Published ahead of print on January 17, 2008, doi:10.1164/rccm.200708-1271OC Am. J. Respir. Crit. Care Med., Volume 177, Number 7, April 2008, 752-762 A more recent version of this article appeared on April 1, 2008
Submitted on August 29, 2007 Characteristics of a Large Cohort of Autoimmune Pulmonary Alveolar Proteinosis Patients in JapanYoshikazu Inoue1,1 Department of Diffuse Lung Diseases and Respiratory Failure, National Hospital Organization (NHO) Kinki-Chuo Chest Medical Center, Clinical Research Center, Osaka, Japan, 2 Children's Hospital Research Foundation, Divisions of Pulmonary Biology and Medicine, Cincinnati, OH, USA, 3 Tohoku University, Institute of Development, Aging, and Cancer, Sendai, Japan, 4 Niigata University Medical and Dental Hospital, Niigata, Japan, 5 Tsukuba University Hospital, Tsukuba, Japan, 6 Department of Respirology, Graduate School of Medicine, Chiba University, Chiba, Japan, 7 International Medical Center of Japan, Division of Respiratory Medicine, Tokyo, Japan, 8 Dokkyo University Koshigaya Hospital, Koshigaya, Japan, 9 Chofu Hospital, Tokyo, Japan, 10 Department of Medicine, Aichi Medical University School of Medicine, Division of Respiratory Medicine and Allergology, Aichi, Japan, 11 NHO Sanyo Hospital, Ube, Japan, 12 Osaka University, Research Institute for Microbial Diseases, Osaka, Japan, 13 Nagasaki University, Institute of Tropical Medicine, Nagasaki, Japan, 14 University of South Florida, Tampa, FL, USA * To whom correspondence should be addressed. E-mail: radical{at}med.niigata-u.ac.jp.
Rationale: Acquired pulmonary alveolar proteinosis (PAP) is a syndrome characterized by pulmonary surfactant accumulation occurring in association GM-CSF autoantibodies (autoimmune PAP) or as a consequence of another disease (secondary PAP). Because PAP is rare, prior reports were based on limited patient numbers or synthesis of historical data. Objectives: To describe the epidemiological, clinical, physiological and laboratory features of autoimmune PAP in a large, contemporaneous cohort of PAP patients. Methods: Over 6 years, 248 PAP patients were enrolled into a Japanese national registry, including 223 with autoimmune PAP (focus of this report). Measurements and Main Results: Autoimmune PAP represented 89.9 % of cases and had a minimum incidence and prevalence of 0.49 and 6.2 per million, respectively. The male to female ratio was 2.1:1 and the median age at diagnosis was 51 years. A history of smoking occurred in 56% and dust exposure in 23%; instances of familial onset did not occur. Dyspnea was the most common presenting symptom occurring in 54.3%. Importantly, 31.8% of patients were asymptomatic and identified by health screening. Intercurrent illnesses including infections were infrequent. A disease severity score reflecting the presence of symptoms and degree of hypoxemia correlated well with DLCO and serum biomarkers, less-well with pulmonary function, and not with GM-CSF autoantibody levels or duration of disease. Conclusions: Autoimmune PAP had an incidence and prevalence higher than previously reported and was not strongly linked to smoking, occupational exposure or other illnesses. The disease severity score and biomarkers provide novel and potentially useful outcome measures in PAP. Key words: Epidemiology, serum biomarkers, disease severity score, GM-CSF, autoantibody
This article has been cited by other articles:
|
|
||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
