title: Electrolyte abnormalities in cystic fibrosis: systematic review of the literature.
abstract: BACKGROUND
  Cystic fibrosis per se can sometimes lead to hyponatremia, hypokalemia, hypochloremia or hyperbicarbonatemia. This tendency was first documented 60 years ago and has subsequently been confirmed in single case reports or small case series, most of which were retrospective. However, this issue has not been addressed analytically. We have therefore systematically reviewed and analyzed the available literature on this subject.
  
  
  METHODS
  This was a systematic review of the literature.
  
  
  RESULTS
  The reports included in this review cover 172 subacute and 90 chronic cases of electrolyte imbalances in patients with cystic fibrosis. The male:female ratio was 1.57. Electrolyte abnormalities were mostly associated with clinically inapparent fluid volume depletion, mainly affected patients aged ≤2.5 years, frequently tended to recur and often were found before the diagnosis of cystic fibrosis was established. Subacute presentation often included an history of heat exposure, vomiting, excessive sweating and pulmonary infection. History of chronic presentation, in contrast, was often inconspicuous. The tendency to hypochloremia, hypokalemia and metabolic alkalosis was similar between subacute and chronic patients, with hyponatremia being more pronounced (P < 0.02) in subacute compared to chronic presentations. Subacute cases were treated parenterally; chronic ones were usually managed with oral salt supplementation. Retention of urea and creatinine was documented in 38 % of subacute cases.
  
  
  CONCLUSIONS
  The findings of our review suggest that physicians should be aware that electrolyte abnormalities can occur both as a presenting and a recurring feature of cystic fibrosis.
authors: Pediatric Emergency Unit, De Marchi Hospital, Foundation IRCCS Ca' Granda Ospedale Maggiore Policlinico, Milan, Italy.
authors: Elisabetta
authors: E
authors: Scurati-Manzoni
authors: Emilio F
authors: EF
authors: Fossali
authors: Carlo
authors: C
authors: Agostoni
authors: Enrica
authors: E
authors: Riva
authors: Giacomo D
authors: GD
authors: Simonetti
authors: Maura
authors: M
authors: Zanolari-Calderari
authors: Mario G
authors: MG
authors: Bianchetti
authors: Sebastiano A G
authors: SA
authors: Lava
mesh_terms: D002648:Child; D003550:Cystic Fibrosis / Q000150:complications* / Q000503:physiopathology; D005260:Female; D006801:Humans; D008297:Male; D014882:Water-Electrolyte Balance / Q000502:physiology*; D014883:Water-Electrolyte Imbalance / Q000209:etiology* / Q000503:physiopathology