RAPID DIAGNOSIS OF BACTERIAL PNEUMONIA AGENTS WITH REAL TIME MULTIPLEX PCR

BAHAR AKGÜN KARAPINAR, CIHAN YEŞILOĞLU, NEZAHAT GÜRLER

Department of Medical Microbiology, İstanbul Faculty of Medicine, İstanbul University, İstanbul

Introduction: Community acquired pneumonia (CAP) is a common infectious disease that is associated with high treatment costs and mortality rates that vary between 4% and 50%. Culture and serological tests are the most commonly used means of determining of the etiology of CAP, although no agents are identified in almost 50% of cases. Polymerase chain reaction (PCR) methods developed in recent years allow for both the rapid diagnosis and identification of the causative agent in up to 87% of cases. In the present study, we investigate bacterial CAP agents in pleura fluid samples obtained from pleuritic patients based on no growth in cultures.

Materials and methods: Clinical samples were investigated using conventional culture methods and Gram staining. The causative agents in the samples with no growth on culture results were identified using a QIAamp DNA mini kit (Qiagen, Germany) for bacterial DNA isolation, and a Multiplex Real-Time PCR method (FTD Bacterial pneumonia-CAP, Fast Track Diagnostics, Luxemburg) to determine the causative agents.

Results: In this study, 89 patients’ clinical samples were studied, from which Chlamydia pneumoniae (n: 2), Legionella pneumoniae (n: 2), Haemophilus influenzae (n: 2) and Streptococcus pneumoniae (n: 1) species were isolated. Moraxella catarrhalis and Mycoplasma pneumonia species were also investigated, but not isolated in any patient.

Conclusion: Conventional methods may not always sufficient to detect pneumonia agents. The Multiplex Real-Time PCR method ensures a rapid and more sensitive diagnosis than culture, and allows the selection of agent-targeted treatments, con- tributing to a shortening of hospital stays, and consequently, preventing such potential drawbacks as nosocomial infections and the development of antibiotic resistance.