Table 2 Differential diagnosis of Hashimoto’s encephalopathy (along with relevant clinical features and lab investigation)
Sl no. | Category | Disease | Differentiating clinical features (signs and symptoms) | Relevant laboratory investigation |
|---|---|---|---|---|
1 | Infective | Meningitis | Fever, neck stiffness, positive Kernig’s and Brudzinski sign | CSF showing increased WBCs with neutrophilic or lymphocytic predominance; variable protein and glucose levels depending on the micro-organism involved |
Encephalitis | Seizure episode and focal neurologic findings are characteristic; other features may be common | Neuroimaging is required to localise any specific area of inflammation or lesion | ||
2 | Vascular | Cerebral vasculitis | Widespread systemic involvement along with CNS involvement. Present with skin rash, joint pains or fatigue | Cerebral angiography showing inflamed vessels |
Cerebrovascular accidents (CVA)/ transient ischaemic ATTACK | Focal neurologic finding, unilateral or bilateral limb weakness sings of lobar involvement or cranial nerve palsy, bulbar signs, Babinski sign positive | CT scan/MRI showing haemorrhagic or ischaemic lesion in the cerebral area or brainstem | ||
3 | Neoplastic | Tumours of the brain or spinal cord/Metastasis to the brain | Present with focal symptoms, weight loss, anorexia, early morning headache or signs of increased intracranial pressure. Mass effects | Neuroimaging is required to localise the lesion. PET scan to diagnose any metastasis. Other relevant imaging to find the source |
4 | Traumatic | Any road traffic accident involving Brain/spinal cord | Variable depending on area of lesion. Obvious signs and history of injury. Cushing's triad may be present. Basilar skull fracture, ecchymosis of eyes and CSF leak | Comprehensive imaging and screening, |
5 | Metabolic | Toxin induced (can be from substance abuse, prescription drugs or poison) | Variable symptoms depending on the nature of substance | Clinical; urine drug screening |
Hepatic or Uremic Encephalopathy | Asterixis, focal seizures, low urine output, altered sleep wake cycle | Clinical, urea and ammonia levels, | ||
Hypertensive encephalopathy | Variable symptoms (gait disturbance; headache; vomiting) | Serial BP measurements, electroencephalogram (EEG), ECG | ||
Nutritional Encephalopathy (glycopenic, Wernicke’s) | Drowsiness, autonomic hyperactivity, sweating, confusion, ataxia, nystagmus | Blood glucose levels or vitamin B1 levels. In neuroglycopenia MRI brain may show T2 hyper intensity in basal ganglia, thalamus, cortex and splenium involvement may show ‘boomerang sign’ | ||
6 | Autoimmune | Anti-NMDAR Encephalopathy | Flu-like illness, along with encephalopathic symptoms and then progression to psychosis, paranoia or agitation | anti-NMDAR antibody + in CSF and/or serum, EEG |
Paraneoplastic limbic encephalitis | Associated with an underlying malignancy of lung or breast, amnesia, complex seizures and temporal lobe involvement | Anti-Hu+, anti-Ma+ in CSF and/or serum, EEG showing epileptic activity | ||
Paraneoplastic cerebellar degeneration | Associated with an underlying malignancy of lung, ovary or breast; bulbar palsy along with vertigo or tremor | Anti-Yo, anti-Hu, anti-Ri antibodies in csf and/or serum | ||
Hashimoto's encephalopathy | Altered sensorium, stroke-like episode, myoclonus, seizures, vertigo, headache | Anti-TPO antibodies in CSF and/or serum, MRI enhancement in basilar regions | ||
7 | Degenerative | Creutzfeldt–Jakob disease | Behavioural change, psychosis, dementia, involuntary movements and coma | EEG showing periodic sharp wave pattern, CSF having 14–3–3 protein |