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Procalcitonin in children admitted to hospital with community acquired pneumonia
F Moulin1, J Raymond, M Lorrot
1Department of Pediatrics, Hôpital Saint Vincent de Paul, 82 Av Denfert-Rochereau, 75014 Paris, France.
Insights
Procalcitonin (PCT) effectively distinguishes bacterial from viral pneumonia in children. PCT offers higher accuracy than C-reactive protein (CRP) and other markers for diagnosing pneumonia causes.
Area of Science:
- Pediatric Infectious Diseases
- Clinical Biochemistry
- Respiratory Medicine
Background:
- Community-acquired pneumonia (CAP) diagnosis in children can be challenging.
- Differentiating bacterial from viral etiologies is crucial for appropriate antibiotic stewardship.
- Biomarkers like procalcitonin (PCT) and C-reactive protein (CRP) are used to aid diagnosis.
Purpose of the Study:
- To evaluate the diagnostic performance of procalcitonin (PCT) compared to CRP, interleukin-6 (IL-6), and leukocyte count.
- To determine the sensitivity, specificity, and predictive values of PCT in differentiating bacterial and viral pneumonia in children.
Main Methods:
- A cohort of 72 children with community-acquired pneumonia was studied.
- Procalcitonin (PCT), C-reactive protein (CRP), and leukocyte counts were measured.
- Interleukin-6 (IL-6) levels were assessed when available.
- Diagnostic accuracy was compared against confirmed bacterial or viral pneumonia, including blood cultures and sputum analysis.
Main Results:
- Procalcitonin (PCT) levels above 1 microg/l were observed in 86% of bacterial pneumonia cases.
- PCT demonstrated higher specificity (86%) than CRP (40%) in distinguishing bacterial from viral pneumonia.
- PCT levels were significantly higher in bacteremic pneumonia compared to non-bacteremic or viral pneumonia.
Conclusions:
- Procalcitonin (PCT) is a sensitive and specific biomarker for differentiating bacterial from viral community-acquired pneumonia in children.
- A PCT threshold of 1 microg/l offers superior diagnostic value over CRP, IL-6, and leukocyte count.
- PCT aids in guiding antibiotic therapy decisions for pediatric pneumonia.
Aims:
To assess the sensitivity, specificity, and predictive value of procalcitonin (PCT) in differentiating bacterial and viral causes of pneumonia.
Methods:
A total of 72 children with community acquired pneumonia were studied. Ten had positive blood culture for Streptococcus pneumoniae and 15 had bacterial pneumonia according to sputum analysis (S pneumoniae in 15, Haemophilus influenzae b in one). Ten patients had Mycoplasma pneumoniae infection and 37 were infected with viruses, eight of whom had viral infection plus bacterial coinfection. PCT concentration was compared to C reactive protein (CRP) concentration and leucocyte count, and, if samples were available, interleukin 6 (IL-6) concentration.
Results:
PCT concentration was greater than 2 microg/l in all 10 patients with blood culture positive for S pneumoniae; in eight of these, CRP concentration was above 60 mg/l. PCT concentration was greater than 1 microg/l in 86% of patients with bacterial infection (including Mycoplasma and bacterial superinfection of viral pneumonia). A CRP concentration of 20 mg/l had a similar sensitivity but a much lower specificity than PCT (40% v 86%) for discriminating between bacterial and viral causes of pneumonia. PCT concentration was significantly higher in cases of bacterial pneumonia with positive blood culture whereas CRP concentration was not. Specificity and sensitivity were lower for leucocyte count and IL-6 concentration.
Conclusions:
PCT concentration, with a threshold of 1 microg/l is more sensitive and specific and has greater positive and negative predictive values than CRP, IL-6, or white blood cell count for differentiating bacterial and viral causes of community pneumonia in untreated children admitted to hospital as emergency cases.
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