sodium-pertechnetate-tc-99m and Staphylococcal-Infections

Tc-Human immunoglobulin G ( Tc-HIG) is a well-known radiopharmaceutical for the evaluation of inflammatory lesions. Recently, it has been demonstrated as a new agent for the visualization of the lymphatic system by our group. Our aim was to investigate the feasibility of detection of inflammatory lymph nodes by Tc-HIG lymphoscintigraphy. Ten adult New Zealand rabbits were used as group A. In a baseline study, 37 MBq Tc-HIG (0.1 ml) was injected into both hind legs of the rabbits, and sequential posterior gamma imaging with the rabbits lying prone was performed at 5, 15, 30, 60, 90 and 120 min using a single-headed gamma camera (Toshiba GCA G01 E). One week later, microorganisms ( ) were injected in a volume of 0.1 ml intradermally into the web space between the second and third toes in the bilateral hind legs of each rabbit in order to obtain inflammation in the popliteal lymph nodes. After 4 days, 37 MBq Tc-HIG (0.1 ml) was injected into the hind legs of the rabbits bilaterally, and sequential posterior gamma imaging was performed as described above (second study). Another group of 10 adult New Zealand rabbits (group B) was injected with the same microorganisms in the right hind legs only. After 4 days, scintigraphic imaging was carried out in the same way as described above (third study). Regions of interest were drawn over the injection sites and popliteal lymph nodes on each image for semiquantitative analysis. Count rates for each were calculated and a decay correction was applied. Time-activity curves were generated to show the percentage retention of radioactivity in each region. After the scintigraphic study, some of the group B rabbits were killed by intravenous injection of pentobarbitone (100-150 mg.kg, and both left and right lymph nodes were removed for microscopic examination. On the scintigrams, lymphatic channels and popliteal lymph nodes were visualized within 15 min. In the second study, bilateral popliteal lymph nodes were visualized more clearly than in the baseline study. The right popliteal lymph nodes of the rabbits were more clearly visualized in the third study. Semiquantitative analysis showed a higher percentage uptake of radioactivity in the right compared to the left popliteal lymph nodes in group B rabbits. Microscopic examination of the tissue sections demonstrated inflammation in the right lymph nodes of group B rabbits. In this preliminary study, it was found that Tc-HIG is a new promising agent for the demonstration and e

Topics: Animals; Chromatography, Thin Layer; Humans; Immunoglobulin G; Inflammation; Lymph Nodes; Lymphatic Diseases; Organotechnetium Compounds; Rabbits; Radionuclide Imaging; Radiopharmaceuticals; Sodium Pertechnetate Tc 99m; Staphylococcal Infections

Topics: Aneurysm, Infected; Child; Erythrocytes; Femoral Artery; Humans; Male; Popliteal Artery; Radionuclide Imaging; Sodium Pertechnetate Tc 99m; Staphylococcal Infections

Previous reports on the use of radiolabelled immunoglobulins led us to undertake a pilot experiment in an animal model to investigate the potentials of Tc 99m-immunoglobulin scintigraphy in the detection of infectious foci. Mice infected in one leg with staphylococcus infection were injected with Tc 99m-immunoglobulin, Tc 99m-albumin or gallium citrate Ga 67. The results obtained by scintigraphy suggested a specific accumulation of radiolabelled immunoglobulin at the site of infection. Visualization of the infection and the image quality, especially the 6- and 24-h images, were clearly enhanced after the use of immunoglobulin preparations as compared with gallium.

Topics: Animals; Citrates; Citric Acid; Female; Focal Infection; Gallium Radioisotopes; Hindlimb; Immunoglobulins; Mice; Pilot Projects; Radionuclide Imaging; Sodium Pertechnetate Tc 99m; Staphylococcal Infections; Technetium Tc 99m Aggregated Albumin

Experiments on 9 dogs were staged for a study of a method of early diagnosis of infectivity of vascular prostheses of the abdominal aorta with the help of 99m-Tc-labelled leukocytes. A sterile synthetic vascular prosthesis was used for prosthetics of the abdominal aorta in the 1st control group of animals, a prosthesis, previously infected with St. aureus, was used in the 2nd group, a sterile prosthesis with its subsequent infecting by i.v. injection of St. aureus was used in the 3rd group. The role of antibiotic therapy in infectivity of vascular prostheses was studied on the animals of the 3rd group. A radionuclide study with autologous 99m-Tc-labelled leukocytes was conducted using the Deina-2 camera (Picker). Visualization of the prostheses was unobserved in the 1st control group; in the 2nd group the accumulation of 99m-Tc-leukocytes in the zone of the prosthesis and its visualization on the 4th-5th min. were noted; in the 3rd group the prosthesis was visualized on the 10th-15th min. After antibiotic therapy in the 3rd group visualization of the prosthesis was undetectable. The proposed method permitted visualization of a zone of infection in the early postoperative period, observation of the time course of infection development, and assessment of the efficacy of antibiotic therapy.

Topics: Animals; Blood Vessel Prosthesis; Dogs; Equipment Contamination; Female; Indium Radioisotopes; Leukocytes; Male; Methods; Postoperative Complications; Radionuclide Imaging; Sodium Pertechnetate Tc 99m; Staphylococcal Infections; Time Factors

The utility of radionuclide labeled leukocytes in the demonstration of infection within vascular prostheses was examined. The infrarenal aorta was replaced with a 3 cm Dacron graft in 12 dogs. On the third postoperative day, six of the animals received an intravenous injection of 10(8) Staphylococcus aureus. Labeled leukocyte scans were performed at postoperative days one and three, and then weekly for 8 weeks with indium-111 and technetium-99 labeled autologous leukocytes. When scans showed focal uptake of isotope in the area of prosthetic material, the grafts were aseptically excised and cultured on mannitol-salt agar. Both control and infected animals had retroperitoneal isotope activity in the immediate postoperative period that disappeared by the end of the first week. By the eighth postoperative week, all of the animals that received the bacteremic challenge had both radionuclide concentration in the region of the vascular prosthesis and S. aureus cultured subsequently from the perigraft tissues. None of the control animals had either radionuclide or bacteriologic evidence of infection at the eighth postoperative week. The radiolabeled leukocyte scan is a highly sensitive and specific technique, clinically applicable for the diagnosis of vascular prosthetic infections.

Topics: Animals; Aorta; Blood Vessel Prosthesis; Dogs; Leukocytes; Postoperative Complications; Radionuclide Imaging; Sodium Pertechnetate Tc 99m; Staphylococcal Infections; Technetium