Accuracy of individual in the monitoring of long term change in pulmonary sarcoidosis as judge by serial HRCT data

In pulmonary sarcoidosis, the optimal means of quantifying change is uncertain. The comparative utility of simple lung function trends and chest radiography remains unclear. We aimed to explore and contrast the disease monitoring strategies of serial pulmonary function tests and chest radiography, compared against morphologic change on high-resolution computed tomography (HRCT).73 patients with sarcoidosis were identified who had two HRCT scans with concurrent chest radiography and PFTs. Chest radiography's and HRCT's were assessed by two radiologists for change in disease extent. Concordance between the scoring systems, as well as agreement between PFT trends (% change from baseline in FEV1, FVC and DLCO), chest radiography and chest HRCT change, were examined using the weighted kappa coefficient of variation (Kw).There was fair agreement between change in extent of disease on chest radiograph and significant PFT trends (Kw = 0.35, p<0.001) and moderate agreement between change in extent of disease on serial HRCT scan and significant PFT trends (Kw = 0.64, p<0.0001). The integration of DLCO trends did not improve concordance between change on HRCT and PFT change. Change in KCO (i.e. DLCO/VA) displayed no overall linkage with change in chest radiographic extent (Kw = 0.07, p = 0.27), and only poor agreement between with change in HRCT extent (Kw = 0.17, p= 0.07).Significant PFT trends correlate better with morphologic change as defined by serial HRCT scan than radiographic extent of disease. Isolated change in KCO is more frequently discordant with change in disease extent on chest radiograph and HRCT scan and may suggest a pulmonary vascular component.