Case 1

A 58 year old woman was referred urgently to hospital with a three month history of lethargy, weight loss, dysphagia, and nausea. On the day she was seen by her general practitioner she was weak and hypotensive (90/58 mm Hg). Examination showed an underweight woman (body mass index 19) with a blood pressure of 90/60 mm Hg, pulse 90 beats per minute, muscle wasting, no oedema, and no focal neurological signs.

Results of initial laboratory investigations were sodium 128 mmol/l, potassium 5.2 mmol/l, urea 7.2 mmol/l, creatinine 105 µmol/l, total protein 52 g/l, albumin 27 g/l, aspartate transaminase 68 IU/l, alanine transaminase 86 IU/l. Serum immunoglobulins IgG, IgA, and IgM were within the reference range.

A short synacthen test produced blood cortisol concentrations of 254 mmol/l at 0 minutes and 316 mmol/l at 30 minutes. She was given replacement steroids and began to improve.

Investigation of her low serum albumin showed proteinuria (total protein excretion 8.2 g/24 hours). Serum electrophoresis showed no visible paraprotein band, and a subsequent immunofixation was negative. Urine electrophoresis showed a dense albumin band and one additional band, typed by immunofixation as kappa light chains (600 mg/l).

She was referred for nephrology assessment. Serum amyloid component P (SAP) scintigraphy showed heavy amyloid load in spleen and liver. In …