Autoimmune skin disease characterized by formation of subcorneal pustules due to acantholysis
what is acantholysis? What is the result of it?
Attack and destruction of intercellular bridges (desmosomes) resulting in intraepithelial blister formation
what is the autoimmune mechanism behind pemphigus folicaeus?
IgG autoantibodies against desmosomal proteins
what do the pustules from pemphigus folicaeus contain?
Pustules contain acantholytic cells and variable numbers of neutrophils
which desmosome is attacked in dogs?
desmocollin-I (Dsc-1) (humans is desmoglein-I (Dsg-1) )
how common is PF?
Most common canine autoimmune skin disease
which breeds are predisposed to PF?
Akita, Chow Chow (but any breed can be affected)
is it young dogs or adult dogs who get PF?
Adult dogs (4-8 years) (but still can affect any age. she mentioned it can affect cats too)
does PF cause pruritus?
Pruritus moderate to absent
what dz can PF mimic to confuse you?
Can mimic bacterial folliculitis*
Three main clinical presentations (lesions) of PF?
(1) Papules, pustules, collarettes, crusts (yellowish); generalized distribution (2) Depigmentation, erosions, ulcers, crusts on planum nasale, dorsal muzzle, pinnae, periocular skin (3) Footpad hyperkeratosis, crusting (A patient can present with 1, 2 or 3 or any combination of the above)
PF can look like things that cause folliculitis...which 3 things cause folliculitis?
demodex + bacterial foliculitis + dermatophytosis
PF can be big pustules, what is the other problem that causes large pustules?
bacterial infxn (pic is PF)
can cats get PF?
what are the lesion distributions for FELINE PF?
"stripper dz" because lesions on face, nipples, and nails
how do you dx PF? (2) (what sample sites?)
(1) Cytological examination (intact vesicles-pustules, under crusts) to find acantholytic cells (she says she wont just use cytology to dx- need bx too) (2) Multiple biopsies (pustules) for histopathologic examination
what are acantholytic cells? What do they look like?
these are keratinocytes which are immature and more superficial than they should be due to the desmosomes being attacked so they are in places they shouldn't be. look like "fried eggs"
what are the three drug types/drugs you give to tx PF?
(1) Prednisone or prednisolone (2 mg/kg PO, q 24h) (she said some books will say up to 10, but she says this is too high stick to 2) (2) +/- Azathioprine (1.5-2 mg/kg PO q 24h) (never in cats!!!) (3) Antibiotics for secondary infections
how do you go about GIVING tx for PF? (phases)
In two phases: (1) Induction (high-dose daily) 2 weeks (2) Maintenance (low-dose EOD--> every other day/ETD-->??) for life long
which drug can you give to tx PF that you can give to dogs but NOT CATS?
what does CBC, serum chemistry look like for a dog with SND?
Normochromic, normocytic, non-regen anemia, Hyperglycemia, Elevations in ALP, AST; Hypoalbuminemia, Increased postprandial bile acids
what will amino acid levels be like with SND?
Hypoaminoacidemia (makes sense, dz is bc liver problem--> cant make certain amino acids)
what two things are you gonna look at with abdominal U/S, and what will you see in SND?
(1) Liver disease: “honeycomb” or “Swiss cheese” pattern (2) Pancreatic disease: rare, tumor detected on US
what does SND look like on histopath?
Very specific changes!!!!: (1) Epidermal hyperplasia with marked parakeratosis (4 diamonds) (2) Vacuolar degeneration in middle layer of epidermis (star) (3) Moderate inflammatory infiltrate in dermis (one diamond)
what does the "red" mean in the red white and blue histo pattern? where is it?
Red at the most superficial point--> This is the epi hyperplasia with parakeratosis (Parakeratosis is a mode of keratinization characterized by the retention of nuclei in the stratum corneum)
what does the "white" mean in the red white and blue histo pattern? where is it?
white in the middle of red and blue--> this is Vacuolar degeneration
what does the "blue" mean in the red white and blue histo pattern? where is it?
most deep layer- these are inflammatory cells
what is the treatment for SND, what should you know about it?
SND is a marker for a serious internal disease with a short survival time; poor prognosis (aprx 6 months from the time of diagnosis). If glucagonoma, surgery is indicated. Amino acid solutions can be given IV as supportive therapy to patients with liver disease and hypoaminoacidemia
what is ETCL a neoplasia of, what is going on with it?
Neoplasia of T lymphocytes that infiltrate the epidermis & mucosal epithelium (epitheliotropism)
age disposition for ETCL?
what are lesions of ETCL?
Ulcerative stomatitis, nasal depigmentation, erythematous plaques, scales, variable pruritus, nodules, erosions, ulcers (in pic you can see hypopigmentation and loss of architecure, ie smooth not cobblestone, on nose)
how do you dx ETCL?
Diagnosis by multiple biopsies and histopathology
what are the neoplastic lymphocytes doing, and what problems do they cause?
Neoplastic lymphocytes invading the epidermis, often with destruction of hair follicles and adnexae
what does histopath look like for ETCL?
see tons of neoplastic lymphocytes invading the skin (all those purple dots are lymphocytes)
how do you tx ETCL?
No effective treatment (Lomustine, prednisone)
prog of ETCL?
Poor prognosis...about 6mo at time of dx
(1) Nose erosions, ulcers, depigmentation (2) Mucosal erosions, ulcerations (3) Footpad hyperkeratosis, fissures, ulcers--> does DLE have any, some, or all of these?
1 and 2
(1) Nose erosions, ulcers, depigmentation (2) Mucosal erosions, ulcerations (3) Footpad hyperkeratosis, fissures, ulcers--> does PF have any, some, or all of these?
1 and 3
(1) Nose erosions, ulcers, depigmentation (2) Mucosal erosions, ulcerations (3) Footpad hyperkeratosis, fissures, ulcers--> does SND have any, some, or all of these?
(1) Nose erosions, ulcers, depigmentation (2) Mucosal erosions, ulcerations (3) Footpad hyperkeratosis, fissures, ulcers--> does ETCL have any, some, or all of these?