technetium-tc-99m-exametazime and Autoimmune-Diseases

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

Twenty-two patients with systemic lupus erythematosus and 13 healthy controls were included in a cerebral blood flow study and underwent brain-dedicated single-photon emission computed tomography using 99m technetium-d, l-hexamethylpropylene amine oxime together with a brain computed tomography scan. Plasma levels of antiphospholipid antibodies (lupus anticoagulant and anticardiolipin IgM and IgG antibodies) were also determined. Brain computed tomography showed signs of focal cerebral ischemia in 4 patients (18%), whereas cerebral blood flow by single-photon emission computed tomography was abnormal in 13 of 22 patients (59%), who showed bilateral or monolateral hypoperfusion in the temporo-parietal regions. Patients with abnormal cerebral blood flow had a longer duration of disease than those with normal blood flow (8.9 +/- 1.9 years vs. 5.3 +/- 1.5 years, P < 0.05). Plasma antiphospholipid antibodies were present in 15 patients (68%), but the prevalence was similar in those with normal (6/9, 66%), or abnormal (9/13, 69%) cerebral blood flow. No statistically significant difference in lupus anticoagulant or anticardiolipin antibodies was observed between patients with and without cerebral blood flow abnormalities. Our study shows that patients with systemic lupus erythematosus frequently have cerebral blood flow abnormalities, which could precede those observed by computed tomography. Plasma lupus anticoagulant and anticardiolipin titers were not correlated with normal cerebral blood flow.

Topics: Adolescent; Adult; Antibodies, Anticardiolipin; Autoimmune Diseases; Brain Ischemia; Cerebrovascular Circulation; Cerebrovascular Disorders; Child; Female; Humans; Lupus Coagulation Inhibitor; Lupus Erythematosus, Systemic; Male; Middle Aged; Sensitivity and Specificity; Technetium Tc 99m Exametazime; Tomography, Emission-Computed, Single-Photon; Tomography, X-Ray Computed; Vasculitis