Effect of contact avoidance or treatment with oral prednisolone on bronchoalveolar lavage surfactant protein A levels in subjects with farmer's lung.
BACKGROUND
Surfactant protein A (SP-A) acts as an immune system modulator in the lungs and may therefore be involved in the pathogenesis of hypersensitivity pneumonitis.


METHODS
The levels of SP-A in bronchoalveolar lavage (BAL) fluid were measured in 20 subjects with acute farmer's lung, 16 asymptomatic dairy farmers, and 14 normal controls. Eight patients had a second evaluation after one month of treatment by either contact avoidance (n = 3) or oral prednisolone (20 or 25 mg/day, n = 5). Chest radiographs and lung function measurements were also obtained in all farmers, twice in those re-evaluated after treatment.


RESULTS
Patients with acute farmer's lung had significantly higher levels of SP-A than asymptomatic farmers and normal controls (p = 0.005) with mean (SE) values of 1.43 (0.29) micrograms/ml, 0.62 (0.09) microgram/ml, and 0.68 (0.11) microgram/ml, respectively. In eight subjects tested after one month of treatment the level of SP-A was unchanged although all were clinically improved. No correlations were seen between levels of SP-A in BAL fluid and numbers of BAL cells, lung function measurements, or chest radiographic scores.


CONCLUSIONS
Although the level of SP-A is increased in the BAL fluid of patients with acute farmer's lung, it is not correlated with clinical abnormalities of this disease.
Cormier
Y
Y
Unité de Recherche, Hôpital and Université Laval, Chemin Ste-Foy, Québec, Canada.
Israël-Assayag
E
E
Desmeules
M
M
Lesur
O
O
D000328:Adult; D000893:Anti-Inflammatory Agents / Q000494:pharmacology / Q000627:therapeutic use*; D001992:Bronchoalveolar Lavage Fluid / Q000737:chemistry / Q000166:cytology; D005203:Farmer's Lung / Q000000981:diagnostic imaging / Q000628:therapy*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D010758:Phosphorus / Q000032:analysis; D011239:Prednisolone / Q000494:pharmacology / Q000627:therapeutic use*; D011510:Proteolipids; D037662:Pulmonary Surfactant-Associated Protein A; D037661:Pulmonary Surfactant-Associated Proteins; D011663:Pulmonary Surfactants; D011859:Radiography; D012129:Respiratory Function Tests
D000893:Anti-Inflammatory Agents; D011510:Proteolipids; D037662:Pulmonary Surfactant-Associated Protein A; D037661:Pulmonary Surfactant-Associated Proteins; D011663:Pulmonary Surfactants; D010758:Phosphorus; D011239:Prednisolone