title: Stomatocytosis in 7 related Standard Schnauzers.
abstract: BACKGROUND
  Hereditary canine stomatocytosis has been described in purebred Alaskan Malamutes, Drentse Patrijshonds, and Miniature Schnauzers. In humans, hereditary stomatocytosis is a heterogeneous group of congenital disorders characterized by the presence of stomatocytes in blood, increased osmotic fragility, and frequently, hemolytic anemia.
  
  
  OBJECTIVE
  Our objective was to describe hematologic findings and RBC characteristics in 7 closely related Standard Schnauzers with stomatocytosis.
  
  
  METHODS
  The following parameters were measured using an automated analyzer: HCT, RBC, hemoglobin (Hb) concentration, MCV, MCH, MCHC, red cell distribution width (RDW), WBC, platelet count, mean platelet volume (MPV), thrombocrit (PCT), and platelet distribution width (PDW). Differential leukocyte count, platelet estimate, reticulocyte count, and the percentage of stomatocytes in blood films were microscopically evaluated. An osmotic fragility test of RBCs and measurement of intracellular Na+, K+, and 2,3-diphosphoglycerate (2,3-DPG) concentrations were also performed.
  
  
  RESULTS
  The affected dogs had macrocytosis (80.0 +/- 4.2 fL, reference interval 60-76 fL), decreased MCHC (29.3 +/- 0.8 g/dL, reference interval 32-39 g/dL), slightly increased RDW (17.3 +/- 0.4%, reference interval 12-16%), and an increased reticulocyte count (1.55 +/- 0.77%, reference interval <1%). The percentage of stomatocytes in blood films varied from 0.6 to 18.9% of all RBCs. Erythrocyte osmotic fragility and intracellular Na+ (138.1 +/- 3.2 mmol/L; controls 99 +/- 6.1 mmol/L), K+ (8.1 +/- 0.8 mmol/L; controls 6.1 +/- 0.5 mmol/L), and 2,3-DPG (21.9 +/- 2.0 micromol/g Hb; controls: 14.6 +/- 3.3 micromol/g Hb) concentrations were increased in dogs with stomatocytosis.
  
  
  CONCLUSIONS
  Hematologic findings and the metabolic defects in RBCs in these Standard Schnauzers were consistent with a diagnosis of stomatocytosis. Parentage analysis suggests that stomatocytosis in Standard Schnauzers may have a hereditary component.
authors.affiliation: Clinica Veterinaria Gran Sasso, Milano, Italy. u.bonfa@flashnet.it
authors.forename: Ugo
authors.initials: U
authors.lastname: Bonfanti
authors.forename: Stefano
authors.initials: S
authors.lastname: Comazzi
authors.forename: Saverio
authors.initials: S
authors.lastname: Paltrinieri
authors.forename: Walter
authors.initials: W
authors.lastname: Bertazzolo
mesh_terms: D000818:Animals; D004283:Dog Diseases / Q000097:blood* / Q000235:genetics*; D004285:Dogs; D004909:Erythrocyte Indices / Q000662:veterinary; D004913:Erythrocytes, Abnormal / Q000166:cytology*; D005260:Female; D008297:Male; D009996:Osmotic Fragility; D010375:Pedigree