Renal infarction: An uncommon mimic presenting with flank pain

A 39-year-old woman arrived to the emergency department complaining of a co nstant, progressive, left flank pain, with no beneficial effect from spasmo lytic and nonsteroidal antiinflammatory drugs. Two years before, she suffer ed another episode of right flank pain and stranguria, but instrumental exa minations (ultrasonography, urography) remained negative. Besides a mild te nderness in the left flank, physical examination was normal. Blood chemistr y panel showed leukocytosis (17.2 x 10(3) mt, neutrophils 82.8%) and a slig ht increase of serum lactate dehydrogenase (LDH) (543 U/L versus 230 to 460 U/L). Urinanalysis showed a slight hemoglobinuria (0.5 mg/dL), and sedimen t contained some red cells and leukocytes. Diagnostic examinations (ultraso nography, computed tomography) showed a left renal nonhomogeneous space-occ upying lesion, orientative for renal malignancy, She was transferred to the urology department and operated, Both intraoperatory and histological diag nosis was ischemic infarction and, after exclusion of all possible underlyi ng causes, final diagnosis was idiopathic renal infarction. Diagnostic proc edures and literature reports are discussed. (Am J Emerg Med 2000;18:325-32 7, Copyright (C) 2000 by W.B. Saunders Company).