Changes in renal function during the development of hypertension and effects of antihypertensive treatment. A case report.

Renal function was serially investigated during the development of hypertension in a 12.8-year-old girl with chronic glomerulonephritis. Clearances of inulin (CIn) and para-aminohippuric acid (CPAH), filtration fraction, and sodium excretion were measured during hydropenia and isotonic saline volume expansion. Blood pressure was initially labile, but after a few years fixed hypertension developed, and antihypertensive treatment with propranolol was started. During the early stages of hypertension, the filtration fraction during hydropenia was reduced, but the natriuresis during volume expansion was normal. When the hypertension was fixed, glomerular filtration rate, CPAH, and filtration fraction were normal, but the natriuresis was exaggerated. Antihypertensive treatment only partially corrected the natriuresis.