Platelet activating factor and tumor necrosis factor-alpha in bronchoalveolar lavage fluid of patients with ARDS

Platelet activating factor (PAF) and tumor necrosis factor alpha (TNF-alpha) were examined in the bronchoalveolar lavage fluid (BALF) of 21 ARDS patients to clarify the role of these factors in ARDS. Neutrophil percentages and albumin concentrations in the BALF of the ARDS group were markedly elevated compared with those in the control group (p < 0.01), showing a significant correlation (r = 0.596, p < 0.01). PAF was detected in 14 of 19 ARDS patients (237.5 +/- 86.0 pg/ml) and TNF-alpha was detected in 7 of 16 ARDS patients (24.9 +/- 13.6 pg/ml), whereas these factors were not detected in control subjects. Neither PAF nor TNF-alpha showed a significant correlation with neutrophil percentage, neutrophil number or albumin concentration. They do not seem to be contributing factors to the prognosis of ARDS patients. However the existence of PAF and TNF-alpha in the BALF of some ARDS patients suggests that they might play a role in the pathogenesis of ARDS.