Clinical value of gallium-67 scintigraphy in assessment of disease activity in Wegener's granulomatosis.
BACKGROUND
Diagnosis of active pulmonary and paranasal involvement in patients with Wegener's granulomatosis (WG) can be difficult. The diagnostic value of gallium-67 scintigraphy in WG is unclear.


OBJECTIVE
To evaluate the added diagnostic value of gallium-67 scintigraphy in patients with WG with suspected granulomatous inflammation in the paranasal and chest regions.


METHODS
Retrospectively, the diagnostic contribution of chest and head planar gallium scans in 40 episodes of suspected vasculitis disease activity in 28 patients with WG was evaluated. Scans were grouped into normal or increased uptake for each region. Histological proof or response to treatment was the "gold standard" for the presence of WG activity.


RESULTS
WG activity was confirmed in 8 (20%) episodes, with pulmonary locations in three, paranasal in four, and both in one (n=7 patients); all these gallium scans showed increased gallium uptake (sensitivity 100%). Gallium scans were negative for the pulmonary area in 23/36 scans (specificity 64%), and negative for paranasal activity in 13/16 scans (specificity 81%) in episodes without WG activity. Positive predictive value of WG activity for lungs and paranasal region was 24% and 63%, respectively, negative predictive value was 100% for both regions. False positive findings were caused by bacterial or viral infections.


CONCLUSIONS
Gallium scans are clinically helpful as a negative scan virtually excludes active WG. Gallium scintigraphy of chest and nasal region has a high sensitivity for the detection of disease activity in WG. However, because of positive scans in cases of bacterial or viral infections, specificity was lower.
Slart
R H J A
RH
Department of Nuclear Medicine, Groningen University Medical Centre, The Netherlands. r.slart@nucl.azg.nl
Jager
P L
PL
Poot
L
L
Piers
D A
DA
Tervaert
J-W Cohen
JW
Stegeman
C A
CA
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D002951:Citrates; D003937:Diagnosis, Differential; D005260:Female; D005708:Gallium; D005710:Gallium Radioisotopes; D014890:Granulomatosis with Polyangiitis / Q000000981:diagnostic imaging*; D006801:Humans; D008099:Liver / Q000000981:diagnostic imaging*; D008168:Lung / Q000000981:diagnostic imaging*; D008297:Male; D008875:Middle Aged; D010256:Paranasal Sinuses / Q000000981:diagnostic imaging*; D011237:Predictive Value of Tests; D011877:Radionuclide Imaging; D019275:Radiopharmaceuticals; D012189:Retrospective Studies
D002951:Citrates; D005710:Gallium Radioisotopes; D019275:Radiopharmaceuticals; D005708:Gallium; C103850:gallium citrate