Pathology of Connective tissues Flashcards
What are the primary functions of connective tissue?
- Provide structural support
- Serve as a medium for exchange
- Aid in the defence and protection of the body
- Form a site for storage of fat
- Provide a matrix that connects and binds cells and organs
- Insulation
Why is the study of connective tissue important?
- Proteins are a normal constituent of tissue
- Raised or depleted amounts of specific proteins
- Inappropriate deposition of normal proteins
- Deposition of pathological proteins
List the types of connective tissue classification.
Connective Tissue proper
* Loose connective tissue
* Dense connective tissue (regular and irregular)
Connective tissues with special properties
* Adipose CT
* Elastic CT
* Hematopoietic CT
* Mucous CT
Supporting connective tissue
* Cartilage
* Bone
What are the cellular components of connective tissue?
- Fibroblasts
- Myofibroblasts
- Adipocytes
- Chondrocytes
- Osteocytes
- Immune cells (macrophages/histiocytes, mast cells, lymphocytes, plasma cells)
- Endothelia
- Blood and lymph vessels
What is the composition of the extracellular matrix (ECM)?
- Ground substances
- Fibres (collagen, elastic, reticular fibres)
- Gel matrix (glycoproteins, mucins, water)
What can excess accumulation in tissue/organ lead to?
- Fibrosis and scarring
- Scleroderma
- Genetic disorders (e.g., Osteogenesis imperfecta, Epidermolysis bullosa, Alports syndrome)
- Vitamin deficiency (Scurvy)
What are the symptoms of scleroderma?
- Excessive collagen in skin and organs
- Tight skin
- Sensitivity to cold
- Digestive problems
- Hardening of connective tissue
What role do reticulin fibres play in connective tissue?
- Provide bulk of the supporting framework in more cellular organs (e.g., spleen, liver)
- Arranged in a 3D network for individual cell support
What is the basement membrane and its functions?
- 3D complex of proteins and carbohydrates
- Provides support to epithelial cells, muscles, and peripheral nerves
- Permits diffusion of nutrients and wastes between cells and capillaries
True or False: Cancers are termed in situ if they have invaded the basement membrane.
False
What are the components of elastic fibres?
- Elastin
- Microfibrillar proteins
- Fine fibres and thick laminae
What are the characteristics of benign tumours in connective tissue?
- Slow-growing
- Easy to remove
- Typically named with the suffix ‘oma’
What is liposarcoma?
- Most common soft tissue sarcoma of adults
- Usually found in deep soft tissue
- Tumour size and histologic classification are important prognostic factors
What distinguishes cartilage from bone?
- Cartilage is acid mucin rich
- Bone has osteoid that is calcified
What is the process of decalcification in bone processing?
- Dissolving calcium salts using weak and strong acids or calcium chelation by EDTA
List some metabolic bone diseases.
- Osteoporosis
- Osteomalacia
What is osteosarcoma?
- Tumour that produces osteoid
- Mainly occurs in long bones
- Common in ages 10-25 years and over 40 years
What is a key diagnostic feature of Ewing’s sarcoma?
- Small round blue cells
- Chromosomal translocation with EWS gene
What is multiple myeloma characterized by?
- Ig excess in blood
- Presence of Bence Jones protein in urine
- Increase in abnormal plasma cells in marrow and blood
