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  1. Hiroki Matsuura1,
  2. Keiichi Takiue1,
  3. Hikari Nakato1,
  4. Chika Nishihara1,
  5. Erika Sasaki2,
  6. Yuu Suganami1,
  7. Masayuki Kishida1,2
  1. 1 General Internal Medicine, Okayama City Hospital, Okayama, Japan
  2. 2 Endocrinology, Okayama City Hospital, Okayama, Japan
  1. Correspondence to Dr Hiroki Matsuura, General Internal Medicine, Okayama City Hospital, Okayama 700-0962, Japan; superonewex0506{at}

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A 73-year-old man with malnutrition was transferred to the emergency department with hypothermia, severe dehydration, hypotension, diarrhoea and acute renal dysfunction. He had a medical history of mild hypertension and chronic kidney disease. Further evaluation revealed hypernatremia with a serum sodium level of 163 mmol/L. He was treated with lactated lactate solution and his serum sodium level dropped to 143 mmol/L after 36 hours. Five days later, he developed a sudden onset of tremor, dysarthria and progressive loss …

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  • Contributors HM contributed to write manuscript, discussion and patient care. All co-authors also contributed to discussion and patient care.

  • Funding The authors have not declared a specific grant for this research from any funding agency in the public, commercial or not-for-profit sectors.

  • Competing interests None declared.

  • Patient consent for publication Obtained.

  • Provenance and peer review Not commissioned; externally peer reviewed.

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