ABSTRACT
Sarcoidosis, a multisystemic granulomatous disease of uncertain etiology,
involves the lung or intrathoracic lymph node in more than 90% of patients (1-4). Although the clinical spectrum of sarcoidosis is diverse, pulmonary
manifestations predominate (1,5). The clinical course is highly variable. Various studies indicate that 30% to 50% of patients are asymptomatic at the time of diagnosis (5). Spontaneous remissions occur in nearly two thirds
of patients, but the course is chronic in 10% to 30% (5). Chronic sarcoidosis involving the lungs or extrapulmonary organs can be debilitating; fatalities
occur in 1% to 4% of patients (1,2). Treatment of sarcoidosis is controversial (4), with corticosteroids remaining the mainstay of therapy for patients with
symptomatic or progressive disease. Short-term responses are often dra-
matic, but relapses are common with cessation or tapering of the drug. Long-term efficacy of any form of therapy has not been proven, and lung
transplantation is an option for a small group of patients with end-stage sar-
coidosis (6). Given the importance and marked heterogeneity of disease
course in sarcoidosis, it is not surprising that pulmonary function testing
has become a mainstay for the staging and management of sarcoidosis.
