Evaluation of the polymerase chain reaction method for detection of Streptococcus pneumoniae DNA in pleural fluid samples.

Abstract

STUDY OBJECTIVE:

Streptococcus pneumoniae is the most frequent causative agent of community-acquired pneumonia (CAP); however, an etiologic diagnosis by traditional techniques can be accomplished in only a small percentage of patients with CAP. Pleural fluid is present in approximately 40% of patients with CAP; therefore, we hypothesized that detection of S pneumoniae DNA in pleural fluid by polymerase chain reaction (PCR) may help to increase the rate of diagnosis of pneumococcal pneumonia.

DESIGN:

A prospective study of cases.

SETTING:

A university hospital in Lleida, Spain.

PATIENTS AND METHODS:

One hundred two samples of pleural fluid (51 samples from consecutive adult patients with pneumonia and 51 samples from unselected control subjects) were tested by the nested-PCR method to detect selected pneumolysin gene of S pneumoniae, and the results were compared with those provided by alternative diagnostic methods.

RESULTS:

PCR in pleural fluid had a diagnostic sensitivity of 78% in patients with pneumococcal pneumonia, with positive results in 2 of 2 patients (100%) and 5 of 7 patients (71%) who had positive or negative pleural fluid culture findings, respectively. PCR results were also positive in 3 of 24 patients (12%) with pneumonia of unknown etiology and negative in all patients with pneumonia due to microorganisms other than S pneumoniae. Thus, the calculated specificity was 93%. Among control subjects, PCR gave positive results in two cases (4%).

CONCLUSION:

The nested-PCR test, applied to pleural fluid samples from patients with CAP, showed a sensitivity of 78% and a specificity of 93% in the diagnosis of pneumococcal pneumonia.

• Authors: Miquel Falguera, Aurora López, Antoni Nogués, José Manuel Porcel, Manuel Rubio-Caballero
• Journal: Chest (Chest) Vol. 122 Issue 6 Pg. 2212-6 (Dec 2002) ISSN: 0012-3692 [Print] United States
• PMID: 12475865 (Publication Type: Evaluation Study, Journal Article)

Chemical References

• DNA, Bacterial

Topics

• Adolescent
• Adult
• Aged
• Aged, 80 and over
• Community-Acquired Infections (microbiology)
• DNA, Bacterial (analysis)
• Female
• Humans
• Male
• Middle Aged
• Pleural Effusion (chemistry)
• Pneumonia, Bacterial (microbiology)
• Polymerase Chain Reaction
• Prospective Studies
• Sensitivity and Specificity
• Streptococcus pneumoniae (genetics)