title: The incidence of gastrointestinal pathology and subsequent anemia in young men presenting with iron deficiency without anemia.
abstract: OBJECTIVE
  The etiology of iron deficiency (ID) without anemia in young men is unclear, and there are no evidence-based recommendations for the required gastrointestinal (GI) evaluation. The aims of this study were to examine the incidence of significant GI pathology and the development of anemia during the follow-up of young men presenting with ID, but without anemia.
  
  
  METHODS
  All young men (18-30 years) who served in the Israel Defense Forces during the years 2005-2013 and had at least a single laboratory test indicative of ID without anemia were followed until the diagnosis of significant GI pathology or discharge from military service.
  
  
  RESULTS
  The study population included 2061 young men (mean age 20.7±1.8). During follow-up of 3150 person years, significant GI pathologies were diagnosed in 39 patients: inflammatory bowel disease in 25 (1.2%), celiac disease in 8 (0.4%), and peptic disease in 4 (0.1%). No cases of GI-related cancer were diagnosed. ID anemia developed during follow-up in 203 (9.8%). Lower baseline hemoglobin levels, lower ferritin levels, and younger age at diagnosis were more common among those who developed anemia. The development of anemia was a predisposing factor for the diagnosis of GI pathology (risk ratio=3.60, 95% confidence interval 1.34-8.32, P=0.012).
  
  
  CONCLUSIONS
  Significant GI pathology is very uncommon in young men presenting with ID. Overt anemia developed in close to 10% of the study cohort. Therefore, we advise simple GI evaluation (celiac serology, C-reactive protein or fecal calprotectin, and urease breath test) as well as follow-up in this population.
authors.affiliation: aMedical Corps, Israel Defense Forces, Tel Hasomher bDepartment of Gastroenterology, Chaim Sheba Medical Center, Ramat Gan cSackler School of Medicine, Tel Aviv University, Tel Aviv, Israel.
authors.forename: Dan
authors.initials: D
authors.lastname: Carter
authors.forename: Eytan
authors.initials: E
authors.lastname: Bardan
authors.forename: Estela
authors.initials: E
authors.lastname: Derazne
authors.forename: Dorit
authors.initials: D
authors.lastname: Tzur
authors.forename: Benjamin
authors.initials: B
authors.lastname: Avidan
mesh_terms: D000293:Adolescent; D000328:Adult; D018798:Anemia, Iron-Deficiency / Q000097:blood / Q000175:diagnosis / Q000453:epidemiology*; D015415:Biomarkers / Q000097:blood; D018450:Disease Progression; D005767:Gastrointestinal Diseases / Q000175:diagnosis / Q000453:epidemiology* / Q000473:pathology; D041981:Gastrointestinal Tract / Q000473:pathology*; D006801:Humans; D015994:Incidence; D007501:Iron / Q000097:blood; D000090463:Iron Deficiencies; D019189:Iron Metabolism Disorders / Q000097:blood / Q000175:diagnosis / Q000453:epidemiology*; D007557:Israel / Q000453:epidemiology; D008297:Male; D016017:Odds Ratio; D011446:Prospective Studies; D012307:Risk Factors; D013997:Time Factors; D055815:Young Adult
chemical_list: D015415:Biomarkers; D007501:Iron