Intracranial tuberculoma in motor cortex: a central cause of isolated unilateral foot drop.

To cite: Panda AK. BMJ Case Rep Published online: [please include Day Month Year] doi:10.1136/bcr-2013010285 DESCRIPTION A 9-year-old girl presented with one episode of focal short lasting nocturnal seizure without impaired consciousness involving right lower limb that persisted for 1 min. This event was neglected by the patient and brought attention on retrospective analysis. There was no history of fever, headache, vomiting, visual blurring or altered sensorium. Twenty days later, she developed foot drop in her right leg which led to problems with walking. There was no history of trauma, hypopigmented patch, sensory loss or radicular pain. Cranial nerve examinations were normal including fundi. Tone was normal in all limbs except in her right ankle which was hypotonic, and the power of right ankle dorsiflexion was 2/5, plantar flexion was 4/5 and intrinsic muscles of foot were 1/5. Power around hip and knees were 5/5. Upper limbs and left lower limb were spared. The right knee and ankle jerks were pathologically brisk with right ankle clonus. She had a high steppage slapping gait with right foot drop. Laboratory investigations were unremarkable except for raised erythrocyte sedimentation rate (42 mm in first hour). Nerve conduction test, needle electromyography and whole spine MRI were unremarkable. MRI (3 Tesla) of brain with axial sequences showed T2 hyperintense, T1 hypointense and diffusion restricted granulomatous lesion with perilesional oedema in the left precentral gyrus (motor cortex) (figures 1–3). Sagittal and coronal section of T1 gadolinium contrast sequences of above lesion revealed a well-circumscribed thickwalled saggy ring enhanced granulomatous lesion (tuberculoma) (figures 4 and 5). There was no other evidence of systemic tuberculosis. Among the cerebral causes of foot drop, parasagittal meningioma, neuroschistosomiasis, high-grade