Electrolyte abnormalities with a fatal implication.

A 72-year-old caucasian male presented with a 1-month history of decreased appetite, 6 kg weight loss with alteration in pattern of micturition; namely a tendency to pass most of his urine overnight, estimated at 2 l to 2.5 l. He also gave a 1-week history of progressive ankle swelling. Over this period of time he felt increasingly clumsy on his feet especially on turning abruptly. He denied fever, sweats, myalgia, arthralgia, prostatic and gastrointestinal symptoms. He was a non-smoker, infrequently drank alcohol and was a retired businessman. His past medical history included a diagnosis of prostatic carcinoma made 18 months prior to his current presentation. He had been treated with hormonal medication and subsequently TURP 4 months after diagnosis. He was under urological follow-up with a recent PSA value of 0.1 mgul. On clinical examination he was a thin gentleman with a single non-tender lymph node in the left supraclavicular space. Urinalysis revealed 3q glucose only. Skin turgor was reduced, extremities were cold and he had a sinus tachycardia with an occasional ectopic beat. Heart sounds were normal, blood pressure 140u80 mmHg with no postural drop; he had 1q ankle oedema only. Auscultation of his chest was normal, abdominal examination unremarkable. Neurological examination revealed gait ataxia on heel-toe testing only. Current medication prescribed by his general practitioner included Sando-K 2 tabs qds, Slow sodium 2 tabs qds. Initial investigations were as follows: sodium 135 mmolul, potassium 2.9 mmolul, urea 7.2 mmolul, creatinine 115 mmolul, bicarbonate 35 mmolul, corrected calcium 2.34 mmolul, phosphate 0.86 mmolul, albumin 29 gul, magnesium 0.78 mmolul, random glucose 8.5 mmolul, creatinine clearance 38 mlumin, proteinuria 0.36 gud, PSA 1.1 mgul, CRP 1.7 mgul, Hb 13.6 gudl, wcc 7.9.10ul, platelets 210.10ul. Twentyfour hour urinary electrolyte values were sodium 112 mmoluday (50–200), potassium 121 mmoluday (30–100), calcium 8.9 mmoluday (2.5–7.5) and magnesium 2.7 mmoluday (3.0–5.0) with a total volume of 2.7 l.