PURPOSE: The sarcoidosis Scadding chest x-ray staging system can miss subtle parenchymal involvement. Mild and severe parenchymal changes may be classified in the same stage and changes in parenchymal involvement may not change the classified stage. Radiographic manifestations often do not correlate with physiologic abnormalities. Our goal was to create a pulmonary scoring system combining imaging and physiological elements to assess degree of lung involvement in sarcoidosis.
METHODS: We performed a retrospective chart review for sarcoidosis patients who underwent CPET in 2008-2009. A priori, we defined our scoring system as follows: A score of 0 for Scadding stages 0, I, ;1 for Scadding stages II, III; and 2 for stage IV. For PFT data: a score of 0 for DLCO%> 80%; 1 for DLCO% 60-79%; 2 for DLCO%<59%.; 0 for FVC%> 80%; 1 for FVC% 60-79%; 2 for FVC%<59%; 0 for FEV1/FVC%> 70%; and 1 for FEV1/FVC%≥ 70%. Scores were added up for a final score ranging 0-7.
RESULTS: 92 patients were included: 52.2% male, 86.2% Caucasians, 9.6% African Americans, 65.2% never smokers, 37% on steroids and 20% on second line Immunosuppressants. Scadding stages : 0 (8.5%), I (4.3%), II (50%), III (19.1%) and IV (18.1%). On average PFT results [Mean (±SD)] were as follows: FVC%: 78.7%±16, DLCO%: 75.2%±15.7, FEV1/FVC%: 72.4%±13.2. Significant correlation was found between our pulmonary sarcoidosis score and VO2max% R2=0.23 (p<0.001), PaO2max R2=0.48 (p<0.0001), PaO2rest R2=0.28 (p<0.0001), Breathing Reserve R2=0.11 (p=0.001), A-a gradient rest R2=0.33 (p<0.0001), A-a gradient max R2=0.35 (p<0.0001), dead space ventilation at rest R2=0.26 (p<0.0001) and dead space ventilation at maximum exercise R2=0.07 (p=0.008).
CONCLUSION: Our new pulmonary sarcoidosis scoring system significantly correlated with CPET ventilatory and gas exchange measurements reflecting the burden of sarcoidosis on the lung and impairment in lung function.
CLINICAL IMPLICATIONS: The new pulmonary scoring system could be used to assess the overall pulmonary disease burden. Further validation on an extended cohort of sarcoidosis subjects and correlation with a HRCT score is underway.
DISCLOSURE: Nabeel Hamzeh, No Financial Disclosure Information; No Product/Research Disclosure Information