Artifactual measurement of low serum HDL-cholesterol due to paraproteinemia

High levels of serum low density lipoprotein cholesterol (LDL-C) and low levels of high density lipoprotein cholesterol (HDL-C) are well-known risk factors for premature atherosclerotic vascular disease [1, 2]. They are targets for primary and secondary prevention. Interpreting lipid profiles is part of the daily routine for a cardiologist. The most common cause of low HDL-C in western society is metabolic syndrome. More rare are primary lipid disorders (e.g., Tangier syndrome due to an ABCA transporter deficiency or deficiency of apolipoprotein A1) and secondary causes like (ab)use of androgens (Table 1). Extremely low serum HDL levels are associated with an increased risk of death, sepsis and malignancy [3]. A rare but important cause is interference in the biochemical assay by paraproteins, yielding an artifactually low HDL-C measurement result. We present the case of a patient who had his lipid profile repeatedly tested over the course of 4 years and had progressive decline in HDL-C measurements

Connective tissue growth factor is increased in plasma of type 1 diabetic patients with nephropathy

OBJECTIVE - Connective tissue growth factor (CTGF) is strongly upregulated in Fibrotic disorders and has been hypothesized to play a role in the development and progression of diabetes complications. The aim of the present study was to investigate the possible association of plasma CTGF levels in type I diabetic patients with markers relevant to development of diabetes complications. RESEARCH DESIGN AND METHODS - Plasma CTGF levels (full-length and NH2-terminal fragments) were determined in 62 well-characterized patients with type 1 diabetes and in 21 healthy control subjects. Correlations of these plasma CTGF levels with markers of glycemic control, platelet activation, endothelial activation, nephropathy, and retinopathy were investigated. RESULTS - Elevated plasma NH2-terminal fragment of CTGF (CTGF-N) levels were detected in a subpopulation of type I diabetic patients and were associated with diabetic nephropathy. Stepwise regression analysis revealed contribution of atbuminuria, creatinine clearance, and duration of diabetes as predictors of plasma CTGF-N level. Elevation of plasma CTGF-N levels in patients with retinopathy was probably clue to renal comorbidity. CONCLUSIONS - Plasma CTGF-N levels are elevated in type 1 diabetic patients with nephropathy and appear to be correlated with proteinuria and creatinine clearance. Further studies will be needed to determine the relevance of plasma CTGF as a clinical marker and/or pathogenic factor in diabetic nephropath