title: Influence of the amount of co-infused amino acids on post-therapeutic potassium levels in peptide receptor radionuclide therapy.
abstract: BACKGROUND
  Peptide receptor radionuclide therapy (PRRT) is routinely used for advanced or metastasized neuroendocrine tumours (NET). To prevent nephrotoxicity, positively charged amino acids (AA) are co-infused. The aim of this study was to correlate the risk for therapy-related hyperkalaemia with the total amount of AA infused.
  
  
  METHODS
  Twenty-two patients undergoing PRRT with standard activities of (177)Lu-DOTATATE/-TOC were monitored during two following treatment cycles with co-infusion of 75 and 50 g of AA (l-arginine and l-lysine), respectively. Mean serum levels of potassium and other parameters (glomerular filtration rate [GFR], creatinine, blood urea nitrogen [BUN], phosphate, chloride, lactate dehydrogenase) prior to, 4 h and 24 h after AA infusion were compared.
  
  
  RESULTS
  Self-limiting hyperkalaemia (>5.0 mmol/l) resolving after 24 h occurred in 91% (20/22) of patients in both protocols. Potassium levels, BUN, creatinine, GFR, phosphate, chloride and LDH showed a similar range at 4 h after co-infusion of 75 or 50 g of AA, respectively (p?>?0.05). Only GFR and creatinine levels at 24 h varied significantly between the two co-infusion protocols (p?<?0.05).
  
  
  CONCLUSIONS
  Hyperkalaemia is a frequent side effect of AA infusion in PRRT. Varying the dose of co-infused amino acids did not impact on the incidence and severity of hyperkalaemia.
authors.affiliation: Department of Nuclear Medicine, University Hospital Würzburg, Oberdürrbacher Str. 6, Würzburg 97080, Germany.
authors.forename: Constantin
authors.initials: C
authors.lastname: Lapa
authors.affiliation: Department of Nuclear Medicine, University Hospital Würzburg, Oberdürrbacher Str. 6, Würzburg 97080, Germany.
authors.forename: Rudolf A
authors.initials: RA
authors.lastname: Werner
authors.affiliation: Department of Nuclear Medicine, University Hospital Würzburg, Oberdürrbacher Str. 6, Würzburg 97080, Germany.
authors.forename: Christina
authors.initials: C
authors.lastname: Bluemel
authors.affiliation: Department of Nuclear Medicine, University Hospital Würzburg, Oberdürrbacher Str. 6, Würzburg 97080, Germany.
authors.forename: Katharina
authors.initials: K
authors.lastname: Lückerath
authors.affiliation: Department of Nuclear Medicine, University Hospital Würzburg, Oberdürrbacher Str. 6, Würzburg 97080, Germany.
authors.forename: Andreas
authors.initials: A
authors.lastname: Schirbel
authors.affiliation: Institute of Clinical Chemistry, University Hospital Würzburg, Oberdürrbacher Str. 6, Würzburg 97080, Germany.
authors.forename: Alexander
authors.initials: A
authors.lastname: Strate
authors.affiliation: Department of Nuclear Medicine, University Hospital Würzburg, Oberdürrbacher Str. 6, Würzburg 97080, Germany.
authors.forename: Andreas K
authors.initials: AK
authors.lastname: Buck
authors.affiliation: Department of Nuclear Medicine, University Hospital Würzburg, Oberdürrbacher Str. 6, Würzburg 97080, Germany.
authors.forename: Ken
authors.initials: K
authors.lastname: Herrmann
keywords: Arginine; Hyperkalaemia; Lysine; NET; PRRT