Pulmonary arterial hypertension and severe pulmonary fibrosis in systemic sclerosis patients with a nucleolar antibody.

OBJECTIVE: Pulmonary arterial hypertension (PAH) and severe pulmonary fibrosis (SPF) are the most common causes of death in scleroderma. Our study focuses on lung disease in patients with a nucleolar antibody in comparison to other scleroderma-specific autoantibodies.
METHODS: Patients initially seen between 1972 and 1995 (and followed through 2004) with [systolic pulmonary artery pressure (sPAH) (PASP > 50 mm Hg] or SPF [forced vital capacity (FVC%) < 55% predicted) were grouped by the presence of anticentromere antibody (ACA), an isolated antinucleolar antibody (ANoA), or an antitopoisomerase antibody-I (TOPO).
RESULTS: Twenty percent of ACA, 23% of TOPO, and 32% of ANoA patients had severe lung disease (p < 0.005). In ANoA patients with PAH without severe fibrosis, the FVC was lower (71% predicted) than in ACA patients, suggesting they had some interstitial fibrosis. However, they had a higher FVC%/diffusing capacity for carbon monoxide (DLCO)% ratio than the ACA patients (2.4 vs 1.8). pulmonary hypertension in TOPO patients was associated with a lower FVC%/DLCO% ratio and lower levels of PAP than either the PAH in ACA or ANoA patients.
CONCLUSION: Scleroderma-specific autoantibodies are associated with characteristic subgroups of lung disease. The ANoA patients have a unique mixture of PAH and SPF subgroups of lung disease. Scleroderma-specific autoantibodies and the FVC%/DLCO% ratio are helpful in determining whether a patient has PAH alone, PAH along with pulmonary fibrosis, or secondary PAH from chronic hypoxia with SPF.