Metabolic syndrome, endothelial injury, and subclinical atherosclerosis in patients with systemic lupus erythematosus.

OBJECTIVES: To study the link between metabolic syndrome (MetS), endothelial injury, and atherosclerosis in patients with systemic lupus erythematosus (SLE). METHODS: Consecutive SLE patients without a history of arterial thrombosis were screened for atherosclerosis at the carotid and coronary arteries by B-mode ultrasound [intima-media thickness (IMT)] and multidetector computed tomography (MDCT) scan (Agatston calcium scores), respectively. Plasma levels of homocysteine, high-sensitivity C-reactive protein (hsCRP), soluble vascular cell adhesion molecule (sVCAM)-1, P-selectin, and soluble thrombomodulin (sTM) were assayed. Patients were stratified according to the National Cholesterol Education Program (NCEP) Adult Treatment Panel III (ATP III) criteria for MetS, using the Asian criteria for abdominal obesity. Risk factors for atherosclerosis were studied. RESULTS: Of the 123 SLE patients (93% women; age 47.9+/-11 years; SLE duration 10.9+/-7.0 years) studied, 20 (16.3%) had MetS. The prevalence of MetS in the SLE patients was significantly higher than in 492 age- and sex-matched healthy controls (9.6%; p=0.03). Coronary calcification and abnormal carotid IMT were detected in 38 (31%) and 72 (59%) of SLE patients, respectively. Patients with MetS had a significantly higher Agatston score (69.5+/-95 vs. 16.4+/-57; p=0.03) and a numerically higher carotid IMT (p=0.43) than those without. In a logistic regression model, the MetS [odds ratio (OR) 3.11, 95% confidence interval (CI) 1.01-9.59, p=0.049] was associated with coronary atherosclerosis after adjustment for age and other risk factors. In addition, patients with MetS had significantly higher levels of hsCRP (p=0.002), homocysteine (p=0.03), and sTM (p=0.01). CONCLUSIONS: The MetS is more prevalent in SLE patients than the general population and is associated with endothelial injury and coronary atherosclerosis. More aggressive control of risk factors is justified in these patients.

Macroprolactin-a cause of pseudohyperprolactinaemia.

Macroprolactin is a complex of immunoglobulin G and monomeric prolactin with little biological activity in vivo. Macroprolactin cross-reacts in modern commercial prolactin assays, however, leading to pseudohyperprolactinaemia. This report is of three patients with macroprolactinaemia and the untoward consequences if this benign condition is misdiagnosed as genuine hyperprolactinaemia are discussed. One adult and one child without symptoms of hyperprolactinaemia were incidentally found to have elevated serum prolactin levels, one of whom had a pituitary incidentaloma. Repeat prolactin measurement after polyethylene glycol precipitation showed that the majority of circulating prolactin was macroprolactin. The third patient had galactorrhoea and pituitary microadenoma. Polyethylene glycol study showed that macroprolactinaemia exists simultaneously with genuine hyperprolactinaemia leading to falsely high serum prolactin levels. The recognition of this relatively common and benign condition is important in order to avoid misdiagnosis and unnecessary investigations and treatment. Particular attention must be paid to patients in whom the clinical and radiological findings are incompatible.

Glycerol kinase deficiency presenting with hypodipsia, osmotic diuresis and severe hypernatraemia.

A Chinese boy with glycerol kinase deficiency is reported. His presentation with severe hypernatraemia secondary to hypodipsia and glycerol-induced osmotic diuresis is unusual and not previously described in the literature.