Title: Metabolic Encephalopathy in Elderly with a Special Focus on Thyroid Function and Hashimotos Encephalopathy

Authors: Sunil Prasobh P, VS Vineetha, Praveen P

 DOI:  https://dx.doi.org/10.18535/jmscr/v5i10.13

Abstract

Objective: Metabolic encephalopathy is a common cause for morbidity and mortality in elderly. Metabolic disturbances are frequent causes of impaired consciousness and their presence must always be considered when there are no focal signs of cerebral disease. An underdiagnosed but potentially treatable cause of metabolic encephalopathy in elderly is Hashimoto’s encephalopathy (HE). It has huge clinical relevance since it is not uncommon and shows very good response to immunosuppressive treatment. The aim of the study was to analyse the various causes of metabolic encephalopathy in elderly patients. Various presenting features of encephalopathy particularly involuntary movements have also been studied. Cases of Hashimoto’s encephalopathy have been specifically sought for and looked into to characterise the specific clinical manifestations that can point towards its diagnosis.

Materials and Methods: Our study was a hospital based descriptive study conducted in elderly patients above the age of 60 years admitted with altered sensorium. Patients with documented sepsis, hepatic failure ,renal failure,  cerebrovascular accident, CNS infection and head injury were excluded from the study. A thorough clinical examination including detailed neurological examination was done. Blood was sent for investigations including serum electrolytes, hepatic, renal and throid function tests. Those patients who did not had any obvious cause for encephalopathy and not responding to treatment were further evaluated with anti TPO antibodies in CSF.

Results: Of the 132 patients enrolled in the study there were 55males (41.7%) and 77 females (58.3%). Seizures was seen in 15.9% and myoclonus in 3.8% patients. Study showed that 92.4% of patients had hyponatremia and 7.6% had normonatremia. The patients having blood glucose values above 500 mg% and below  50 mg% were 4.5%, and 7.6%. Thus our study showed 7.6% of patients had hypoglycaemic encephalopathy Thyroid status of the patients  showed that clinical hypothyroidism was seen in 3.8% and subclinical hypothyroidism in 15.4%. Majority of the patients were euthyroid(80.8%).The CSF examination showed 14 patients (10.6%) positive  for anti TPO antibodies and  were diagnosed to have hashimotos encephalopathy.Among the patients with hashimotos encephalopathy 71.4% were females , 57.2 % patients had abnormal movements  at presentation , 64.3 % patients had hyponatremia  and 78.5 %  had  a euthyroid status.

Conclusion:  Hyponatremia and altered blood glucose levels were the major causes leading to metabolic encephalopathy in elderly patients. About 10.6% of the elderly patients presented with hashimotos encephalopathy. Abnormal movements were an important presenting feature of hashimotos encephalopathy. A Significant proportion of patients with hashimotos encephalopathy had  euthroid status. A high level of clinical suspicion is needed for the diagnosis, as it is a treatable condition.

Keywords: Hasimotos encephalopathy, seizures, anti TPO antibodies, hyponatremia, euthyroid.

 

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Corresponding Author

Dr Praveen. P

Dept of Internal Medicine, Government Medical College,

Thiruvananthapuram-695011 Kerala, India

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