Annals of clinical biochemistry
-
Ann. Clin. Biochem. · Nov 2008
A rapid rise in circulating pancreastatin in response to somatostatin analogue therapy is associated with poor survival in patients with neuroendocrine tumours.
To assess the value of pancreastatin as a predictive factor for identifying patients with neuroendocrine tumours (NETs) who respond poorly to somatostatin analogues. ⋯ This study endorses the finding that pancreastatin is a useful prognostic indicator of neuroendocrine disease. On commencement of treatment, one-third of the subjects showed an immediate negative pancreastatin response to somatostatin analogues, which was associated with poor survival. This is the first study to document such an association. These findings have significant therapeutic consequences. In the presence of a rapidly rising pancreastatin alternative, treatment modalities should be sought.
-
Ann. Clin. Biochem. · Nov 2008
Uncertainty of sweat chloride testing: does the right hand know what the left hand is doing?
Although analytical variation in sweat electrolyte testing can be easily estimated, there is limited data on total variation. This study aims to evaluate the total variation of the sweat test by measuring the difference between sweat electrolyte values in specimens obtained simultaneously from two sites. Chloride is recommended in published guidelines as the only discriminant for the diagnosis of cystic fibrosis, and sodium may be measured as a guide to the adequacy of collection and analysis. ⋯ In patients with intermediate chloride concentrations; in different age groups; and when those tests with a difference between sodium and chloride concentration of more than 15 were excluded, minimal differences in these figures were observed. Use of strictly defined cut-off points to discriminate between normal and intermediate electrolyte values, and between intermediate and raised electrolyte values, does not reflect the variation in sweat electrolyte content found within an individual patient. This has important implications for reporting.
-
Ann. Clin. Biochem. · Sep 2008
Case ReportsGlucose interference in direct ion-sensitive electrode sodium measurements.
Circulating sodium concentration is commonly measured by both direct and indirect ion-sensitive electrode (ISE). We describe an unusual case with a high elevation of serum glucose (162 mmol/L) where direct ISE sodium measurement was 9 mmol/L higher than the indirect measurement in the absence of any cause for pseudohyponatraemia. ⋯ This effect was insufficient to account for the entire difference between the measurements seen in the patient, indicating that other factors, for example pH and bicarbonate concentration, must also be involved. This effect may influence interpretation of sodium status in patients with gross hyperglycaemia.
-
Ann. Clin. Biochem. · May 2008
C-reactive protein and procalcitonin concentrations in bronchoalveolar lavage fluid as a predictor of ventilator-associated pneumonia.
Diagnosis of ventilator-associated pneumonia (VAP) is difficult. The usefulness of high-sensitivity procalcitonin (ProCa-S) and high-sensitivity C-reactive protein (CRPH) in bronchoalveolar lavage (BAL) fluid and serum in the prediction of VAP was determined. ⋯ Both the ProCa-S and the CRPH kits can be used for assessing the concentration of PCT and CRP in BAL fluid, respectively. PCT and CRP concentrations in BAL fluid appeared to be of no additional value in the diagnosis of VAP.