Study objective: Pulmonary vascular leakiness of
67Ga-circulating transferrin in interstitial pneumonitis
(IP) was estimated by our previously described method, and its ability
to evaluate disease activity was compared with conventional
Design: Using 30-min
dynamic scanning data after IV injection of 67Ga citrate,
the exponential equilibration coefficient of 67Ga between
the intravascular and pulmonary interstitial compartments was
calculated and defined as the leak index (LI). Pulmonary
67Ga uptake was assessed by gallium index, determined by
conventional static images taken 48 h after 67Ga
Participants: The study population consisted
of 17 control patients and 20 patients with IP.
Results: The mean LI in patients with IP was significantly
higher than in the control group (p < 0.0001), whereas no
significant increase in gallium index was noted between the IP group
and the control group. No significant correlation was found between
gallium index and LI among all study participants. Mean LI in patients
with active IP was significantly higher than in patients with stable IP
(p = 0.0024).
Conclusions: An increase in pulmonary
vascular leakiness was found in patients with IP. LI may be useful to
assess the disease activity.