title: Electrolyte disturbances in patients with hyponatremia.
abstract: OBJECTIVE
  Electrolyte abnormalities are frequently observed in patients with hyponatremia. The aim of this study was to determine the incidence of various electrolyte abnormalities encountered in hyponatremic patients admitted to an internal medicine clinic, as well as to investigate the possible pathogenetic mechanisms responsible for these abnormalities.
  
  
  METHODS
  We prospectively studied 204 adult patients who either on admission to our clinic or during their hospitalization were found to have hyponatremia.
  
  
  RESULTS
  Ninety-two patients (45.5%) had at least one additional electrolyte abnormality. Hypophosphatemia was the most frequent electrolyte disorder observed (35 patients, 17%). Hypokalemia was seen in 32 patients (15.8%), hypomagnesemia in 31 patients (15.2%) and hyperkalemia in 12 patients (5.9%). Moreover, 5 patients (2.5%) had hyperphosphatemia, 4 patients (1.9%) exhibited hypermagnesemia, 3 patients (1.4%) had hypercalcemia, and 6 patients (2.9%) had true hypocalcemia. There were no statistically significant differences regarding the incidence of these electrolyte abnormalities (as a whole) between the main subgroups of hyponatremic patients (diuretic-induced, syndrome of inappropriate antidiuretic hormone, hypovolemia-induced and edematous state-related). However, hypokalemia and hypomagnesemia were more frequently observed in patients with diuretic-induced hyponatremia, while hyperkalemia was more frequently seen in edematous state-related hyponatremia.
  
  
  CONCLUSIONS
  Additional electrolyte abnormalities are frequently encountered in patients with hyponatremia of any origin admitted to an internal medicine clinic.
authors.affiliation: Department of Internal Medicine, Medical School, University of Ioannina, Ioannina, Greece.
authors.forename: George
authors.initials: G
authors.lastname: Liamis
authors.forename: Zoi
authors.initials: Z
authors.lastname: Mitrogianni
authors.forename: Evangelos N
authors.initials: EN
authors.lastname: Liberopoulos
authors.forename: Vasilios
authors.initials: V
authors.lastname: Tsimihodimos
authors.forename: Moses
authors.initials: M
authors.lastname: Elisaf
mesh_terms: D000328:Adult; D004232:Diuretics / Q000009:adverse effects; D004487:Edema / Q000150:complications; D005260:Female; D006801:Humans; D006947:Hyperkalemia / Q000209:etiology / Q000503:physiopathology*; D007008:Hypokalemia / Q000209:etiology / Q000503:physiopathology*; D007010:Hyponatremia / Q000209:etiology / Q000503:physiopathology*; D017674:Hypophosphatemia / Q000209:etiology / Q000503:physiopathology*; D007177:Inappropriate ADH Syndrome / Q000150:complications; D015994:Incidence; D008274:Magnesium / Q000378:metabolism; D008297:Male; D011446:Prospective Studies; D012964:Sodium / Q000378:metabolism; D014882:Water-Electrolyte Balance / Q000502:physiology*
chemical_list: D004232:Diuretics; D012964:Sodium; D008274:Magnesium