Inflammatory activity is still present in the advanced stages of idiopathic pulmonary fibrosis.

OBJECTIVE: The role of active inflammation in idiopathic pulmonary fibrosis (IPF) is controversial. A gallium-67 citrate (Ga(67) scan) is a sensitive indicator of inflammatory activity. The aim of this study was to assess the Ga(67) uptake and other markers of inflammation at different stages of IPF and to investigate its prognostic role. METHODOLOGY: Twenty-two patients (aged 66 +/- 11 years, 18 males) with IPF were monitored for a period of 6-20 months (mean 13 months). At presentation (T0), high resolution CT (HRCT) scans showed reticular opacities and traction bronchiectasis with bi-basilar and peripheral distribution in all cases. At both T0 and follow-up (T1), we measured pulmonary function (PaO(2), FVC, DLco), overall radiographic extent of fibrosis (HRCT visual score), Ga(67) uptake, serum concentrations of lactate dehydrogenase (LDH) and C-reactive protein (CRP), and erythrocyte sedimentation rate (ESR). RESULTS: All parameters showed a significant deterioration during the T0-T1 interval, though the increase in Ga(67) uptake and serum markers was not significant. Patients with Ga(67) uptake indices graded as normal or mildly increased (group I), and graded as considerably or severely increased (group II) at presentation, were compared. There was no significant difference with respect to lung function or HRCT score between the two groups at T1. Ga(67) uptake, LDH, CRP and ESR at presentation did not correlate significantly with the interval change in pulmonary function and disease extent. CONCLUSIONS: Our findings indicate that inflammatory activity in the advanced stage of IPF is still relevant, although a Ga(67) scan is not predictive of the clinical course.

Does technetium-99m diethylenetriaminepentaacetate clearance predict the clinical course of idiopathic pulmonary fibrosis?

Clearance of inhaled technetium-99m diethylenetriaminepentaacetate (99mTc-DTPA) is a potential indicator of disease activity and progression in idiopathic pulmonary fibrosis (IPF). The objective of the present study was to evaluate the prognostic value of 99mTc-DTPA scans in IPF. A total of 22 patients (18 males), aged 33 to 80 years with IPF were followed for six to 20 months (mean 13 months). At diagnosis, high resolution computed tomography (HRCT) scans showed a honeycomb pattern with bibasilar reticular opacities in all cases. At T0 (diagnosis) and T1 (follow-up), each patient had pulmonary function tests (forced vital capacity, diffusing capacity of the lung for carbon monoxide and partial arterial O2 pressure), extension of fibrosis evaluated by HRCT visual score and 99mTc-DTPA lung clearance. Results at T0 and T1 were compared, taking into account the whole population and patients with relatively fast and slow 99mTc-DTPA wash-out. 99mTc-DTPA clearance did not show any significant correlation with functional tests or HRCT score. These findings indicate that clearance of inhaled 99mTc-DTPA is not of value in following the progress of IPF.