[Exercise performance of patients with alveolar proteinosis].
BACKGROUND
Cardiopulmonary exercise testing (CPET) is used to evaluate the severity of interstitial lung diseases, particularly when lung function is normal. The aim of this study was to analyse exercise capacity of patients with alveolar proteinosis.


METHODS
We studied 7 patients undergoing alveolar proteinosis (aged 38 +/- 5 years), Three patients complained of exertional dyspnoea, 2 had a reduced vital capacity and 5 had a DLCO of less than 75% predicted. CPET was performed on a bicycle ergometer using a standard incremental protocol.


RESULTS
CPET was symptom limited for all patients.. At peak exercise, VO2 was severely reduced (19.5 +/- 5.2 ml/kg/min, 58 +/- 9%). All patients developed hyperventilation. Ventilatory reserve was 42 +/- 11% of MMV, and dead space ratio (Vd/Vt) reached 0.29 +/- 0.05. Cardio-circulatory adaptation was normal (maximum heart rate 83 +/- 9%; VO2/heart rate 70 +/- 10%). Six patients exhibited gas exchange abnormalities at peak exercise (including 4 patients having a normal vital capacity): P(A-a)O2 56 +/- 18mm Hg; PaO2 65 +/- 18 mm Hg.


CONCLUSIONS
Patients undergoing alveolar proteinosis have severe impairment of aerobic capacity and gas exchange on exercise. CPET appears to be useful for therapeutic management.
Bautin
N
N
Clinique des maladies respiratoires, Hôpital Calmette, CHRU Lille, France.
Fournier
C
C
Marie
E
E
Robin
S
S
Neviere
R
R
Wallaert
B
B
D000222:Adaptation, Physiological; D000328:Adult; D004562:Electrocardiography; D005080:Exercise Test; D017079:Exercise Tolerance; D005260:Female; D006339:Heart Rate; D006801:Humans; D006985:Hyperventilation / Q000209:etiology; D000860:Hypoxia / Q000209:etiology; D008297:Male; D008875:Middle Aged; D010991:Plethysmography; D011649:Pulmonary Alveolar Proteinosis / Q000503:physiopathology*; D011659:Pulmonary Gas Exchange; D012016:Reference Values; D012129:Respiratory Function Tests; D012143:Respiratory Physiological Phenomena; D012146:Rest; D014797:Vital Capacity