Pulmonary 99mTc-DTPA aerosol clearance and survival in usual interstitial pneumonia (UIP). Issue 12 (1st December 2001)

• Record Type: Journal Article
• Authors: Mogulkoc, N; Brutsche, M H; Bishop, P W; Murby, B; Greaves, M S; Horrocks, A W; Wilson, M; McCullough, C; Prescott, M; Egan, J J
• Is Part Of: Thorax. Volume 56:Issue 12(2001)
• Page Start: 916
• Page End: 923
• Publication Date: 2001-12-01
• Subjects: idiopathic pulmonary fibrosis -- cryptogenic fibrosing alveolitis -- 99mTc-DTPA clearance -- survival; Chest -- Diseases -- Periodicals; Thorax; Chest -- Diseases; Periodicals; Periodicals; 617.54
• DOI: 10.1136/thorax.56.12.916
• Languages: English
• ISSNs: 0040-6376

Abstract

Abstract : BACKGROUND: Clearance of inhaled technetium 99m-labelled diethylenetriamine penta-acetic acid ( 99m Tc-DTPA) from the lungs is a potential indicator of disease progression in patients with idiopathic pulmonary fibrosis (IPF). METHODS: We prospectively analysed the usefulness of this technique for predicting survival in 106 non-smoking patients with usual interstitial pneumonia (UIP) pattern IPF diagnosed by high resolution CT (HRCT) scanning or histological examination (M/F 65/41, mean (SD) age 61 (11) years). DTPA clearance was analysed according to both mono-exponential and bi-exponential models. Half times for the fast ( t 0.5 F ) and slow ( t 0.5 S ) components of clearance, the percentage contribution of the fast component ( f F ), and half time for mono-exponential approximation to the early part of the clearance curve ( t 0.5 ) were calculated. RESULTS: The patients had substantially faster t 0.5 (mean 23.9 (9.6) minutes) than normal values (>45 minutes). Thirty seven patients (35%) died during follow up (median 15 months). Univariate Cox regression analysis identified significant predictors of survival as age, forced expiratory volume in 1 second (FEV1 ), forced vital capacity (FVC), total lung capacity (TLC), % predicted TLC, carbon monoxide transfer factor (Tlco ), % predicted Tlco, arterial oxygen tension (Pao 2 ), oxygen saturation, t 0.5 F, and HRCT fibrosis score. Multiple stepwise Cox regression analysis identified t 0.5 F (p=0.03, hazard ratio 0.747, 95% CI 0.578 to 0.964), % predicted TLC (p=0.02, hazard ratio 0.976, 95% CI 0.956 to 0.995), % predicted Tlco (p=0.003, hazard ratio 0.960, 95% CI 0.935 to 0.986), and age (p=0.003, hazard ratio 1.062, 95% CI 1.021 to 1.104) as independent predictors of survival. CONCLUSION: These data suggest that 99m Tc-DTPA clearance t 0.5 F measurement may predict survival in patients with UIP pattern IPF.