Final Exam: immune deficiency - malignant bone tumor Flashcards
B cell deficiency increases susceptibility to _______; while T lymphocytes increase susceptibility to _________
Bcell = Bacterial infection
TLymph =Viral and fungal infections
A specialized protein in the blood usually formed in response to antigen
Antibody
An agent which initiates production of specific antibodies against itself
Antigen
An agent which alone is not antigenic but exhibits antigenic properties when attached to other protein molecules
Haptens
Type 1 hypersensitivity is
- Anaphylactic
- Mediated by IgE bound to mast cells and basophils
- Results in rapid release of histamine
What are examples of local type 1 hypersensitivity reactions (3)?
Hay fever, food allergies, skin reactions
What are examples of systemic type 1 hypersensitivity reactions (2)?
Widespread vasodilation
Bronchospasm
Type 2 hypersensitivity
- antibodies directed toward antigens located on cell surfaces or in ECM
Antibody dependent mechanisms of Type II hypersensitivity (3)
- Complement mediated mechanisms: lysis of target cell, opsonization, phagocytosis e.g. transfusion or drug reactions
- Antibody dependent cytotoxicity: NK cells target tissue elements with bound antibody
- Antireceptor antibodies: non-cytotoxic mechanisms, antibodies activate or block cell membrane receptors e.g. Graves’ disease — antibodies mimic TSH; myasthenia gravis — antibodies block ACh receptors
Graves’ disease
antibodies mimic TSH
Myasthenia gravis
antibodies block ACh receptors
Type 3 hypersensitivity
Is an immune complex injury
Immune complex
Antigen and antibody that form in blood and tissue fluids
Activate complement and elicit inflammatory responses and tissue damage
What is the type 3 hypersensitivity that is:
Formation of circulating immune complexes in sensitized host
Serum sickness
**What is the type 3 hypersensitivity that is:
Multiple autoantibodies contribute to injury of various structures
Systemic lupus erythematosus (SLE)
**What is the type 3 hypersensitivity that is:
Associated with local immune complex injury
Arthus reaction
Type 4 hypersensitivity
Delayed hypersensitivity
Sell mediated, especially T-lymphocytes. Skin rashes in certain virus infections and in contact dermatitis, and granulomatous diseases
Example of type 4 hypersensitivity (3)
Tuberculosis
Leprosy
Acute rheumatic fever
A system of cell surface proteins know as major histocompatability (MHC) antigens
Human leukocyte antigens (HLA)
MHC gene products are grouped into 3 classes:
Class I: presented on nucleated cells and platelets
Class I & II associated with antigen presenting and production of cell surface glycoproteins
Class III: genes are associated with complement
HLA-B27
90X greater chance of developing ankylosing spondylitis
Note: HLA-DR3/4 = type 1 diabetes
Chronic multisystem inflammatory disease that commonly affects skin, kidneys, serosal membranes, joints, heart, CNS
Systemic lupus erythematosus (SLE)
***Classic triad of SLE
Butterfly rash
Joint pain
Fever
***Endocarditis is characterized by
patchy vegetation’s on exposed surfaces of valves
***What are (6) environmental risk factors for SLE?
UV light Drugs Psoralens (figs, parsnips) Estrogen (e.g. pregnancy) Viruses Stress
***How do you diagnose lupus?
ANA: Antinuclear antibodies to double stranded DNA and smith antigens
Note: Serum ANA levels correlate with severity of disease.
Note #2: ANA is sometimes present in non-SLE population too.
SLE heart problems include
Pericarditis
Myocarditis
***Endocarditis: patchy vegetation’s on exposed surfaces of valves
Overproduction of collagen throughout the body
Scleroderma
**Describe diffuse and localized patterns of scleroderma
Diffuse: early widespread skin involvement with rapid progression and visceral effects (ANA)
Localized: only skin of face and fingers. CREST syndrome (calcinosis, raynaud’s phenom, esophageal dysfunction, sclerodactyly, telangiectasias)
What is CREST syndrome?
Combined effects known of localized scleroderma:
- Calcinosis — calcific deposits
- Raynaud’s phenomenon — CT disorders fingers and toes turn cyanotic and whitish
- Esophageal dysfunction — scarring around esophagus
- Sclerodactyly - shortening digits
- Telangiectasias - micro exposed BV on face (ecchymosis)
What is the differentiating factor between polymyositis and myasthenia gravis?
Polymyositis spaces the extra-ocular muscles
What 6 organs are affected in scleroderma?
Skin GI tract Musculoskeletal Kidneys Lungs Heart
Polymyositis is
Inflammatory damages to skeletal m — groups of muscles degenerate
What are the 3 factors of dermatomyositis (which is polymyositis + skin issues)
Butterfly rash
Helicotrope eyelids
Purple bumps on knuckles
4 questions in 1:
What is the 1˚ cause of osteoporosis (2)?
What is the 2˚ cause of osteoporosis (4)?
Do they present differently?
Do you see serum changes?
1˚ Being an old female (menopausal)
2˚ diet/lifestyle, preggo, vitamin D deficiency, endocrine disorders
No, 1˚ and 2˚ present the same way.
No serum changes: composition the same, quantity decreased.
What does osteoporotic bone look like (3)?
Catfish vertebra
Schmorl’s nodes
Vertebral collapse (dowager hump)
What is Osteomalacia associated with and why?
Poor calcification of bone matrix; vitamin D deficiency usually
What serum changes will you notice with osteomalacia?
Low calcium, low phosphate, HIGH alkaline posphatase
Looser’s zones associated with
Osteomalacia “soft bones”
Looser’s zones are pseudofractures
Osteomalacia for young people is called?
Rickets (juvenile osteomalacia)
Rickets (juvenile osteomalacia) is associated with skeletal deformities (4)
- Rachitic rosary
- “Pigeon breast”
- Harrison’s groove
- Craniotabes
Ostoemyelitis is associated with what bone deformity?
Brodie’s abscess: common in tibia
Infection of marrow and bone
Osteomyelitis
Pyogenic osteomyelitis vs tuberculous osteomyelitis
Pyogenic — infection of hematogenous origin
Tuberculous — Pulmonary Tb can lead to lesions of bone and if its in the spine its Pott’s Disease
Von recklinghausen’s disease of bone is associated with what disease
Hyperparathyroidism.
Less common now because people are being treated
Characteristics of Von recklinghausen’s disease of bone (2)?
- moth eaten x-ray
- brown tumors
*not all inclusive
Paget’s disease (osteitis deformans) is what kind of bone disease and how does it present?
Hyperosteolytic bone disease; thick + porous
Histologically Paget’s disease
Tile-like mosaic
Bone scan for Paget’s disease shows
Increased activity (hyperosteolytic)
Monostotic lesions versus polyostotic lesions in Paget’s disease
Mono: tibia - 15% of cases
Poly: multiple sites - 85% of cases
Stages of Paget’s disease progression (3)
- Hot (osteoclastic phase)
- Mixed (osteolytic, osteoblastic)
- Cold (burned out stage)
2˚ metastatic cancer is ___% more common that 1˚ bone tumors.
70%
___% of metastatic bone disease is osteolytic (not osteoblastic)
70%
4 most common malignant bone tumors
- Osteosarcoma 40%
- Chondrosarcoma — slooooooow and LARGE, 40-60 yo
- Ewing’s sarcoma — 10-15yo. Need to rule out infection as differential diagnosis
- Giant Cell Tumor — soap bubbly appearance
Codman’s triangle is associated with what malignant bone tumor
Osteosarcoma
What malignant bone tumor occurs in 40-60 you and is sloooooow and LARGE
Chondrosarcoma
What malignant bone tumor occurs in 10-15yo and has a differential diagnosis of infection?
Ewing’s sarcoma
What malignant bone tumor has soap bubbly appearance
Giant Cell Tumor