title: Liver enzyme levels and hepatic iron content in Fatty liver: a noninvasive assessment in general population by T2* mapping.
abstract: OBJECTIVE
  Existing evidence suggests potential contribution of iron in pathogenesis of nonalcoholic fatty liver disease (NAFLD). We aimed to investigate whether hepatic iron content correlates with liver enzyme levels in NAFLD using a noninvasive magnetic resonance imaging (MRI) technique.
  
  
  METHODS
  Subjects from Golestan Cohort Study were randomly selected. Diagnosis of NAFLD was made by combination of ultrasound and MRI. Subjects with NAFLD were divided into two groups with high (H-NAFLD) and low (L-NAFLD) enzyme level according to 95th percentile of alanine aminotransferase (ALT) value in normal population. Quantitative T2* maps of entire cross-sectional area of liver were calculated on pixel-by-pixel basis using a semiautomated software.
  
  
  RESULTS
  A total of 207 subjects were enrolled. Mean T2* values were significantly lower in NAFLD group than controls (P < .001) indicating higher iron content. Male subjects with H-NAFLD had statistically lower T2* values than those with L-NAFLD in multivariate analysis (odds ratio, 0.74; 95% confidence interval [CI], 0.58-0.95), whereas this was not observed in women. Unlike women, there was significant negative correlation between ALT levels and T2* values in men with H-NAFLD (r = -0.66, P = .01). Every 1-millisecond decrement in T2* value was associated with 6.37 IU/L increase in ALT level (95% CI, 1.8-10.9, P = .01) in men with H-NAFLD.
  
  
  CONCLUSIONS
  Higher hepatic iron in men with H-NAFLD, estimated by T2* mapping, may support the role of iron in possible progression of simple steatosis to nonalcoholic steatohepatitis. Lack of such correlation in women could be attributed to relatively lower iron storage or other mechanisms rather than iron.
authors.affiliation: Department of Radiology, Shariati Hospital, Tehran University of Medical Sciences, Tehran, Iran; Digestive Tract Image Processing Research Group, Digestive Diseases Research Institute, Tehran University of Medical Sciences, Tehran, Iran.
authors.forename: Amir Reza
authors.initials: AR
authors.lastname: Radmard
authors.affiliation: Liver and Pancreatobiliary Diseases Research Center, Digestive Diseases Research Institute, Tehran University of Medical Sciences, Shariati Hospital, North Kargar Avenue, Tehran 14117-13135, Iran.
authors.forename: Hossein
authors.initials: H
authors.lastname: Poustchi
authors.affiliation: Digestive Tract Image Processing Research Group, Digestive Diseases Research Institute, Tehran University of Medical Sciences, Tehran, Iran; Department of Electrical Engineering, Central Tehran Branch, Islamic Azad University, Tehran, Iran.
authors.forename: Mehrdad
authors.initials: M
authors.lastname: Dadgostar
authors.affiliation: Digestive Tract Image Processing Research Group, Digestive Diseases Research Institute, Tehran University of Medical Sciences, Tehran, Iran; Neuroscience Department, School of Advanced Technologies in Medicine, Tehran University of Medical Sciences, Tehran, Iran.
authors.forename: Ali
authors.initials: A
authors.lastname: Yoonessi
authors.affiliation: Department of Radiology, Shariati Hospital, Tehran University of Medical Sciences, Tehran, Iran.
authors.forename: Soheil
authors.initials: S
authors.lastname: Kooraki
authors.affiliation: Liver and Pancreatobiliary Diseases Research Center, Digestive Diseases Research Institute, Tehran University of Medical Sciences, Shariati Hospital, North Kargar Avenue, Tehran 14117-13135, Iran.
authors.forename: Elham
authors.initials: E
authors.lastname: Jafari
authors.affiliation: Department of Radiology, Shariati Hospital, Tehran University of Medical Sciences, Tehran, Iran.
authors.forename: Amir Pejman
authors.initials: AP
authors.lastname: Hashemi Taheri
authors.affiliation: Liver and Pancreatobiliary Diseases Research Center, Digestive Diseases Research Institute, Tehran University of Medical Sciences, Shariati Hospital, North Kargar Avenue, Tehran 14117-13135, Iran.
authors.forename: Reza
authors.initials: R
authors.lastname: Malekzadeh
authors.affiliation: Liver and Pancreatobiliary Diseases Research Center, Digestive Diseases Research Institute, Tehran University of Medical Sciences, Shariati Hospital, North Kargar Avenue, Tehran 14117-13135, Iran. Electronic address: merat@tums.ac.ir.
authors.forename: Shahin
authors.initials: S
authors.lastname: Merat
mesh_terms: D000368:Aged; D000410:Alanine Transaminase / Q000378:metabolism*; D015331:Cohort Studies; D003430:Cross-Sectional Studies; D005260:Female; D006801:Humans; D007501:Iron / Q000378:metabolism*; D008099:Liver / Q000201:enzymology / Q000378:metabolism*; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D065626:Non-alcoholic Fatty Liver Disease / Q000201:enzymology / Q000378:metabolism*; D015588:Observer Variation; D016017:Odds Ratio; D012307:Risk Factors; D012720:Severity of Illness Index; D012737:Sex Factors
chemical_list: D007501:Iron; D000410:Alanine Transaminase
keywords: Hepatic iron; T2* mapping; nonalcoholic fatty liver disease; serum transaminase