Pathology Definitions Flashcards
Define infective endocarditis
Inflammation of the endocardial surface of the heart and valves, due to certain micro-organisms
Define ulcerative colitis
Inflammatory bowel disease affecting the colon in the form of colitis, with characteristic ulcers
Define proto-oncogene
Normal cellular gene whose products promote cell proliferation
Define oncogene
Mutated or over expressed proto-oncogenes, which function autonomously, having lost dependence on normal growth promoting signals
Define tumour suppressor gene
Normal gene whose absence can lead to development of cancer, as they act as gatekeepers which inhibit proliferation, or promote cell death of cells with damaged DNA
Define FAP
Autosomal dominant condition, characterised by loss of APC tumour suppressor gene, leading to development of hundreds of colonic polyps, with 100% risk of cancer by the age of 30yrs
Define endometriosis
Ectopic endometrial tissue outside the uterus
Define dysplasia
Disordered cellular development characterised by increased mitoses and pleomorphism WITHOUT ability to invade the basement membrane
Define abscess
Local collection of pus cells surrounded by fibrous or granulation tissue
May be caused by seeding of pyogenic organisms into a tissue, or secondary infection of necrotic foci
Define pus
Collection of neutrophils with dead or dying micro-organisms
Define ulcer
Lesion of skin or mucous membrane due to gradual disintegration of surface epithelial cells
Define healing by secondary intention
Secondary healing due to re-epithelialisation and contraction
Define giant cell
Multinucleated cells derived from the fusion of multiple activated macrophages to form a granuloma
Define contact tracing
Identification and diagnosis of persons who may have come into contact with an infected person
Define granuloma
Organised collection of macrophages fusing to form langerhans giant cells. Often formed when immune system attempts to wall off substances that it identifies as foreign, but is unable to eliminate
Define ARDS
Acute Respiratory Distress Syndrome
Diffuse alveolar damage + lung capillary endothelial injury
Define malignant melanoma
Malignant neoplasm of melanocytes
Define immune checkpoint inhibitors
Antibodies which interfere with function of proteins on T-lymphocytes, causing cytotoxic T-cell responsiveness. Used to stabilise metastatic disease
Define HER2
Transmembrane epidermal growth factor
Overexpressed in 15% Breast Ca
Associated with bad prognosis
Treated with Herceptin (Trastuzumab)
Define H pylori
Gram negative microaerophilic spiral bacteria found in the stomach
Define frozen section
Pathological laboratory procedure to perform rapid microscopic analysis of a specimen, often intra-operatively
Define crypto-orchidism
Complete or partial failure of the intra-abdominal testes to descend into scrotal sac
Associated with testicular dysfunction and increased risk of ca
Define metastasis
Survival and growth of cells distant from their primary origin
Define choriocarcinoma
Highly metastatic form of testicular ca
Composed of syncytiotrophoblasts and cytotrophoblasts
Tumour marker β-hCG
Define multiple myeloma
Plasma cell neoplasm, associated hypercalcaemia, renal failure, anaemia and lytic bone lesions
Produces large amount of IgA + IgG
Define bence jones proteins
Monoclonal globulin proteins or immunoglobulin light chains found in the urine
Present in 2/3rds of multiple myeloma cases
Define gangrene
Type of necrosis characterised by critically insufficient blood supply
Define necrosis
‘Accidental’ and unregulated cell death resulting to damage to cell membranes and loss of ion homeostasis
Define atherosclerosis
Pathological process of the vasculature, in which artery walls become thickened due to accumulation of fatty materials such as cholesterol
Define thrombus
Solid material formed from the constituents of blood, within flowing blood
Define DIC
Disseminated Intravascular Coagulation
Pathological consumptive coagulopathy
Due to activation of coagulation and fibrinolytic systems
Leading to widespread haemorrhage and formation of micro thrombi in many organs, with the consumption of clotting factors and platelets
Define group cross matching
Testing of donor red cells against recipient serum
To detect incompatibility in which antibodies in recipient cause haemolysis of donor cells
Define hyperplasia
Increase in number of cells in tissue or organ in response to a stimulus
Define two hit hypothesis
Most loss-of function mutations in tumour suppressor genes are RECESSIVE
In order for a cell to become cancerous, BOTH the cells tumour suppressor genes must be mutated
Define telomere
Region of repetitive nucleotide sequences at each end of chromosome, which protects the end of the chromosome from degradation or from fusion with neighbouring chromosome
Define apoptosis
Programmed cell death
Define Mohs micrographic surgery
Serial tangential horizontal sections are taken and examined histologically until all margins are clear
Define pleomorphic
More than one distinct form of a natural object = histological diversity
Define cytology
Study of CELLULAR structure and function
Define histology
Study of TISSUE under a microscope
Define sequestrum
A piece of dead bone that has become separated from surrounding bone, during process of necrosis
Sequelae of osteomyelitis
Define involucrum
Reactive lamellar bone depositions forming shell of living tissue around sequestrum
Define haemolysis
Rupture/lysis of RBCs and release of their contents into surrounding fluid
Define Barrett’s oesophagus
Metaplasia of stratified squamous oesophageal epithelia to gastric columnar epithelia
Define troponin
Complex of 3 regulatory proteins (Trop C, I, T) that is integral to muscle contraction
Cardiac and skeletal muscle
Define IHC
Immunohistochemistry
Method of localising specific antigens in tissues or cells based on antigen-antibody recognition
Antibodies linked to enzyme or fluorescent dye
Define carcinoma
Type of cancer originating in epithelial cells
Define melanosis coli
Disorder of pigmentation of the wall of the colon
Benign, may have no significant correlation with disease
Define adenoma
Benign tumour formed from glandular structures in epithelial tissue
Define haemorrhoids
Swollen or inflamed anal cushions
Define cellulitis
Spreading bacterial infection of the skin affecting the dermis and subcutaneous fat
Characterised by warmth, swelling, pain and erythema
Define GIST
Gastrointestinal Stromal Tumour
Most common mesenchymal tumour of abdomen, usually in stomach
Arise from benign pacemaker cells (interstitial cells of Cajal)
Due to mutation in tyrosine kinase cKIT oncogene and PDGFRA (platelet derived growth factor receptor α)
Define CD117
cKIT
Transmembrane tyrosine kinase receptor
Marker of GIST
Define adenocarcinoma
Malignant tumour formed from glandular tissue in epithelial tissue
Define emphysema
Abnormal permanent enlargement of air spaces distal to terminal bronchioles
Destruction of alveolar walls
WITHOUT obvious fibrosis
Define HCV
Hepatitis C
Infectious disease caused by hepatitis C virus, primarily affecting the liver
Define retrovirus
Type of virus that inserts a copy of its RNA genome into the DNA of its host cell that it invades, changing the genome of that cell
