Is elevated plasma renin activity of prognostic importance in progressive systemic sclerosis?

The pathologic lesions of the kidney in scleroderma in many respects resemble those of malignant hypertension, perhaps even in the absence of comparable blood pressure elevation. Because the malignant vascular changes have been related to hyperreninemia, we measured plasma renin activity in 23 patients with scleroderma with or without hypertension and/or renal failure. We found that high renin levels in most cases shortly preceded or coincided with a phase of sudden deterioration of the disease, characterized by a rapidly progressive renal failure. The outcome of this phase was invariably fatal, except for two patients in whom bilateral nephrectomy successfully arrested the rapid downhill course. These findings suggest that an unexplained increase in circulating renin levels in an otherwise stable patient with scleroderma may be taken as a possible marker of imminent deterioration requiring close monitoring and immediate therapeutic intervention.