Bronchoscopic Protected Specimen Brush and Bronchoalveolar Lavage in the Diagnosis of Bacterial Pneumonia

[Current status of fibreoptic bronchoscopy in intensive care medicine]

Flexible bronchoscopy (FB) has been of great help in the management of critically ill patients. Its safety and usefulness in the hands of experienced professionals, with the required measures of caution, has resulted in the increasingly widespread use of the technique even in unstable critical patients subjected to mechanical ventilation and with high oxygen demands. The Spanish Society of Intensive and Critical Care Medicine and Coronary Units (SEMICYUC), through its Acute Respiratory Failure (GT-IRA) and Infectious Diseases (GT-EI) Work Groups, aims to promote knowledge and standards of quality in the use of FB among all specialists in Intensive Care Medicine. Through an expert committee, the SEMICYUC has established the objective of accrediting such training, with the preparation of a curriculum and definition of those Units qualified for providing training in the different techniques and levels. The accreditation process seeks to stimulate good learning practice and quality in training. Both specialists in Intensive Care Medicine and other specialists, and the patients, will benefit from the commitment and control afforded by such accreditation, and from the learning and training which the mentioned process entails.

A prospective study of the diagnostic utility of sputum Gram stain in pneumonia

INTRODUCTION

Sputum Gram stain and culture have been said to be unreliable indicators of the microbiological diagnosis of bacterial pneumonia. The etiological diagnosis of pneumonia is surrounded by great degree of uncertainty. This uncertainty should be and can be calculated and incorporated in the diagnosis and treatment.

STUDY OBJECTIVES

To determine the diagnostic accuracy and diagnostic value of sputum Gram stain in etiological diagnosis and initial selection of antimicrobial therapy of bacterial community acquired pneumonia (CAP). DESIGN-METHOD: Prospective study of 1390 patients with CAP admitted January 2002-June 2008, to our institutions. Of the 1390 patients, 178 (12.8%) fulfilled the criteria for inclusion into this study (good-quality sputa and presence of the same microorganism in blood and sputum cultures which was used as gold standard for assessing the diagnostic accuracy and diagnostic value of sputum Gram stain).

RESULTS

The sensitivity of sputum Gram stain was 0.82 for Pneumococcal pneumonia, 0.76 for Staphylococcal pneumonia, 0.79 for Haemophilus influenzae pneumonia and 0.78 for Gram-negative bacilli pneumonia. The specificity of sputum Gram stain was 0.93 for Pneumococcal pneumonia, 0.96 for Staphylococcal pneumonia, 0.96 for H. influenzae pneumonia and 0.95 for Gram-negative bacilli pneumonia. The positive likelihood ratio (LR+) was 11.58 for Pneumococcal pneumonia, 19.38 for Staphylococcal pneumonia, 16.84 for H. influenzae pneumonia, 14.26 for Gram-negative bacilli pneumonia. The negative likelihood ratio (LR-) was 0.20 for Pneumococcal pneumonia, 0.25 for Staphylococcal pneumonia, 0.22 for H. influenzae pneumonia, and 0.23 for Gram-negative bacilli pneumonia.

CONCLUSIONS

Sputum Gram stain is a dependable diagnostic test for the early etiological diagnosis of bacterial CAP that helps in choosing orthological and appropriate initial antimicrobial therapy.

[Consensus guidelines for respiratory endoscopy issued by the Argentine Society of Bronchoesophagology]

The international consensus is that guidelines for respiratory endoscopy are inadequate, regarding such issues as institutional requirements, benefits, risks and limitations of the procedure, training programs and accreditation, with the result that the way or performing endoscopy varies according to how an operator was trained. The absence of precise recommendations means that practice is highly diverse and inappropriate use of the procedure has increased. The Argentine Consensus Group for Normalization of Respiratory Endoscopy was created in 1995 to unify criteria for several aspects of endoscopic practice. The official recommendations of the Group and of the Argentine Society of Bronchoesophagology define the indications (diagnostic, therapeutic and investigative) and contraindications (absolute, relative and high risk) for bronchoscopy. Required pre-bronchoscopic studies for routine and special cases are defined, as are indications for premedication, intubation and general anesthesia. Requirements for the setting, support personal and instruments are specified. Guidelines for topical anesthesia and techniques for insertion of the endoscope are suggested. The technique, indications and limitations of bronchoalveolar lavage, bronchial brushing and biopsy and transbronchial needle biopsy are defined. The utility and limitations of the various therapeutic techniques of bronchoscopy (laser, radiotherapy and stents) are defined. Norms to safeguard the patient, instruments and operator are emphasized.

The role of bacterial super infection in extensive pulmonary tuberculosis. Data from protected brush cultures in untreated patients from the University of South Alabama Medical Center, Mobile, Alabama, USA

Pulmonary tuberculosis (TB) and bacterial pneumonia are both characterized by fever, cough, and purulent sputum production. Although TB alone can cause these symptoms, the possibility of a concomitant bacterial pneumonia has led some clinicians to treat these patients empirically with antibacterial agents. Neither the benefit of such empiric antibiotic therapy nor transtracheal aspirate cultures from patients with pulmonary TB have yielded consistent results. Consequently, we performed a prospective study to obtain lower airway secretions via a bronchoscopic protected specimen brush (PSB) technique for quantitative aerobic and anaerobic cultures from untreated patients with extensive pulmonary TB (defined as cavitary disease or involvement of > or = 3 segments). We obtained bronchoscopic samples from 3 untreated men aged 21, 61, and 60 years with extensive pulmonary TB. There was no significant bacterial growth (aerobic or anaerobic) from the specimens obtained. These results, therefore, do not support the hypothesis that bacterial pneumonia is a common concomitant of extensive pulmonary TB.