Veterinary Medicine - Congenital, Hereditary Immunodeficiency and Immune-Mediated Diseases

Question 1

When does congenital immunodeficiency become a relevant as a DD

Answer 1

Young animal (generally from birth to 6 months), commonly pure breed, suffering from recurrent episodes of disease involving several body systems, which responds to supportive treatment (i.e. antibiotics)

Question 2

Canine Leukocyte Adhesion Deficiency (CLAD) - Signalment

Answer 2

Young Irish-Setter / Irish-Setter Mix

Question 3

Canine Leukocyte Adhesion Deficiency (CLAD) - Common CBC finding

Answer 3

Persistent neutrophilia

Question 4

Canine Leukocyte Adhesion Deficiency (CLAD) - Clinical signs

Answer 4

Fever, Lymphadenopathy, Lameness (Mainly due to bone disorders), Recurrent skin infections, Umbilical vein infection, Failure to gain weight

Question 5

Canine Leukocyte Adhesion deficiency (CLAD) - Diagnosis

Answer 5

Genetic test for mutation in the CD18 gene

Question 6

Trapped Neutrophil Syndrome - Most affected breed

Answer 6

Border Collie

Question 7

Trapped Neutrophil Syndrome - Most common CBC finding

Answer 7

Neutropenia

Question 8

Trapped Neutrophil Syndrome - Common Complication

Answer 8

Immune-mediated polyarthritis (Formation of immune complexes secondary to recurrent infections)

Question 9

Trapped Neutrophil Syndrome - Diagnosis

Answer 9

Combination of neutropenia + Bone marrow with myeloid hyperplasia and many trapped mature neutrophils. Genetic testing

Question 10

Chediak Higashi Syndrome - Signalment, affected blood cells and most common clinical signs

Answer 10

Smoke-blue Persian cats with lighter / white coat color and reddish - orange Irises. Neutrophils and Platelets. Thrombocytopathy - bleeding tendencies. Impaired neutrophil function - increased susceptibility to infections.

Question 11

Cyclic hematopoiesis of Collies - What is the most affected blood cell and why?

Answer 11

Neutrophil. This disease is characterized by hematopoiesis arrest every 11-14 days, and neutrophils have the shortest half-life (6 hours)

Question 12

Cyclic Hematopoiesis of Collies - What are other Physical sign/Concurrent Disease that can give us a clue to this disease?

Answer 12

Skin - Coat Color Dilution. Also - Nose color is Grey instead of Black. CKD - Because of Amyloidosis.

Question 13

Cyclic Hematopoiesis of Collies - Possible treatments

Answer 13

GM-CSF. Bone marrow transplant

Question 14

Pelger-Huet Syndrome - Affected cell and how are they affected?

Answer 14

All granulocytes - Neutrophils, Eosinophils, Basophils. Hypo-segmentation (band shape)

Question 15

Pelger-Huet Syndrome - What is the fate of a homozygous puppy?

Answer 15

Fetal death

Question 16

IgA Deficiency - Common systems affected

Answer 16

Skin, Respiratory tract, GI, Urinary

Question 17

IgA Deficiency - Diagnosis and what is an important factor in the diagnosis

Answer 17

Quantification of IgA Antibody levels. *Compare results to other litter mates if possible. Important to check after 12-18 months because IgA levels can normalize at that time

Question 18

IgA Deficiency - Treatment and Prognosis

Answer 18

No specific treatment. Treat infections as they arise. Good

Question 19

Transient hypoglobulinemia - What immunoglobulins are missing?

Answer 19

IgG, IgA

Question 20

Transient Hypoglobulinemia - When is the onset of the disease and when does remission occur?

Answer 20

2 Months old (when passive immunity decreases). 5-7 Months (Immunoglobulins starts being produced)

Question 21

X-Linked Severe Combined Immune Deficiency (SCID) - What cells are affected? Prognosis?

Answer 21

Lymphocytes: T-Cells, B-Cells, NK Cells. Grave. Death at few months old

Question 22

Immune-mediated neutropenia - Signalment

Answer 22

< 4 Years

Question 23

Immune-mediated neutropenia - Main clinical sign

Answer 23

Fever

Question 24

Immune-mediated neutropenia - Diagnosis & Treatment & Prognosis

Answer 24

Exclude: infection, Bone marrow suppression , Anaphylactic Response. Working diagnosis: Neutropenia + Myeloid hyperplasia on BM cytology/biopsy. Treatment: Glucocorticoids. Prognosis: Great. Rapid response with long lasting effect

Question 25

Immune-mediated polyarthritis (IMPA) - Signalment (non-erosive)

Answer 25

Young - adult large breed dogs

Question 26

Immune-mediated polyarthritis (IMPA) - Signalment (Erosive)

Answer 26

Adult small breed dogs

Question 27

Immune-mediated polyarthritis (IMPA) - What gives a clue in physical exam that helps differentiate between IMPA and infectious arthritis?

Answer 27

Infectious: Tends to be in proximal joints (Elbow, Hip). Usually in a single joint. IMPA: Tends to affect distal joints (Carpus, Tarsus). Usually affecting multiple joints

Question 28

Immune-mediated polyarthritis (IMPA) - Treatment & Monitoring (2 Methods)

Answer 28

Treatment: GC +/- 2nd Immunosuppression (e.g. Leflunomide / Cyclosporine). Monitoring: 1) Repeat arthrocentesis 2) CRP Levels

Question 29

Immune-mediated polyarthritis (IMPA) - clinical signs / PE findings

Answer 29

Fever (20-25% of cases of fever of unknown origin), Lethargy, Anorexia, Lameness - can be transient / recurrent / alternating between legs , Back pain, Joint pain , Joint effusion

Question 30

Immune-mediated polyarthritis (IMPA) - Joint effusion and lameness are always a feature of IMPA (True / False)

Answer 30

False - Only 30%-40% of cases for both.

Question 31

Immune-mediated polyarthritis (IMPA) - What type of cells do you expect to see in a slide from arthrocentesis of a normal joint? How many cells per HPF is normal?

Answer 31

Mononuclear cells (Monocytes, Macrophages). 1-3 Cells per HPF

Question 32

Immune-mediated polyarthritis (IMPA) - Prognosis (All syndromes in order from best to worse)

Answer 32

Underlying cause of polyarthritis resolved: Excellent. Primary - Non-erosive (Dog): Good. Erosive/Non-erosive (Cat): Good. Erosive (Dog): Poor.

Question 33

Immune-mediated polyarthritis (IMPA) - Other DDs

Answer 33

Septic arthritis , Trauma, Degenerative joint disease , Neoplasia, Hemarthrosis

Question 34

Immune-mediated polyarthritis (IMPA) - The difference between IMPA and infectious arthritis is the presence of bacteria on cytology and C&S (True/False)

Answer 34

False. The majority of samples taken from joints come back negative (on cytology and C&S) - 50-70% False negative

Question 35

Immune-mediated polyarthritis (IMPA)- Diagnosis

Answer 35

1) History and clinical signs. 2) Search for causes for secondary IMPA: CBC, Panel + CRP, UA, X-rays (affected joints, Chest), Abdominal US, Screening for infectious diseases (e.g. Ehrlichiosis, Leishmaniasis, Babesiosis). 3) Arthrocentesis from multiple joints - Macroscopic (Color, Texture, Volume) and cytological (Cellularity, Predominate cell, Presence of infectious agents) evaluation. Samples for bacterial C&S and mycology (optional).

Question 36

What are the common categories of DDs for pathologies / chronic disease in neonate-young animal aside from “Developmental” (i.e. Congenital immunodeficiency)

Answer 36

Metabolic (e.g. Congenital hypothyroidism, Hypopituitarism, cPSS, cCKD). Nutritional (e.g. Malnutrition, Malabsorption, Maldigestion). Infections (e.g. FeLV, Distemper)

Question 37

A young Shar-Pei is diagnosed with kidney and liver abnormalities and sufferers from occasional lameness (multiple limbs affected). What is an important DD?

Answer 37

Amyloidosis (“Shar-Pei Fever”)

Question 38

Shar Pei Fever - Clinical signs

Answer 38

Recurrent Fever, Joint swelling, Lameness (Multiple limbs, Swaps between limbs), Vomiting, Diarrhea, Jaundice, PUPD, Oliguria / Anuria, Pleural / Abdominal / Pericardial / Peripheral edema

Question 39

Shar Pei Fever - Treatment

Answer 39

Colchicine (Possibly slowing accumulation of Amyloid). NSAIDs in flare ups (Caution when kidney disease is suspected)

Question 40

Secondary IMHA - DDs & And specific diagnostics for each

Answer 40

Dog: Babesia (Blood Smear / PCR), Ehrlichiosis (PCR), Leishmaniasis (PCR / Serology / Cytology), Anaplasma (PCR / Blood smear). Cat: Mycoplasma (PCR / Blood Smear), FeLV (Snap against Antigen). Vaccines (Hx). Drugs (Hx). Neoplasia / Inflammatory diseases (Panel / CBC / UA / X-Rays / US)

Question 41

IMHA Treatment - When can you start tapering-off steroids treatment and under what conditions?

Answer 41

Every 2 weeks and PCV, Spherocytosis, Bilirubin all begin to normalize (25% Reduction). In cases where 2nd immunosuppression is used - Same as the above but while keeping the 2nd immunosuppression at the same dosage - a greater reduction of steroids can be applied (25-50% Reduction)

Question 42

IMHA - Monitoring

Answer 42

PCV, Spherocytosis, Reticulocytosis, Bilirubin, In-slide Agglutination / Coomb’s Test. Monitor side effects of GC and 2nd Immunosuppressants (Including CBC, Panel and UA - Important for UTIs)

Question 43

Immune-mediated thrombocytopenia - Treatment

Answer 43

Treat underlying cause if possible. Doxycycline (for possible blood-borne infection). Immunosuppression: 1st line: Prednisone hIVIG / Vincristine / Romiplostin. 2nd line: Cyclosporine / Azathioprine / Cellcept. 3rd Line: Splenectomy. Blood transfusion

Question 44

IMHA - Treatment

Answer 44

Treat underlying cause if possible. Glucocorticoids (Immunosuppressive dosage). If necessary - 2nd immunosuppression (e.g. Azathioprine / Cyclosporine / Cellcept). Anti-coagulants / Anti-thrombotics (e.g. Clopidogrel / Low-dose aspirin /LMWH / /Rvivaroxaban). Blood transfusion (Packed RBC >> Whole blood). Splenectomy (Salvage procedure)