A retrospective study of short- and long-term effects on renal function after acute renal infarction

Purpose: Acute renal infarction is often missed or diagnosed late due to its rarity and nonspecific clinical manifestations. This study analyzed the clinical and laboratory findings of patients diagnosed with renal infarction to determine whether it affects short-or long-term renal prognosis. Methods: We retrospectively reviewed the medical records of 100 patients diagnosed as acute renal infarction from January 1995 to September 2012 at Gyeongsang National University Hospital, Jinju, South Korea. Results: Acute kidney injury (AKI) occurred in 30 patients. Infarct size was positively correlated with the occurrence of AKI (p = 0.004). Compared with non-AKI patients, AKI occurrence was significantly correlated with degree of proteinuria (p < 0.001) and the presence of microscopic hematuria (p = 0.035). AKI patients had higher levels of aspartate transaminase (p < 0.001), alanine transaminase (p < 0.001), and lactated dehydrogenase (p = 0.027). AKI after acute renal infarction was more common in patients with chronic renal failure (CRF) (eGFR560 mL/min), compared with non-CRF patients, whose baseline eGFR was >60 mL/min (p = 0.003). Most patients recovered from AKI, except for seven patients (7%) who developed persistent renal impairment (chronic kidney disease progression) closely correlated with magnitude of infarct size (p = 0.015). Six AKI patients died due to combined comorbidity. Conclusions: AKI is often associated with acute renal infarction. Although most AKI recovers spontaneously, renal impairment following acute renal infarction can persist. Thus, early diagnosis and intervention are needed to preserve renal function.