Acute Renal Infarction: Clinical Characteristics and Prognostic Factors

Introduction: Acute renal infarction (ARI) is an uncommon disease, whose real incidence is probably higher than expected. It is associated with poor prognosis in a high percentage of cases.

Objectives: To describe the main clinical, biochemical and radiologic features and to determine which factors are associated with poor prognosis (death or permanent renal injury).

Materials And Methods: The following is a retrospective, observational, single-hospital-based study. All patients diagnosed with ARI by contrast-enhanced computed tomography (CT) over an 18-year period were included. Patients were classified according to the cardiac or non-cardiac origin of their disease. Clinical, biochemical and radiologic features were analysed, and multiple logistic regression model was used to determine factors associated with poor prognosis.

Results: A total of 62 patients were included, 30 of which had a cardiac origin. Other 32 patients with non-cardiac ARI were younger, had less comorbidity, and were less frequently treated with oral anticoagulants. CT scans estimated mean injury extension at 35%, with no differences observed between groups. A total of 38% of patients had an unfavourable outcome, and the main determinants were: Initial renal function (OR=0.949; IC 95% 0.918-0.980; p=0.002), and previous treatment with oral anticoagulants (OR=0.135; IC 95% 0.032-0.565; p=0.006).

Conclusions: ARI is a rare pathology with non-specific symptoms, and it is not associated with cardiological disease or arrhythmias in more than half of cases. A substantial proportion of patients have unfavourable outcomes, and the initial renal function is one of the main prognostic factors.