Evaluation of lupus nephritis during pregnancy by renal biopsy.

Patients with lupus nephritis frequently exhibit increasing proteinuria, hypertension and deterioration of renal function due to either active lupus nephritis, chronic lupus nephritis and/or superimposed preeclampsia during pregnancy. Percutaneous renal biopsies were therefore performed in 3 women with systemic lupus erythematosus during pregnancy and immediately postpartum in a fourth woman to evaluate their renal disease during pregnancy. Mean serum creatinine at renal biopsy was 2.9 mg/dl, with a mean creatinine clearance of 66 ml/min and protein excretion of 5.3 g/day. All patients had grade IV lupus nephritis and received pulse methylprednisolone immediately; 3 received cyclophosphamide. All 3 patients with crescent formation developed endstage renal disease within 3 years. The fourth patient has normal renal function 3 years after biopsy. Percutaneous renal biopsies during pregnancy in women with lupus nephritis provide an accurate histopathologic diagnosis and are important in providing appropriate therapy, counseling and prognosis.