Background The pneumatic tube system (PTS) has been implicated in inducing haemolysis. It is not known whether certain sample types are more susceptible to haemolysis than others. We assessed the level of haemolysis in commonly used sample types in the clinical biochemistry department when transported through the PTS.

The method of HbA1c standardization used determines the degree of correction required and a consensus approach is recommended. Implementation will assist extrapolation from research-based evidence to local practice. Associated changes to patient management must come under the jurisdiction of the physicians responsible for the diabetic service.

Background The cardiac troponins have been shown to be sensitive and specific biochemical markers of myocardial infarction and highly prognostic for future adverse events in patients with acute coronary syndromes. There have been reports suggesting that haemolysis causes a negative interference in the cardiac troponin T (cTnT) assay but the mechanism(s) involved remain unknown. Here we show the effects of haemolysis and haemoglobin per se on the cTnT assay.

Purple pigment extracted from the urinary catheters and collecting bags of two elderly female patients was analysed by a variety of chemical techniques, including mass spectroscopy and nuclear magnetic resonance. Although previous studies identified the pigment as indigo, we failed to confirm this. Our analysis also demonstrated that indicanuria is not a requirement for the production of the pigment and furthermore indicates that the molecular structure of the pigment is either a steroidal or bile acid conjugate.

Serial measurements of serum amylase, lipase and ionized calcium were made in a prospective study of 17 patients with acute pancreatitis. The mean serum ionized calcium was significantly below the normal range for the first 24 h and had returned to normal after 48 h. There was no correlation between serum ionized calcium and paired calcium corrected for albumin during the first 36 h of the study, but they were correlated for the remainder of the investigation. Serum lipase and ionized calcium levels were just significantly correlated over the first 3 days (r = -0.44; t = 2.3; P less than 0.05; d.f. 22), but failed to reach correlation over the whole period of study (r = -0.34; t = 2.0; d.f. 31). These data establish a significant drop in directly measured ionized calcium early in an attack of pancreatitis, which is not seen in the paired corrected calcium values. Furthermore, the drop is correlated with serum lipase, although this is weak and other factors must be involved in the hypocalcaemia.