Large, negatively charged, multilamellar liposomes were examined for their ability to improve the therapeutic activity of the broad-spectrum antiviral agent ribavirin (RIB) and the synthetic immunostimulant muramyl tripeptide (MTP-PE) in the treatment of viral pneumonitis. ARDS and pneumonia are closely related to critically ill patients; however, the etiologic agent is not always identified. The patient was initially treated at another center, but his condition deteriorated during nadroparin therapy and he was referred to our hospital. When human (SK-N-SH) or mouse (neuro-2A) neuroblastoma cells were infected with a virus that does not express LAT or AL gene products (dLAT2903), beta interferon (IFN-beta) and IFN-alpha RNA expression was detected earlier relative to the same cells infected with HSV-1 strains that express LAT and AL. HSV bronchopneumonitis was defined as this deterioration, associated with HSV in bronchoalveolar lavage and HSV-specific nuclear inclusions in cells recovered during lavage or bronchial biopsies. Prior chronic heart disease was more prevalent in non-survivors than in survivors and, at the time of HSV-1 isolation, the mean creatinine level was higher (P < 0.05) in the former. Transbronchial Biopsy Low sensitivity for bacterial infections, but an important tool for assessing rejection Wedge Lung Biopsy Considered the gold standard when less invasive procedures have not provided an adequate diagnosis. Absence of CMV detection in NPS had a negative predictive value of 98.8% for absence of CMV detection in BAL. Control subjects completed serologic tests and NPA.