Objective: To assess the causes and frequency of kidney infarction associated with hypertension, and the blood pressure and renal function outcomes.
Methods: We analyzed the records of patients with kidney infarction documented by angiography and referred to a hypertension unit.
Results: Spontaneous kidney infarction was documented in 55 of 18,287 patients and was associated with renal artery disease in 41 cases. Twenty-five patients had a longstanding history of hypertension at referral, and 30 patients presented with acute hypertension. Patients with acute hypertension were more likely to report a history of lumbar pain and to develop malignant hypertension than patients with longstanding hypertension; they also had higher plasma renin concentrations. Data for long-term follow-up after referral were available for 36 patients, including 15 patients who underwent surgery or renal artery angioplasty. From referral to most recent follow-up, the blood pressure decreased from 176/111 to 143/89 mmHg in patients with longstanding hypertension, and from 183/111 to 127/80 mmHg in those with acute hypertension (P = 0.007/0.041 for between-group differences). Three patients with acute hypertension had normal blood pressure without treatment at follow-up. Patients with long-term follow-up displayed no change in the glomerular filtration rate.
Conclusion: Kidney infarction is a rare cause of hypertension, usually associated with renal artery lesions. In cases of kidney infarction with acute hypertension, the blood pressure outcome is favorable following intervention and/or medication, and hypertension may resolve spontaneously.