4th April 2024

A 24-year-old man who is known to have bipolar disorder was sectioned under Section 5 (2)

A 24-year-old man who is known to have bipolar disorder was sectioned under Section 5 (2) for psychiatric assessment. He complained of increased thirst and polyuria. His random glucose test was 11.2 mmol/L. His sodium level was 163 mmol/L, potassium was 5.7 mmol/L, urea 5.4 mmol/L, creatinine 83 micromol/L and urine osmolality was 429mOsmol/kg. He had a water deprivation test and showed that urine osmolality was 437mOsmol/kg even after he was given desmopressin. What is the likely cause of his condition?

Select the SINGLE most appropriate option from the list below. Select ONE option only.