A 47-year-old male with seronegative human immunodeficiency virus (HIV) and diabetes mellitus suffered from lower back pain. He was diagnosed with bacterial spondylitis and iliopsoas abscess [Figure 1a]. Multiple antibacterial agents were prescribed, but the lesion did not disappear. M. tuberculosis was detected from the abscess, and caseous granuloma was identified pathologically in surgical specimens of the intervertebral disk [Figure 1b]. He was prescribed the antituberculous agents which were isoniazid 300 mg, rifampicin 600 mg, ethambutol 1000 mg, and pyrazinamide 1500 mg/day. His lower back pain and inflammatory findings improved by the antituberculous therapy.
Two months after starting the antituberculous therapy, he complained of headache, nausea, and staggering. Physical findings on admission were that he was afebrile and did not have stiff neck. A right coordination deficit was identified, and other neurological deficits did not exist. Laboratory findings did not show inflammatory reaction. Chest computed tomography (CT) did not show any cavity lesions. Magnetic resonance (MR) images revealed a nodular enhanced lesion in the right cerebellar hemisphere extending to the vermis associated perifocal edema and bilateral ventriculomegaly [Figure 2]. The lesion showed hypointensity by diffusion- attenuated, weighted images.
Tuberculoma was suspected which appeared de novo or enlarged during the antituberculous therapy that was suggested to be a PR. The therapeutic strategy was a lesionectomy because he presented noncommunicating hydrocephalus, and malignant glioma could not be ruled out completely. Lesionectomy would be thought to relief noncommunicating hydrocephalus, and we did not plan to perform ventricular shunt.
Surgery was performed by a midline occipital approach. A well-circumscribed mass with gray color was identified by opening the cerebellomedullary fissure [Figure 3]. A mass of 3.5 cm was extracted [Figures 3 and 4]. Pathology revealed a caseous granulomatosis at low-power magnification and invasion of lymphocytes and macrophages at high-power magnification [Figure 4a], and those were suggestive findings of past infection of M. tuberculosis. M. tuberculosis was not identified by Ziehl-Neelsen stain. These findings lead to a definitive diagnosis of tuberculoma. Postoperative MR images revealed total removal of the lesion [Figure 4b]. He recovered well from nausea and staggering and was discharged 3 weeks after the operation. He was prescribed antituberculous agents which were isoniazid, rifampicin, ethambutol, and pyrazinamide for the first 2 months and then isoniazid and rifampicin for up to 10 months according to the guideline for the treatment of tuberculosis of central nervous system.