MSK Flashcards
What is the accepted definition of suppurative inflammation in synovial fluid?
Nucleated cell count > 2 cells/hpf
Neutrophil counts >10-12%
What are the 3 types of arthritis
Degenerate
Immune mediated
Infective
Does a normal joint sample have low or high values of the following:
Total cell count
% of mononuclear cells
% of neutrophils
Low total cell count
High % of mononuclear cells
Low % of neutrophils
If you have a joint tap that is highly cellular with 1% monocytes and 99% neutrophils, what diease are you most concerned about
Infective arthritis
What is the dominant cytokine in human rheumatoid arthritis
TNF alpha
What is the general pathophysiology that occurs in IMPA
Antigen forms and causes a normal immune response
Phagocytosis of immune complexes
Persistent antigenic stimulation OR problem in normal down regulation of immune system
What is the most common cause of IMPA
Idiopathic
What dog gene has been associated with canine IMPA
DLA-DRB1
(DLA = dog leukocyte antigen)
Is it typically for dogs with IMPA to have one or multiple joints affected?
Multiple
When making a diagnosis of IMPA, how many joints should be sampled
At least 3
What is the main differential for IMPA prior to cytology results?
Infective arthritis
What other test could be pursued if you are unable to obtain enough synovial fluid for diagnosis
Synovial biopsy
True/False: Canine rheumatoid factor assays are specific for canine RA
No, the Rh factors can show up with any chronic inflammatory condition
What is type 1 IMPA
Idiopathic
What is type 2 IMPA
Infection remote from the joint
What is type 3 IMPA
Associated with GI disease
What is type 4 IMPA
Paraneoplastic
What types of cancer have been reported in dogs with IMPA TYPE 4
Seminoma
Mammary carcinoma
Renal carcinoma
Tonsillar carcinoma
Sertoli cell tumor
Leiomyoma
What immune suppressive medication has been well studied in polyarthritis on dogs/cats?
Leflunomide
What is the reported response rate for IMPA?
Relapse rate?
56%
1/3rd
What is systemic lupus erythematosus
A multisystem immune mediated disorder associated with the appearance of antinuclear antibodies
What are “major” signs of SLE?
Skin lesions
Polyarthritis
Hemolytic anemia
Glomerulonephrotis
Proteinuria
Polymyositis
Leukopenia
Thrombocytopenia
What are “minor” signs of SLE?
Pyrexia w/ CNS signs
Oral ulceration
Lymphadenopathy
Pericarditis
Pleuritis
What is a definite diagnosis of SLE based on?
2 major signs
Or
ANA > 160, 1 major and 2 minor
What breeds have been reported to have specific forms of breed associated IMPA
Chinese shar pei
Japanese Akita
What is the main difference between IMPA and rheumatoid arthritis on dogs?
IMPA is non-erosive; RA is erosive
Three causes of bacterial infective arthritis
Hematogenous
Penetration
Spread from local tissues
Common bacterial causes of septic arthritis
Dogs:
Staphylococcus
Strep
Cats:
Pasteurella
Bacteroides
What are the two types of post op infective arthritis infections?
Type 1 - acute
Type 2 - delayed/chronic (6-24 mo after SX)
Most common antibiotics used for infective arthritis
Clavamox
Cephalexin
+/- metro
What are 3 juvenile ortho diseases
HOD
CMO
Panosteitis
Describe the radiographic appearance of HOD
Radiolucent line parallel to the physis in the long bone metaphysis (severe cases, metaphyseal flare)
Describe the radiographic appearance of HO
Pallisade periosteal reaction on long bones
What is HO associated with
Neoplasia (most commonly pulmonary carcinoma)
Age range for panosteitis
6-12 mo
Age range for HOD
2-6 mo
Radiographic appearance of CMO
Unilateral or bilateral symmetric irregular bone proliferation of caudal mandible, ramus, +/- bulla
Breed most commonly seen with HOD
Weimeriners
Type 1 salter harris fracture
The epiphysis separates from the rest of the long bone
Type 2 salter Harris
breaks at an angle, cutting through most of the growth plate and the metaphysis
Type 3 saltar harris fracture
Segment of epiphysis breaks off
Type 4 saltar harris fracture
Runs vertically through the growth plate, segment of metaphysis and epiphysis (eg like a corner breaks off, think tibia)
Type 5 saltar harris
Compression of growth plate
