EDITOR, - Jane Patmore and colleagues' lesson of the week raises many issues on the diagnosis and current management of lipid disorders.1 Firstly, several consensus guidelines recommend that a lipid diagnosis should be established before drug treatment is started and that the lipid profile should include measurement of the high density lipoprotein cholesterol concentration.2,3

Secondly, the case reported was complicated by many confounding factors known to influence total and high density lipoprotein cholesterol concentrations, including the administration of β blockers, prednisolone, and high dose oral hormone replacement treatment and the coexistence of renal disease (the patient had received a transplant). These factors would confuse any diagnosis of a primary hyper-(alpha)-lipoproteinaemia. The authors measured the apolipoprotein A1 concentrations, but other apolipoproteins (apolipoprotein A2 (present in high density lipoprotein) and apolipoprotein (a)/ B(sub100)) are independent risk markers for ischaemic heart disease in patients with both normal and abnormal renal function.4 The role of measurements of apolipoprotein in clinical practice is unclear,4,5 and satisfactory reference ranges have not been established in patients with renal disease. Coadministration of immunosuppressive drugs- in this case azathioprine-may also affect liver function.5 Any increase in liver transaminases could potentially make monitoring of adverse biochemical effects of fibrates and statins difficult.

We consider that drug treatment should be withheld from all patients for whom a lipid profile has been obtained but high density lipoprotein cholesterol has not been measured. All necessary investigations should be undertaken to establish the cause of the underlying dyslipidaemia. …