A prediction model for real-time PCR results in blood samples from febrile patients with suspected sepsis

Christian Leli1, Angela Cardaccia1, Francesco D'Alò1

  • 1Microbiology Section, Department of Experimental Medicine and Biochemical Sciences, University of Perugia, Perugia, Italy.

Insights

This study developed a prediction model to identify sepsis patients likely to have a positive SeptiFast (SF) test. The model uses procalcitonin (PCT) and other clinical factors to improve diagnostic efficiency for sepsis.

Area of Science:

  • Clinical Microbiology
  • Infectious Diseases
  • Diagnostic Medicine

Background:

  • Sepsis is a life-threatening condition requiring rapid diagnosis and treatment.
  • SeptiFast (SF) offers rapid DNA detection but has limitations in sensitivity and cost.
  • Efficient patient selection for SF testing is crucial.

Purpose of the Study:

  • To develop a predictive model for identifying febrile patients with a high probability of positive SeptiFast (SF) results.
  • To optimize the use of the SF assay by restricting it to clinically relevant cases.
  • To improve the diagnostic workflow for sepsis.

Main Methods:

  • A prediction model was developed using data from 285 febrile patients.
  • Key predictors identified included time to blood sampling, serum procalcitonin (PCT), body temperature, serum albumin, and white blood cell count.
  • Model performance was evaluated using calibration and area under the receiver operating characteristic curve (AUC).

Main Results:

  • The prevalence of positive SF results was 17.2%.
  • Independent predictors of positive SF results were identified: early blood sampling (<12h), elevated PCT (≥0.5 ng/ml), fever (≥38°C), low albumin (≤3 g/dl), and high WBC count (≥13,000/mm³).
  • The prediction model demonstrated good calibration and a high AUC (0.944), indicating strong predictive accuracy.

Conclusions:

  • A prediction model incorporating PCT and routine clinical/laboratory variables can effectively identify patients likely to have positive SF results.
  • This model can aid in selecting appropriate candidates for the SF assay, potentially reducing costs and improving diagnostic yield.
  • The findings support the use of this model to enhance the efficiency of sepsis pathogen detection.