Histiocytic Diseases Flashcards
what type of disease is cutaneous histiocytosis?
immune mediated disease
disease of activated interstitial dermal dendritic cells
who is systemic histiocytosis seen in primarily?
familial disease of bernese mountain dogs
what type of cells are in cutaneous histiocytoma?
langerhans cells
what is metastatic histiocytoma classified as?
cutaneous langerhans cell histiocytosis
what does histopathology and cytology of histiocytic sarcoma show?
characteristic multi-nucleate giant cells
what is the origin of feline histiocytic sarcoma?
macrophage
what is a histiocyte?
CD34+ committed stem cell precursors
macrophages
dendritic cells
what do macrophages do?
process and present antigens in association with MHC-II molecules
what do dendritic cells do?
process and present antigens
work with T cells to initiate and immune response
what are langerhans cells?
epidermal dendritic cells
express E-cadherin
what do langrhans cells do?
reside in epidermis
recognize, process, present antigens to T lymphocytes
what are interstitial dendritic cells associated with?
lymphoid tissue
what do cutaneous histiocytosis look like?
multiple non-painful, non-pruritic plaques and nodules
what is systemic histiocytosis like?
like cutaneous histiocytosis but involves mucous membranes, lymphoid organs, and bone marrow
ocular lesions very common
what is survival of systemic histiocytosis?
2-48 months
what is cutaneous and systemic histiocytosis?
disease of disordered immune regulation arising from defective interaction of dendritic cells and T cells
chronic proliferation of dendritic cells and T cells
who is cutaneous histiocytoma seen in?
young dogs
head and feet
what correlates with spontaneous regression of cutaneous histiocytoma?
infiltration of CD8+ cytotoxic T cells
what is metastatic histiocytoma?
widespread epidermal dendritic cell neoplasia
who usually gets solitary histiocytic sarcoma?
flat-coated retrievers
also golden and labrador retrievers
what is solitary histiocytic sarcoma frequently associated with?
joint instability
what is the cell lineage of histiocytic sarcoma?
dendritic cells
what are potential locations of solitary histiocytic sarcoma?
periarticular
pulmonary
spleen
what is disseminated histiocytic sarcoma like?
multiple tumors
aggressive multi-centric disease
which dogs usually get disseminated histiocytic sarcoma?
bernese mountain dogs 25%
rottweilers
what is CCNU/lomustine chemotherapy?
myelosuppressive
oral chemotherapy
what is hemophagocytic histiocytic sarcoma?
diffuse histiocytic infiltration of spleen
what is feline progressive histiocytosis like?
multiple non-pruritic skin lesions
cutaneous form of histiocytic neoplasia
interstitial dendritic cells
slowly progressive
where can feline histiocytic sarcoma be?
spleen
bone marrow
liver
