Vitamin B12 reference intervals on Beckman, Roche and Siemens analytical platforms.

Background: Vitamin B12 status is assessed primarily by measuring total serum B12 using competitive binding methods. The lack of availability of a standard material and high-level reference measurement procedure affect the trueness of B12 results; this results in variation between methods. This study aimed to determine the reference intervals for vitamin B12 on three routine analytical platforms.

Comparison of method-related reference intervals for thyroid hormones: studies from a prospective reference population and a literature review.

Introduction Reference intervals are dependent on the reference population, the analytical methods and the way the data are handled statistically. Individual method-related differences have been studied but the comparative differences in reference intervals have not. Methods We studied a reference population of healthy adult subjects and measured free thyroxine and thyroid-stimulating hormone by the four most commonly used analytical platforms used in the UK.

Persistently raised aspartate aminotransferase (AST) due to macro-AST in a rheumatology clinic.

Macrocomplexes between immunoglobins and aspartate aminotransferase (macro-AST) may result in persistently increased AST concentration. The presence of macro-AST in patients has been implicated in unnecessary investigations of abnormal liver function tests. We report the case of a 44-year-old female who presented to the rheumatology clinic with a 12-months' history of constant widespread pain affecting her limbs and was found to have an elevated AST concentration.

Biological variation of cardiac troponin in stable haemodialysis patients.

Background: Patients with end-stage renal failure exhibit a chronic elevation of serum cardiac troponin (cTn) concentration. In order to facilitate the diagnosis of myocardial infarction in these patients, it is necessary to distinguish an increased cTn concentration due to an acute event, from that being a manifestation of chronic elevation. The aim of this study was to gather biological variation data relating to two serum cTn assays, one, a hs-cTnT assay, the other a contemporary sensitive cTnI assay, among stable haemodialysis patients.

Management of severe in-patient hyponatraemia: an audit in two teaching hospitals in Yorkshire, UK.

Background: Hyponatraemia, the commonest electrolyte abnormality amongst in-patients, is associated with increased mortality. Until recently, there has been a lack of international consensus management of patients with severe hyponatraemia.

Aim: We performed a retrospective study in two teaching hospitals in Yorkshire, UK, to evaluate the management of patients with severe hyponatraemia (serum Na ≤ 110 mmol/L) and to assess the frequency of complications observed in this group, in particular central pontine myelinolysis (CPM) and death.

Hepatocellular carcinoma in variegate porphyria: a case report and literature review.

Variegate porphyria is an autosomal dominant acute hepatic porphyria characterized by photosensitivity and acute neurovisceral attacks. Hepatocellular carcinoma has been described as a potential complication of variegate porphyria in case reports. We report a case of a 48-year-old woman who was diagnosed with hepatocellular carcinoma following a brief history of right upper quadrant pain which was preceded by a few months of blistering lesions in sun-exposed areas.

Rosuvastatin: a review of the pharmacology and clinical effectiveness in cardiovascular disease.

Rosuvastatin is a new generation HMG-CoA reductase inhibitor which exhibits some unique pharmacologic and pharmacokinetic properties. It has low extrahepatic tissue penetration, low potential for CYP3A4 interactions and substantial LDL-C lowering capacity and therefore has distinct advantages. We conducted a Medline literature search to identify rosuvastatin papers published in English.