Article Text

Download PDFPDF
Are blood ammonia concentrations dependent on γ-glutamyl-transferase levels in plasma?
  1. Dominika Szo˝ke,
  2. Sarah Birindelli,
  3. Sara Pasqualetti,
  4. Alberto Dolci,
  5. Mauro Panteghini
  1. Clinical Pathology Unit, ‘Luigi Sacco’ University Hospital, Milan, Italy
  1. Correspondence to Dr Dominika Szo˝ke, UOC Patologia Clinica, Azienda Ospedaliera ‘Luigi Sacco’, Via GB Grassi 74, Milano 20157, Italy; szoke.dominika{at}

Statistics from

Request Permissions

If you wish to reuse any or all of this article please use the link below which will take you to the Copyright Clearance Center’s RightsLink service. You will be able to get a quick price and instant permission to reuse the content in many different ways.

To the Editor,

We read with interest the letter by Schuff-Werner and Steiner1 that commented a recently published article dealing with the evaluation of the short- and long-term storage stability of plasma ammonia.2 We were particularly impressed by the authors’ claim that blood ammonia values may significantly depend on the activity of γ-glutamyl-transferase (GGT) in plasma. They support this conclusion by reporting experimental results obtained in two samples with low and increased GGT catalytic concentrations stored up to 6 h either at room temperature or at 4°C.1

Several, mostly preanalytical, factors, like haemolysis and poor specimen quality, skin contamination and delayed analysis in general, may cause artificial increase of blood ammonia.3 ,4 If the systematic detection of haemolysis through the automatic photometric measurement of haemolysis index (HI) is now relatively common, it is more difficult for laboratories to keep the time short between blood drawing and analysis. To prevent an artificial increase of ammoniaemia caused by the metabolism of red blood cells due …

View Full Text


  • Contributors All authors contributed to the conception of the work, acquisition of the material, analysis and interpretation of data, and drafting of the manuscript.

  • Competing interests None declared.

  • Provenance and peer review Not commissioned; externally peer reviewed.