title: Newly-identified symptoms of left renal vein entrapment syndrome mimicking orthostatic disturbance.
abstract: BACKGROUND
  In addition to the urinary abnormalities, symptoms of left renal vein entrapment between the aorta and superior mesenteric artery (left renal vein entrapment syndrome, LRVES) may include abdominal and flank pain as well as chronic fatigue. We investigated various LRVES symptoms in this study.
  
  
  METHODS
  In 53 pediatric LRVES patients treated at our department, 22 had a score of 5 points or higher on orthostasis. Initial evaluation of LRVES by abdominal ultrasonography showed a stenotic-to-prestenotic vein diameter ratio of 0.2 or less. Definitive diagnosis was made by computed tomography and magnetic resonance angiography. Cortisol, catecholamine (CA), and brain natriuretic peptide (BNP) were also measured.
  
  
  RESULTS
  The frequency of LRVES was 2.5 times higher in girls than in boys. Low or very low body mass indexes were seen in both sexes. The most common initial finding was urine abnormalities, followed by dizziness and malaise. In 6 patients, orthostasis precluded school attendance. Ten patients had orthostasis scores above 12. Patients unable to attend school had either low levels of plasma or urinary cortisol. Midodrine significantly decreased orthostasis scores. Some patients required treatment with fludrocortisone. Plasma CA, renin, and BNP levels were all normal.
  
  
  CONCLUSIONS
  Locally excessive venous pressure may cause reversible adrenal dysfunction with transitory Addisonian symptoms. Children with cryptogenic malaise or severe orthostasis should be evaluated for LRVES.
authors.affiliation: Department of Pediatrics, Kinki University School of Medicine, Osaka, Japan.
authors.forename: Machiko
authors.initials: M
authors.lastname: Koshimichi
authors.forename: Keisuke
authors.initials: K
authors.lastname: Sugimoto
authors.forename: Hidehiko
authors.initials: H
authors.lastname: Yanagida
authors.forename: Shinsuke
authors.initials: S
authors.lastname: Fujita
authors.forename: Tomoki
authors.initials: T
authors.lastname: Miyazawa
authors.forename: Naoki
authors.initials: N
authors.lastname: Sakata
authors.forename: Mitsuru
authors.initials: M
authors.lastname: Okada
authors.forename: Tsukasa
authors.initials: T
authors.lastname: Takemura
mesh_terms: D000293:Adolescent; D002648:Child; D003937:Diagnosis, Differential; D005260:Female; D006801:Humans; D008297:Male; D011187:Posture; D059228:Renal Nutcracker Syndrome / Q000175:diagnosis*; D055815:Young Adult