a minor change in the thyroid hormone concentration has been reported with changes in cognitive and affective functions . hashimoto 's encephalopathy was first reported in 1966 and was associated with hashimoto 's thyroiditis . although it is a controversial disorder , hashimoto 's encephalopathy is considered an autoimmune disease because of its association with immunological disorders , such as myasthenia gravis , primary biliary cirrhosis , and pernicious anemia . hashimoto 's encephalopathy , an unusual neurological disorder with female preponderance , has its typical onset in the fifth decade of unclear etiology , pathogenesis , and management . hashimoto 's encephalopathy presents with neurological manifestations such as generalized / focal tonic - clonic seizures , status epileptics , myoclonus , stroke , hyperreflexia , and tremors . neuropsychiatric manifestations such as psychosis , visual hallucination , paranoid delusion , mania , depression , dementia , and catatonia have been reported in 25 - 36% patients . these manifestations respond well to steroids rather than the conventional treatment , highlighting an autoimmune origin of the disorder . although hashimoto 's encephalopathy is rare among the pediatric group , it is a diagnostic challenge in child psychiatry and neurology . managing the symptoms of this condition is often difficult because of the unpredictable nature of hashimoto 's thyroiditis . in a recent review , only 50 cases aged < 18 years were identified among 300 pubmed articles until july 2013 . we report the first case of atypical presentation of hashimoto 's encephalopathy in an adolescent who recovered successfully with nonsteroid agents and levothyroxine . a 16-year - old girl presented with acute onset of sadness of mood , decreased interest to work and pleasurable activities , irritability , aggressiveness and abusiveness , impulsivity , reduced appetite , easy fatigability , and sleep disturbance , and was unable to concentrate on work for more than a day . on mental status examination , she was agitated , irritable , hostile , impulsive , emotionally labile , and unable to sustain attention . she was premorbidly well - adjusted with an unremarkable developmental and familial history of mental and thyroid illness . five months back , she noticed a small swelling on her thyroid region along with menstrual irregularities called oligomenorrhea and menorrhagia . her thyroid function tests were suggesting hypothyroidism , which was treated with homeopathic medicine [ table 1 ] . her brain magnetic resonance imaging ( mri ) findings demonstrated infarcts in the bilateral gangliocapsular region and left frontal periventricular deep white matter lesion [ figure 1 ] . her ultrasonography ( usg ) of the thyroid revealed a well - defined cystic lesion measuring 3.8 mm  3.2 mm in the right thyroid lobe , followed by fine needle aspiration cytology of swelling , indicating lymphocytic thyroiditis . anti - thyroid peroxidase antibody levels were elevated to 289 iu / ml . the erythrocyte sedimentation rate ( esr ) increased to 50 mm / h with a slight increase in the leucocyte count . her liver function test , renal function test , electrocardiogram , chest x - ray , usg of the abdomen and pelvis , and electroencephalogram were normal . laboratory findings in the index case axial magnetic resonance images of brain demonstrating infarcts in the bilateral gangliocapsular region and left frontal periventricular deep white matter . ( a ) t1-weighted magnetic resonance imaging . ( b ) t2-weighted magnetic resonance imaging she was initially administered fluoxetine 20 mg / day , which was increased gradually to 40 mg / day . however , she showed no improvement in depressive symptoms and impulsivity . on the basis of laboratory findings and responses to drugs , we considered treatment - resistant depression secondary to hashimoto 's encephalopathy . the patient was administered levothyroxine for the thyroid state and aspirin as an anti - inflammatory agent . adding levothyroxine ( 50 g / day ) with aspirin ( 150 mg / day ) for a week resolved her symptoms completely . her elevated esr and antimicrosomal antibodies returned to normal , and she remained in the euthyroid state with a normal sensorium and behavior for approximately 3 years . hashimoto 's encephalopathy is a rare neurological disorder that occurs primarily in the fifth decade with a male to female ratio of 1:4 . it is mainly present in two subtypes : a sudden vasculitis type ( up to 25% cases ) and diffuse progressive type ( up to 75% patients ) characterized by cognitive decline , dementia , confusion , and psychiatric manifestation . in the index case , the patient 's clinical course was more consistent with the sudden vasculitis type because of the abrupt onset of depressive symptoms without a focal neurological deficit and mri findings . most common presentations reported include a neurological presentation , the involvement of the pyramidal tract , seizure , and tremor in the descending order . the neuropsychiatric presentation that includes schizophrenia - like psychotic disorder , mania and depression was reported with lower incidence . pathogenesis of neuropsychiatric manifestation in hashimoto 's encephalopathy remains unknown , and no correlation exists between the concentration of thyroid antibodies and severity of symptoms . the formation of autoantibodies against the n - terminal of -enolase ( nae ) may cause infarcts in the bilateral gangliocapsular region and left frontal periventricular deep white matter lesion in our case . the -enolase antigen is found in both endothelial cells of the blood vessel and thyroid gland , indicating the possibility of an underlying autoimmune vasculitis mechanism . therefore , autoantibodies against the nae may be a potential biomarker of hashimoto 's encephalopathy , and this possibility is being supported by most recently published studies in japan . hashimoto 's thyroiditis is characterized by bouts of hypothyroid , euthyroid , and hyperthyroid states . thus , one should highly suspect a possibility of hashimoto 's encephalopathy in a nonresponsive patient and a patient showing an initial response followed by unresponsiveness to conventional antidepressants . in most recently published reviews , the clinical response was observed in 98% patients treated with steroids , 92% with steroids and levothyroxine , and 67% with levothyroxine . however , only a few have responded well with mood stabilizers , antidepressants , and antipsychotics . the role of steroids in the acute management of ischemic the recently published cochrane review recommends that steroids , considered magic drugs in neurology in the past , play no active role in the management of acute ischemic stroke . moreover , they increase the risk of gastrointestinal bleed , infection , and hyperglycemia . the long - term use of steroids , which is often required in hashimoto 's encephalopathy , predisposes to several side effects including hypertension , osteoporosis , cataract , cushing syndrome , and growth retardation . the index case appears unique in this aspect because the patient responded well when levothyroxine and nonsteroidal anti - inflammatory drug ( nsaid ) ( aspirin ) along with fluoxetine was used to treat her depressive symptoms . although using nsaids has been attempted in the management of chronic thyroiditis , to the best of our knowledge , response is not documented for any other case report or study with the neuropsychiatric presentation . in addition to the anti - inflammatory properties of aspirin , it is an antiplatelet drug , which may be helpful in preventing further infarcts and procrastinating the relapsing and remitting nature of the illness . hashimoto 's encephalopathy , a rare disorder , is unrelated to the thyroid status of a patient . most patients present with variable neuropsychiatric manifestations and course , indicating pathogenesis through both autoimmune and vasculitis mechanisms . they may have treatment - resistant psychiatric and neurological illnesses and respond dramatically to steroids with serious and potential side effects ; however , aspirin or other nsaids along with levothyroxine , mood stabilizers , and antipsychotics may be considered for treatment . a psychiatrist should be aware of this often unrecognized entity to ensure accurate diagnosis and timely treatment , particularly among the pediatric group .
hashimoto 's encephalopathy is usually underdiagnosed and untreated because of complex neuropsychiatric manifestation . 
 we report a case of an adolescent female with hashimoto 's encephalopathy who responded well to a combination of aspirin and levothyroxine . a 16-year - old girl presented at psychiatric emergency services with a depressive episode , menstrual irregularities , and a 5-month past history of thyroid swelling . on clinical examination 
 , she was in a euthyroid state with insignificant neurological history . however , her previous investigation revealed a hypothyroid state . 
 her magnetic resonance imaging findings demonstrated infarcts in the bilateral gangliocapsular region and left frontal periventricular deep white matter lesion . 
 ultrasonography of the thyroid and fine needle aspiration cytology confirmed lymphocytic thyroiditis . 
 anti - thyroid peroxidase ( 289 iu / ml ) antibody titer was elevated ( 289 iu / ml ) . 
 her depressive symptoms responded well to antidepressants , mood stabilizers , nonsteroidal anti - inflammatory drugs , and levothyroxine . 
 she remained in the euthyroid state and then in the euthymic state for 3 years . 
 hashimoto 's encephalopathy is steroid - responsive encephalopathy . 
 most researchers have observed a dramatic response to steroids with or without levothyroxine . a clinician may consider aspirin as an alternative to a steroid in long - term management to avoid steroid - related side effects and contraindications .