A 45-year-old man with AIDS is admitted to the hospital with a productive cough, fever, and night sweats. An X-ray film of the chest shows an ill-defined area of consolidation at the periphery of the right middle lobe and mediastinal lymphadenopathy. A sputum culture grows acid-fast bacilli. The patient develops severe headache and neck rigidity. Which of the following brain areas is most likely affected by this patient's infection?

Tuberculous meningitis has a predilection for the base of the brain, and infarcts are often found in the distribution of the striate arteries. Inadequately treated tuberculous meningitis results in meningeal fibrosis, communicating hydrocephalus, and arteritis, with the last leading to infarcts. Less often, parenchymal tuberculosis produces tuberculomas (i.e., solitary masses with central caseous necrosis surrounded by granulomatous tissue; choices B, C, D, and E).Diagnosis: Tuberculosis