Immune-mediated neutropenia in 2 dogs

Immune-Mediated Neutropenia in a Miniature Poodle

A 10 yr old spayed female toy poodle was presented to a tertiary referral center for a 10 day history of waxing and waning lethargy, vomiting, diarrhea, and anorexia. An immune-mediated neutropenia (IMN) was suspected to be the underlying cause of her clinical signs. A bone marrow aspirate was obtained from the chostochondral junction of the 11th and 12th ribs on the right side and provided a definitive diagnosis of IMN. A positive response to therapy and repeat blood work further confirmed the diagnosis. Obtaining bone marrow aspirates from the chostochondral junction is a safe, cheap, and reliable method of diagnosing IMN and can be performed in the private practice setting with light sedation and minimal need for specialized equipment.

Suspected immune-mediated neutropenia and corticosteroid responsive pancytopenia in a Portuguese water dog

An 8-year-old spayed Portuguese water dog was presented with dysuria, lethargy, and anorexia. A profound neutropenia and pancytopenia were identified. Bone marrow aspirates revealed neutrophilic hyperplasia, a significant left shift, and toxic changes, suggesting immune-mediated destruction as a likely underlying mechanism. Immunosuppressive therapy was instituted and clinical signs improved.

Primary immune-mediated neutropenia in a cat

An 18-month-old male castrated indoor Himalayan cat was presented for recurrent fever, lethargy, and uveitis. Persistent neutropenia was identified and tests for infectious disease and bone marrow cytology were performed. Primary immune-mediated neutropenia was diagnosed and successfully treated. At the time of writing this report, 24 mo after the initial diagnosis. the patient was clinically normal and not receiving therapy.

Glucocorticoid-dependent hypoadrenocorticism with thrombocytopenia and neutropenia mimicking sepsis in a Labrador retriever dog

Glucocorticoid-deficient hypoadrenocorticism (GDH) with immune-mediated-neutropenia (IMN) and -thrombocytopenia (IMT) were diagnosed in a 3-year-old Labrador retriever dog. Glucocorticoid-deficient hypoadrenocorticism is rare and diagnostically challenging as clinical signs and laboratory abnormalities are often nonspecific. Immune-mediated cytopenias and other autoimmune disorders, as part of an autoimmune polyglandular syndrome have been reported with hypoadrenocorticism in humans. This is the first reported case of hypoadrenocorticism and bicytopenia in a dog.

Immune mediated neutropenia and thrombocytopenia in 3 giant schnauzers

Neutropenia, thrombocytopenia, and splenomegaly were recognized in 3 adult female giant schnauzers. Antineutrophil antibodies were demonstrated in 2 dogs. Following splenectomy, administration of prednisone and azathioprine resulted in normalization of neutrophil and platelet numbers in all dogs.

An indirect flow cytometric test for detection of anti-neutrophil antibodies in dogs

OBJECTIVE

To develop a clinically applicable assay for detection of serum anti-neutrophil antibodies in dogs.

SAMPLE POPULATION

Serum samples of 20 healthy dogs and 20 sick dogs.

PROCEDURES

An indirect immunofluorescence assay was developed in which canine serum was incubated with paraformaldehyde-fixed neutrophils and subsequently incubated with fluorescein-conjugated rabbit anti-dog IgG. Neutrophil median fluorescence intensity and the percentage of neutrophils with an increase in fluorescence intensity were determined by use of a flow cytometer.

RESULTS

Neutrophils incubated with serum from healthy and sick dogs had a normally distributed curve when displayed as a histogram. Alloantibodies or immune complexes that significantly affected test results were not detected. Hyperglobulinemia did not appear to affect test results. The neutrophil donor did not significantly affect test results. With 1 exception, results for the sick dogs did not differ appreciably from those for healthy dogs. Serum from a dog with steroid-responsive neutropenia had a greater neutrophil fluorescence value and percentage of neutrophils with an increase in fluorescence intensity, compared with either healthy or sick dogs.

CONCLUSIONS AND CLINICAL RELEVANCE

The indirect immunofluorescence test gave consistent results for healthy and sick dogs and detected anti-neutrophil antibodies in a dog with steroid-responsive neutropenia. Definitive evaluation of the test will be dependent on evaluation of persistently neutropenic dogs and correlation of test results with a response to immunosuppressive therapy.

Evaluation of clinicopathologic features, response to treatment, and risk factors associated with idiopathic neutropenia in dogs: 11 cases (1990–2002)

OBJECTIVE

To evaluate the clinicopathologic features, response to treatment, and risk factors associated with idiopathic neutropenia in dogs.

DESIGN

Retrospective case series.

ANIMALS

11 dogs.

PROCEDURES

Medical records of dogs with idiopathic neutropenia were reviewed. Signalment, history, clinical signs, and response to treatment were recorded and compared with that in dogs with neutropenia attributable to known causes and to dogs without neutropenia (controls).

RESULTS

Compared with dogs with neutropenia attributable to known causes, dogs with idiopathic neutropenia had lower neutrophil counts and were younger. When compared with control dogs, age < 4 years was identified as a risk factor for developing idiopathic neutropenia. In all dogs with idiopathic neutropenia, remission of neutropenia occurred within 18 days after administration of prednisone (2 to 4 mg/kg [0.9 to 1.8 mg/lb], PO, daily) and no serious complications or infections developed.

CONCLUSIONS AND CLINICAL RELEVANCE

An immune-mediated pathogenesis should be considered for dogs with idiopathic neutropenia in which the cause is not known. Severe neutropenia and young age were significantly associated with idiopathic neutropenia in dogs. Prognosis appeared to be excellent with prednisone treatment.