Study objective: To examine whether increased urinary
cysteinyl-leukotriene E4 (LTE4) excretion,
which has been found to be elevated in patients presenting with
high-altitude pulmonary edema (HAPE), precedes edema formation.
Design: Prospective studies in a total of 12 subjects with
susceptibility to HAPE.
Setting: In a chamber study,
seven subjects susceptible to HAPE and five nonsusceptible control
subjects were exposed for 24 h to an altitude of 450 m
(control day), and exposed for 20 h to 4,000 m after slow
decompression over 4 h. In a field study, prospective measurements
at low and high altitude were performed in five subjects developing
HAPE at 4,559 m.
Participants: Mountaineers with a
radiographically documented history of HAPE and control subjects who
did not develop HAPE with identical high-altitude exposure.
Interventions: 24-h urine collections.
Measurements and results: In the hypobaric chamber, none of
the subjects developed HAPE. The 24-h urinary LTE4 did not
differ between HAPE susceptible and control subjects, nor between
hypoxia and normoxic control day. In the field study, urinary
LTE4 was not increased in subjects with HAPE compared to
values obtained prior to HAPE at high altitude and during 2 control
days at low altitude.
Conclusions: These data do not
provide evidence that cysteinyl–leukotriene-mediated inflammatory
response is associated with HAPE susceptibility or the development of
HAPE within the context of our studies.