Immunosuppressive Therapy Flashcards
Name a few common Immune Mediated Diseases
- Immune mediated hemolytic anemia
- immune mediated thrombocytopenia
- Evans syndrome (IMHA +IMTP
- Immune mediated polyarthritis
- IBD
Glucocorticoids include __ and __ . Once you get a diagnosis, what immunosuppressive therapies might you add?
Glucocorticoids include prednisolone and dexmethasone. Other immunosuppressive therapies include azathioprine, cyclosporine, chorambucil, leflunomide ad mycophenolate mofetil
when might you use an anticoagulant as an adjunctive immunosuppressive therapy?
cases of IMHA, IBD, PLN
Glucocorticoids are __ and __ with a relatively rapid onset that shows improvement in __ usually. Its also __.
Glucocorticoids are anti inflammatory and immunosuppressive with a relatively rapid onset that shows improvement in 7 days usually. Its also cheap.
T/F: Prednisone is more potent than dexmethasone
F, dexmethasone 7-10x more potent
Side Effects of Glucocorticoids
- PU/PD
- muscle atrophy and weakness
- Iatrogenic hyperadrenocorticism
- vacuolar hepatopathy
- infections, sepsis
- GI ulceration
- Hypercoagulability
- Cats -diabetes, CHF
should you taper steroids before or after other medications?
before
Explain dosing of glucocorticoids
The starting point is 2mg/kg/day which works for smaller animals but as the dose gets larger so do the side effects so you want to cap the dose at 60mg/day (this is anecdotal but based on clinical signs)
Briefly explain steroid hepatopathy
when on prednisone/steroids the liver can develop disease that is reversible once the prednisone treatment stops. While on predisone they may have the following:
- ALP should be higher than ALT
- ALP and GGT can be very high
- Total bilirubin should never be high
- Indirect liver function parameters should be normal
Contradictions of Glucocorticoids
- Diabetes mellitus
- Infections
- Hyperadrenocorticism
- NSAID therapy (24-72 hr washout ideally
what does “remission” of glucocorticoid therapy look like? and how should you taper the steroid dose once an animal reaches remission?
Remission for IMHA is a near normal HCT and for ITP is near normal platelets, for both diseases they should be in remission for 2 weeks before starting to taper doses. The steroid dose can be decreased 25% of the original dose every 2-4 weeks until discontinued or at the lowest effective dose. Go to EOD and every 3 day dosing before stopping
T/F: Azathioprine is safe to use in cats
F, they don’t make enough of the enzyme (TPMT) for metabolism so it will build up
Azathioprine __ purine synthesis which disrupts __ proliferation. It has a __ onset and is __. This drug should be tapered __ prednisone for __ months.
Azathioprine inhibits purine synthesis which disrupts lymphocyte proliferation. It has a slow onset and is cheap. This drug should be tapered after prednisone for 2-3 months.
explain the side effects of azathioprine
- Cytopenias (bone marrow suppression) 2-3 weeks
- hepatotoxicity 1-4 weeks
- chronic subclinical anemia (PCV > 25-30%)
- GI signs - mild and self limiting
azathioprine hepatotoxicity
Concurrent prednisone administration can make it hard to monitor liver enzymes (prednisone should cause a cholestatic pattern). Azothioprine increases ALT +/- bilirubin. Discordant ALT to ALP, and increased bilirubin.
Briefly explain Cyclosporine
Cyclosporine is a second line therapy that impairs function of T cells and blunts the immune response. It can take a week to a month to fully work. Atopica has the highest bioavailability in dogs and cats. Only use the microemulsion forms and be careful with human generics (their concentrations may not be high enough)
side effects of cyclosporine
- primarily GI
- gingival hyperplasia, hypertrichosis, excessive shedding, papillomatosis, opportunistic infections
- Idiosyncratic hepatotoxicity
- hepatotoxicity, nephrotoxicity
NOT Myelosuppressive
Chlorambucil is more commonly used in __ because they can’t be given azathioprine
cats!
Chlorambucil is an __ agent that causes __ in dogs but is useful in __ . It has a __ onset of action and __ dosing works best. Side effects include GI, Myelosupression, __ (poodles) and neuro signs in cats.
Chlorambucil is an alkylating agent that causes PLE in dogs but is useful in cats. It has a slow onset of action and pulse dosing works best. Side effects include GI, myelosupression, alopecia (poodles) and neurologic signs in cats.
Leflunomide can be used as an add on or stand along. It __ lymphocyte proliferation and is generally well tolerated but you should start at __ doses to avoid cytopenias or hepatotoxicity. Side effects include GI (inapp/vomit), __ , cutaneous drug reactions and __.
Leflunomide can be used as an add on or stand along. It decreases lymphocyte proliferation and is generally well tolerated but you should start at low doses to avoid cytopenias or hepatotoxicity. Side effects include GI (inapp/vomit), myelosuppression, cutaneous drug reactions and hepatotoxicity.
Lefluonmide should be monitored with a __ and __
CBC and Chem (ALT)
Mycophenolate Mofetil is similar to __ and can be used alone in __ disease or with pred. This is a good option for __ dogs. It can take __ weeks to start working with __ signs as a common side effect.
Mycophenolate Mofetil is similar to azathioprine and can be used alone in stable disease or with pred. This is a good option for large dogs. It can take 2-4 weeks to start working with GI signs as a common side effect.
More commonly, Cyclosporine is used for __ dogs while Mycophenolate mofetil is used for __ dogs
More commonly, Cyclosporine is used for smaller dogs while Mycophenolate mofetil is used for larger dogs
T/F: Human IVIG is used for patients we want to rapidly stop destruction of RBC’s in
T
Human IVIG for IMHA
- short term stabilization
- refractory
- did no reduce transfusion requirements or length of hospitalization
Human IVIG for ITP
- replaces platelet recovery time and length of hospitalization
- did not increase expense compared to prednisone alone
Vincristine
It poisons the platelets and prevents macrophages from eating up RBC’s. This is typically an adjunctive treatment for ITP that helps platelets increase within 3-5 days and shortens hospitalization. It is minimally myelotoxic, but does have neurotoxicity and GI signs.
Thromboprophylaxis
- Antiplatelet therapy with aspirin and clopidogrel (preferred)
- Anticoagulant therapy with heparin
treatment of thromboembolic disease
anticoagulation drugs and factor Xa inhibitors
