title: Enhancement of CURB65 score with proadrenomedullin (CURB65-A) for outcome prediction in lower respiratory tract infections: derivation of a clinical algorithm.
abstract: BACKGROUND
  Proadrenomedullin (ProADM) confers additional prognostic information to established clinical risk scores in lower respiratory tract infections (LRTI). We aimed to derive a practical algorithm combining the CURB65 score with ProADM-levels in patients with community-acquired pneumonia (CAP) and non-CAP-LRTI.
  
  
  METHODS
  We used data of 1359 patients with LRTI enrolled in a multicenter study. We chose two ProADM cut-off values by assessing the association between ProADM levels and the risk of adverse events and mortality. A composite score (CURB65-A) was created combining CURB65 classes with ProADM cut-offs to further risk-stratify patients.
  
  
  RESULTS
  CURB65 and ProADM predicted both adverse events and mortality similarly well in CAP and non-CAP-LRTI. The combined CURB65-A risk score provided better prediction of death and adverse events than the CURB65 score in the entire cohort and in CAP and non-CAP-LRTI patients. Within each CURB65 class, higher ProADM-levels were associated with an increased risk of adverse events and mortality. Overall, risk of adverse events (3.9%) and mortality (0.65%) was low for patients with CURB65 score 0-1 and ProADM ≤0.75 nmol/l (CURB65-A risk class I); intermediate (8.6% and 2.6%, respectively) for patients with CURB65 score of 2 and ProADM ≤1.5 nmol/l or CURB classes 0-1 and ProADM levels between 0.75-1.5 nmol/L (CURB65-A risk class II), and high (21.6% and 9.8%, respectively) for all other patients (CURB65-A risk class III). If outpatient treatment was recommended for CURB65-A risk class I and short hospitalization for CURB65-A risk class II, 17.9% and 40.8% of 1217 hospitalized patients could have received ambulatory treatment or a short hospitalization, respectively.
  
  
  CONCLUSIONS
  The new CURB65-A risk score combining CURB65 risk classes with ProADM cut-off values accurately predicts adverse events and mortality in patients with CAP and non-CAP-LRTI. Additional prospective cohort or intervention studies need to validate this score and demonstrate its safety and efficacy for the management of patients with LRTI.
  
  
  BACKGROUND
  Procalcitonin-guided antibiotic therapy and hospitalisation in patients with lower respiratory tract infections: the prohosp study; isrctn.org Identifier: ISRCTN: ISRCTN95122877.
authors.affiliation: Medical University Department of the University of Basel, Kantonsspital Aarau, Switzerland.
authors.forename: Werner C
authors.initials: WC
authors.lastname: Albrich
authors.forename: Frank
authors.initials: F
authors.lastname: Dusemund
authors.forename: Kristina
authors.initials: K
authors.lastname: Rüegger
authors.forename: Mirjam
authors.initials: M
authors.lastname: Christ-Crain
authors.forename: Werner
authors.initials: W
authors.lastname: Zimmerli
authors.forename: Thomas
authors.initials: T
authors.lastname: Bregenzer
authors.forename: Sarosh
authors.initials: S
authors.lastname: Irani
authors.forename: Ulrich
authors.initials: U
authors.lastname: Buergi
authors.forename: Barbara
authors.initials: B
authors.lastname: Reutlinger
authors.forename: Beat
authors.initials: B
authors.lastname: Mueller
authors.forename: Philipp
authors.initials: P
authors.lastname: Schuetz
mesh_terms: D053607:Adrenomedullin; D000368:Aged; D000369:Aged, 80 and over; D000465:Algorithms; D015331:Cohort Studies; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D011237:Predictive Value of Tests; D011379:Prognosis; D011498:Protein Precursors; D012141:Respiratory Tract Infections / Q000175:diagnosis* / Q000401:mortality
chemical_list: D011498:Protein Precursors; C088633:proadrenomedullin; D053607:Adrenomedullin