Immune-mediated diseases Flashcards
Pemphigus complex, vasculitis, histiocytic, lupus, EM, SJS/TEN
What is the most common antigen targeted in human PF?
Desmoglein-1
What is the most common antigen targeted in canine PF?
Desmocollin-1
What is the most common antibody isotype in canine and human PF?
IgG
What 4 insecticides have been implicated as a trigger in PF?
Metaflumizone-amitraz (Promeris)
Fipronil-amitraz-S-methoprene (Certifect)
Dinotefuran-pyriproxyfen-pyrethrin (Vectra 3D)
Afoxolaner (Nexgard)
What is the name of the endemic form of PF and where is it endemic?
Fogo selvagem, Brazil
What is the pathogenesis of fogo selvagem?
Sand fly salivary antigen LJM11
sand fly bites human –> antigen cross-reacts with Dsg-1 –> trigger PF
What are the 4 phenotypes of canine PF?
Facial-dominant
Truncal-dominant
Generalized
Foot pad-exclusive
What are two primary differentials for PF?
pustular dermatophytosis (Trichophyton)
superficial pyoderma
What is the antigen targeted in the mucosal-dominant variant of human PV?
Desmoglein-3
What is the antigen targeted in the mucocutaneous variant of human PV?
Desmoglein-1 and desmoglein-3
What is the antigen targeted in canine PV?
Desmoglein-3 (and less Dsg-1)
Histopathology of canine skin lesions reveals suprabasal keratinocyte acantholysis with basal cells remaining attached at the basement membrane, resembling tombstones. Which autoimmune disease is most likely?
PV
What desmosome is more prevalent in mucosa?
Dsg-3
What are the 3 types of deep pemphigus?
PV
Pemphigus vegetans
Paraneoplastic pemphigus
Besides anti-DSG3 antibodies, what other gene is suspected to be involved in canine PV?
c-Myc
What gender is more commonly affected by canine PV?
Males (opposite of human PV)
True or false: Pruritus is common in canine PV
False
What is the best area to biopsy for diagnosis of PV?
Margin of an erosion/ulcer (1/3 lesional skin, 2/3 perilesional skin)
What is the most common distribution of human Pveg?
Periorificial and intertriginous areas
Describe the Neumann-type vs. the Hallopeau-type of Pveg in humans
Neumann-type: starts with vesicles/blisters
Hallopeau-type: starts with pustules
What are the histopathologic features of Pveg?
PV (suprabasilar acantholysis) + hyperplastic PF
What subtype of human Pveg has a better prognosis?
Hallopeau-type
What neoplastic conditions have been associated with paraneoplastic pemphigus in dogs and cats?
Thymoma
Thymic lymphoma
Splenic sarcoma
What are the most consistent targets of paraneoplastic pemphigus?
Periplakin
Envoplakin
Desmoglein-3