PI is no longer with the University

The purpose of this study is to determine whether a protein called TREM-1 can be used to differentiate viral and bacterial pneumonias in children who are on ventilator support. We propose that the level of TREM-1 will be significantly elevated in the lung fluid of children with bacterial pneumonia and viral with co-existing bacterial pneumonia than in children with pure viral pneumonia.

Most often, viruses are the cause of pneumonia in children. However, viral pneumonias are frequently associated with secondary bacterial pneumonia. It is important, though difficult, to differentiate patients who only have viral pneumonia from those who have viral pneumonia with secondary bacterial pneumonia. This will help physicians to prescribe antibiotics to only those with bacterial pneumonia and avoid antibiotic use in those with pure viral pneumonia, thus help to limit health-care cost and to decrease emergence of antibiotic resistance. In adult studies, TREM-1 has been shown to be specifically expressed in bacterial infections.

We propose that measuring TREM-1 in the bronchoalveolar lavage (BAL) fluid will help to differentiate these groups. Our hypothesis is that concentration of TREM-1 will be significantly elevated in the BAL fluid of children with bacterial pneumonia and viral with co-existing bacterial pneumonia than in children with pure viral pneumonia.

Inclusion Criteria:

• Children from birth to 18 years intubated for respiratory failure or for surgery as mentioned above within 48 hours of intubation.

Exclusion Criteria:

• Use of antibiotics >72 hours preceding the study (not applicable to the definite bacterial pneumonia group)
• Use of oral/parenteral glucocorticoid therapy <2 weeks prior to admission
• Presence of tracheostomy
• Active treatment for pulmonary arterial hypertension
• Mechanical ventilation with FIO2 >0.6, MAP>20
• Presence of severe pulmonary interstitial emphysema, pneumothorax, bradycardia (heart rate, <80 beats/min in neonates, <70 beats/min in infants), hypotension (mean arterial pressure, <40 mm Hg in neonates, <50 mm Hg in infants), and platelet count of <30,000/mm3.
• Immunodeficient or immunocompromised due to other conditions.
• Enrollment in another interventional study that employs BAL.

Intubated patients in the intensive care unit with respiratory failure. Intubated patients patients in the OR undergoing video-assisted thoracic surgery for empyema.

Intubated patients undergoing cardiopulmonary bypass.