Immune-Mediated Hemolytic Anemia in an American Cocker Spaniel

Peter ChristophersonPeter Christopherson11, Elizabeth Welles, Elizabeth Welles11, , Ellen BehrendEllen Behrend22, and Elizabeth Spangler, and Elizabeth Spangler11

Auburn University College of Veterinary Medicine, Auburn University College of Veterinary Medicine, Department of PathobiologyDepartment of Pathobiology11 and Department of Clinical Sciences and Department of Clinical Sciences22

http://www.zimfamilycockers.com/Presented at SEVPAC 2008 – Permission granted for use on

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Signalment & History:• 3-year-old, spayed female,

American Cocker Spaniel• Dark red urine for 3 weeks• Pruritic with sore footpads• Tx: Antibiotics &

Ketoconazole

Physical Exam:• Lethargy and mild weight

loss • Pruritic dermatitis• “Dirty ears”• Prominent popliteal lymph

nodes

Diagnostics:• CBC, chemistry panel,

coagulation profile• Urinalysis with aerobic

culture• Thoracic/abdominal

radiographs and abdominal ultrasound

• Aspirate of popliteal lymph nodes

• Titers and PCR for tick borne diseasesPresented at SEVPAC 2008 –

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Parameter Patient Value 4/18/07 Ref Interval

HCT (%) 22.4 37-55

MCV (fL) 78.8 60-77

MCHC (g/dL) 27.7 32-36

RDW 18.3 11-17

Platelets (/uL) 227,000 164,000-510,000

MPV (fL) 16.6 8.4-13

Reticulocyte % 11.26 0-1.5

Reticulocyte Count (/uL) 320,000 0-60,000

Nucleated RBC(/100 WBC) 5

WBC (/uL) 57,040 6,000-17,000

Neutrophils (/uL) 44,491 3,000-11,400

Bands (/uL) 3,993 0-300

Monocytes (/uL) 6,274 150-1,350Presented at SEVPAC 2008 – Permission granted for use on

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400x

400x

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Interpretation

• Moderately regenerative anemia with marked spherocytosis consistent with immune-mediated hemolytic anemia

• Inflammatory leukogram

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IMHA

• Primary or secondary

• Predilections: breed, sex, age, blood type

• RBC destruction

• IgG, IgM, or complement

• Spherocyte formation

• Intravascular hemolysis

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Schalm’s Veterinary Hematology 2000, Fig. 118.1 pg 800Presented at SEVPAC 2008 – Permission granted for use on

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Schalm’s Veterinary Hematology 2000, Fig. 118.3 pg 803Presented at SEVPAC 2008 – Permission granted for use on

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Laboratory Findings

• Anemia usually regenerative

• Spherocytes

• Inflammatory leukogram

• Thrombocytosis or thrombocytopenia

• May see hyperbilirubinemia/icterus

• +/- evidence of intravascular hemolysis

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Spherocytes• Loss of RBC membrane

without loss of cell volume

• Partial phagocytosis

• Identifiable on canine blood smears

• Cells are round with smooth margins

• Decreased diameter and central pallor

• Ddx: snake envenomation, bee sting, zinc toxicity, inherited membrane or enzyme defects

Bessis M: Blood Smears Reinterpreted, Springer-Verlag, 1977, pgs 53 & 97

Normal RBC

Spherocyte

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Acknowledgements & References

1. Latimer KS, Mahaffey EA, and Prasse KW. Duncan & Prasse’s Veterinary Laboratory Medicine Clinical Pathology, 4th edition. Iowa State Press, 17, 2003.

2. Stockham SL and Scott MA. Veterinary Clinical Pathology, 1st edition. Iowa State Press, 122-126, 2002.

3. Weiss DJ and Brazzell JL. Detection of Activated Platelets in Dogs with Primary Immune-Mediated Hemolytic Anemia. J Vet Intern Med 20: 682-686; 2006.

4. Piek CJ, Junius G, Dekker A, Schrauwen E, Slappendel RJ, and Teske E. Idiopathic Immune-Mediated Hemolytic Anemia: Treatment Outcome and Prognostic Factors in 149 Dogs. J Vet Intern Med 22:366-373; 2008.

Uschi Wohlfert, Debbie Czerkawski, Amy Hall, Donna Shiver, and Stephany Spencer

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