National surveillance of fungemia in Denmark (2004 to 2009)

Abstract

A 6-year nationwide study of fungemia in Denmark was performed using data from an active fungemia surveillance program and from laboratory information systems in nonparticipating regions. A total of 2,820 episodes of fungemia were recorded. The incidence increased from 2004 to 2007 (7.7 to 9.6/100,000) and decreased slightly from 2008 to 2009 (8.7 to 8.6/100,000). The highest incidences were seen at the extremes of age (i.e., 11.3 and 37.1/100,000 for those <1 and 70 to 79 years old, respectively). The rate was higher for males than for females (10.1 versus 7.6/100,000, P = 0.003), with the largest difference observed for patients >50 years of age. The species distribution varied significantly by both age and gender. Candida species accounted for 98% of the pathogens, and C. albicans was predominant, although the proportion decreased (64.4% to 53.2%, P < 0.0001). C. glabrata ranked second, and the proportion increased (16.5% to 25.9%, P = 0.003). C. glabrata was more common in adults and females than in children and males, whereas C. tropicalis was more common in males (P = 0.020). C. krusei was a rare isolate (4.1%) except at one university hospital. Acquired resistance to amphotericin and echinocandins was rare. However, resistance to fluconazole (MIC of >4 μg/ml) occurred in C. albicans (7/1,183 [0.6%]), C. dubliniensis (2/65 [3.1%]), C. parapsilosis (5/83 [6.0%]), and C. tropicalis (7/104 [6.7%]). Overall, 70.8% of fungemia isolates were fully fluconazole susceptible, but the proportion decreased (79.7% to 68.9%, P = 0.02). The study confirmed an incidence rate of fungemia in Denmark three times higher than those in other Nordic countries and identified marked differences related to age and gender. Decreased susceptibility to fluconazole was frequent and increasing.

FIG. 1.

Geographical uptake area of the 14 participating centers designated by the following numbers: 1, Rigshospitalet; 2, Copenhagen city hospitals; 3, Copenhagen county; 4, Frederiksborg; 5, Roskilde; 6 and 7, SW-Sealand; 8, Funen; 9, S-Jutland; 10, Esbjerg; 11, Vejle; 12, Herning; 13, Viborg; 14, N-Jutland; and 15, Aarhus. The island Bornholm, 16, was served by Roskilde, 5, in 2004 but in the rest of the period by Copenhagen city hospitals, 2. No other laboratories process blood cultures in Denmark. (Adapted from a map available on Wikipedia under a Creative Commons license.)

FIG. 2.

Annual incidence of fungemia, by age and gender, in Denmark from 2004 to 2009. *, P = 0.0003; **, P < 0.0001.

FIG. 3.

Proportion of isolates for which fluconazole MIC was >2 μg/ml, by species and year. C. albicans, solid line with solid diamonds; C. dubliniensis, solid line with open diamonds; C. glabrata, solid line with open triangles; C. krusei, solid line with solid squares; C. parapsilosis, solid line with open circles; C. tropicalis, solid line with solid triangles; and all isolates, dotted line with crosses.

FIG. 4.

Consumption of systemic antifungal compounds in Denmark between 2000 and 2009 (in DDD) (a) and for fluconazole by gender and age group (mean no. of treated people per 1,000 inhabitants, 2005 to 2009) (b).