Tuberculome à localisation inhabituelle: noyau caudé

We report the case of a 30-year old patient with a febrile meningeal syndrome. CSF examination revealed lymphocytic meningitis, white blood cell count was 400 cells/mm3 and hypoglucorachia suggestive of TB meningitis. Brain imaging (CT scan then MRI) (Figure 1 and 2) was performed. It showed cerebral tuberculoma localized at the level of the caudate nucleus. The patient underwent antibacillary treatment with good evolution. Tuberculomas are a rare complication of CNS tuberculosis. Their primary site is the junction of the white and gray matter. Diagnosis is based on imaging. They can be single or multiple. CT scan shows a rounded or oval hypodense or isodense area with rapid contrast enhancement after injection of contrast medium. There may be a peripheral ring-like enhancement of a form similar to that of rosettes . The MRI appearances of tuberculomas and peritumoral edema are hypointense to brain parenchyma on T1 sequence. Following injection of gadolinium CT scan images show classic ring enhancement. In T2 they produce hypointense signal with several punctiform hyperintense signals inside the lesion and an irregular hyperintense peripheral zone corresponding to the oedema. MRI is the investigation of choice for the diagnosis of brain tuberculoma. It is superior to CT scan for the assessment of the extension and of the different components of the lesion (necrotic center, capsule and perilesional œdème).