Candida parapsilosis, which nearly doubled. In Baltimore, the incidence of C parapsilosis doubled.

Proper Treatment Requires Proper Identification

According to Ms. Ahlquist, the treatment and prevention of Candidemia has many challenges, one of which is properly identifying the species and then treating appropriately, because different species are susceptible to different antifungal drugs.

"Candidemia is associated with at least a 20% mortality rate, which, among the blood-borne infections, is one of the highest mortality rates," said independent commentator Peter Pappas, MD, an infectious disease specialist from the University of Alabama in Birmingham.

"Definitely No Decrease" in Candidemia

"These findings are somewhat surprising and definitely suggest there has been no decrease," he told Medscape Medical News, "but Candidemia is a disease of medical progress, and the increase may be in part related to more patients living with complications for a longer time, being instrumented more frequently, and receiving more broad-spectrum antibiotics, although this is purely speculation."

"Another issue may be better reporting of cases; we cannot exclude that as a cause of the increase," he added.

According to Dr. Pappas, the development of resistance might be driven by the widespread use of fluconazole. "There's no question that this has led to the emergence of more resistant strains, and this may be driving the emergence away from Candida albicans and toward more resistant strains," he said.

"Clinicians should be willing to choose alternatives to fluconazole," he said. "Other options are available, although they are very expensive and have to be administered intravenously."

The authors and commentator have disclosed no relevant financial relationships.

International Conference on Emerging Infectious Diseases (ICEID) 2010: Poster session 5. Presented July 12, 2010.