INBORN ENZYMATIC DEFECT AS THE PROBABLE CAUSE OF THE FORMATION OF RENAL STONES CONSISTING OF URIC ACID

In four persons of one family the existence of an enzymatic defect, presumably consisting of a deficiency of glutaminase in the cells of the renal tubules, is postulated, and is implied by a reduced elimination of ammonia in the urine, by a relatively low urinary pH, and by its increased titratable acidity. The most characteristic clinical symptom is irritation of the distal part of the urinary tract, connected with numerous crystals of uric acid appearing in the urinary sediment. The elimination of uric acid is normal, or even reduced, and the level of uric acid in the blood serum is also within normal limits. After the administration of glutaminic acid elimination of ammonia is further decreased and the quantity of uric acid crystals is increased. Loading with glutaminic acid may also cause an attack of renal pain in the individual suffering from this defect but the administration of ammonium chloride does not cause any increase in ammonia production. It seems probable that the enzymatic defect is connected with the presence of antigen B in the erythrocytes and that it is inherited as a dominant autosomal feature. A suitable diet to make the urine alkaline allows kidneys to function efficiently in individuals suffering from this defect.

ETIOLOGICAL FACTORS IN THIAZIDE-INDUCED OR AGGRAVATED DIABETES MELLITUS

Nine patients with diabetes mellitus and three normal controls were treated for one week with hydrochlorothiazide (150 mg. per day), and certain effects on carbohydrate metabolism were observed. Evidence presented in this study confirms the thiazide-induced carbohydrate intolerance. Tests of insulin reserve (serum ILA response to glucose), response to insulin, insulin binding, urinary steroid excretion, serum potassium, serum nonesterified fatty acids, and serum amylase failed to reveal any abnormality related to the carbohydrate intolerance. There was reduction of the whole blood glutathione levels in six of seven subjects. DIABETES 14:132–36, March 1965.

TREATMENT OF CONGESTIVE HEART FAILURE WITH TRIAMTERENE

Triamterene, a newer oral diuretic, was administered to nine hospitalized patients with congestive heart failure for an average of 15 days, and to 22 ambulatory patients for a period of three to 11 months. The daily dosage of triamterene ranged from 50 to 250 mg., but usually 100-200 mg. was administered daily in two divided doses, with or without the addition of 50 mg. of hydrochlorothiazide daily.Triamterene is a safe and effective diuretic at doses of 100-200 mg. daily and no drug tolerance develops with long-term therapy. However, when used alone, it is not as effective as hydrochlorothiazide, but in combination with the latter drug the resultant diuresis is unsurpassed by any other oral diuretic therapy that we have used to date.Triamterene itself does not produce kaliuresis and it blocks thiazide-induced kaliuresis. Serum uric acid levels may rise slightly, but no clinical gout was seen in this study.