POC16 Syndrome of inappropriate antidiuretic hormone precipitated by steroid responsive demyelinating neuropathy

A 68-year-old gentleman was admitted with confusion and unsteady gait following a flu-like illness. Medical history included hypertension and benign prostatic hypertrophy. Four months ago, family physician started prednisolone 30 mg OD for suspected polymyalgia rheumatica (ESR=46 mm/h) and inflammatory peripheral neuropathy. Prednisolone was gradually tapered down to 15 mg OD. On admission GCS was 12/15, sodium (Na)=100 mmol/l, he was euvolemic with normal renal function. Osmolality of serum=218 mOsm/l and urine=630 mOsm/l, urine Na=45 mmol/l, led to diagnosis of syndrome of inappropriate antidiuretic hormone (SIADH). Intensive care management included withdrawal of naproxen, bendroflumethiazide and irbesartan. Serum Na was increased slowly (