title: Acute thiamine deficiency and refeeding syndrome: Similar findings but different pathogenesis.
abstract: OBJECTIVE
  Refeeding syndrome can occur in several contexts of relative malnutrition in which an overaggressive nutritional support is started. The consequences are life threatening with multiorgan impairment, and severe electrolyte imbalances. During refeeding, glucose-involved insulin secretion causes abrupt reverse of lipolysis and a switch from catabolism to anabolism. This creates a sudden cellular demand for electrolytes (phosphate, potassium, and magnesium) necessary for synthesis of adenosine triphosphate, glucose transport, and other synthesis reactions, resulting in decreased serum levels. Laboratory findings and multiorgan impairment similar to refeeding syndrome also are observed in acute thiamine deficiency. The aim of this study was to determine whether thiamine deficiency was responsible for the electrolyte imbalance caused by tubular electrolyte losses.
  
  
  METHODS
  We describe two patients with leukemia who developed acute thiamine deficiency with an electrolyte pattern suggestive of refeeding syndrome, severe lactic acidosis, and evidence of proximal renal tubular dysfunction.
  
  
  RESULTS
  A single thiamine administration led to rapid resolution of the tubular dysfunction and normalization of acidosis and electrolyte imbalance. This demonstrated that thiamine deficiency was responsible for the electrolyte imbalance, caused by tubular electrolyte losses.
  
  
  CONCLUSIONS
  Our study indicates that, despite sharing many laboratory similarities, refeeding syndrome and acute thiamine deficiency should be viewed as separate entities in which the electrolyte abnormalities reported in cases of refeeding syndrome with thiamine deficiency and refractory lactic acidosis may be due to renal tubular losses instead of a shifting from extracellular to intracellular compartments. In oncologic and malnourished patients, individuals at particular risk for developing refeeding syndrome, in the presence of these biochemical abnormalities, acute thiamine deficiency should be suspected and treated because it promptly responds to thiamine administration.
authors.affiliation: Division of Metabolism and Research Unit of Metabolic Biochemistry, Department of Pediatric Medicine, Bambino Gesù Children's Hospital and Research Institute, Rome, Italy. Electronic address: arianna.maiorana@opbg.net.
authors.forename: Arianna
authors.initials: A
authors.lastname: Maiorana
authors.affiliation: Division of Nephrology and Dialysis, Department of Nephrology & Urology, Bambino Gesù Children's Hospital and Research Institute, Rome, Italy.
authors.forename: Gianluca
authors.initials: G
authors.lastname: Vergine
authors.affiliation: Division of Hematology, Department of Hematology and Oncology, Bambino Gesù Children's Hospital and Research Institute, Rome, Italy.
authors.forename: Valentina
authors.initials: V
authors.lastname: Coletti
authors.affiliation: Division of Hematology, Department of Hematology and Oncology, Bambino Gesù Children's Hospital and Research Institute, Rome, Italy.
authors.forename: Matteo
authors.initials: M
authors.lastname: Luciani
authors.affiliation: Division of Metabolism and Research Unit of Metabolic Biochemistry, Department of Pediatric Medicine, Bambino Gesù Children's Hospital and Research Institute, Rome, Italy.
authors.forename: Cristiano
authors.initials: C
authors.lastname: Rizzo
authors.affiliation: Division of Nephrology and Dialysis, Department of Nephrology & Urology, Bambino Gesù Children's Hospital and Research Institute, Rome, Italy.
authors.forename: Francesco
authors.initials: F
authors.lastname: Emma
authors.affiliation: Division of Metabolism and Research Unit of Metabolic Biochemistry, Department of Pediatric Medicine, Bambino Gesù Children's Hospital and Research Institute, Rome, Italy.
authors.forename: Carlo
authors.initials: C
authors.lastname: Dionisi-Vici
mesh_terms: D000140:Acidosis, Lactic / Q000188:drug therapy* / Q000209:etiology; D002648:Child; D004573:Electrolytes / Q000378:metabolism*; D005260:Female; D006801:Humans; D007223:Infant; D007684:Kidney Tubules / Q000378:metabolism / Q000503:physiopathology*; D007938:Leukemia / Q000628:therapy; D008297:Male; D018529:Nutritional Support / Q000009:adverse effects; D055677:Refeeding Syndrome / Q000150:complications / Q000175:diagnosis*; D013831:Thiamine / Q000627:therapeutic use*; D013832:Thiamine Deficiency / Q000150:complications / Q000175:diagnosis* / Q000188:drug therapy; D014883:Water-Electrolyte Imbalance / Q000188:drug therapy* / Q000209:etiology
chemical_list: D004573:Electrolytes; D013831:Thiamine
keywords: Hypophosphatemia; Lactic acidosis; Methotrexate; Refeeding syndrome; Renal tubular dysfunction; Thiamine