THE CLINICAL USE OF 99M-TC-LABELED WBC SCINTIGRAPHY IN CRITICALLY ILLSURGICAL AND TRAUMA PATIENTS WITH OCCULT SEPSIS

Objective: To evaluate the clinical use of radionuclide-labeled white blood cell scintigraphy in the detection of focal sepsis. Design: Pros pective clinical study. Setting: A medical/surgical 12-bed intensive c are unit (ICU) in a university hospital. Patients: 26 trauma and surgi cal patients affected by sepsis of unknown origin were studied. Measur ements and results: After the usual diagnostic approach, patients were submitted to a total body scan by using the patient's leukocytes labe led with technetium-99m (99m-Tc) HMPAO; three scintigraphy were perfor med within 20 h of tracer injection; the result of scan was completed with all clinical and instrumental data, including ultrasound (US) and computed tomography (CT), and the diagnostic efficacy was demonstrate d for each patient on discharge from the ICU. The scan was able to det ect 20 sites of infection; it was possible to rule out 11 suspected si tes; only in two cases was the result considered to be false positive or false negative; in two cases the result was considered to be uncert ain. These results show the high sensitivity (95%), specificity (91%) and accuracy (94%) of the method. Conclusions: In ICU patients with se psis, nuclear medicine can provide additional data, as the injection o f radionuclide-labeled white blood cells (WBCs) allows the imaging of sites of infection. Analysis of our results suggests that scintigraphy with 99m-Tc-labeled WBCs can be considered a useful tool in the detec tion of the source of infection.