Invasive techniques for the diagnosis of respiratory infectious diseases

Conclusion Reviewing the history of diagnostic procedures of causative organisms of respiratory infections, invasive techniques such as the protected specimen catheter (PSB) and bronchoalveolar lavage (BAL) have become the preferred choices because they have many advantages. These methods cause the patient relatively little discomfort, and permit an early diagnosis since they can easily be performed at the bedside and the causative organism from the disease site is obtained in cultures. These procedures can be used not only in patients with community-acquired lung infections, but also in immunocompromised hosts, including those with blood diseases or following renal transplantation, in patients in intensive care units and in mechanically-ventilated patients so that the cause can be accurately determined and chemotherapy started quickly, resulting in better therapeutic efficacy. Although these invasive procedures are advantageous for the diagnosis of respiratory infections, they also present various problems which remain to be addressed including minimizing contamination and setting diagnostic threshold values. However, the importance of accurately determining the causative organism in respiratory infections should be recognized as the most important factor, and these methods have shown to date to provide the most accurate information to aid in the timely treatment of respiratory infections in a wide variety of patients.