Immune-Mediated Hemolytic Anemia (IMHA) - Genetics Study in Spaniel Breeds

English cocker spaniel

Immune-Mediated Hemolytic Anemia, or IMHA, is an autoimmune disease in dogs in which the body attacks its own red blood cells. This can lead to very low red blood cell counts (anemia) that require multiple blood transfusions. It can also predispose dogs to forming blood clots, mostly in the lungs or in the brain. Treatment can require extended hospitalization, drugs that suppress the immune system, and often blood thinners. Some dogs do quite well with minimal treatment, however for many others the disease is unfortunately fatal.

Study goals

English Springer Spaniel

Dr. Steven Friedenberg and the Canine Genetics Laboratory at the University of Minnesota College of Veterinary Medicine are working to identify gene mutations responsible for the development of IMHA. Our goal is to use this research to better understand the disease mechanism and disease triggers, and also to develop a test that can help breeders decrease the incidence of the disease. We are also interested in using the results of our research to help predict disease severity and response to treatment.

Contact us

Canine Genetics Lab
University of Minnesota
1988 Fitch Ave
AS/VM 295
St. Paul, MN 55108

[email protected]

Enrollment criteria

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  • American Cocker Spaniels
  • English Cocker Spaniels
  • English Springer Spaniels
  • Clumber Spaniels

Requirements to participate

  • Dogs of any age that have been diagnosed with IMHA, either currently or in the past
  • Your willingness to volunteer a blood sample from your dog for genetics research

Study information

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Information for owners

Cocker Spaniel on a bridge

Please contact Dr. Friedenberg (or have your veterinarian contact him) at [email protected] if you are interested in having your dog donate a blood sample. Dr. Friedenberg will discuss with you whether your dog is a candidate for the study, and obtain the necessary medical records from either you or your dog’s veterinarian.

If your dog meets the criteria for the study, we will send your veterinarian a prepaid shipping label to send us a blood sample from your dog. You can then schedule a brief appointment with your veterinarian for a blood draw. After the visit, your veterinarian will send the blood sample to us, along with a consent form and any relevant medical records.

Please also bring a copy of your dog’s pedigree to your veterinarian if you have a copy, however this is not strictly necessary. You can also e-mail it to Dr. Friedenberg directly.

Information for veterinarians

Clumber Spaniel

If you have any clients who you think would be interested in participating in our study, or if your client has approached you about this study, the following information should be helpful.

We are soliciting DNA samples from American Cocker Spaniels, English Cocker Spaniels, English Springer Spaniels, and Clumber Spaniels that you are currently treating or have treated in the past for primary IMHA.

Inclusion and exclusion criteria for the study are as follows:

Inclusion criteria

  • CBC documenting HCT < 30%
  • Positive results on one of the following tests:
    • Slide autoagglutination test (macro or micro)
    • Pathologist-reviewed blood smear documenting spherocytosis
    • Coombs test with a titer of 1:64 or greater
    • Flow cytometry documenting erythrocyte surface-bound IgG

Exclusion criteria

  • Thoracic radiographs showing evidence of disease consistent with neoplasia (at the time of diagnosis)
  • Abdominal radiographs showing evidence of disease consistent with neoplasia or a foreign metallic object (at the time of diagnosis)
  • Abdominal ultrasound showing evidence of systemic disease at the time of diagnosis
  • Evidence of true infection with any erythrocyte-borne pathogen or rickettsial disease based upon blood smear, culture, convalescent IFA, or PCR

At a minimum, patients must meet (or have met) both inclusion criteria concurrently. It is not necessary to have evaluated patients for all of the exclusion criteria. However, if you did perform any of the listed exclusion criteria tests and your patient meets one of them, unfortunately we cannot include that patient in the study.

If you have any clients meeting the above criteria who might be interested in donating a blood sample for genetics research, please e-mail Dr. Steven Friedenberg at [email protected] with your contact details and we will arrange a time to discuss the case. If your patient qualifies, we will send you a prepaid shipping label to send us the sample at our expense. The study requires the following to be shipped:

  • 4-5 mL of blood in 1 or 2 EDTA/purple top tubes
  • Relevant medical records to confirm the diagnosis
  • A filled out consent form
  • A copy of the dog’s pedigree, if provided by the owner

We will provide you with further shipping details once we ensure that your patient is a good candidate for the study.

About the Investigator

Dr. Steven Friedenberg with poodle

Dr. Steven Friedenberg is a board-certified veterinary critical care specialist and a geneticist, and he is currently an Associate Professor at the University of Minnesota College of Veterinary Medicine. He earned his veterinary degree at Cornell University, completed his residency at The Ohio State University, and holds a PhD in genetics from North Carolina State University. He is passionate about studying canine Addison’s disease, immune-mediated hemolytic anemia, and other autoimmune diseases. He also is interested in developing novel bioinformatics and immunologic tools for the canine scientific community.