Systemic Lupus & Immune Mediated Polyarthropathies Flashcards
What are the most commonly reported manifestations for SLE?
- Polyarthropathy (pain in multiple joints)
- Skin lesions (mucocutaneous jxn)
- Renal GLN or PLN
- Blood dyscrasia
(must have atleast 2 to say its SLE)
What dog breeds are slightly more overrepresented with SLE?
- GSD
- Sheltie
- Collies
- Poodles
How can SLE be definitely diagnosed?
- Positive anti-nuclear antibody (ANA) test from serum with at least 2 body systems affected
(Renal GLN or PLN, IMPA, immune mediated skin disease, IMHA, etc)
What is the treatment protocol for SLE?
- Prednisone
- Azathioprine
- Levamisole? (sheep dewormer)
What is the prognosis of SLE?
- Guarded, relapses occur
- Long term therapy with Pred +/- Azathioprine, months or longer is needed
What are non inflammatory causes of polyarthropathy?
- Osteoarthritis / DJD
- Traumatic injury
(would see mononuclear plasma cells and macs in synovial fluid)
What are inflammatory causes of polyarthropathy?
- Infectious (septic joint)
- Rheumatoid arthritis (erosive IMPA)
- Non erosive IMPA
List non erosive causes of IMPA
- Idiopathic (Primary IMPA) most common
- Type II: secondary to infection elsewhere (UTI, endocarditis)
- Type III: Hepatic / GI associated
- Type IV: Distant neoplasia
- Misc tick borne disease, vaccine induced, drug induced, SLE
What are the most suggestive exam findings for Idiopathic/Primary IMPA?
- Lameness/gait abnormalities
- Fever
- Joint pain and swelling affecting multiple limbs
How would you work up a middle age dog presenting with multiple limb lameness and evidence of joint pain and swelling on PE?
- CBC, Chem, UA
- Rads
- Arthrocentesis of multiple joints for direct smear, cell counts, and bacterial culture of synovial fluid
- 4DX for tick borne dz
What is seen in synovial fluid with IMPA?
- Non degenerate neutrophils
- Increased NCC > 3000
(Good diagnostic for IMPA but doesn’t determine the underlying cause)
What is seen in synovial fluid with osteoarthritis / DJD?
- Mononuclear plasma cells and macs (Reactive joint)
(No neuts!!! Use arthrocentesis of synovial fluid to differentiate IMPA vs Rheumatoid Arthritis vs Reactive joint disease)
What is the treatment protocol for a patient diagnosed with Primary IMPA
- Prednisone at immunosuppressive dose of 2mg/kg/day
- Repeat arthrocentesis q 2-3 weeks
- +/- Azathioprine, cyclosporine, etc
- Some cases meds can be tapered off
What is the treatment protocol for a patient diagnosed with Secondary IMPA?
- Short term NSAIDs and Doxy for Tick borne disease
- Short term NSAIDs for drug/vaccine induced which resolves quickly
- Treat neoplasia if IMPA secondary to LSA, OSA, HSA
What neoplasia can cause secondary IMPA?
- LSA
- OSA
- HSA