Reversible tubular lesion in pregnancy-induced hypertension detected by urinary β₂-microglobulin

Serum and urine β₂-microglobulin concentrations were measured in 17 primigravidas with mild pregnancy-induced hypertension and nine normotensive control patients matched for gestational age. Serum β₂-microglobulin and creatinine clearance values were not different between the two groups but urinary excretion of β₂-microglobulin was three times higher in the hypertensive patients. This difference disappeared within seven days of delivery. These results indicate that a reversible renal tubular lesion occurs in pregnancy-induced hypertension even in the absence of detectable proteinuria.