Immune-Mediated and Autoimmune Diseases Flashcards
what are the autoimmune diseases?
pemphigus
pemphigoids
lupus erythematosus
what are the types of pemphigus?
pemphigus foliaceus
pamphigus erythematosus
pemphigus vulgaris
paraneoplastic pemphigus
what three protein types do desmosomes have?
plakins
armadillo proteins
cadherins
what is the pathogenesis of pemphigus foliaceus?
IgG autoantibodies to desmocollin-1 in 75%
what is the most common autoimmune disease?
pemphigus foliaceus
which dogs may be predisposed to pemphigus foliaceus?
chow chow
akitas
what are the etiologies of pemphigus foliaceus?
spontaneous most common
can be drug-induced/triggered
can be disease-induced/associated?
what is the major autoantigen in dogs with pemphigus foliaceus?
desmocollin-1
what is the primary type of lesion in pemphigus foliaceus?
pustule
what are the most common and early affected areas in pemphigus foliaceus?
pinnae
head and face
nasal planum
cats: claw folds
cats: skin around nipples
footpads
what is the primary differential diagnosis with pemphigus foliaceus?
pyoderma
what is the history like with pemphigus foliaceus?
non pruritic pustules/crusts
pruritus in 31-73% of feline cases
where should you collect samples for cytology in pemphigus foliaceus?
intact pustule: best
under superficial crust
from claw fold pus
what is the goal in the induction phase of treating pemphigus foliaceus?
suppress immune system enough for lesions to stop spreading and start healing
1-8 weeks
what is the pulse therapy for pemphigus foliaceus in dogs?
10 mg/kg SID prednisone or prednisolone for 3 days, then 1 mg/kg SID
what are the drug options for pemphigus foliaceus in the induction phase for cats?
prednisolone
triamcinolone
prednisolone and chlorambucil
prednisolone and cyclosporine
oclacitinib
what should you do with drugs in the maintenance phase of pemphigus foliaceus?
decrease does of predniso(lo)ne, every other day, withdraw slowly if possible
decreases doses of other drugs
consider topical if lesions are few
what is pemphigus vulgaris?
very rare, very severe vesicular and ulcerative disease
affects mucus membranes and haired skin
what are pemphigoids?
bullae and clefts between dermis and epidermis
autoimmune subepidermal blistering diseases
what is a skin biopsy for in pemphigoid?
necessary for confirmation
cannot differentiate one pemphigoid from another
what do lymphocytes do in lupus erythematosus?
damage basal cells: basal keratinocyte apoptosis
what lesions are primarily seen in facial discoid lupus?
depigmentation
erythema
scales
loss of nasal planum architecture
what should you rule out with facial discoid lupus?
mucocutaneous pyoderma
who has a genetic predisposition to uveodermatologic syndrome?
akitas
samoyeds and huskies also
what happens in uveodermatologic syndrome?
autoimmune attack to melanocytes or melanocyte-associated antigens
what are the skin lesions like in uveodermatologic syndrome?
always face (nose) or head
depigmentation
erosions, ulcers
what is needed for diagnosis of uveodermatologic syndrome?
clinical presentation and breed
histological examination
what is the prognosis of uveodermatologic syndrome?
cautious: lifetime treatment may be required, changes in eyes may be irreversible, no spontaneous remission
how is uveodermatologic syndrome treated?
systemic aggressive immunosuppressive treatment: predniso(lo)ne or predniso(lo)ne with azathioprine or cyclosporine
topical eye treatment
what dogs are predisposed to canine perianal fistulas/anal furunculosis?
german shepherd dogs
middle-aged
are canine perianal fistulas/anal furunculosis related to anal sacs?
no
what are the clinical signs with canine perianal fistulas?
painful defecation
bloody discharge
tenesmus
painful while manipulating/getting cleaned
odor
is surgical management effective for canine perianal fistulas?
no
what is the main treatment for canine perianal fistulas?
cyclosporine
what are the other names for juvenile cellulitis?
sterile granulomatous dermatitis and lymphadenitis
puppy strangles
what are the clinical signs of juvenile cellulitis?
deep papules, pustules, nodules, draining tracts
lymphadenitis, abscesses
purulent otitis
joint pain/lameness
fever
how can juvenile cellulitis be treated?
prednisone 2mg/kg SID
wait with vaccination
systemic antibiotics only if cytology shows secondary infection
what is lupoid onychodystrophy/symmetrical idiopathic onychomadesis like?
nail/nailbeds inflammation: dystrophy and sloughing of nails
syndrome, not single diagnosis
what is the treatment for lupoid onychodystrophy?
fish oil
doxycycline and niacinamide
cyclosporine
steroids
pentoxifylline
apoquel?
nail removal
3rd phalanges amputation
where are ischemic skin lesions due to vasculitis seen?
ear pinnae
footpads
tip of tail
how can vasculitis be managed?
pentoxifylline
cyclosporine/tacrolimus
sulfasalazine
steroids
oclacitinib
what is the etiology of feline plasma cell pododermatitis?
unknown
likely infectious or immune-mediated
no viral, bacterial, or allergic components found
what is seen on cytology of feline plasma cell pododermatitis?
plasma cell predominating
what are the early signs of feline plasma cell pododermatitis?
scaling of footpads
softness
within each protein group in desmosomes, when do amounts of particular proteins differ?
depending on layer and body area
in what percentage of dogs with pemphigus foliaceus with high IgG autoantibodies in desmocollin-1 did those titers lower with clinical improvement?
70%
which cats are predisposed to pemphigus foliaceus?
no sex or breed predisposition
DSH, DLH, siamese overrepresented
females slightly
what diseases in cats can cause pemphigus foliaceus?
thymoma
leishmaniosis
what is the main clinical presentation of pemphigus foliaceus?
crust
can pemphigus foliaceus be generalized and have systemic signs?
yes
what can be seen on cytology with pemphigus foliaceus?
non degenerative neutrophils
acantholytic cells
how can you treat pemphigus foliaceus in cats?
prednisolone
triamcinolone
prednisolone and chlorambucil
prednisolone and cyclosporine
oclacitinib/apoquel
what does the prognosis of pemphigus foliaceus depend on?
severity of clinical presentation and necessity of systemic treatment
response to initial treatment
possibility to taper or withdraw medications
presence of adverse side effects
what is pemphigus erythematosus like?
“combination” of pemphigus foliaceus and facial discoid lupus
mostly pustular and crusted disease
what are the types of pemphigoids?
mucous membrane pemphigoid
bullous pemphigoid
epidermolysis bullosa acquisita
what happens in lupus erythematosus?
UV-sensitivity
basal cells damage by lymphocytes- basal keratinocyte apoptosis
lymphocytic/histiocytic dermal infiltration
autoantibodies to nuclei and/or cytoplasmic antigens
immune complexes deposition along basal membrane
what is facial discoid lupus erythematosus like?
no systemic signs
photosensitivity in 50%
infiltration of skin mainly by plasma cells
what breeds are predisposed to facial discoid lupus?
german shepherds
collies
huskies
german pointers
what is the prognosis of facial discoid lupus?
good, but life-long treatment often
is there a sex predilection for uveodermatologic syndrome?
yes- males>females
where are skin lesions in uveodermatologic syndrome?
always on face/nose or head
depigmentation
erosions, ulcers
what is canine perianal fistulas/anal furunculosis?
painful sinuses around anus
not related to anal sacs
how can you diagnose canine perianal fistulas?
mostly clinical
histological changes not specific
what can be used in mild cases of canine perianal fistulas?
tacrolimus topically
how can you diagnose juvenile cellulitis?
unique presentation, some breeds
negative skin scrapings for demodicosis
cytology: sterile pyogranulomatous inflammation
adult: skin biopsy
why should you biopsy thee 3rd phalange in lupoid onychodystrophy?
rule out other diseases
not very specific histological changes
what is the prognosis of lupoid onychodystrophy?
not predictable response to treatment
partial response common
life-long usually
aggressive therapy not always
what is the usual cause of vasculitis in dogs?
idiopathic
what are the later signs of plasma cell pododermatitis?
dark color of deeper tissue
eventual ulceration
how can you treat plasma cell pododermatitis?
doxycycline and niacinamide
prednisolone
cyclosporine
surgical excision
