technetium-tc-99m-exametazime and indium-oxine

Diagnosing diabetic foot infection is often difficult, despite several available diagnostic methods. Amongst these, several imaging modalities exist to evaluate the diabetic foot in case of a suspected osteomyelitis. Nuclear Medicine, in particular, offers a variety of radiopharmaceuticals and techniques. Nowadays the gold standard radionuclide procedure, when an osteomyelitis is suspected, is represented by the use of radiolabelled leukocytes with either. In this review, we describe the correct acquisition and interpretation of white blood cell scintigraphy and we provide an overview of the existing literature data of the use of this technique in the infected diabetic foot. If images are correctly acquired, displayed and interpreted, this modality reaches very high diagnostic accuracy (>95%) in detecting osteomyelitis and it allows the differential diagnosis with a soft tissue infection or inflammation. Single-photon emission computed tomography/computed tomography (SPECT/CT) in addition to planar images is mandatory to determine the extent and exact location of the infective process in both fore foot and midhint foot. With the addition of bone marrow scintigraphy using radiolabelled nanocolloids, radiolabelled white blood cell scintigraphy is also able to differentiate between Charcot neuroarthropathy and osteomyelitis, which is a challenge in the evaluation of diabetic foot. Radiolabelled anti-granulocyte monoclonal antibodies and their fragments can also be used instead of white blood cells although there is a limited experience on their usefulness in diabetic foot infection.

Topics: Diabetic Foot; Humans; Leukocytes; Organometallic Compounds; Oxyquinoline; Technetium Tc 99m Exametazime; Tomography, Emission-Computed, Single-Photon

With a current annual mortality rate of around 35% worldwide, infection remains a significant concern, and the diagnosis and localization of infectious foci is an important health issue. As an established infection-imaging modality, nuclear medicine plays a vital health-care role in the diagnosis and subsequent effective treatment of this condition. Despite the development of several newer radiopharmaceuticals, (67)Ga and leukocyte imaging procedures have maintained their established place for infection. Several techniques in nuclear medicine significantly aid infection diagnosis, including imaging with (111)In-oxine-, (99m)Tc-hexamethylpropyleneamine oxime-, and (99m)Tc-stannous fluoride colloid-labeled leukocytes and with (67)Ga-citrate. Each radiopharmaceutical has specific advantages and disadvantages that make it suitable to diagnose different infectious processes (e.g., soft-tissue sepsis, inflammatory bowel disease, osteomyelitis, occult fever, fever of unknown origin, and infections commonly found in immunocompromised patients). After finishing this article, the reader should be able to identify the properties of an ideal radiopharmaceutical for infection imaging, list a range of available infection-imaging radiopharmaceuticals, compare the relative results of a range of radiopharmaceuticals used internationally to detect infection in the body, understand several common infectious processes that can be diagnosed using nuclear medicine techniques, and select an appropriate radiopharmaceutical to image a range of infectious processes.

Topics: Citrates; Fever of Unknown Origin; Gallium; Humans; Infections; Irritable Bowel Syndrome; Leukocytes; Nuclear Medicine; Organometallic Compounds; Osteomyelitis; Oxyquinoline; Practice Patterns, Physicians'; Predictive Value of Tests; Radiopharmaceuticals; Reproducibility of Results; Sensitivity and Specificity; Sepsis; Technetium Compounds; Technetium Tc 99m Exametazime; Tin Fluorides; Tomography, Emission-Computed

Investigators have used various techniques and radionuclides such as 51Cr and 32P-diisofluorophosphate to label blood cells and to study cell survival. Early studies also used these radionuclides to label human leucocytes for cell survival by in-vitro counting. But external imaging could not be done with these agents. Starting with the use of the gamma-emitting radionuclide (111)In-oxine for in-vitro labelling of phagocytic leucocytes, external imaging became possible. This method was the basis of visualisation of cell distribution within the body. Because an abscess consists primarily of leucocytes, leucocytes labelled with (111)In localise within the abscess and are detectable by imaging. Nowadays other radiopharmaceuticals with other underlying uptake mechanisms are also used to detect inflammatory or infectious foci in patients. Nuclear medicine can be most useful in patients with fever of unknown origin, where a focus has to be defined, or in patients where a lesion is known by clinical symptoms or by a radiological imaging and the differentiation between infection and other pathologies has to be made.

Topics: Fever of Unknown Origin; Fluorine Radioisotopes; Gallium Radioisotopes; Humans; Indium Radioisotopes; Infections; Inflammation; Leukocytes; Nuclear Medicine; Organometallic Compounds; Oxyquinoline; Radioimmunodetection; Radiopharmaceuticals; Technetium Tc 99m Exametazime

Topics: Antibodies, Monoclonal; Blood Platelets; Cell Separation; Cellular Senescence; Granulocytes; Hematologic Diseases; Humans; Indium Radioisotopes; Isotope Labeling; Leukocytes; Liver; Organometallic Compounds; Oxyquinoline; Radionuclide Imaging; Spleen; Technetium Tc 99m Exametazime

Radiolabelled leucocytes migrate rapidly to sites of acute inflammation. The simplest technique for imaging intestinal inflammation involves radiolabelling patients' mixed while cells ex vivo with either 99mTc or 111In which are then reinjected. However, further purification of mixed white cells to granulocytes is needed for optimal results using 111In. Owing to the simpler labelling procedure, availability, image quality and dosimetry, 99mTc-HMPAO has gained favour for the investigation of acute inflammation including inflammatory bowel disease. Because of its longer half life. 111In is more suited to the imaging of chronic inflammation such as osteomyelitis. Attempts to radiolabel granulocytes in vivo using monoclonal anti-granulocyte antibodies have been largely unsuccessful to date, and this approach remains a challenge for the future.

Topics: Cell Separation; Granulocytes; Humans; Indium Radioisotopes; Inflammatory Bowel Diseases; Leukocytes; Monocytes; Organometallic Compounds; Organotechnetium Compounds; Oximes; Oxyquinoline; Radionuclide Imaging; Technetium Tc 99m Exametazime

In cancer vaccination trials, antigen-loaded dendritic cells (DCs) are usually injected intradermally and are expected to rapidly move to a regional lymph node where antigen presentation should occur. In this study we investigated the influence of indium-111 oxine (111In) and technetium-99m hexamethylpropylene amine oxime (99mTc-HMPAO) labelling on the motility and actin content of antigen-loaded DCs in parallel with in vivo migration in humans. Human autologous monocyte-derived DCs loaded with a tumour antigen were labelled with 111In (0.11, 0.37 or 0.74 MBq/10(7) DCs) or 99mTc-HMPAO (18.5 or 185 MBq/10(7) DCs). 111In labelling was much more stable than 99mTc-HMPAO labelling. Quantitative videomicroscopy showed that the mean distance of displacement of DCs increased in accordance with the 111In activity used for labelling. Monomeric (G) and filamentous (F) actin content of DCs evaluated by quantitative immunofluorescence demonstrated that the ratio of filamentous to globular actin content in labelled DCs increased significantly in accordance with the activity used for labelling with both tracers. Twelve patients enrolled in a phase I/II vaccination trial received injections of 10(7) antigen-loaded DCs labelled with either 0.74 MBq of 111In (group A, n=6/12) or 18.5 MBq of 99mTc-HMPAO (group B, n=6/12) in the proximal part of the legs, one intradermally on one side, one subcutaneously on the opposite side. In three of the six patients of each group, antigen-loaded DCs were incubated with monophosphoryl lipid A (MPL) just before the labelling, in order to initiate the maturation process (subgroup MPL+). Only one MPL+ patient of group A exhibited faint focal uptake in the inguinal region on the late images. Group B presented a more complex pattern of radioactivity distribution (early bladder activity without brain uptake) indicating that 99mTc-HMPAO is not a suitable radiopharmaceutical for labelling of loaded DCs. The activity cleared from DCs as a labelled molecule different from the lipophilic 99mTc-HMPAO. Only one of the six patients had nodular inguinal uptake on the intradermally injected side (DCs not incubated with MPL). In conclusion, the present study did not demonstrate migration of loaded labelled DCs from intradermal or subcutaneous sites of injection to regional lymph nodes. This provides an indication that a large proportion of antigen-loaded DCs, as used in current human trials for cancer therapy, may not reach regional lymph nodes.

Topics: Actins; Antigens; Cell Movement; Cell Survival; Cells, Cultured; Dendritic Cells; Humans; Isotope Labeling; Lymph Nodes; Organometallic Compounds; Oxyquinoline; Radionuclide Imaging; Radiopharmaceuticals; Technetium Tc 99m Exametazime

Leukocyte labelling in patients with sickle cell anaemia has been reported as difficult if not impossible due to the slow erythrocyte sedimentation rate (ESR) in these patients. This study investigated standard sedimentation methods in patients with sickle cell disease (n = 16) and compared the results obtained with those following changes in the amount and type of sedimenting agent used. Labelling with either 111In-oxine or 99Tcm-exametazime was attempted in only five patients. Replacement of the commonly used 6% Hetastarch (Hespan) with Dextran or Haemaccel did not improve leukocyte harvesting, even when the proportions used of these agents were increased. In most cases where standard procedures for leukocyte collection did not lead to harvesting of viable samples, it was possible to obtain adequate leukocyte labelling in the majority of sickle cell patients using a minor modification of standard techniques. In this group of patients a ratio of 8 ml of Hespan to 16 ml of blood should be used for cell separation. If this fails then donor cells, anti-granulocyte antibody labelling or HIG should be considered.

Topics: Anemia, Sickle Cell; Blood Sedimentation; Dextrans; Humans; Hydroxyethyl Starch Derivatives; Indium Radioisotopes; Isotope Labeling; Leukapheresis; Leukocytes; Organometallic Compounds; Organotechnetium Compounds; Oximes; Oxyquinoline; Polygeline; Technetium Tc 99m Exametazime

This retrospective study assessed the effect of the addition of SPECT/CT imaging on the diagnostic accuracy of labeled leukocyte scintigraphy.. Leukocyte scans of 134 patients performed between December 2005 and December 2009 were reviewed. All patients underwent whole-body planar and SPECT/CT imaging with either (111)In-oxine- or Tc-99m-hexamethylpropylene amine oxime (HMPAO)-labeled leukocytes. Leukocyte imaging identified a total of 221 lesions. Based on additional diagnostic tests and clinical follow-up, a final diagnosis was established in 115 patients.. A total of 113 focal lesions with an established final diagnosis were detected on imaging in bone (n = 43), soft-tissues (n = 34), vascular grafts (n = 19), and other surgical implants (n = 17), whereas 26 scans resulted negative. Overall, leukocyte scanning including SPECT/CT yielded sensitivity, specificity, positive and negative predictive values of 87.5%, 85.3%, 83.6%, and 88.9%, respectively. As compared to planar imaging and SPECT, SPECT/CT imaging significantly increased the number of correctly identified lesion locations and improved overall reader confidence in 77 (68%) and 71 (63%) of 113 focal lesions, respectively (P < 0.001). Significant differences in scan accuracy were neither observed between In-oxine- or Tc-99m-hexamethylpropylene amine oxime-labeled leukocyte studies, nor between scans obtained with or without antibiotic treatment.. Hybrid SPECT/CT leukocyte imaging has incremental value over planar imaging with SPECT because of improved diagnostic accuracy of lesion identification and reader confidence.

Topics: Adolescent; Adult; Aged; Aged, 80 and over; Anti-Infective Agents; Female; Humans; Leukocytes; Male; Middle Aged; Organometallic Compounds; Oxyquinoline; Staining and Labeling; Technetium Tc 99m Exametazime; Tomography, Emission-Computed, Single-Photon; Tomography, X-Ray Computed

Topics: Adult; Child; Humans; Inflammatory Bowel Diseases; Leukocytes; Organometallic Compounds; Oxyquinoline; Predictive Value of Tests; Radionuclide Imaging; Radiopharmaceuticals; Technetium Tc 99m Exametazime

Topics: Adult; Child; Humans; Inflammatory Bowel Diseases; Leukocytes; Organometallic Compounds; Oxyquinoline; Predictive Value of Tests; Radionuclide Imaging; Radiopharmaceuticals; Technetium Tc 99m Exametazime

Topics: Blood Platelets; Cell Survival; Humans; Organometallic Compounds; Oxyquinoline; Radionuclide Imaging; Radiopharmaceuticals; Technetium Tc 99m Exametazime

One approach in the treatment of ovarian cancer patients involves the infusion of autologous T lymphocytes coupled with a bispecific monoclonal antibody MOv18/anti-CD3 (biMAb OC/TR), which recognizes a 38-kDa glycoprotein expressed on ovarian carcinomas and the CD3 T cell receptor. However, little is known about the in vivo biodistribution of injected activated lymphocytes, information that could be obtained by scintigraphic imaging of radiolabelled T cells in order to visualize the migratory pattern. We compared the efficiency, stability and toxicity of technetium-99m hexamethylpropylene amine oxime (HMPAO), indium-111 oxine and fluorine-18 2-fluoro-2-deoxy-d-glucose (FDG) in radiolabelling activated lymphocytes targeted with biMAb OC/TR. The mean labelling efficiencies of 111In-oxine and 18F-FDG using 2.5x10(8) lymphocytes (68% and 64%, respectively) were more than twice that of 99mTc-HMPAO (31%). Retention of the radionuclide in the cell was highest in the case of 111In-oxine labelling (less than 25% of the initial cell-bound activity released after 240 min, as compared with 44% of the 99mTc label in the same period and 45% of 18F radionuclide released after 150 min). None of the three radiolabelling reagents induced any significant alteration in cell viability or immunophenotype. However, both 111In-oxine and 18F-FDG induced a loss of cytotoxic activity of lymphocytes against the ovarian carcinoma cell line IGROV1, and all three radiolabelling reagents caused a significant reduction in the proliferative ability of labelled lymphocytes compared to controls, with cell death occurring after 8-9 days. Radiolabelling with the more stable 111In-oxine reagent using a higher number of lymphocytes (1.4x10(9)) but the same total activity (around 55.5 MBq) resulted in improved labelled T cell viability and proliferative ability, although the mean labelling efficiency decreased (35.8%). Together the data suggest that 111In-oxine at low activity per cell is the most appropriate reagent for radiolabelling activated retargeted T lymphocytes useful for in vivo biodistribution studies.

Topics: Cell Death; Cell Survival; Cells, Cultured; Deoxyglucose; Female; Fluorine Radioisotopes; Fluorodeoxyglucose F18; Humans; Indium Radioisotopes; Isotope Labeling; Lymphocyte Activation; Organometallic Compounds; Organotechnetium Compounds; Ovarian Neoplasms; Oximes; Oxyquinoline; T-Lymphocytes; Technetium Tc 99m Exametazime; Tumor Cells, Cultured

Clinical and laboratory data or imaging results cannot provide a positive diagnosis of septic complications of pancreatic and peripancreatic necrosis in patients with acute pancreatitis. Confirmation can be obtained only after percutaneous computed tomography (CT)-guided aspiration of the necrotic tissues or fluid collection; although the important role of 99Tc(m)-HMPAO-labeled granulocyte scintigraphy has been recently emphasized. The aim of this study was to determine the sensitivity and specificity of 99m-technetium-hexamethylpropyleneamine oxime (99Tc(m)-HMPAO)- or 111In-oxine-labeled granulocyte scintigraphy for the diagnosis of infection in pancreatic or peripancreatic necrosis to define the ideal label for diagnosis. Thirty-six scintigraphic examinations were performed in 34 consecutive patients (mean age, 58 +/- 2 years) 20 +/- 2 days after the onset of acute pancreatitis (Balthazar classes A-C, n = 7; classes D and E, n = 29). The scintigraphic study included scintigraphic tomography and static acquisition 1 and 3 h, respectively, after reinjection of the autologous 99Tc(m)-labeled granulocytes and static images 3-4 and 24 h after the simultaneous reinjection of 111In-oxine-labeled autologous granulocytes. The diagnosis of infected pancreatic or peripancreatic necrosis was confirmed with percutaneous CT-guided aspiration (14 positive aspirates among 20 performed) and sterile necrosis after negative aspiration (6 negative aspirates) or after a 6 +/- 1-month follow-up free of clinical or biological signs of ongoing sepsis. The sensitivity and specificity were 86 and 73%, respectively, for scintigraphic tomography, 100 and 55% for 3-h 111In images, 93 and 68% for 3-4-h 111In images, and 100 and 64% for 24-h 111In images. The fall in splenic activity between the 3-4 and the 24-h 111In images was 26 +/- 3% in patients with septic pancreatic and peripancreatic necrosis (n = 14) and 16 +/- 3% in those with sterile necrosis (n = 22) (p < 0.01). Labeled granulocyte scintigraphy was thus shown to be an effective tool for the diagnosis of infection in pancreatic and/or peripancreatic necrosis due to acute pancreatitis, especially when the scintiscans are performed early after injection of 99Tc(m) or when the fall in splenic activity over the 24 h following reinjection of 111In is measured in particularly difficult cases. These promising preliminary results should be confirmed by a prospective study.

Topics: Acute Disease; Aged; Female; Granulocytes; Humans; Indium Radioisotopes; Isotope Labeling; Male; Middle Aged; Necrosis; Organometallic Compounds; Organotechnetium Compounds; Oximes; Oxyquinoline; Pancreatitis; Radionuclide Imaging; Sensitivity and Specificity; Sepsis; Technetium Tc 99m Exametazime

The diagnostic value of imaging infection with labelled granulocytes depends on the functional integrity of the reinfused cells. The aim of this study was to compare the functional integrity of granulocytes labelled with indium-111-oxine and technetium-99m-hexamethylpropyleneamineoxime (HMPAO), respectively, in comparison to unlabelled control granulocytes. Granulocytes were purified from healthy subjects and labelled with either 111In-oxine or 99mTc-HMPAO. Chemotaxis and superoxide production induced by formyl-peptide and phorbol-myristate-acetate were measured. Granulocytes labelled with 111In-oxine had significantly (p < 0.001) decreased chemotaxis. Superoxide production of granulocytes stimulated with phorbol-myristate-acetate showed no significant difference between control cells and those labelled using either technique. In contrast, formyl-peptide-stimulated superoxide production was increased in granulocytes labelled with 111In-oxine (p < 0.01) and in cells labelled with 99mTc-HMPAO (p < 0.03), indicating a priming compared to unlabelled cells. In conclusion, 99mTc-HMPAO-labelled granulocytes show biological properties superior to 111In-oxine-labelled cells, and should therefore be favoured for use in leucocyte labelling and infectious disease imaging.

Topics: Chemotaxis, Leukocyte; Granulocytes; N-Formylmethionine Leucyl-Phenylalanine; Organometallic Compounds; Organotechnetium Compounds; Oximes; Oxyquinoline; Superoxides; Technetium Tc 99m Exametazime; Tetradecanoylphorbol Acetate

To investigate the trafficking of circulating blood neutrophils and synovial fluid neutrophils in rheumatoid arthritis (RA) patients and the influence of a 1,000-mg intravenous pulse of methylprednisolone succinate (MP).. Neutrophils were isolated from the circulation and from the knee synovial compartments of subjects with RA. Circulating neutrophils were labeled with technetium-99 hexametazime (99mTc-HMPAO) and reinjected intravenously. Synovial fluid neutrophils were labeled from indium-111 oxine and reinjected into the knee from which they were isolated. Gamma camera images were obtained at intervals up to 24 hours post MP. Each patient had a baseline study (no MP) and a study in which MP was administered either 4 hours before (2 patients), 10 minutes before (1 patient), or 30 minutes to 1.5 hours after (6 patients) injection of the radiolabeled neutrophils. Subsequent analysis allowed quantitation of the neutrophil uptake into and clearance from the knee as a function of time.. Nine patients who had not received glucocorticoids in the previous 3 months were studied. MP significantly decreased neutrophil ingress in 13 of the 16 knees studied (almost total inhibition in 5 knees), and this occurred within 1.5 hours of MP administration in all except 1 knee. At 24 hours after MP administration, there was a significant increase in visual analog scale (VAS) scores for well-being and significant decreases in scores on the modified Health Assessment Questionnaire (P<0.05), tender joints (P<0.005), VAS for pain (p<0.005), and generalized stiffness (P<0.005), as well as a decrease in the C-reactive protein level (P<0.05). MP had no effect on neutrophil egress (2 patients). Two additional patients who were receiving oral glucocorticoids were studied. One of them was clinically unresponsive to oral prednisolone, and MP had no effect on neutrophil ingress. The other patient showed no neutrophil ingress during the baseline study. This was confirmed by the presence of a noninflammatory synovial fluid at arthrocentesis.. Neutrophil ingress into and egress from inflamed joints can be accurately monitored using radiolabeled neutrophils and quantitative gamma camera imaging. MP rapidly and substantially decreases neutrophil ingress into inflamed joints. In contrast, MP has no effect on neutrophil egress from the joint.

Topics: Aged; Arthritis, Rheumatoid; Cell Movement; Female; Humans; Joints; Male; Methylprednisolone; Middle Aged; Neutrophils; Organometallic Compounds; Organotechnetium Compounds; Oximes; Oxyquinoline; Radionuclide Imaging; Technetium Tc 99m Exametazime

Indium-111-oxinate-labeled granulocytes have been used in vivo for several years for the detection of abscesses. Technetium-99-m-hexamethylpropyleneamine oxime (99mTc-HMPAO) labeling has more recently been described.. The influence of radiolabeling by both radiotracers on adhesion glycoprotein CD11b quantification was studied in quiescent and formyl-methionylleucylphenylalanine (fMLP)-activated neutrophils (PMN). Adhesion was assessed on human umbilical endothelial cells (HUVEC) as well as the repercussion of the granulocyte labeling on HUVEC viability (neutral red) and metabolic activity (MTT). Chemotaxis of PMN was evaluated by measuring migration under agarose with fMLP as chemoattractant. We also measured phagocytosis and the production of hydrogen peroxide induced by staphylococcus aureus.. Whereas whole functional integrity is maintained after labeling, most of the functions (CD11b expression, adhesion, HUVEC metabolic activity) are up-regulated while chemotaxis is decreased in the presence of both radiotracers. Indium-111-oxinate induces larger alterations than 99mTc-HMPAO.. These data were obtained in normal volunteers. In patients, alterations due to the in vitro labeling procedure, in addition to potential functional alterations caused by the underlying pathology, should be taken into account during image interpretation.

Topics: Cells, Cultured; Chemotaxis, Leukocyte; Endothelium, Vascular; Female; Humans; Hydrogen Peroxide; Indium Radioisotopes; Isotope Labeling; Lymphocyte Activation; Macrophage-1 Antigen; Male; Neutrophils; Organometallic Compounds; Organotechnetium Compounds; Oximes; Oxyquinoline; Phagocytosis; Respiratory Burst; Technetium Tc 99m Exametazime; Up-Regulation

This study assesses the causes of colonic localization of labeled white blood cells (WBCs) in critically ill patients who had undergone leukocyte scintigraphy for suspected infection. Forty-two patients showed abdominal or pelvic WBC localization; 20 of these had a pattern of colonic localization, and some also showed a pattern of small bowel activity. Eight of the 20 patients had documented gastrointestinal bleeding. White blood cell scintigraphy in these eight patients showed a pattern of multifocal and/or regional bowel activity that changed in intensity and location from early (3-5-hour) to delayed (18-28-hour) images. In contrast, 5 of the 6 patients with documented pseudomembranous colitis (PMC) showed intense WBC localization involving most of the colon. In 3 of these 5 patients, early and delayed images were acquired and showed a relatively constant pattern of WBC localization. The sixth PMC patient had been treated with vancomycin before leukocyte scintigraphy and showed minimal distal small bowel activity on early images and only mild regional colonic activity on delayed images. As in the patients with gastrointestinal bleeding, the remaining six patients showed either focal or regional activity of variable intensity that changed over time. In critically ill patients, gastrointestinal bleeding and PMC accounted for 14 of the 20 patients in which labeled leukocyte scintigraphy exhibited colonic activity. A pattern of diffuse, intense colonic radiotracer activity which persists from early to delayed imaging strongly suggests the presence of PMC in this patient population.(ABSTRACT TRUNCATED AT 250 WORDS)

Topics: Adolescent; Adult; Aged; Aged, 80 and over; Child; Clostridioides difficile; Colon; Enterocolitis, Pseudomembranous; Female; Gastrointestinal Hemorrhage; Humans; Indium Radioisotopes; Leukocytes; Male; Middle Aged; Organometallic Compounds; Organotechnetium Compounds; Oximes; Oxyquinoline; Radionuclide Imaging; Retrospective Studies; Sensitivity and Specificity; 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

Forty-seven patients, 29 with chronic inflammatory bowel disease (IBD) and 18 with presumed irritable bowel syndrome, including one with uncomplicated diverticular disease, were studied with simultaneous technetium-99m hexamethylpropylene amine oxime and indium-111 oxine labelled leucocyte scans performed at 1, 3 and 24 h. Twenty-seven patients with IBD had active disease as judged by clinical and laboratory criteria and all of these had positive scans with both agents. No false positive studies were obtained. The 1-h 99mTc-HMPAO WBC scans showed the same distribution to disease as the 3-h 111-In WBC scans, with no difference in intensity (P < 0.92); they showed more extensive disease (P < 0.02) and more intense uptake (P < 0.001) than did the 1-h 111-In scans. The 3-h 99mTc-HMPAO WBC scans showed more extensive disease (P < 0.002), with greater intensity (P < 0.0005), than did the 3-h 111In WBC scans. Physiological bowel activity on 3-h 99mTc-HMPAO WBC scans was present in 12 patients but was faint and did not interfere with assessment of disease extent and activity. It is concluded that in terms of isotope availability, radiation dosimetry and image quality, 99mTc-HMPAO is the agent of choice in detecting active IBD, with localization of disease possible at 1-h after re-injection and optimal resolution and definition of disease extent at 3 h. A negative scan reliably excludes active disease.

Topics: Adult; Colonic Diseases, Functional; Female; Humans; Indium Radioisotopes; Inflammatory Bowel Diseases; Intestines; Leukocytes; Male; Organometallic Compounds; Organotechnetium Compounds; Oximes; Oxyquinoline; Radionuclide Imaging; Technetium Tc 99m Exametazime; Time Factors

We report the results of imaging with labelled white cells in 52 patients before the revision of 54 cemented joint prostheses at which the diagnosis of infection was made from biopsies. Twenty-five hips were imaged with 111In-oxine-labelled cells; 20 hips and 11 knees were imaged with 99mTc-hexamethylpropylene-amineoxime-labelled cells. Of these, 13 hips and five knees proved to be infected. The scans taken together had an accuracy of 82%, a sensitivity of 44% and a specificity of 100%. Indium scans gave 37% sensitivity, 99mTc labelling 50% sensitivity. Infected arthroplasties with positive scans had presented significantly earlier than those with negative scans, the time after the original insertion being 1.1 years for the true-positive scans and 6.1 years for the false-negative scans. The value of labelled white-cell scans in the detection of infection in failed joint replacements is dependent on the activity of the infection. There is reduced sensitivity to the more insidious infections which affect arthroplasties and aspiration under controlled conditions remains an important investigation.

Topics: Biopsy, Needle; Diagnosis, Differential; Evaluation Studies as Topic; Hip Prosthesis; Humans; Indium Radioisotopes; Knee Prosthesis; Leukocytes; Organometallic Compounds; Organotechnetium Compounds; Oximes; Oxyquinoline; Prosthesis-Related Infections; Radionuclide Imaging; Sensitivity and Specificity; Technetium Tc 99m Exametazime; Time Factors

Scintigraphy with Tc-99m labeled antigranulocyte antibodies (BW 250/183 MoABs) was performed in 32 patients with suspected appendicitis. Abdominal imaging (planar/SPECT) was performed 2 hours after injection of the tracer. All patients also had surgery and a histologic examination of the resected tissue. Of the patients, 17 suffered from "acute appendicitis" and 12 had right positive scans (sensitivity = 70.6%). In 15 patients, acute appendicitis could have been ruled out, and in 11 of these cases the scan was true negative (specificity = 73.3%). The overall accuracy was 71.8% (23/32 cases). The use of Tc-99m antigranulocyte MoABs may overcome the problems associated with the Tc-99m HMPAO granulocyte and In-111 oxine approaches, which include nonspecific intestinal activity or the lack of timeliness. The use of Tc-99m labeled antigranulocyte antibodies is suitable as an emergency procedure and may play a role in the management of patients with suspected appendicitis.

Topics: Adolescent; Adult; Aged; Aged, 80 and over; Appendicitis; Child; Female; Granulocytes; Humans; Indium Radioisotopes; Leukocytes; Male; Middle Aged; Organometallic Compounds; Organotechnetium Compounds; Oximes; Oxyquinoline; Radioimmunodetection; Sensitivity and Specificity; Technetium; Technetium Tc 99m Exametazime; Tomography, Emission-Computed, Single-Photon

Isolated equine granulocytes (WBC), radiolabeled with 99mTc-hexamethylpropyleneamine oxime (99mTc-HMPAO) or 111In-oxine, were evaluated in vitro for their labeling characteristics, viability, and phagocytic function over a 6-hour postlabeling period. Mean +/- SD labeling efficiency for 111In-oxine-WBC was 62.2 +/- 15.3%, which was significantly (P less than 0.001) higher than that for 99mTc-HMPAO-WBC (32.0 +/- 17.0%). In vitro elution of radiolabel from cells was significantly (P less than 0.02) greater for 99mTc-HMPAO-WBC at 0.5, 2, and 4 hours, but was not significantly different from elution of radiolabel for 111In-oxine-WBC at 6 hours. Viability, assessed by trypan blue dye exclusion, for 99mTc-HMPAO-WBC, 111In-oxine-WBC, and nonlabeled control WBC ranged from 97 to 100%, and was not significantly different among groups. Cell function was assessed by use of a phagocytosis assay and was reported as phagocytic index. The phagocytic index ranged from 0.86 to 0.96 for 99mTc-HMPAO-WBC, and from 0.76 to 0.97 for 111In-oxine-WBC. The phagocytic index was not significantly different at 0.5, 2, or 4 hours, but was significantly (P = 0.038) greater at 6 hours for 99mTc-HMPAO-WBC. Because of the superior imaging characteristics of 99mTc-HMPAO-WBC and equal or better labeling characteristics than those for 111In-oxine at 6 hours, 99mTc-HMPAO-WBC appear to be a good alternative to 111In-oxine-WBC.

Topics: Animals; Cell Survival; Cells, Cultured; Granulocytes; Horses; Isotope Labeling; Leukocyte Count; Organometallic Compounds; Organotechnetium Compounds; Oximes; Oxyquinoline; Phagocytosis; Technetium Tc 99m Exametazime

A 54-y old women with earlier replacement of the mitral and aortic valves and clinical signs of localized endocarditis was studied with 99mTc-labelled anti NCA-95 antibody. Whereas echocardiographic findings were negative, increased radionuclide uptake was observed left parasternal over the mitral valve as a sign of prosthetic valve endocarditis. This result could be confirmed by a similar study with leukocytes labelled in vitro with 111In-oxine.

Topics: Antibodies, Monoclonal; Antigens, Neoplasm; Cell Adhesion Molecules; Endocarditis; Female; Heart Valve Prosthesis; Humans; Indium Radioisotopes; Leukocytes; Membrane Glycoproteins; Middle Aged; Mitral Valve; Organometallic Compounds; Organotechnetium Compounds; Oximes; Oxyquinoline; Radionuclide Imaging; Technetium Tc 99m Exametazime

Technetium-99m-HM-PAO [( 99mTc]HM-PAO) leukocyte and indium-111-oxine (111In-oxine) leukocyte scanning were carried out simultaneously in 41 patients at 4 hr and 24 hr after reinjection to determine whether the 4-hr 99mTc scan could replace the 24-hr 111In scan for detecting intraabdominal sepsis. Abdominal infection was confirmed in 12 cases. The 4-hr 99Tc-leukocyte scan, the 4-hr 111In-leukocyte scan, and the 24-hr 111In-leukocyte scan yielded a sensitivity of 100%, 67%, and 100%, respectively, and a specificity of 62%, 90%, and 86%, respectively. The 24-hr 99mTc-leukocyte scan also produced a sensitivity of 100%, but it was falsely positive in all 29 cases without infection due to physiologic bowel uptake. False-positive 4-hr 99mTc-leukocyte scans were also produced by physiologic bowel uptake in seven cases all of whom had true-negative 4-hr and 24-hr 111In-leukocyte scans. Because of the high incidence of false-positive 4-hr [99mTc]HM-PAO leukocyte scans, it was concluded that they could not replace 24-hr 111In-leukocyte scans for detecting intraabdominal sepsis, and that serial 99mTc leukocyte scans starting earlier than 4 hr after reinjection must be evaluated.

Topics: Abdomen; Bacterial Infections; False Positive Reactions; Female; Humans; Hydroxyquinolines; Indium Radioisotopes; Leukocytes; Male; Middle Aged; Organometallic Compounds; Organotechnetium Compounds; Oximes; Oxyquinoline; Radionuclide Imaging; Technetium Tc 99m Exametazime; Time Factors

Topics: Antibodies, Monoclonal; Cell Movement; Granulocytes; Hip Prosthesis; Humans; Indium Radioisotopes; Kinetics; Knee Prosthesis; Organometallic Compounds; Organotechnetium Compounds; Osteomyelitis; Oximes; Oxyquinoline; Radionuclide Imaging; Surgical Wound Infection; Technetium Tc 99m Exametazime; Tissue Distribution

Topics: Adolescent; Adult; Aged; Aged, 80 and over; Colon; Female; Humans; Ileum; Indium Radioisotopes; Inflammatory Bowel Diseases; Leukocytes; Male; Middle Aged; Organometallic Compounds; Organotechnetium Compounds; Oximes; Oxyquinoline; Prospective Studies; Radionuclide Imaging; Technetium Tc 99m Exametazime

Topics: Adult; Antibodies, Monoclonal; Antigen-Antibody Reactions; Female; Granulocytes; Humans; Indium Radioisotopes; Infections; Inflammatory Bowel Diseases; Male; Middle Aged; Organometallic Compounds; Organotechnetium Compounds; Oximes; Oxyquinoline; Radionuclide Imaging; Technetium Tc 99m Exametazime; Tissue Distribution

Four patients with the acquired immunodeficiency syndrome (AIDS) and fever were investigated using donor leucocyte scans. The lung/liver and lung/spleen uptake ratios in these patients were compared with the uptake ratios in donor leucocyte scans in seven neutropenic (non-AIDS) patients and five patients who had autologous leucocyte scans performed over the same time period. For all scans indium-111-oxime-labelled leucocytes were used, except for one AIDS patient in whom technetium-99m hexamethyl-propylene amine oxide (HMPAD)-labelled donor leucocytes were used. There were no adverse reactions to the donor cell infusions. Two patients had repeat studies 8 weeks apart (from different donors) without ill effect. There were no differences in the 111In uptake ratios between the three groups. There were three positive studies in the patients with AIDS, and these elucidated the cause of the pyrexia in all three. The negative case is more difficult to confirm, but the clinical course and the absence of focal disease on post-mortem have been taken to support the scan findings. There was no difference in the acceptability of the technique or the distribution of the labelled leucocytes between the AIDS and non-AIDS patients. Donor leucocyte imaging of patients with AIDS is probably more effective and considerably less hazardous for technical staff than autologous leucocyte methods. This study demonstrates that the technique can be applied successfully to patients with AIDS.

Topics: Acquired Immunodeficiency Syndrome; Adult; Aged; Bacterial Infections; Blood Donors; Fever of Unknown Origin; Humans; Indium Radioisotopes; Isotope Labeling; Leukocytes; Middle Aged; Opportunistic Infections; Organometallic Compounds; Organotechnetium Compounds; Oximes; Oxyquinoline; Radionuclide Imaging; Technetium Tc 99m Exametazime

Topics: Angioplasty, Balloon; Blood Platelets; Cells, Cultured; Humans; Indium Radioisotopes; Intermittent Claudication; Organometallic Compounds; Organotechnetium Compounds; Osmotic Fragility; Oximes; Oxyquinoline; Platelet Activation; Radionuclide Imaging; Technetium Tc 99m Exametazime

Topics: Abscess; Colitis, Ulcerative; Crohn Disease; Granulocytes; Humans; Organometallic Compounds; Oximes; Oxyquinoline; Radionuclide Imaging; Technetium Tc 99m Exametazime

31 patients with suspected septic loosening of an endoprosthesis (hip endoprosthesis n = 30; knee endoprosthesis n = 1) were examined with leukocyte scans (10 MBq 111In-oxine: n = 22; 300 MBq 99mTc-HMPAO: n = 9). The results were compared with results of the bacterial growth (n = 22), the histology (n = 12) and of the bone scans (99mTc-MDP: n = 20) which were performed within 4 days. The sensitivity of the bone scan was 100%, the specificity 30% and the diagnostic accuracy regarding a septic loosening of the arthroplasty was 55%. For the leukocyte scans a comparable sensitivity of 100%, but a higher specificity (86%) and accuracy (91%) could be calculated. A false positive leukocyte scan could be observed in a periprosthetic granuloma, an ossifying periarthritis and in a patient with negative bacterial growth with the histological proof of an inflammation.

Topics: Adult; Aged; Bacterial Infections; Female; Hip Prosthesis; Humans; Indium Radioisotopes; Knee Prosthesis; Leukocytes; Male; Middle Aged; Organometallic Compounds; Oximes; Oxyquinoline; Prosthesis Failure; Radionuclide Imaging; Technetium; Technetium Tc 99m Exametazime

The in vitro and in vivo behaviour of 99Tcm-HMPAO (hexamethylpropyleneamineoxime) (n = 12) and 111In-oxine (n = 11) labelled granulocytes, isolated by density-gradient centrifugation (Metrizamide/plasma gradients), was compared in patients with suspected inflammatory diseases. The in vitro elution of both labels and the viability of the labelled cells (99Tcm, 98.5%; 111In, 96.5%) was comparable but the labelling efficiency was different (99Tcm, 44 +/- 13%; 111In, 72.5 +/- 5.5%). In vivo, the lung (t1/2 max: 7.7 min), liver and spleen perfusion patterns were nearly identical; the image quality for detail in 99Tcm scans was superior to 111In images. The blood disappearance curves of 99Tcm and 111In were comparable. In the small number of patients examined all infections could be diagnosed correctly, without false-positive or false-negative results. Disadvantageous is the renal excretion of 99Tcm complexes (3+% over 20 h) with kidney and bladder activity from the beginning of the study. The biliary excretion in half of the patients (n = 6) with unspecific positive small and large bowel visualization and the late intestinal excretion also render the diagnosis more difficult. The recommended best imaging times for abdominal and retroperitoneal inflammations are 30 min to 2 h after injection. Late scans in septic prosthetic joints have disproportionate long acquisition times. As a potential cell labelling compound, 99Tcm-HMPAO has a promising future in comparison to 111In scans because of the good availability of 99Tcm, the image quality and the lower radiation exposure to the patient when lower activities for the early diagnosis of abdominal inflammatory diseases are reinjected.

Topics: Colitis, Ulcerative; Crohn Disease; Female; Granulocytes; Humans; Hydroxyquinolines; Indium Radioisotopes; Inflammation; Isotope Labeling; Joint Diseases; Lung Diseases; Male; Organometallic Compounds; Oximes; Oxyquinoline; Polycystic Kidney Diseases; Radionuclide Imaging; Technetium; Technetium Tc 99m Exametazime

99mTc-hexamethylpropylene amine oxime d,l diastereoisomer (HM-PAO), developed as a diffusible brain imaging agent, labels leukocyte suspensions in saline with an efficiency of 80% using 1-200 micrograms quantities. In dogs, the recovery and survival of reinjected cells in the bloodstream resemble those of 111In-oxine labeled cells at least for several hours. Images in control animals at 18 h show the spleen, liver, marrow, and bladder, minimal pulmonary activity and some gastrointestinal activity. Induced E. coli abscesses and joint inflammatory lesions in dogs are shown on 18 h images. This complex appears promising as an agent for abscess detection in humans. However, strict quality control of this agent is necessary, and it must be used immediately after the 99mTc complex is formed for labeling cells.

Topics: Abscess; Animals; Dogs; Humans; Hydroxyquinolines; Indium Radioisotopes; Leukocytes; Organometallic Compounds; Oximes; Oxyquinoline; Radionuclide Imaging; Technetium Tc 99m Exametazime; Tissue Distribution