Laboratory medicine in primary care: Paraprotein management
W Stuart A Smellie and Gavin P Spickett explore best practice in the investigation and monitoring of paraprotein bands in blood or urine, look at the pitfalls, and provide a summary of guidance
We present two cases illustrating the use of electrophoresis in the diagnosis and monitoring of plasma cell dyscrasias. The presence of monoclonal protein bands (paraproteins) in myeloma is well recognised; other conditions in which paraproteins may be seen are less well understood, as is the relatively common monoclonal gammopathy of unknown significance (MGUS) often previously referred to as benign paraproteinaemia.
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/min, 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