Adult Respiratory Distress Syndrome in Patients with Severe Neutropenia

TLDR

ARDS is typically associated with neutrophil‑mediated pulmonary endothelial damage and is diagnosed by a precipitating event, bilateral infiltrates, normal wedge pressure, and hypoxemia. The study retrospectively identified ARDS cases occurring in patients with preexisting severe neutropenia. Over 2½ years, 11 neutropenic patients meeting ARDS criteria had early lung biopsies performed within seven days of respiratory distress. Histology revealed diffuse alveolar damage characteristic of ARDS but no neutrophil infiltrate, demonstrating that ARDS can develop without pulmonary neutrophil involvement.

Abstract

Most investigators believe that the pulmonary endothelial damage that is characteristic of the adult respiratory distress syndrome (ARDS) requires the action of neutrophils. In a retrospective review of patients with ARDS, we looked for cases that had developed in patients who already had neutropenia. Four clinical criteria were required for the diagnosis of ARDS: the occurrence of a precipitating event, diffuse bilateral pulmonary infiltrates on a chest x-ray film, a normal intravascular volume (as reflected by a wedge pressure of less than 18 mm Hg), and arterial hypoxemia. During 2 1/2 years, 11 patients fulfilled these clinical criteria, had severe neutropenia that antedated the onset of ARDS, and had pulmonary histologic specimens obtained during the early stages (less than seven days) of clinical respiratory distress. Five of these specimens showed diffuse alveolar damage without evidence of infectious pneumonitis (the histopathological finding characteristic of ARDS), and none had a neutrophil infiltrate. We conclude that ARDS can occur in the setting of severe neutropenia, without pulmonary neutrophil infiltration.