Rapidly reversible albumin and beta 2-microglobulin hyperexcretion in recent severe essential hypertension.

Seven young patients with newly diagnosed severe hypertension were studied for one week. The mean age was 34.9 years (range 28-44). The mean initial values +/- s.d. for systolic and diastolic pressures were 223 +/- 27 and 141 +/- 8 mmHg, respectively. Secondary hypertension was excluded by conventional methods and serum creatinine was normal. A pronounced but quite variably elevated albumin excretion 440 +/- 448 micrograms/min (mean +/- s.d.) and a moderately increased beta 2-microglobulin excretion 3.06 +/- 3.29 micrograms/min was noted before treatment. The abnormal albumin excretion with ensuing fall in blood pressure was rapidly and almost completely reversible in all but one patient during conventional treatment and the increased beta 2-microglobulin excretion was totally reversible in all but one patient. Both albumin and beta 2-microglobulin excretion rate were positively correlated to arterial pressures in all patients. Thus glomerular and to some extent tubular protein handling were both affected in untreated patients, but rapidly reversible during initial antihypertensive treatment. The data indicate that the beta 2-microglobulin hyperexcretion is secondary to enhanced filtration of plasma protein saturating the tubular reabsorption capacity, while the hyperexcretion of albumin is mainly due to the increased filtration pressure per se, though other factors may be partly responsible.