Study objective: To determine the features of pulmonary involvement in patients with tropical spastic paraparesis associated with human T-cell lymphotropic virus type 1.
Design: Nonrandomized prospective case series.
Setting: Tertiary care units in two university medical centers.
Patients: Consecutive sample of 21 patients with tropical spastic paraparesis associated with human T-cell lymphotropic virus type 1 infection.
Interventions: Chest roentgenogram and bronchoalveolar lavage were done in all patients. Fifteen patients had pulmonary function tests. Alveolar T-lymphocyte subsets were analysed in 10 patients and thoracic computed tomographic scans were done in 10 patients.
Measurements and main results: All patients were free of clinical pulmonary symptoms and had normal chest roentgenograms. Thoracic computed tomographic scans were normal in 9 of 10 patients and showed mild interstitial pneumonitis in 1. Pulmonary function tests were within the normal range in 13 patients and showed a mild restrictive syndrome in 2. Eighteen patients had increased absolute numbers of alveolar lymphocytes (mean, 77 +/- 39 X 10(3) lymphocytes/mL; range, 13.5 X 10(3) to 259 X 10(3) lymphocytes/mL). Sixteen patients had percentages of alveolar lymphocytes higher than 20% of all alveolar cells (mean, 33.5 +/- 12.7; range, 9 to 69). In all 10 patients tested, 64.2% +/- 13.2% of alveolar lymphocytes were CD8+ cells.
Conclusions: Excessive absolute numbers and percentages of alveolar lymphocytes were observed in 18 and 16 patients, respectively. Most alveolar lymphocytes were CD8+ cells.