Immunity and infection Flashcards
In the innate immune system what are the physical barriers
mucus skin saliva cilia coughing sneezing stomach acid
What is a white blood cell differential
check for leukocyte count
What does a left shift mean for a WBC differential
large amounts of neutrophils
Eosinophils are related to what two conditions
hay fever asthma
HIV attacks which cells
helper T
When your helper T’s are 250 microliters or less what happens
HIV turns to aids
What are the cardinal signs of inflammation
redness swelling heat pain function impariment
What complement protein are you born with
C3
What are the three ways the complement system gets activated called
Classical (slowest) Lectin Alternative (fastest)
Do all three complement pathways lead to the cleavage of C3 into C3b and a
yes
What does the classical pathway start with
the antibodies IgG or IgM
What does the alternative pathway start with
just C3
What does the lectin pathway start with
lectin binds with a sugar called mannose found on the surface of pathogens
Once the three complement pathways reach C3 what happens
C3 is cleaved into C3b and C3a
What is C3a’s purpose
to attract neutrophils According to the tutor, it also activates basophils and mast cells
What does C3b do
opsonizes the bacteria so phagocytes can recognize it or it acts as an enzyme for C5
What does C3 do to the C5
converts it into C5a & b C5a acts to stimulate the vascular phase of acute inflammation (where there brief vasoconstriction followed by rapid dialation and increased vascular permeability) C5b form together with C6,7,8,9 to form the membrane attack complex that pokes a hole in the microbe
What is the process of stimulating the adaptive immune response
after a phagocyte eats a microbe, it presents a piece of that microbe on its surface then presents that piece to a T cell the T cell then takes that antigen to a B cell who then differentiates into B plasma cells and memory cells the B plasma cells then mass produce antibodies
What is produced during the vascular phase of acute inflammation
histamine and nitric oxide
What are the effects of histamine and nitric oxide
vasodilation
Why is the decrease of blood flow caused by increased vascular permeability and vasodilation benefitial
enables clotting in the blood vessel helps localized infection
What type of protein increases during infection
C reactive proteins
What is a normal CRP level (C reactive proteins)
below 3 mg/L of blood
describe acute
rapid onset last between 2 weeks and 3 months
What cytokines inhibit viral replication
interferons
What is the most common Immunoglobin
IgG
What is the % of each Ig
75% IGG 15% IGA 10% IGM trace amounts for IGE and IGD
Which Ig is passed through the placenta
IgG
Which Ig is largest
IgM
Which Ig is the first to be produced
IgM
Where can IgE’s be found
basophils and mast cells
Cytotoxic T cells (CD8) have what MHC
I
Helper T cells (CD4) have what MHC
II
What are type I hypersensitivity disorders
mediated by IgE includes anaphylactic shock, bronchial asthma, and hay fever
What are type II hypersen disorders
anti-body mediated IgM or IgG includes A ntibody medieated cell destruction T ransfusion reactions H emolytic disease in newborns
What are type III hypersen disorders
involves the creation and deposition of insoluble antigen-antibody complexes that cause systemic and local immune complex disease Some causes are Antibodies, antivenom, foods
What are type IV hypersen disorders
cell mediated CD8’s kill antigen bearing target cells CD4’s release cytokines that damage and kill antigen containing cells examples: Hep A, TB test
If a B or T cell that is autoreactive escapes the first test in the lymphoid tissue how do they get suppressed (Two ways)
for these cells to proliferate after binding to a self-antigen , they need a secondary stimulating signals. With that secondary signal, they can cause more damage Suppression from suppressor T cells
A latex allergy might be a example of what type of hypersen
type IV
What is a immunodeficiency disorder
an abnormality in the immune system that leaves the person more susceptible to infections
What is a primary immunodeficiency
a genetic defect
What is a secondary immunodef
acquired
What type of virus is HIV
retro
What is it and what does a retro virus do
its an RNA virus that injects its DNA into the hosts DNA
What cell does HIV affect
CD4 T cells (cell mediated immunity)
How is HIV transmitted
through blood or body fluid (like semen, breast milk, and vaginal secretions)
What is the most frequent mode of transmission of HIV
sexual contacts
What is HIV’s pathogenesis
binds to CD4 molecule uses the hosts reverse transcriptase to turn RNA into DNA integrates its DNA into the hosts DNA the host cell then transcribes and translates proteins and in the process end up also transcribing and translating new HIV viruses protease cleaves some the polyprotein chains of the new viruses these new viruses then coat themselves with the cell membrane as they leave the host cell
What test is used for diagnosis of HIV
ELISA (enzyme-linked immunosorbent assay)
What are some common opportunistic pathogens that affect people with AIDS
Candida TB
What disease is a commonly associated with AIDS
dementia
What are the three phases of HIV infection
primary infection- symptoms similar to MONO like fever and fatigue, decrease in CD4 count latent period- no signs or symptoms, lasts average of 10 years, gradual drop of cd4 T cell count Stage 3 (overt AIDS)- occurs when CD4 T count drops below 200 cells/microliter, 2-3 years to death usually for people who don’t get treatment
HIV usually turns to AIDS after
7-10 years
What are some common conditions that AIDS patients get
opportunistic infections and cancers wasting syndrome dementia malignancies
What are some common examples of malignancies you can get from HIV
Kaposi sarcoma, non-hodgkins lymphoma, and non-invasive cervical carcinoma
What are pressure ulcers caused by
unrelieved pressure that impair blood flow and lymph
What does pressure ulcers cause
ischemia
What are the ways ischemia happens
unrelieved pressure shearing force moisture friction
Where do ulcer pressure usually occur
sacrum coccyx heels hips elbows knees ankles cranium
Who is at the most risk of ulcer pressures
injured elderly quadriplegia critical care setting
How do you prevent ulcer pressures
move patient every two hours
What are the stages of pressure ulcers and describe them
stage 1- reddened skin stage 2- skin loss of epidermis or dermis stage 3- skin loss involving damage or necrosis of subcutaneous that may extend to but not through the fascia stage 4- necrosis, damage to muscle, bone, supporting tissue
What type of disease is Psoriasis
immune mediated
Is there a cure for psoriasis
no, lifelong
Where is psoriasis usually found
knees elbows scalp
What happens in psoriasis
skin cells are mistaken for pathogens, causing an immune reaction that cause a build up of cells giving a silvery look
What are some bacterial skin infections
Cellulitis Impetigo
What is Cellulitis
infection of the subcutaneous and dermis tissue, usually caused by staph aureus
Where does cellulitis usually occur on the body
legs and face
What is the pathology of cellulitis
inflammation of connective tissue and the dermis and subcutaneous
What are the manifestations of Cellulitis
tingling feeling redness heat pain
What is Impetigo
superficial skin infection caused by staph aureus or beta hemolytic streptococcus
Is Impetigo contagious
highly
What are some manifastations of impetigo
yellow honey crusted sores around the mouth
Is impetigo itchy
it can be
is impetigo painful
no
How is impetigo spread
direct contact with the lesions
How is impetigo treated
Bactroban or systemic antibodies in sever cases
What is herpes simplex virus
infection of skin and mucous membranes
Explain the two different types of HSV
HSV-1 : usually infects the mouth HSV-2 : usually infects genitals
What are the primary symptoms of HSV-1
painful vesicles ulcers of the lips, tongue, and palate fever sore throat
What are the recurrent symptoms of HSV-1
begin with burning or tingling in the area of the primary infection
What are some factors that increase the chance of having an outbreak of HSV-1
stress ultraviolet B exposure
Is there a cure for HSV
no, patients usually take antihistamines, antiinflams, and anesthetics sunscreen also helps block ultraviolet B
What are shingles
vesicular eruption along dermatomal segment of the skin
How are shingles and chicken pox related
they are both caused by the same virus, varicella-zoster chicken pox is more contagious but shingles can be transmitted through nonimmune contact
How does age affect shingles
people older than 60 are the most effected
What else increases the risk of getting shingles
HIV cancer treatments longterm corticosteroid treatments
What are the symptoms of shingles
pain, tingling, and extreme sensitivity along the effected dermatome
Where on the body does it usually effect
back to groin face thoracic region
How long does HSV sores take to heal
2-6 weeks
What is the prodromal phase of shingles preceded by
lesions (rash)
How long might the prodromal phase of shingles last
1-3 days
What do the lesions of shingles look like
erupted vesicles with erythematous bases that follow sensory nerves
What is the lifespan of new crops of vesicles in shingles
erupt for 3-5 days dry up, form crusts, fall off last 2-3 weeks
What are some complications that can arise from shingle vesicles on the face
they can damage the eye leading to blindness
How is shingles treated
administration of antiviral agents preferably with 72 hours of the rash development vaccine
What is scabies
a contagious disease caused by mites that burrow under the skins
How is scabies transmitted
contact with person, bedding, or clothing
What is the pathophysiology of scabies
eggs of the mites are laid in the stratum corneum, eggs hatch and become adults over the next 3 weeks
What are the manifestations of scabies
appears after 3-5 weeks of infection the primary lesion are burrows, papules, and vesicles intense itching, worse at night secondary infections and crusting develop from scatching
where on the body does scabies affect the most
hands and feet, webbed skin the most
What is thrush (oral candidiasis)
fungal infection of candida albicans on the mucous membranes of the mouth
What are the signs of thrush
thick white lesions on the tongue or inner cheek
What are the symptoms
the lesion can be itchy and painful
What are the risk factors of thrush
people coming off systemic antiboitics warm, moist environment pregnancy weakened immunity diabetes
What is pediculosis
lice, parasites live on the surface of the skin and suck blood to survive
How is lice transmitted
direct contact infected fomite
What do lice secrete
toxic saliva
What can the toxic saliva and mechanical trauma of lice cause
pruritis (severe itching)
How often do female lice reproduce
every 2 weeks
Who is most commonly affected by lice
children
how is lice treated
medicated shampoo patient combing of the hair
What is molluscum contagiosum
a highly contagious poxvirus, grows in the folicular epithelium
How is molluscum contag transmitted
direct contact infected fomites
What does molluscum contagiosum look like
the lesions are discrete, pitted, and dome shaped with little black dot in the middle
Where does mollus contag affect on the body
anywhere
What happens to the lesions of mollus contag
they erupt then scab over
Is treatment of molluscum contag needed
usually not
What is basal cell carcinoma
slow growing tumors in the deepest layer of the epidermis
What causes basal cell car
damage from sun rays
What does basal cell car usually look like
well defined lesions with rolled borders and depressed centers
Does basal cell car metastisize out of the skin
no
How does basal cell car grow
laterally
What is chicken pox
contagious disease thats caused by the varicella-zoster virus
What is the timeline of chicken pox
11-20 days of incubation contagious for 1-2 days before rash through 5 days after crusting
What is the pathology of chicken pox
mascular rash papular vesicular crusted lesion
Where does chicken pox affect the body
trunk face then later to the etremeties
Is chicken pox itchy
yes
What are some complications in adults with chick pox
H ematuria E pitaxis L aryngeal edema V aricella pneumonia
What are the 5 things to monitor for skin cancers
A- asymmetry B- border C- color D- diameter E- evolving
What is squamous cell carcinoma
Tumors that grow in the epidermis
What are squam cell cars manifestations
red scaly patches with irregular borders open sores with raised borders and crusted surface
Where is squam cell car commonly found
areas of the head shoulders back hands
What areas are the most vulnerable
rim of ear and lower lip
What is melanoma
cancer of melanocytes
Is melanoma malignant
yes
can melanoma metastisize
yes
What are the risk factors of melanoma
sun exposure family history
What does it look like
asymmetrical uneven borders more than one shade of color > 1/4 inches
What are examples of granulocytes?
Basophils Eosinophils Neutrophils Mast cells
What are examples of agranulocytes
Monocytes Macrophages Lymphocytes
What is the bacterium that causes Lyme disease?
Borrelia Burgdorferi
How is the disease transmitted to humans?
Bite of infected backlegged deer ticks
What are typical symptoms of Lyme disease?
Fever, headache, fatigue, skin rash within 14 weeks
Is Lyme disease curable?
Yes with antibiotics
What is a distinguished feature of Lyme disease?
Target lesion/rash
What is affected in first degree burn and what does it look like?
Epidermis; superficial, read
What is affected in second degree burn and what does it look like?
partial/deep thickness- epidermis and some dermis; blisters, pain, edema, white & waxy
What is affected in third degree burn and what does it look like?
full thickness- epidermis, dermis, subcutaneous tissue: critical, skin graft
What is affected in fourth degree burn and what does it look like?
tissue beneath skin burned; muscle, tendons, ligaments, bones
What is the pathophysiology of electrical injury?
Electrical current enters body –> follows tissue with low resistance –> exists at another site
What are the manifestations of electrical injury?
Difficult to assess fuel extent of burn Tissue around exit wound most severely damaged
What are the consequences of electrical injury?
Systemic: cardiac, acid-base, tissue necrosis Local: devascularazition –> amputation
What is frost bite?
Injury due to exposure to extreme colder
What is the pathophysiology of frost bite?
Ice crystal formation Blood vessels close to the skin constrict –> anoxia, release of inflammatory mediators Generation of oxygen free radicals Prostaglandins and release of proteolytic enzymes
