title: Mineral content of infant formula after treatment with sodium polystyrene sulfonate or calcium polystyrene sulfonate.
abstract: Options for the management of infants with hyperkalemia secondary to renal insufficiency are limited for infants not maintained on dialysis. Precipitation of potassium (K+) from infant formula with sodium polystyrene sulfonate (KX) prior to feeding has been reported. However, its effect on calcium (Ca2+) and sodium (Na+) has not been quantitatively defined. The purpose of this study was to examine the effects of two K+ exchange resins: KX and calcium polystyrene sulfonate (RC) on Na+, K+, and Ca2+. Infant formula powder (Similac PM 60/40, Ross Laboratories, Columbus, OH, USA) was prepared with deionized water (DW) and KX or RC (1 g/mEq of K+) was added. The formula was decanted after 50 minutes and Na+, K+, and Ca2+ were assayed in the supernatant. Na+ and K+ were also assayed in ready-to-feed PM 60/40 (RTF). KX decreased the K+ concentration by 4.5 fold (P < 0.001) and increased the Na+ content by 3.8 fold (P < 0.001). In RC there was a 1.6-fold increase in Ca2+ content (P < 0.001), and a 13% decrease in K+ concentrations (P < 0.05). Preparation of the formula with DW reduced the K+ concentration by 30% compared to ready-to-feed formula (P < 0.001). We conclude that, although KX significantly reduces the K+ content of formulas, DW may be a more practical and convenient method of preparing formula for the hyperkalemic infant.
authors.affiliation: Department of Pediatrics, Children's Hospital of Michigan, Wayne State University, Detroit, USA.
authors.forename: N
authors.initials: N
authors.lastname: Fassinger
authors.forename: S
authors.initials: S
authors.lastname: Dabbagh
authors.forename: S
authors.initials: S
authors.lastname: Mukhopadhyay
authors.forename: D Y
authors.initials: DY
authors.lastname: Lee
mesh_terms: D002118:Calcium / Q000032:analysis; D002411:Cation Exchange Resins; D011232:Chemical Precipitation; D006801:Humans; D006947:Hyperkalemia / Q000209:etiology / Q000628:therapy; D007223:Infant; D007225:Infant Food / Q000032:analysis*; D008903:Minerals / Q000032:analysis*; D011137:Polystyrenes; D011188:Potassium / Q000032:analysis; D017419:Potassium, Dietary / Q000008:administration & dosage; D051437:Renal Insufficiency / Q000150:complications; D012964:Sodium / Q000032:analysis; D015032:Zinc / Q000032:analysis
chemical_list: D002411:Cation Exchange Resins; D008903:Minerals; D011137:Polystyrenes; D017419:Potassium, Dietary; C003321:polystyrene sulfonic acid; D012964:Sodium; D015032:Zinc; D011188:Potassium; D002118:Calcium