technetium-tc-99m-exametazime and Endocarditis--Bacterial

This prospective, single-center study sought to assess to what extent there is interference between the hybrid technique of single-photon emission tomography-computed tomography with technetium99m-hexamethylpropyleneamine oxime-labeled leukocytes (99mTc-HMPAO-SPECT/CT) and antimicrobial therapy in patients with infective endocarditis (IE).. During the years 2015-2019, we enrolled 205 consecutive adults with suspected IE, all underwent 99mTc-HMPAO-SPECT/CT. The study population was divided into those who had received antimicrobial therapy up to 30 days prior to 99mTc-HMPAO-SPECT/CT (group 1, n = 96) and those who had not (group 2, n = 109). Patients were prospectively observed for 12 ± 10 months. Group 1 presented higher positive predictive values (91.89% vs. 60.00%, = 0.001), and decreased negative predictive values (77.97% vs. 90.54%, P = 0.04). Patients treated with antimicrobial therapy displayed false-negative 99mTc-HMPAO-SPECT/CT results more often [odds ratio (OR), 4.63; 95% confidence interval (CI), 1.41-15.23, P = .01], particularly when intravenous (OR 5.37; 95% CI 1.73-16.62, P = .004), definite (OR 9.43; 95% CI 2.65-33.51, P = .001), and combination antibiotic regimens (OR 8.1; 95% CI 2.57-25.64, P = .001) had been administered.. Prior antibiotic therapy affects 99mTc-HMPAO-SPECT/CT diagnostic properties. Patients treated with antimicrobial therapy display false-negative 99mTc-HMPAO-SPECT/CT results more often, especially if intravenous, definite, or combination regimens are administered.

Topics: Adult; Anti-Infective Agents; Endocarditis; Endocarditis, Bacterial; Humans; Leukocytes; Prospective Studies; Technetium Tc 99m Exametazime; Tomography, Emission-Computed, Single-Photon

The radionuclide investigation was performed 1-3 and 24 hours after injection of a radiopharm preparation and included the single photon emission computed tomography of the heart and scintigraphy of the whole body. Inflammation foci were found on the scans as hyperfixation foci of autoleukocytes labeled with 99mTc-HMPAO (hexamethylpropilene aminooxime). Four patients had abscesses with 0.8-1.5 cm diameter in projection of the aortal and mitral valves of the heart, and in 10 patients there were foci of inflammation and suppuration of extracardiac localization (in the area of the operation wound, anterior mediastinum, frontal sinuses, transverse colon, parietal pleura). The data obtained convincingly speak of high sensitivity and specificity of radionuclide diagnostic methods with the help of labeled elements of the whole blood in recognizing latent inflammatory and suppurative processes in cardiosurgical patients at the pre- and postoperative periods.

Topics: Adolescent; Adult; Aortic Valve; Endocarditis, Bacterial; Female; Focal Infection; Heart Valve Diseases; Heart Valve Prosthesis Implantation; Humans; Leukocytes; Male; Middle Aged; Mitral Valve; Radionuclide Imaging; Radiopharmaceuticals; Rheumatic Heart Disease; Surgical Wound Infection; Technetium Tc 99m Exametazime

A 56-year-old man with Staphylococcal aureus septicemia and clinically suspected infective endocarditis was imaged using Tc-99m HMPAO leukocytes. Although abnormal uptake was seen at 3 hours after injection, 24-hour images demonstrated marked concentration of radiolabeled leukocytes in a myocardial abscess and large posterior parietal infarct. In addition, multiple splenic infarcts were shown. The Tc-99m labeled leukocyte scan proved to be an excellent whole body screening procedure for diagnosing sites of infection and infarction in this patient.

Topics: Bacteremia; Cerebral Infarction; Endocarditis, Bacterial; Humans; Leukocytes; Male; Middle Aged; Organotechnetium Compounds; Oximes; Radionuclide Imaging; Splenic Infarction; Staphylococcal Infections; Technetium Tc 99m Exametazime; Time Factors

Thirty patients with clinical signs of infective endocarditis and pathologic echocardiographic findings indicating vegetations underwent scanning with In-111 or Tc-99m hexamethylpropylene amineoxime (HMPAO) labeled granulocytes. Blood cultures were positive in 60% of the patients. The other cases were negative as a result of antibiotic pretreatment. The results of scintigraphy were correlated with the subsequent clinical course, and in 20 cases with data obtained by histologic examination of the valves. With regard to the degree of the inflammatory process, the nuclear medical procedure provided the following results: true-positive in 6 cases, false-positive in 1 case, true-negative in 19 cases, and false-negative in 3 cases. In this study, positive granulocyte scans correlate with high activity of the inflammatory process and predict a poor prognosis for the patients concerned.

Topics: Echocardiography; Endocarditis, Bacterial; Female; Granulocytes; Humans; Indium Radioisotopes; Male; Organometallic Compounds; Organotechnetium Compounds; Oximes; Oxyquinoline; Predictive Value of Tests; Prognosis; Radionuclide Imaging; Sensitivity and Specificity; Technetium Tc 99m Exametazime

Thirty patients with clinically suspected infective endocarditis were scanned with Indium-111- or Tc-99m-HM-PAO-labeled granulocytes. The scans were correlated with the clinical course, and in 20 cases with the results from histologic examination of the valves. In six cases the scintigraphic examination gave correct positive results, in three cases false negative, in one case a false positive, and in 20 cases correct negative results. If we limit the analysis to only the histologically proven cases, our data suggest a specificity of the method of 86% and a sensitivity of about 67%.

Topics: Abscess; Echocardiography; Endocarditis, Bacterial; Granulocytes; Heart Valve Prosthesis; Heart Valves; Humans; Image Enhancement; Indium Radioisotopes; Leukocyte Count; Organotechnetium Compounds; Oximes; Radionuclide Imaging; Sepsis; Technetium Tc 99m Exametazime