RATIONALE: Pulmonary lymphangioleiomyomatosis is a progressive cystic lung 
disease that is associated with infiltration of atypical smooth muscle-like 
cells. Previous descriptions of clinical characteristics of subjects with 
lymphangioleiomyomatosis have been based on a limited number of patients.
OBJECTIVES: To describe the clinical characteristics of subjects with pulmonary 
lymphangioleiomyomatosis, both sporadic and tuberous sclerosis-related forms.
METHODS: Over a 3-yr period, from 1998 to 2001, 243 subjects with pulmonary 
lymphangioleiomyomatosis were enrolled into a national registry; 13 subjects who 
had already undergone lung transplantation were excluded for the purposes of 
this report.
MEASUREMENTS AND MAIN RESULTS: All 230 subjects were women, aged 18 to 76 yr 
(mean +/- SE, 44.5 +/- 0.65 yr). The average age at onset of symptoms was 38.9 
+/- 0.73 yr and at diagnosis was 41.0 +/- 0.65 yr. Tuberous sclerosis complex 
was present in 14.8% of subjects. Pulmonary manifestations, most commonly 
spontaneous pneumothorax, were the primary events leading to the diagnosis in 
86.5% of cases. Nearly 55% of the subjects were being treated with a 
progesterone derivative. An obstructive pattern on pulmonary function testing 
was observed in 57.3% of the subjects, whereas 33.9% had normal spirometric 
results. Women with tuberous sclerosis-related lymphangioleiomyomatosis were 
younger and had less impaired lung function compared with those with the 
sporadic form.
CONCLUSIONS: The age range of women afflicted with pulmonary 
lymphangioleiomyomatosis is broader than previously appreciated and the degree 
of pulmonary function can be quite variable, with one-third of subjects having 
normal spirometry at enrollment into this registry.