Table 1.

Definition of IPS 4, 5

I Evidence of widespread alveolar injury: a. Multilobar infiltrates on routine chest radiographs or computed tomography b. Symptoms and signs of pneumonia (cough, dyspnea, tachypnea, rales) c. Evidence of abnormal pulmonary physiology: (1) increased alveolar to arterial oxygen difference and (2) new or increased restrictive pulmonary function test abnormality II Absence of active lower respiratory tract infection based upon: a. Bronchoalveolar lavage negative for significant bacterial pathogens including acid-fast bacilli, Nocardia, and Legionella species b. Bronchoalveolar lavage negative for pathogenic nonbacterial microorganisms: (1) routine culture for viruses and fungi, (2) shell vial culture for CMV and respiratory RSV, (3) cytology for CMV inclusions, fungi, and Pneumocystis jirovecii (carinii) and (4) direct fluorescence staining with antibodies against CMV, RSV, HSV, VZV, influenza virus, parainfluenza virus, adenovirus, and other organisms c. Other organisms/tests to also consider: (1) PCR for human metapneumovirus, rhinovirus, coronavirus, and HHV6, (2) polymerase chain reaction for chlamydia, mycoplasma, and Aspergillus species and (3) serum galactomannan ELISA for Aspergillus species d. Transbronchial biopsy if condition of the patient permits IIIAbsence of cardiac dysfunction, acute renal failure, or iatrogenic fluid overload as etiology for pulmonary dysfunction

CMV indicates cytomegalovirus; RSV, respiratory syncytial virus; HSV, herpes simplex virus; VZV, varicella zoster virus.