Flashcards in Histo: Fundamentals of Histology (Emily) Deck (39)
What is the shape of neutrophils?
Polymorphic, multilobulated, lobular nucleus, many granules
2. What type of inflammation are neutrophils important for?
Give examples of pathologies associated with neutrophilic infiltrate.
What cells are key for chronic inflammation?
Lymphocytes and plasma cells
What cancers are associated with high lymphocyte and high neutrophil count respectively?
Chronic infection and Lymphoma = high lymphocytes
Myeloid leukaemia = high neutrophils
What infection may cause high lymphocytes and neutrophils?
What sort of inflammation may be seen in UC and what cells can be seen in the histology of the GIT?
Acute on chronic inflammation may occur. Pt may have acute exacerbations on top of chronic inflammation. Histology may show many plasma cells and lymphocytes, but also many neutrophils in the crypts.
How may you differentiate between inflammation or a lymphoma on histology showing many lymphocytes?
Lymphoma cells all look the same due to clonal differentiation. Inflammation will show mix of cells.
Describe the shape of Eosinophils.
They have granules and bilobed nuclei.
What are Eosinophils associated with?
Tumours e.g. Hodgkin's disease
What is the most common cause of oesophagitis?
What does eosinophilic oesophagitis suggest?
Reflux causes acute inflammation so you would expect neutrophils to be seen on histology. EO suggests an allergic reaction to food that has come in contact with the oesophagus in the same way that asthma is due to allergy to allergens in the air.
Describe what mast cells look like.
Have many granules which contain inflammatory mediators
What sort of allergic reactions are mast cells important for?
Type 1 allergic reactions such as urticaria.
What is the role of macrophages?
Macrophages are cells that clear up the debris following inflammation. Acute inflammation = neutrophil phase. Macrophages come in afterwards. If the inflammation persists and becomes chronic, lymphocytes begin to dominate.
What sort of inflammation are macrophages associated with?
Late acute inflammation
Chronic inflammation (including granulomas)
What is a special type of chronic inflammation associated with macrophages?
What is characteristic of TB histology?
Loads of granulomas. Giant cells are formed by fusion of macrophages. There is necrosis in the middle of granulomas - cheesy necrosis is characteristic of TB
What is a granuloma?
Organized collection of activated macrophages. An organized collection of activated epithelioid macrophages. Epithelioid activated macrophages are involved in secretion of cytokines and they cluster together to form granulomas.
What are causes of granuloma formation?
TB, sarcoid, infectious causes, reaction to tumours
What test is used to confirm TB?
Acid-fast staining (Ziehl-Neelson stain)
Give 4 types of tumours and the cells they are derived from.
Carcinomas = malignant tumours of epithelial cells
Sarcomas = malignant tumours of mesenchymal cells, connective tissue (muscle, bone, cartilage)
Lymphoma = malignant tumours of lymphocytes
Melanoma = malignant tumour of melanocytes
If it ends in sarcoma or carcinoma means it is malignant. Ends in -oma means benign.
What are the 3 main types of carcinomas?
Squamous cell carcinoma
Transitional cell carcinoma
Where are common places for squamous carcinoma?
Skin, head and neck, oesophagus, anus, cervix, vagina
What do squamous cell carcinomas make?
What are adenocarcinomas derived from and where are they found?
Glandular epithelium. These tumours make glands and secrete mucin. Found in the lung, breast, stomach, colon, pancreas.
Where do transitional cell carcinomas occur?
Most commonly in the urinary system, kidneys, ureters, bladder.
What are key histological features of SCC?
High nuclear : cytoplasm ratio
Variable sizes of nuclei
Intercellular bridges (from keratin)
What cells are melanomas derived from?
Melanocytes. Some melanomas become so poorly differentiated that they stop secreting melanoma and become amelanotic melanomas.