Background: Renal vein thrombosis, long recognized as a classical complication of acute pyelonephritis, has become exceptional since the advent of antibiotics.
Case report: An 85-year-old woman was hospitalized for acute Escherichia coli nephritis. Computed tomography with contrast agent injection was performed due to clinical improvement after an 8-day course of antibiotics and demonstrated purulent urine collection on an obstructive calicial stone as well as homolateral thrombosis of the renal vein. Duplex Doppler confirmed the diagnosis. Pulmonary embolism was evidenced by pulmonary scintigraphy. The clinical course was satisfactory after urine drainage and efficacious antibiotics.
Conclusion: Renal vein thrombosis remains a severe though uncommon complication of acute pyelonephritis. Computed tomography with iodine, contrast agent or duplex Doppler allows noninvasive diagnosis.