Diagnosing infection in febrile granulocytopenic patients with indium-111-labeled human immunoglobulin G.
OBJECTIVE
Delineation of focal infection is a major problem in the management of febrile granulocytopenic patients. The utility of indium-111-labeled human nonspecific immunoglobulin G (In-111-IgG), a newly developed radiopharmaceutical for imaging focal inflammation, was reported in patients with adequate WBC counts. In the present study, we investigated whether In-111-IgG scintigraphy could be used to locate infection in granulocytopenic patients.


METHODS
Granulocytopenic rats with focal infection were imaged after In-111-IgG injection. Thereafter, In-111-IgG scintigraphy was performed in 20 granulocytopenic patients. Images were obtained 4, 24, and 48 hours after injection of 75 mBq In-111-IgG. Scintigraphic findings were compared with clinical, roentgenologic, and ultrasonographic methods and culture results.


RESULTS
In the animal model high In-111-IgG accumulation was observed in the infectious focus. In the patients, 13 proven pulmonary, abdominal, joint, and soft tissue infections of both bacterial and fungal origin were detected adequately. In-111-IgG uptake not due to verified inflammation was observed in the large bowel of two patients. A thoracic wall infiltrate showing only mild inflammatory activity was not detected. Small toxoplasmosis lesions in heart, liver, and kidneys were obscured by physiologic In-111-IgG activity in these organs.


CONCLUSIONS
In-111-IgG scintigraphy is a useful technique to delineate focal infection in patients with granulocytopenia. Accumulation of the radiopharmaceutical does not appear to be granulocyte-mediated. In-111-IgG is a safe and convenient radiopharmaceutical that probably contributes to the early diagnosis of focal infection in granulocytopenic patients.
Oyen
W J
WJ
Department of Nuclear Medicine, University Hospital Nijmegen, The Netherlands.
Claessens
R A
RA
Raemaekers
J M
JM
de Pauw
B E
BE
van der Meer
J W
JW
Corstens
F H
FH
D000293:Adolescent; D000328:Adult; D000380:Agranulocytosis / Q000150:complications*; D000818:Animals; D005260:Female; D005334:Fever / Q000209:etiology*; D006801:Humans; D007074:Immunoglobulin G; D007205:Indium Radioisotopes; D007239:Infections / Q000150:complications / Q000000981:diagnostic imaging* / Q000209:etiology; D008297:Male; D008875:Middle Aged; D011237:Predictive Value of Tests; D011877:Radionuclide Imaging; D051381:Rats
D007074:Immunoglobulin G; D007205:Indium Radioisotopes