What is the Candida score?

What is the Candida Score?

The Candida score is a clinical prediction tool developed to identify critically ill patients at high risk for invasive candidiasis by combining clinical risk factors with colonization status, using a point-based system where a cutoff value ≥3 indicates patients who may benefit from empirical antifungal therapy. 1

Score Components and Calculation

The Candida score assigns points based on the following risk factors 1:

• Surgery (recent major surgery, particularly abdominal): 1 point
• Multifocal Candida colonization: 1 point
• Total parenteral nutrition (TPN): 1 point
• Severe sepsis/clinical sepsis: 2 points

The total score ranges from 0 to 5 points, with a cutoff value of ≥2.5 (typically rounded to ≥3 in clinical practice) demonstrating sensitivity of 81% and specificity of 74% for predicting invasive candidiasis. 1

Clinical Performance and Validation

The score was originally developed in 2006 by a Spanish group using the Estudio de Prevalencia de CANdidiasis database, with subsequent validation in 2009 demonstrating a significant linear association between increasing score values and rates of invasive Candida infections 1.

Prospective validation studies have confirmed that patients with scores ≤3 have extremely low rates of invasive candidiasis (0%), while those with scores of 4 or 5 have substantially higher rates (17.6% and 50%, respectively). 2

Key Performance Characteristics:

• Negative predictive value: 84-96% across validation studies 3
• Positive predictive value: 25-47% (relatively poor) 3
• Area under ROC curve: 0.66-0.72 in external validation studies 3, 4

Clinical Application and Limitations

The Candida score is most useful for ruling out invasive candidiasis rather than confirming it, given its high negative predictive value but poor positive predictive value. 3 This makes it particularly valuable for identifying patients who do not require empirical antifungal therapy, thereby avoiding unnecessary antifungal use and associated costs 1.

Important Caveats:

• The score has high specificity but low sensitivity, meaning it may miss some patients with invasive candidiasis 1
• Performance may be limited in certain populations, including COVID-19 patients where one study found no difference in Candida scores between those with and without candidemia 1
• The score performs better when combined with biomarkers such as β-D-glucan (BDG), with one study showing that an integrated strategy using both Candida score >3 and BDG helped optimize antifungal therapy decisions without increasing mortality 1

Target Population

The Candida score is specifically designed for non-neutropenic critically ill patients in the ICU setting, particularly those with hospital-acquired severe sepsis or septic shock. 2 It is not validated for neutropenic patients or those outside the ICU environment 5.

Risk Stratification:

• Score 0-2: Low risk - invasive candidiasis highly improbable 2
• Score 3-4: Moderate risk - consider additional diagnostic testing 4
• Score ≥5: High risk - strong consideration for empirical antifungal therapy 2

Integration with Other Diagnostic Approaches

While the Candida score provides clinical guidance, it should ideally be combined with non-culture diagnostic methods such as β-D-glucan testing (sensitivity 56-93%, specificity 71-100%) or mannan/anti-mannan antibody assays (combined sensitivity 83%, specificity 86%) to improve diagnostic accuracy 1. Blood cultures remain the gold standard but are negative in up to 50% of invasive candidiasis cases, highlighting the need for complementary diagnostic strategies 1.

The score has been superseded by newer prediction models in some contexts, with one recent study developing a risk score incorporating CD8+ T-cell counts that demonstrated superior performance (AUROC 0.820 versus 0.711 for Candida score alone) 4.