the clinical presentation of these patients is varied , ranging from headache and focal neurological deficits to personality changes and/or mental deterioration , including memory loss , inattention , confusion , hallucination , and hyperphagia . as a result , these patients are often confused with encephalitis and its sequel , as happened in our patient . the role of surgery is limited , owing to the architectural complexity and depth of location of the lesion . an 8-year - old patient was referred to the pediatric emergency services with complaints of moderate- to high - grade fever for 10 days , 2 months back . on 5 day of fever , the patient developed choreoathetoid movements on right side of the body , which was more severe in the upper limb . few days later , he developed progressive loss of ambulation , cognition , and speech . on examination , he was in a state of altered consciousness ( e2v2m5 ) . however , his vitals were stable . the neurological assessment revealed , increased tone in all four limbs , with exaggerated deep tendon reflexes and bilateral extensor plantar reflex . fundoscopy revealed mild papilledema , pupils were of normal size and reacting to light . his complete hematological profile and serum chemistries were unremarkable . noncontrast computed tomography ( ct ) of the head revealed a bilateral thalamic iso- to hyperdense lesion with moderate hydrocephalus [ figure 1 ] . the mr examination of the brain showed significant swelling of thalamus with diffuse hypointense signal on t1-weighted ( t1w ) imaging and hyperintense signal on t2 and fluid - attenuated inversion recovery ( flair ) sequences [ figure 2 ] . hypointense signals on t1 and hyperintense signal changes on t2w and flair were also present in the basal ganglia , head of the caudate nuclei , and upper brainstem . findings were considered nonspecific and diagnosis of encephalitis was considered , however , bilateral thalamic glioma was the second possibility . noncontrast computed tomography of head reveals bilateral iso- to hyperdense thalamic masses with hydrocephalus and periventricular ooze t2-weighted magnetic resonance imaging reveals bilateral hyperintense thalamic masses with focal hypointensities t1-weighted axial post - contrast image reveals mild peripheral enhancement patient was managed on the lines of encephalitis and its sequelae . he was started on antiepileptic drugs and decongestants to decrease raised intracranial pressure and a low pressure ventricular shunt was inserted . histopathological examination of the biopsy specimen revealed a highly cellular tumor with foci of palisading necrosis [ figure 4a ] and microvascular proliferation [ figure 4b ] . the tumor cells showed marked nuclear pleomorphism and frequent mitotic figures [ figure 4b ] , including atypical forms . on immunohistochemistry , the tumor cells were immunopositive for p53 [ figure 4c ] and were negative for epidermal growth factor receptor ( egfr ) . mib - i labeling index was approximately 60% in the highest proliferating areas [ figure 4d ] . based on these features , a diagnosis of glioblastoma multiforme , world health organization ( who ) grade iv , was arrived at . photomicrographs showing ( a ) a highly cellular tumor with foci of palisading necrosis ( hematoxylin and eosin ( h and e ) , original magnification 400 ) and ( b ) microvascular proliferation ( h and e , original magnification 400 ) . ( b ) the tumor cells display marked nuclear pleomorphism and frequent mitotic figures ( h and e , original magnification 400 ) . ( c ) immunohistochemistry for p53 showed nuclear positivity ( immunohistochemistry ( ihc ) , original magnification 400 ) . ( d ) mib - i labeling index is 60% ( ihc , original magnification 400 ) tracheostomy was done in view of poor glasgow coma scale ( gcs ) considering the need of prolonged ventilatory support . although thalamic tumors constitute between 2 and 5% of all the pediatric intracranial tumors , it is only 1% in adult series . bilateral pediatric thalamic glioblastomas are extremely rare and only five cases are published in the english literature . the largest series on pure thalamic tumors to date is from the necker enfants malades hospital , paris , which reported 69 children treated over a 14-year period . lesions in the ventrolateral thalamus typically manifest with motor deficits , given their close proximity to the internal capsule . the visual signs and symptoms are present in as many as 50% of these patients and are due to involvement of the optic tracts and the lateral geniculate body . the oculomotor deficits are due to involvement of the retrolenticular segment of the internal capsule or the midbrain tegmentum . involvement of the mammillothalamic tracts or the fornices can lead to cognitive dysfunction and memory problems . bilateral thalamic lesions are associated with changes in personality , memory deficits , confusion , hallucinations , hyperphagia , and bradyphrenia . diffuse and bilateral involvement of thalamic nuclei by these tumors makes the surgical therapy very difficult . the role of surgery , hence , is limited and is performed for histological diagnosis as was done in our patient . the role of chemotherapy and radiotherapy is of questionable significance and are utilized as adjuvant therapies . bilateral thalamic tumors are typically treated with radiation therapy , regardless of whether they are histologically malignant . for bilateral thalamic tumors , the prognosis remains relatively poor regardless of tumor histology and treatment . in our patient , left thalamic tumor was biopsied under magnetic resonance imaging ( mri ) guidance . , documented p53 protein accumulation in 75% of high - grade childhood gliomas , and p53 mutation in 38% . pollack et al . , documented increased expression of p53 in about 35% of high - grade gliomas in children , which increased to 58% when only glioblastomas were considered . the authors determined that this feature was an adverse prognostic factor in a cohort of children who were treated uniformly with surgery , radiotherapy , and chemotherapy . on the other hand , egfr amplification is much less common in pediatric glioblastomas compared to adult primary glioblastomas and the reports on egfr protein expression have been quite varied . , who found only very small foci of tumor cells showing egfr immunopositivity in four of 13 glioblastomas . thalamic lesions continue to be a challenging entity to the neurosurgeons , particularly owing to their deep location and complex circuitry . unilateral tumors are increasingly being tackled by the neurosurgeons with an improved patient outcome . however , bilateral thalamic glioblastomas have a very poor prognosis , irrespective of the modality of treatment .