title: Plasma endotoxin core antibody concentration and linear growth are unrelated in rural Malawian children aged 2-5 years.
abstract: BACKGROUND
  Environmental enteropathy is subclinical inflammation of the upper gastrointestinal tract associated with reduced linear growth in developing countries. Usually investigators have used biopsy or a dual sugar absorption test to assess environmental enteropathy. Such tests are time and resource intensive, restricting their utility as screening methods. Serum endotoxin core antibody (EndoCab) concentration is a potential indicator of intestinal inflammation and integrity, and thus may be useful to predict environmental enteropathy. We analyzed the association of serum EndoCab levels versus linear growth and lactulose-mannitol assay results in 2-5 year old rural Malawian children.
  
  
  METHODS
  This was an observational study of 388 rural, asymptomatic Malawian children who had anthropometric measurements taken at least every 3 months since birth. In June and July 2011, dual sugar permeability tests were performed and serum samples were drawn for EndoCab assays. Pearson correlation, Student's t test and multivariable linear regression were used to compare ln EndoCab concentrations with height-for-age z scores (HAZ) at time of sampling and 3 months later. Identical analysis was also performed for ln EndoCab versus measurements from dual sugar permeability testing performed in conjunction with serum sampling. In a subgroup of children with anthropometric data in the months prior to serum sampling, Pearson correlation was used to estimate the relationship between ln EndoCab and recent linear growth.
  
  
  RESULTS
  Ln EndoCab concentrations were not correlated with HAZ at time of measurement (B = -0.078, P = 0.14) nor change in HAZ over the subsequent 3 months HAZ (B = -0.018, P = 0.27). EndoCab concentration was not associated with %lactulose excretion (B < 0.001, P = 0.98) nor the lactulose:mannitol ratio (B = 0.021, P = 0.62). Subgroup analysis also did not reveal any significant association between EndoCab and recent growth.
  
  
  CONCLUSIONS
  EndoCab titers were not correlated with measurements of growth or intestinal permeability in rural pre-school aged Malawian children.
authors.affiliation: Department of Pediatrics, Washington University, St. Louis, MO, 63110, USA. benzonin@wusm.wustl.edu.
authors.forename: Nicole
authors.initials: N
authors.lastname: Benzoni
authors.affiliation: School of Public Health, Johns Hopkins University, Baltimore, MD, USA. poonumkorpe@gmail.com.
authors.forename: Poonum
authors.initials: P
authors.lastname: Korpe
authors.affiliation: Department of Community Health, College of Medicine, University of Malawi, Blantyre, Malawi. cthakwalakwa@gmail.com.
authors.forename: Chrissie
authors.initials: C
authors.lastname: Thakwalakwa
authors.affiliation: Department of Community Health, College of Medicine, University of Malawi, Blantyre, Malawi. ken.maleta@gmail.com.
authors.forename: Ken
authors.initials: K
authors.lastname: Maleta
authors.affiliation: College of Physicians and Surgeons, Columbia University, New York, NY, USA. kbstephe@gmail.com.
authors.forename: Kevin
authors.initials: K
authors.lastname: Stephenson
authors.affiliation: School of Medicine, University of California, San Diego, San Diego, CA, USA. mmanary@gmail.com.
authors.forename: Micah
authors.initials: M
authors.lastname: Manary
authors.affiliation: Department of Pediatrics, Washington University, St. Louis, MO, 63110, USA. manary@kids.wustl.edu.|Department of Pediatrics, St. Louis Children's Hospital, One Children's Place, St. Louis, MO, 63110, USA. manary@kids.wustl.edu.
authors.forename: Mark
authors.initials: M
authors.lastname: Manary
mesh_terms: D000886:Anthropometry; D000906:Antibodies / Q000097:blood*; D002675:Child, Preschool; D004731:Endotoxins / Q000097:blood* / Q000276:immunology; D005260:Female; D006130:Growth Disorders / Q000097:blood / Q000150:complications / Q000175:diagnosis* / Q000382:microbiology; D006801:Humans; D007410:Intestinal Diseases / Q000097:blood / Q000150:complications / Q000175:diagnosis* / Q000382:microbiology; D007413:Intestinal Mucosa / Q000276:immunology / Q000382:microbiology; D007792:Lactulose / Q000378:metabolism; D008295:Malawi; D008297:Male; D008353:Mannitol / Q000378:metabolism; D012424:Rural Population
chemical_list: D000906:Antibodies; D004731:Endotoxins; C042058:core endotoxin; D008353:Mannitol; D007792:Lactulose