title: [Neutropenia in dogs: etiology and prognostic factors].
abstract: OBJECTIVE
  The aim of this retrospective study was to evaluate frequency, prognostic factors, and differences for various etiologies of neutropenia in dogs.
  
  
  METHODS
  A total of 391 dogs with neutrophil counts < 2.78 x 109/l (January 2008 to December 2012) were included and, depending on the etiology of neutropenia, assigned to seven diagnostic groups: nonbacterial infectious disease, increased demand due to marked inflammation, drug-associated, bone-marrow diseases, immune-mediated, physiologic, miscellaneous. Absolute neutrophil counts, evidence of neutrophil toxicity or left shift, case history, rectal temperature, hospitalization, and survival were compared among groups.
  
  
  RESULTS
  Increased demand due to marked inflammation (90/391, 23%) and nonbacterial infectious disease (70/391, 18%) were the most common causes for neutropenia, followed by drug-associated neutropenia (43/391, 11%) and bone-marrow disease (32/391, 8%). Immune-mediated and physiologic neutropenia (both 16/391, 4%) were uncommon. Almost one third (124/391, 32%) of dogs were assigned to the miscellaneous group. Absolute neutrophil counts were significantly higher (p < 0.01) in dogs of the physiologic and miscellaneous groups than in the other groups. Dogs with immune-mediated neutropenia or nonbacterial infectious disease displayed significantly lower absolute neutrophil counts than dogs with neutropenia due to an increased demand (p < 0.001) and were most commonly referred with a history of fever (11/16, 69%) or gastrointestinal signs (52/70, 74%), respectively. Neutrophil toxicity and left shift were most commonly associated with an increased demand due to marked inflammation (60/90 and 25/90, 67% and 28%, respectively) and the mortality rate was highest in this group (32/90, 36%).
  
  
  CONCLUSIONS
  Neutrophil toxicity and left shift are associated with an increased demand due to marked inflammation and may indicate a poor prognosis. The lower the absolute neutrophil count, the greater the probability of an immune-mediated neutropenia.
  
  
  CONCLUSIONS
  Neutropenia should be assessed in context with case history, clinical examination, and neutrophil morphology.
authors.affiliation: Andrea Manuela Cook, Berrenrather Straße 1a, 50169 Kerpen, E-Mail: andrea.manuela.cook@gmail.com.
authors.forename: Andrea M
authors.initials: AM
authors.lastname: Cook
authors.forename: Natali
authors.initials: N
authors.lastname: Bauer
authors.forename: Reto
authors.initials: R
authors.lastname: Neiger
authors.forename: Christine
authors.initials: C
authors.lastname: Peppler
authors.forename: Andreas
authors.initials: A
authors.lastname: Moritz
mesh_terms: D000818:Animals; D004283:Dog Diseases / Q000097:blood / Q000175:diagnosis* / Q000209:etiology*; D004285:Dogs; D009503:Neutropenia / Q000097:blood / Q000175:diagnosis / Q000209:etiology / Q000662:veterinary*; D009504:Neutrophils / Q000473:pathology; D011379:Prognosis; D012189:Retrospective Studies
keywords: Toxic neutrophils; immune-mediated; increased demand; inflammation; left-shift; survival rate