A 35-year-old male presented to the emergency department after a tonic-clonic seizure. There was no significant past medical or surgical history. His physical examination was unremarkable, with no fever or focal neurological signs. In the previous 6 months, he reported anorexia and unintentional weight loss of 8 kg, with no other constitutional signs or symptoms. Brain MRI disclosed three ring-enhancing T1 and T2 hypointense cortical lesions, two located in the right frontal lobe and one in the left occipital lobe, associated with vasogenic oedema and absent leptomeningeal enhancement (Figure 1). Based on the imagiological findings, infectious abscesses and metastatic deposits were considered the most probable etiologies. In subsequent diagnostic workup, abdominal CT revealed massive mesenteric infiltration and innumerous lymphadenopathies; therefore neoplastic peritoneal carcinomatosis was first considered. Chest CT and further radiological examination were unremarkable, excluding other organs involved.
Histological examination of the mesenteric lesions revealed multiple noncaseating perivascular granulomas (Figure 2). The polymerase chain reaction (PCR) performed in the tissue specimen was positive for Mycobacterium tuberculosis, thus confirming the diagnosis of disseminated tuberculosis of CNS and peritoneum. Extensive laboratory workup for underlying acquired or hereditary immunosuppression was negative, including human immunodeficiency virus testing, immunoglobulin levels, and lymphocyte subset counts. Acid fast bacilli smear, cultures and PCR from sputum, CSF, and blood were negative. The patient was started on tuberculostatic treatment with adjunctive corticosteroids, in a four-drug regimen during the first two months, followed by additional two-drug regimen in the subsequent eight months. He had a favorable outcome, with complete regression of both cerebral and peritoneal lesions.