Fig. 1

Progressive cerebral toxoplasmosis on interval neuroimaging. Serial magnetic resonance imaging (MRI) of the brain using sagittal T1 weighted images. At initial presentation there was (a) a solitary rim-enhancing lesion in the left posterior frontal lobe with moderate surrounding vasogenic odema and a 3.5 cm midline shift to the right. The patient had 4 weeks of therapy with oral sulfadiazine and pyrimethamine. Follow-up imaging showed (b) a persistent lesion in the left posterior frontal lobe as well as new miliary lesions in the cerebral hemispheres bilaterally and involvement of central grey structures including the right lentiform nucleus and thalamus. These findings were most consistent with disseminated toxoplasmosis. Four and a half months after the initial presentation and 4 weeks after a reduction to maintenance therapy the patient represented with nausea, headache and loss of consciousness and imaging showed (c) a new ring enhancing lesion in the right temporal lobe and persistent diffuse military nodules