Lymphocytic sodium and potassium pump function in Bartter's syndrome.

Bartter's syndrome is characterized by chronic hypokalaemia, activation of the renin-angiotensin system and normal blood pressure. To investigate whether a generalized disturbance of sodium-potassium pump function might be of pathogenetic importance, lymphocytic sodium-potassium homeostasis was examined in 5 patients suffering from Bartter's syndrome. Two of the patients were treated with potassium chloride supplementation, the others were without medical treatment when studied. All were severely hypokalemic (serum potassium 2.8 +/- 0.24 mmol/l, mean +/- SEM). Lymphocyte sodium and potassium concentration (14.4 +/- 0.37 and 94.4 +/- 7.7 mmol/l, respectively), ouabain sensitive 22Na-efflux rate constant (2.68 +/- 0.25 h), and absolute ouabain sensitive efflux rate (38.16 +/- 4.2 mmol l-1 h) did not differ from matched controls. Ouabain binding capacity was 126 900 +/- 23 500 sites/cell in patients vs 50 400 +/- 17 900 in controls (p less than 0.05). In conclusion, patients with Bartter's syndrome may have an intrinsic abnormal pump function, characterized by an increased pump density and a low cation turn-over rate per pump unit.

Hypercalcemia due to primary hyperparathyroidism or malignant disease. Evaluated by means of biochemical tests and the steroid suppression test.

The cortisone suppression test and some biochemical tests were evaluated in 13 patients with hypercalcemia due to primary hyperparathyroidism (PHP) and in 10 with hypercalcemia due to a malignant disease. The biochemical tests revealed that serum chloride was significantly raised in patients with PHP compared to patients with malignant diseases, whereas no differences were observed with regard to the serum values of corrected calcium, serum phosphate, chloride/phosphate ratio, HCO3-. Although serum values of parathyroid hormone were higher in patients with PHP, a consider-able overlap was observed between values in the two patient groups. Corrected serum calcium values were significantly suppressed during cortisone administration in patients with malignant disease compared to patients wit PHP, whereas prednisolone had no suppressive effect. The positive predictive value of the test was 80.0% and the negative predictive value 66.7%. We conclude that there is still no entirely reliable method to distinguish between hypercalcemia due to PHP or malignant disease.

Propranolol in the treatment of thyrotoxicosis. A randomized double-blind study.

Twenty-five patients with newly diagnosed thyrotoxicosis participated in a double-blind study of the added effect of propranolol during tiamazol treatment. During the trial, the effect of treatment was ascertained by estimation at regular intervals of the clinical score (Crooks-Wayne index), free thyroxine index, serum triiodothyronine, serum reverse triiodothyronine, serum thyroglobulin and serum thyroglobulin antibodies. Both groups became euthyroid within two weeks. No statistically significant difference in the values for the clinical score or for any of the laboratory parameters measured was found between propranolol- and the placebo-treated patients. It is concluded that propranolol has no beneficial effect on tiamazol-treated hyperthyroid patients.

Pseudohypoparathyroidism. A 25-year delay in diagnosis.

The diagnosis of pseudohypoparathyroidism is often not made until many years after the onset of symptoms and signs characteristic of the disease. A case history presented here illustrates this and stresses the importance of determining the calcium concentration in plasma in all patients with attacks of sensory and motor phenomena.