The value of Tc-99m (V) dimercaptosuccinic acid in detecting intra-abdominal infection: compared with gallium scan.
OBJECTIVE
Gallium-67 (Ga-67) and labeled leukocytes are useful in the detection of an unknown infectious source. However, the delay in the diagnosis of a Ga-67 citrate scan (gallium scan) and the complicated labeling technique of a leukocyte scan are major drawbacks to their clinical use. Recently, Tc-99m (V) dimercaptosuccinic acid (DMSA) has been found to be very useful in the detection of infection. Tc-99m (V) DMSA is inexpensive, easy to prepare, and provides a result within hours. In this study, we evaluated the potential of Tc-99m (V) DMSA scan (DMSA scan) in the detection of intra-abdominal infection.


METHODS
A total of 33 patients who suffered from an unknown cause of fever after colorectal surgery were enrolled in this study. All patients received both a gallium scan and a DMSA scan. DMSA scintigraphy was performed 3-4 h after an injection of 740 MBq (20 mCi) of Tc-99m DMSA. After completion of the DMSA image, 111 MBq (3 mCi) of Ga-67 citrate was injected intravenously. Gallium scintigraphy was performed after 24 h and later as needed.


RESULTS
Of the 33 patients, 17 (51.5%) were diagnosed with intra-abdominal abscesses. For DMSA scans, the sensitivity, specificity, and overall accuracy were 88.2%, 93.7%, and 90.9%, respectively. For gallium scans, the diagnostic sensitivity, specificity, and accuracy were 100%, 87.5%, and 93.9%, respectively. No statistical difference was found in the diagnostic accuracy between these two diagnostic modalities using Fisher's exact test.


CONCLUSIONS
DMSA scan is a useful alternative to gallium scan in the detection of intra-abdominal infection in patients with colorectal surgery because Tc-99m DMSA is inexpensive, easy to prepare, and most importantly the result can be obtained within hours.
Lin
Wan-Yu
WY
Department of Nuclear Medicine, Taichung Veterans General Hospital, 160 Taichung Harbor Road, Section 3, Taichung, Taiwan. wylin@vghtc.gov.tw
Hung
Guang-Uei
GU
Chao
Te-Hsin
TH
D000368:Aged; D002951:Citrates / Q000494:pharmacology; D003106:Colon / Q000601:surgery; D015179:Colorectal Neoplasms / Q000150:complications / Q000601:surgery; D005260:Female; D005334:Fever / Q000175:diagnosis; D005708:Gallium / Q000494:pharmacology; D005710:Gallium Radioisotopes / Q000494:pharmacology*; D006801:Humans; D007239:Infections / Q000175:diagnosis / Q000000981:diagnostic imaging*; D008297:Male; D008875:Middle Aged; D011877:Radionuclide Imaging; D019275:Radiopharmaceuticals / Q000494:pharmacology*; D012680:Sensitivity and Specificity; D013530:Surgical Wound Infection / Q000175:diagnosis; D019783:Technetium Tc 99m Dimercaptosuccinic Acid / Q000494:pharmacology*
D002951:Citrates; D005710:Gallium Radioisotopes; D019275:Radiopharmaceuticals; D019783:Technetium Tc 99m Dimercaptosuccinic Acid; D005708:Gallium; C103850:gallium citrate