title: Alloimmune neonatal neutropenia and neonatal isoerythrolysis in a Thoroughbred colt.
abstract: A 3-day-old Thoroughbred colt was originally presented for treatment of neonatal isoerythrolysis, which was treated with a blood transfusion. However, persistent neutropenia was observed despite the absence of detectable infection. Subsequently, a granulocyte agglutination test was performed by incubating the colt's neutrophils with the mare's serum; results were positive, leading to a clinical diagnosis of alloimmune neonatal neutropenia. The diagnosis was further supported via flow cytometric analysis. The colt was hospitalized and treated prophylactically with antimicrobials and 4 separate doses of recombinant human granulocyte colony-stimulating factor (rhG-CSF; 1.4-3.5 µg/kg, subcutaneously) in attempts to maintain the neutrophil count within reference intervals over a 4-week period. The colt's neutrophil count increased after administration of rhG-CSF and eventually stabilized within reference intervals by day 20. The colt maintained normal neutrophil counts after discharge and was reportedly healthy at 6 months of age. Alloimmune neonatal neutropenia should be considered in foals with persistent neutropenia in the absence of infection. Alloimmune neonatal neutropenia can be treated with prophylactic antimicrobials combined with rhG-CSF with a favorable outcome.
authors.affiliation: Lloyd Veterinary Medical Center, Department of Veterinary Clinical Sciences, College of Veterinary Medicine, Iowa State University, Ames, IA 50011, USA.
authors.forename: David M
authors.initials: DM
authors.lastname: Wong
authors.forename: Cody J
authors.initials: CJ
authors.lastname: Alcott
authors.forename: Sandra K
authors.initials: SK
authors.lastname: Clark
authors.forename: Douglas E
authors.initials: DE
authors.lastname: Jones
authors.forename: Phyllis G
authors.initials: PG
authors.lastname: Fisher
authors.forename: Brett A
authors.initials: BA
authors.lastname: Sponseller
mesh_terms: D000818:Animals; D000831:Animals, Newborn / Q000276:immunology; D000890:Anti-Infective Agents / Q000627:therapeutic use; D001803:Blood Transfusion / Q000662:veterinary; D003937:Diagnosis, Differential; D004899:Erythroblastosis, Fetal / Q000175:diagnosis / Q000628:therapy / Q000662:veterinary*; D005434:Flow Cytometry / Q000662:veterinary; D016179:Granulocyte Colony-Stimulating Factor / Q000627:therapeutic use; D006734:Horse Diseases / Q000175:diagnosis* / Q000276:immunology; D006736:Horses; D007958:Leukocyte Count / Q000662:veterinary; D008297:Male; D009503:Neutropenia / Q000175:diagnosis / Q000188:drug therapy / Q000276:immunology / Q000662:veterinary*; D009504:Neutrophils; D011994:Recombinant Proteins / Q000627:therapeutic use
chemical_list: D000890:Anti-Infective Agents; D011994:Recombinant Proteins; D016179:Granulocyte Colony-Stimulating Factor