title: Efficient removal of colistin A and B in critically ill patients undergoing CVVHDF and sorbent technologies.
abstract: BACKGROUND
  Colistin pharmacokinetics data are scarce regarding patients undergoing renal replacement therapy (RRT), or even absent as in patients treated with sorbent technologies potentially capable of removing colistin by extensive absorption on many polymeric materials.
  
  
  METHODS
  Twelve septic shock patients with acute kidney injury (AKI) undergoing RRT [continuous venovenous hemodiafiltration (CVVHDF) n = 7, coupled-plasma filtration adsorption-HF (CPFA-HF) n = 4, hemoperfusion n = 1] treated with colistin methanesulfonate at a dose of 4.5 × 10(6) U bid were studied. Colistin A (Col-A) and colistin B (Col-B) concentrations on plasma and effluent at time 0, 0.2, 1, 3, 6, 12, 24 and 48 h were determined by the liquid chromatography-tandem mass spectrometry method.
  
  
  RESULTS
  With CVVHDF the sieving coefficient was lower for Col-A, peaked early (0.40 for Col-A at 10 min, and 0.59 for Col-B at 3 h) and declined after 48 h (0.22 and 0.30 for Col-A and Col-B, respectively). Colistin's filter clearance showed a similar pattern, with the highest clearance value of 18.7 ml/min for Col-B at 1 h. With CPFA-HF after the cartridge the Col-A and Col-B levels were negligible (<0.2 mg/l) or not detectable. The sum of the effluent and cartridge clearances reached values of 30 and 40 ml/min for Col-A and Col-B, respectively. With hemoperfusion the postcartridge concentrations for Col-A and Col-B were about 30 % lower than those determined precartridge.
  
  
  CONCLUSIONS
  During CPFA-HF and CVVHDF, the extent of colistin removal is high, and patients should receive an unreduced dosage. However, due to risk of accumulation in long-term administration colistin plasma levels determination is recommended.
authors.affiliation: Nefrologia, Dialisi e Trapianto U, Dipartimento di Medicina Generale e Specialistica, Citta' della Salute e della Scienza di Torino, Ospedale CTO, Via G. Zuretti 29, 10126, Turin, Italy. filippo.mariano@hotmail.it.
authors.forename: Filippo
authors.initials: F
authors.lastname: Mariano
authors.affiliation: Centro Regionale Antidoping e di Tossicologia "Alessandro Bertinaria", Orbassano, TO, Italy.
authors.forename: Marta
authors.initials: M
authors.lastname: Leporati
authors.affiliation: Dipartimento di Anestesia e Rianimazione, Anestesia e Rianimazione 5, Citta' della Salute e della Scienza di Torino, Ospedale CTO, Turin, Italy.
authors.forename: Paola
authors.initials: P
authors.lastname: Carignano
authors.affiliation: Dipartimento di Chirurgia Generale e Specialistica, Chirurgia Plastica Grandi Ustionati, Citta' della Salute e della Scienza di Torino, Ospedale CTO, Turin, Italy.
authors.forename: Maurizio
authors.initials: M
authors.lastname: Stella
authors.affiliation: Centro Regionale Antidoping e di Tossicologia "Alessandro Bertinaria", Orbassano, TO, Italy.|Dipartimento di Chimica, Università degli Studi di Torino, Turin, Italy.
authors.forename: Marco
authors.initials: M
authors.lastname: Vincenti
authors.affiliation: Nefrologia, Dialisi e Trapianto U, Dipartimento di Medicina Generale e Specialistica, Citta' della Salute e della Scienza di Torino, Università degli Studi di Torino, Turin, Italy.
authors.forename: Luigi
authors.initials: L
authors.lastname: Biancone
mesh_terms: D058186:Acute Kidney Injury / Q000150:complications / Q000378:metabolism / Q000628:therapy*; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D002853:Chromatography, Liquid / Q000379:methods; D003091:Colistin / Q000493:pharmacokinetics*; D016638:Critical Illness / Q000628:therapy*; D005260:Female; D005500:Follow-Up Studies; D017583:Hemodiafiltration / Q000379:methods*; D006801:Humans; D008297:Male; D013058:Mass Spectrometry; D008875:Middle Aged; D012772:Shock, Septic / Q000150:complications / Q000188:drug therapy / Q000378:metabolism; D016060:Sorption Detoxification / Q000379:methods*
chemical_list: C579082:colistin A, Paenibacillus polymyxa JB05-01-1; C579083:colistin B, Paenibacillus polymyxa JB05-01-1; D003091:Colistin
keywords: CVVHDF; Colistin extracorporeal removal; Colistin sieving coefficient; Coupled plasmafiltration adsorption; Hemoperfusion