Hydralazine-associated glomerulonephritis.

Nine patients (6 men, 3 women) with rapidly progressive glomerulonephritis developing during hydralazine therapy were seen. Early cessation of hydralazine treatment resulted in improvement in seven patients, while continued hydralazine treatment resulted in permanent renal insufficiency in two. The clinical symptoms of systemic illness associated with the hydralazine syndrome were absent in most patients. Antinuclear antibody test was positive in all, and six investigated patients had antibodies to histones. All patients had anemia, high ESR, and microscopic hematuria. Five of the nine patients were rapid drug acetylators. Renal biopsies from eight patients revealed a uniform histologic picture with segmental necrosis of glomeruli and extracapillary proliferation. Immunofluorescence investigation was positive in all and electron microscopy revealed deposits in the glomerular capillary walls in five of seven specimens. This renal disease may represent a late and monosymptomatic manifestation of the hydralazine syndrome.