Background: Candidemia is a major infectious complication in pediatric patients. Early antifungal therapy is key to improved outcomes. Blood cultures lack sensitivity and a timely diagnosis remains difficult. Mannan is one of the mayor antigenic components of Candida spp. Several studies have reported its use for diagnosis of candidemia, but the experience in children is limited and has controversial results.
Methods: We performed a retrospective study, from January to December 2013, in a pediatric referral center to assess the utility of mannan antigen and analyze risk factors for candidemia. We included pediatric patients with blood culture and mannan antigen test (Platelia enzime immunoassay) performed in the first 48 hours from suspicion of candidemia. Patients who received antifungals in the previous 2 weeks were excluded. Patient's demographics, clinical characteristics, and laboratory results were collected from records.
Results: 92 patients were analyzed, 60% were male, mean age was 6 years, 27% had acute leukemia, 21% solid tumors, 23% congenital heart disease, 11% genetic syndromes, 8% chronic hepatopathy. Five patients had documented candidemia. According to a logistic regression model adjusted for covariates, duration of endotracheal intubation (OR 1.26 per day, CI 95% 1.05-1.51) and number of antibiotics administered during the previous 3 weeks (OR 6.05, CI 95% 1.16-31.3) were risk factors for candidemia. Mannan antigen levels varied between 0 and 600 pg/ml. The mean value in patients with and without candidemia was 314.4 pg/ml and 90.3 pg/ml respectively (p=0.004, Mann-Whitney U test). ROC curve was performed with a resulting area under the curve of 0.881 (figure 1). The threshold value that maximizes the test performance was 220 pg/ml, with sensitivity of 80% and specificity of 89%. The threshold of 125 pg/ml, as recommended by the manufacturer, drops specificity to 75% with no gain in sensitivity.
Conclusion: Duration of intubation and use of antibiotics are potentially modifiable risk factors for candidemia in our population. Mannan antigen test may contribute to the diagnosis of invasive candidiasis, and cutoff value should be revised. Findings should be confirmed in a large multicenter setting with a homogeneous population.
Figure 1: ROC curve for Mannan Antigen for diagnosis of candidemia
M. Avilés-Robles, None