Chlorthalidone reduces calcium oxalate calculous recurrence but magnesium hydroxide does not.

We examined the effectiveness of chlorthalidone or magnesium hydroxide in the prevention of recurrent calcium oxalate kidney calculi. In a double-blind random allocation design daily dosages of 25 or 50 mg. chlorthalidone, 650 or 1,300 mg. magnesium hydroxide, or an identical placebo were administered. All groups showed significantly decreased calculous events compared to the pretreatment rates. During the trial 56.1 per cent fewer calculi than predicted developed in the placebo group (p less than 0.01), whereas the groups receiving low and high dosage magnesium hydroxide showed 73.9 and 62.3 per cent fewer calculi, respectively (p less than 0.001 and less than 0.01, respectively). Chlorthalidone treatment resulted in a 90.1 per cent decrease from predicted rates and both dosages yielded similar results. When the treatments were compared chlorthalidone was significantly better than the placebo or magnesium hydroxide (p less than 0.01). The large decreases in calculous events seen when placebo or ineffective therapy was given underscore the positive treatment bias that occurs when historical controls are used and they demonstrate the need for proper experimental design.

Metyrapone test with adrenocorticotrophic levels. Separating primary from secondary adrenal insufficiency.

Basal plasma adrenocorticotrophic hormone (ACTH) and cortisol concentrations as well as plasma ACTH and 11-deoxycortisol responses to the administration of a single dose of metyrapone were evaluated in 104 patients with intact pituitary-adrenal axis, in 20 patients with secondary adrenal insufficiency, and in seven patients with primary adrenal insufficiency. In patients with primary adrenal insufficiency, baseline ACTH levels were high. Following metyrapone administration, 11-deoxycortisol concentrations were low and ACTH levels did not change. In patients with secondary adrenal insufficiency, baseline plasma ACTH levels were normal, but neither 11-deoxycortisol nor ACTH levels increased in response to metyrapone. The metyrapone test is not only useful to screen for adrenal insufficiency, it is also useful to differentiate a primary from a secondary cause.

Infertility in patients with hyperprolactinemia from a pituitary adenoma. Effect of transsphenoidal pituitary adenectomy.

Four patients with infertility caused by a prolactin-secreting pituitary adenoma underwent transsphenoidal pituitary adenectomy. Preoperatively, in three patients prolactin level was elevated and gonadotropin levels were depressed. In one patient, prolactin level was elevated, and gonadotropin levels were normal, although no rise in gonadotropin levels was noted after clomiphene citrate therapy. In another patient growth hormone level was elevated. Pituitary function was otherwise normal in all patients. The patients underwent transsphenoidal pituitary adenectomy and postoperatively the first three showed normal prolactin and growth hormone levels. The fourth has not yet been reevaluated. Spontaneous pregnancy occurred in all four patients without manipulation shortly after surgery. We suggest that transsphenoidal pituitary adenectomy is a successful and low-risk approach to infertility secondary to prolactin-secreting pituitary adenomata.