Isolated diffusing capacity reduction in systemic sclerosis

Wiley - Tập 35 Số 7 - Trang 765-770 - 1992
Virginia Steen1, Galen E. Graham2, Claudia Conte2, Gregory R. Owens2, Thomas A. Medsger2
1Department of Medicine, University of Pittsburgh, School of Medicine, Pennsylvania
2Department of Medicine, Divisions of Rheumatology and Clinical Immunology and Pulmonary Medicine, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania.

Tóm tắt

AbstractObjective. To determine the long‐term outcome of patients with systemic sclerosis (SSc) and an isolated reduction in the diffusing capacity for carbon monoxide (DLco) at the time of initial evaluation.Methods. Patients with an isolated reduction in DLco (i.e., normal forced vital capacity [FVC] and normal ratio of the forced expiratory volume in one second [FEV1] to the FVC) on initial evaluation were identified from among 815 patients with SSc who were carefully followed up throughout their illness. We requested that patients have repeat pulmonary function testing (PFT), and the outcomes of these tests, as well as cardiopulmonary and survival outcomes, were determined.Results. An isolated reduction in DLco, with a normal FVC was detected in 152 (19%) of the 815 patients. A subset of those with an isolated reduction in DLco (11%) developed isolated pulmonary hypertension and had severely reduced survival rates. Pulmonary hypertension was strongly associated with an initial DLco of < 55% of predicted normal and a FVC (% predicted)/DLco (% predicted) ratio of > 1.4. Among all patients in whom this ratio was > 1.4, 22% developed isolated pulmonary hypertension, compared with only 2% of those whose ratio was <1.4 (P < 0.01). Of the 152 patients with isolated DLco reduction, 73 (48%) underwent PFTs a mean of 5.4 years (range 2.0–13.2) after the initial PFT. Only 6 (8%) of these 73 patients ever had serious pulmonary disease: 5 had isolated pulmonary hypertension, and 1 had severe pulmonary fibrosis. Half of the patients with a low initial DLco demonstrated a significant improvement (>20%) at followup testing that could not be explained by the demographic, clinical, or laboratory findings at the first visit.Conclusion. Isolated reduction in DLco is a frequent abnormality in SSc. Overall, it is associated with a good prognosis for survival and for pulmonary morbidity. A small subset of patients (11%) who have a very low DLco (<55% of predicted) have developed isolated pulmonary hypertension, all of whom had limited scleroderma.

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Tài liệu tham khảo

10.1378/chest.84.5.546

10.1016/0002-9343(64)90162-7

10.1002/art.1780290409

10.1001/archinte.132.4.506

10.1016/0002-9343(82)90732-X

Kanner R, 1975, Clinical Pulmonary Function Testing: A Manual of Uniform Laboratory Procedures for the Intermountain Area

Burrows B, 1961, Clinical usefulness of single‐breath pulmonary diffusing capacity test, Am Rev Respir Dis, 84, 789

10.1002/art.1780230510

Le Roy EC, 1988, Scleroderma (systemic sclerosis): classification subsets and pathogenesis (editorial), J Rheumatol, 15, 202

Friedman LM, 1981, Fundamentals of Clinical Trials

10.1002/art.1780280706

10.1378/chest.54.6.490

10.1002/art.1780200506

10.1136/thx.18.1.10

10.1002/art.1780310207

10.1016/0002-9343(83)91169-5

10.1097/00005792-198407000-00004

10.1136/thx.34.2.224

10.1002/art.1780280807

10.1016/0002-9343(87)90501-8