technetium-tc-99m-exametazime and Streptococcal-Infections

Sydenham's chorea results from group A streptococcus infection and subsequent generation of antineuronal antibodies directed at the caudate nucleus and putamen. Predominantly bilateral, in up to 30% of cases the chorea can be unilaterally restricted. Imaging studies, both structural (magnetic resonance imaging) and functional (positron emission tomography), in patients with bilateral Sydenham's chorea have suggested reversible striatal abnormalities. Two patients with unilateral Sydenham's chorea are presented. Computed tomographic and magnetic resonance imaging were normal in both. However, hexamethylpropylenamine oxime single photon emission tomographic (HMPAO SPECT) studies demonstrated hypermetabolism in the contralateral basal ganglia. Resolution of symptoms in one of the patients coincided with normalization of the SPECT scan. Thus, unilateral striatal hypermetabolism appears to underlie the contralateral chorea observed. A SPECT scan probably should be included in the work-up of new-onset chorea.

Topics: Autoimmune Diseases; Caudate Nucleus; Child, Preschool; Chorea; Dominance, Cerebral; Energy Metabolism; Female; Humans; Male; Putamen; Streptococcal Infections; Streptococcus pyogenes; Technetium Tc 99m Exametazime; Tomography, Emission-Computed, Single-Photon

The authors present a case in which Tc-99m HMPAO labeled autologous leukocytes were used to demonstrate a brain abscess in a patient undergoing evaluation for fever of unknown origin. The abscess was demonstrated on both 1-hour and 24-hour images. The positive 1-hour image led to CT and MRI studies, which are included for correlation. In addition to its previously identified role as a secondary diagnostic test in the differentiation of tumor and abscess, the authors propose that Tc-99m HMPAO is useful as a primary diagnostic tool in the identification of brain abscess. Furthermore, the authors suggest that Tc-99m HMPAO is preferable to In-111 labeled leukocytes because of its better resolution and earlier imaging characteristics.

Topics: Aged; Brain Abscess; Fever of Unknown Origin; Frontal Lobe; Humans; Image Enhancement; Indium Radioisotopes; Leukocytes; Magnetic Resonance Imaging; Male; Radionuclide Imaging; Radiopharmaceuticals; Streptococcal Infections; Streptococcus; Technetium Tc 99m Exametazime; Time Factors; Tomography, X-Ray Computed; Transplantation, Autologous; Whole-Body Counting

During the last few years, labelled leukocyte scintigraphy has become a decisive tool in the diagnosis of bone infections. However, this test may sometimes be deceptive as far as hip prostheses are concerned. The authors have carried out a retrospective study of 62 labelled leucocyte scintigraphies performed for suspected infection of a hip prosthesis. The comparison of the results with the different clinical, biological and radiological factors and the follow up of the patients allows determination of the sensitivity and specificity of this test which are 41% and 100% respectively. The results reported in the literature and the indications for this examination are discussed.

Topics: Adult; Aged; Hip Prosthesis; Humans; Leukocytes; Middle Aged; Organotechnetium Compounds; Oximes; Prosthesis-Related Infections; Radionuclide Imaging; Reoperation; Retrospective Studies; Staphylococcal Infections; Streptococcal Infections; Technetium Tc 99m Exametazime