Molecular diagnostic methods in pneumonia.

PURPOSE OF REVIEW: Molecular techniques offer the promise of improving diagnosis of lower respiratory tract infections. This review focuses on currently used molecular diagnostic techniques for various types of pneumonia and highlights potential future applications of this technology.

RECENT FINDINGS: Lower respiratory tract infections result in a high degree of morbidity and mortality, but a definitive microbiologic diagnosis is often not obtained by traditional culture or serologic methods. In addition, culture of certain organisms may be difficult or require extended periods of time. Molecular techniques have the potential to improve diagnostic yield and decrease time to pathogen identification. These techniques are also helpful in the determination of drug sensitivity and the understanding of transmission and outbreaks. Most currently used techniques employ some variation of the polymerase chain reaction. Limitations include high costs, the need for specialized equipment, and problems with false-positive and -negative results.

SUMMARY: Molecular diagnosis of pneumonia has the potential to improve identification of pathogens in patients with suspected lower respiratory tract infection. Limitations of molecular techniques currently prevent their widespread use, but future developments will likely lead to inclusion of these tests in routine diagnostic evaluations.