The renal response to exogenous parathyroid hormone in treated pseudohypoparathyroidism.

Resistance to the renal actions of parathyroid hormone (PTH) in pseudohypoparathyroidism (PsH) may be improved after treatment with vitamin D or its metabolites, but reports conflict. We have examined the renal response to infusion of 35 micrograms of 1-38 PTH in patients with PsH type I (n = 8) and PsH type II (n = 1) during treatment and related this to prevailing endogenous serum PTH and calcium levels. Nine patients with postsurgical or idiopathic hypoparathyroidism (HP) served as controls. The urinary cAMP increase (delta cAMP) was lower (p < 0.001) in the PsH type I (175 +/- 6.4 nmol/l glomerular filtrate) than in the HP group (3251 +/- 515 nmol/l glomerular filtrate). delta cAMP in the PsH type I subjects was dependent on endogenous PTH concentrations (r = -0.76; p = 0.046) and serum calcium (r = 0.74; p = 0.037). Phosphaturic responses (expressed as % decrease in TmPO4/glomerular filtration rate) were lower (p = 0.013) in the PsH type I (28.8 +/- 3.75) compared with those of the HP patients (43 +/- 3.48). The phosphaturic responses in the PsH type I patients were strongly dependent on endogenous PTH (r = 0.94; p < 0.001) and serum calcium levels (r = 0.94; p < 0.001) so that the responses of subjects with normal or low PTH levels were no different (p = 0.16) from the HP group. Renal handling of calcium and sodium in response to exogenous PTH was identical in patients with PsH (types I and II) and HP. Renal tubular reabsorption during a calcium infusion was normal in all patients with PsH. These results emphasise the importance of the modulatory effects due to associated biochemical abnormalities in PsH on the responses to exogenous PTH. They also confirm that renal handling of calcium and sodium is probably normal in treated PsH.

Comparison of low-dose intramuscular and intravenous salcatonin in the treatment of primary hyperparathyroidism.

The treatment of hypercalcaemia with low-dose salcatonin (100 U/d), administered either as a single intramuscular bolus or as a continuous intravenous infusion for five days, was examined in two groups of 10 patients with primary hyperparathyroidism, in a randomized open parallel study. Both the peak (0.31 +/- 0.035 mmol/L v 0.13 +/- 0.034 mmol/L) and overall (0.073 +/- 0.016 mmol/L v 0.018 +/- 0.016 mmol/L) hypocalcaemic responses were greater in the infusion group. The peak reduction in serum calcium occurred on day 2 of treatment after which there was a progressive attenuation of response. All the differences between the two methods of administration wer due to renal rather than bony effects of salcatonin. Possible causes of progressive resistance to treatment included reductions in sodium excretion and serum phosphate. It is concluded that low-dose salcatonin administered as a continuous infusion was more effective than the same dose given as a bolus. The kidney played a pivotal role both in the cause of the hypercalcaemia and in the response to treatment, including the rapid development of resistance which limits the use of salmon calcitonin in primary hyperparathyroidism to short-term reduction of serum calcium.

Pseudohypophosphataemia as a result of bilirubin interference.

During the routine use of a discrete analyser it was noted that, when the serum bilirubin concentration was greater than 50 mumol/L, there was interference with serum phosphate determination measured by the formation of unreduced phosphomolybdate using a bichromatic system of measurement. The degree of interference was assessed by comparison with a reduced phosphomolybdate method (molybdenum blue). The interference cannot be removed by changing the secondary wavelength or by the use of a sample blank. It is proportional to the serum bilirubin concentration, but is not significant when this is less than 50 mumol/L. The monochromatic non-reduced phosphomolybdate method compares well with the reduced method.

Determination of reference intervals for serum magnesium.

Using a discrete analyzer and a dye-binding method, we measured magnesium in 800 patients' samples received for routine analysis. By excluding data from samples for which the calcium and (or) alkaline phosphatase values were outside defined reference limits, we established a reference interval for magnesium. Because the data showed a gaussian distribution, we could use parametric analysis to establish age-related intervals for both males and females.

Guidelines (1988) for training in clinical laboratory management. International Federation of Clinical Chemistry (IFCC) Education Division and International Union of Pure and Applied Chemistry (IUPAC) Clinical Chemistry Division Commission on Teaching of Clinical Chemistry.

Trainees in laboratory medicine must develop skills in laboratory management. Guidelines are detailed for laboratory staff in training, directors responsible for staff development and professional bodies wishing to generate material appropriate to their needs. The syllabus delineates the knowledge base required and includes laboratory planning and organisation, control of operations, methodology and instrumentation, data management and statistics, financial management, clinical use of tests, communication, personnel management and training, and research and development. Methods for achievement of the skills required are suggested. A bibliography of IFCC publications and other material is provided to assist in training in laboratory management.

International Federation of Clinical Chemistry (IFCC), Education Division. Guidelines (1988) for training in clinical laboratory management.

Trainees in laboratory medicine must develop skills in laboratory management. Guidelines are detailed for laboratory staff in training, directors responsible for staff development and professional bodies wishing to generate material appropriate to their needs. The syllabus delineates the knowledge base required and includes laboratory planning and organisation, control of operations, methodology and instrumentation, data management and statistics, financial management, clinical use of tests, communication, personnel management and training, and research and development. Methods for achievement of the skills required are suggested. A bibliography of IFCC publications and other material is provided to assist in training in laboratory management.

International Federation of Clinical Chemistry Education Division and International Union of Pure and Applied Chemistry Clinical Chemistry Division Commission on Teaching of Clinical Chemistry. Guidelines (1988) for training in clinical laboratory management.

Trainees in laboratory medicine must develop skills in laboratory management. Guidelines are detailed for laboratory staff in training, directors responsible for staff development and professional bodies wishing to generate material appropriate to their needs. The syllabus delineates the knowledge base required and includes laboratory planning and organisation, control of operations, methodology and instrumentation, data management and statistics, financial management, clinical use of tests, communication, personnel management and training, and research and development. Methods for achievement of the skills required are suggested. A bibliography of IFCC publications and other material is provided to assist in training in laboratory management.

Guidelines (1988) for training in clinical laboratory management.

Trainees in laboratory medicine must develop skills in laboratory management. Guidelines are detailed for laboratory staff in training, directors responsible for staff development and professional bodies wishing to generate material appropriate to their needs. The syllabus delineates the knowledge base required and includes laboratory planning and organization, control of operations, methodology and instrumentation, data management and statistics, financial management, clinical use of tests, communication, personnel management and training and research and development. Methods for achievement of the skills required are suggested. A bibliography of IFCC publications and other material is provided to assist in training in laboratory management.