Modules 12-14 Flashcards
(105 cards)
1
Q
CNS vs PNS structures
A
CNS: brain and spinal cord
PNS: nerves out toward body
2
Q
3 functions of NS
A
sensory, integrative, and motor
3
Q
3 meninges (outer>inner)
A
- Dura mater dural space -Arachnoid mater subarachnoid space -Pia mater
4
Q
Which space in the meninges is filled with CSF?
A
subarachnoid space
5
Q
fn of CSF
A
- provide nutrition
- liquid cushion
6
Q
Defenses of the nervous system (3)
A
- bony casings (protect brain and spinal cord)
- cushion CSF/meninges
- BBB (selective permeability of vessels)
7
Q
BBB drawback
A
difficult to administer drugs (ie ABX) if there is an infection.
8
Q
Immunologically privileged def
A
structure can mount only a partial immune response (have a decreased innate immunity, can tolerate partial invasion and not elicit inflammation/response.
9
Q
Which cells in the CNS have phagocytic capabilities?
A
microglia
10
Q
general communication flow between neurons
A
neurotransmitter across synapse>dendrites>integration at soma>axon (schwann cells and myelin help speed up) >axon terminals
11
Q
Normal biota of the nervous sytem
A
currently thought to be sterile- lack normal biota
12
Q
Symptoms of meningitis
A
- photophobia
- headhache
- painful/stiff neck
- fever
- incr WBC in CSF
13
Q
Meningitis caused by Neisseria meningitidis aka
A
meningococcus
14
Q
which organism cause most serious form of acute meningitis
A
bacteria
15
Q
Describe meningitis caused by Neisseria meningitidis
A
-gram neg diplococci (round cells in pairs)
-accounts for 25% of cases
-most serious form of acute meningitis (rapidly fatal, epidemics)
-enters via respiratory
-capsule, endotoxin
-cytokine activity>vessel damage>Petechiae
-vaccines(3)
TX: Penicillin G
16
Q
what are Petechiae?
A
red/purple lesions, from damage to blood vessels and hemorrhage as a result of cytokine activity in meningitis
17
Q
Describe meming by Streptococcus pneumoniae
A
-gram pos, flat coccus
- aka pneumococcus
-most freq community-acqu infection
-most strains ABx resistant
-polysac capsule-avoid phagoc
-produce alpha-hemolysin and hydrogen peroxide=> CNS damage
-2 vaccines
TX: vancomyciin-ceftriaxone
18
Q
Mening by H influenzae
A
- gram neg, coccobacillus
- aka Hib (vaccine available)
- less common since vaccine- most cases now caused by nonserotype B strains
19
Q
Mening by Listeria monocytogenes
A
-gram pos, coccobacilli/long filament
-non-fastidious (salty, pH extreme, cold)
-assoc w unpausterized foods
-causes Listerosis> septicemia in elderly, immunocomp, and fetus
-can cross placenta=spont abortion
Prev: pausterization
TX: abx
Diag: ELISA
20
Q
which kind of meningitis is sometimes classified as meningoencephalitis?
A
meningitis caused by Cryptococcus neoformans
21
Q
Describe meningitis by Cryptococcus neoformans
A
- aka cryptococcosis
- fungus (sphere.ovoid), buds and large capsule
- gradual onset, highest rates in AIDS pts
- TX: antifungals
22
Q
Describe meningitis by Coccidoiodes species
A
-aka Valley Fever (assoc with farming/mining)
-fungus @25 C= moist white/brown colony (arthrospores)
-fungus at 37-40 C= parasitic phase- Spherule
-arthrospores in env>inhaled>temp=spherules
TX: antifungals
23
Q
Describe viral meningitis
A
-mostly caused by enteroviruses
-mainly in children
-milder than bacterial/fungal (resolves in ~2 wks)
-Common cause: Herpes simplex virus HSV-2 (concur genital infection)
TX: supportive, or specific antivirals
24
Q
describe neonatal/infantile meningitis
A
common causes:
-E. coli K1 strain (birth canal), most in preemies=> brain damage
-Strep agalactiae (group B strep)
in utero,most freq in female urogen tract
-Cronobacter sakazakii-in dry environments. baby formula
25
Meningoencephalitis
caused by two amoebas
- Naegleria fowlery
- Acanthamoeba
26
Acute encephalitis causes in midwest
-West Nile virus (birds/mosquito)
- La Crosse Virus (squirrels/mosquito)
-Jamestown Canyon Virus (deer/mosquito)
-Powassan Virus (beaver/mosquito)
-Easter equine encephalitis virus (birds//horses/mosquito)
Herpes Simplex Virus
27
Describe Botulism
-intoxication by an exotoxin (produced by clostridium botulinum)
-3 forms: food-borne, infant, wound botulism
Toxin in bloodstream>neuromuscular junctions> prevents acetylcholine release= flaccid paralysis
-exotoxin can be used cosmetically (migraines, muscle spasms)
28
Viral meningitis vs viral encephalitis
- encephalitis brain only
- encephalitis can often go undiagnosed
- viral meningitis less life threatening
29
Polio vaccine list
IPV (inactivated) - Salk 1954
| OPV (oral)- Sabin 1960
30
Polio targeted for eradication because
- affects children
- Polio prev known as Infantile paralysis
- worldwide devastating effects of especially paralytic polio
31
How does rabies infect humans?
-bite of a wild/stray animal (which is infected)
-also donated organs/tissues
-virus in wound>travels to brain, multiplies>to sites heart, eyes>disorientation/seizures/coma.cardiac arrest>death
glycoprotein envelope make it esp viral
32
what is one effective preventative measure against rabies?
Vaccinating domestic animals, animal handlers and travelers
33
Describe African Sleeping Sickness
- cause by Trypanosoma brucei (hemoflagellate, trans Tsetse fly)
- beh changes, fever, fatigue, slurred speech, local paralysis
- Death from coma, secondary infections, heart damage
34
Describe Toxoplasmosis
| subacute encephalitis
- usually asymptpmatic
- 33% mother->fetus transm
- congenital - severe defects (stillbirth, hydrocephalus, liver failure)
- In FELINES
35
Primary amoebic meningoencephalitis PAM
- caused by Naegleria fowleri (amoeba) enters subarach space
- resistant to temp extremes, mild chlorination
- associated with swimming pools
- rapid mass destruction
36
Main layers of the skin (outer>inner)
1. epidermis
- stratum corneum
- stratum basale
2. dermis
3. subcutaneous layer
37
Anatomical features within the skin
- sebaceous gland
- sweat gland duct
- sensory nerve fibers
- apocrine sweat glands
- arrector pilli muscle
- arteries and veins
- hair follicles, and shafts
38
List the defenses of the skin
- antrimicrobial peptides: disrupt bacterial membranes
- sebum: low pH, antimicrobial, prov nutrients
- sweat: low pH, inhibit microbe
- lysozyme
39
Fn stratum corneum
-keratin- protect against abrasion/damage and water repellent property
40
Fn stratum basale (basal layer)
the origin of cells that go to epidermis (rapidly produce so they can be shed)
41
Fn dermis
-hold all connective tissue, blood and lymph vessels, sweat glands
nutrient
Damage to it- severe bleeding
42
Fn subcutaneous layer
mainly composed of adipose connective tissue
43
Normal biota of skin
- usually inhospitable (dry, salty)
- microbes that can survive in this- most common in moist areas, skin folds, follicles and ducts
- help keep other microbes from taking over
- Staph epidermidis, Propionibacterium, Staph aureus
44
What percent of the population carries Staph aureus as normal biota?
4%
45
list the vesicular/pustular rash diseases
- chickenpox, shingles
- smallpox
- hand, foot, and mouth disease
46
MRSA- causative agents
```
Staphylococcus aureus (community-acqu)
-raised, red, skin lesions, pus, common with shaving injury
-multiple ABX resistant
(hospital acqu: systemic infection)
Hygiene, ABX
```
47
Impetigo- info, agents
Staph. aureus, Strep pyogenes
-red sores, peeling/flaky skin
-most common in children
Hygiene, ABX
48
Cellulitis- info, agents
Staph aureus, Strep pyogenes, MRSA, bacteria/fungi
-painful, tender, swollen, red lines, often in lower leg
-often complication post surgery
ABX
49
what is SSSS?
Staphylococcal scalded skin syndrome
50
SSSS info, agents
```
Staph aureus
-systemic form of impetigo
-often in newborns and babies
-toxins A and B= bullous lesions
-wrinkled tissue paper skin, peeling
ABX
```
51
Gas gangrene info, agents
aka: Clostridial myonecrosis
Clostridium perfringens and other bacteria
- edospores need anaerobic conditions-> endotoxin
2 forms: 1)anaerobic cellulitis (localized)
2) true myonecrosis (spread to healthy tissue)
SX removal, ABX
52
Chickenpox info, agent
Varicella-Zoster Virus (Human herpes Virus 3)
-mild, 2-3wks, superficial lesions
*live attenuated vaccine*
latent virus- reactivation=> SHINGLES (asymetrical lesions in trunk/head, attenuated vaccine also)
53
Smallpox info, agent
```
Variola virus
variola major: more severe, toxemia, highly virulent
variola minor: less dense rash
-Bioterror Catego A (natural elim 1977)
-deep lesions, scar tissue
*live virus vaccine*
```
54
Hand, foot, mouth disease
Enteroviruses (Coxsackie)
-common in children, babies
-red, painful spots in mouth, palms, soles, buttocks, genitals, knee/elbow
hand hygiene
55
List the maculopapular rash diseases
- Measles (Rubeola)
- Rubella
- Fifth disease
- Roseola
56
Measles info, agent
aka Rubeola
- Measles virus
- red spots- head-> body
* live attenuated Measles vaccine since 1963 (part of MMR)*
- sequelae: laryngitis, broncopneumonia, secondary infections
57
Rubella info, agent
```
Rubella virus
-mild red rash, 3 days
-Congenital Rubella-serious=> 1st trimester infectin,miscarriage, birth defects
*Live attenuated vaccine (MMR)*
vaccinate before conception
```
58
Describe congenital rubella
- infection in womb 1st trimester can
- induce miscarriage, birth defects
- vaccinate before conception
59
Fifth disease info, agent
```
Parvovirus B19 (human)
-face rash, 'slapped face'- spreads to limbs/trunk persists for weeks
```
60
Roseola info, agent
Human Herpes Virus 6
- fever ~3 days, can lead to seizures, some get rash
- common in babies
- 100% US pop infected by adulthood
61
Warts info, agents
```
Human papilloma viruses
-in everyone almost
-seed warts: raised, rough growth- almost anywhere, fingers common
-plantar warts deep, painful
-flat wart: smooth, trunk/face/elbow
TX: cryosurgery
```
62
Molluscum contagiosum
Molluscum contagiosum m viruses
- smooth, waxy nodules, milky fluid
- on face, limbs, trunk, genitals
63
List the large pustular skin legions
- Leishmaniasis
| - Cutaneous Anthrax
64
Leishmaniasis info, agent
Leishmania parasites (trans by female sand flies)
-large lesions
2 forms: Cutaneous: localized infection-> capillaries
Mucocutaneous: skin and mucous membranes
65
Cutaneous Anthrax info, agent
Bacillus anthracis
- eschars (dark, scabs) as endospores enter and germinate in skin
- 20% mortality if untreated
66
List the mycoses
- Ringworm (cutaneous mycoses)
| - Tinea Vesicolor (superficial mycoses)
67
Ringworm (cutaneous mycoses)
```
Dermatophytes: 39 species of
-trychophyton
-Microsporum
-Epidermophyton
"tinea ___" capitis, barbae, corporis, cruris, pedis, ungulum
includes psoriasis
```
68
tinea capitis in the
scalp
69
tinea barbae in the
beard
70
tinea corporis in the
smooth, bare skin all over
71
tinea cruris in the
"jock itch" groin, perineal, scrotum
72
tinea pedis in the
foot (athlete's foot)
73
tinea ungulum in the
nails
74
Which of the skin conditions have vaccines available?
- Chickenpox (live attenuated)
- Shingles (live attenuated)
- Smallpox (live virus)
- Measles (live attenuated MMR)
- Rubella (live attenuated MMR)
-cutaneous anthrax (not widely used)
75
Mycoses definition
infection by fungus: athlete's foot (tinea pedis)
all the tineas
76
MRSA currently- updates
-decline in hospital associated, but decline recently slowed
-increasing incidence in community
hygiene
tailored interventions: decolonization (reducing asymptomatic carriage)
77
fn of the conjuctiva
-thin membrane-like tissue that covers the eye and eyelid
| secretes oil/mucus for lubrication
78
fn cornea
5-6 layers of epithelial cells, protect 'windshield'
79
fn tears
oil, mucous, fluid- flushing lubrication
80
Are the eyes immunologically privileged?
Yes, reduced innate immunity to protect the vision
| -anterior chamber is mostly cut off from blood supply, less active lymphocytes
81
list the normal defenses of the eye
- tears
- sclera
- conjunctiva
- cornea
- immune privilege (dec blood supply and lymphocyte activity)
82
Normal biota of the eye
- sparse, diverse
- Corynebacterium dominate
- diphtheroids, staphylococci, micrococcus, streptococci, yeasts, neisserias
83
Conjunctivitis info, agent
- Bacterial: Chlamydia trachomatis, Neisseria gonorrhoeae, Staph aureus, Strep pneumoniae, H. influenzae, Moraxella
- Viral: adenoviruses
- neonatal: chlamydia t., N. gonorrhoeae
- milky discharge in bacterials, clear exudate in viral
- redness, swelling, photophobia
84
Ocular Trachoma info, agent
Chlamydia trahcomatis
- chronic epithelial cell infections, inflamm, scarring
- most common cause of blindness worldwide
- most prevalent in children 3-5y.o.
85
Keratitis info, agent
Herpes simplex, Acanthamoeba keratitis (tap/fresh water), other organisms if trauma to eye
- can lead to complete corneal destruction
- amoeba- water- common in contacts users
86
River blindness info, agent
Onchocerca volvulus (transm by black flies_, Wolbachia bacteria
- chronic paratisic infection, worms often visible in eye
- endemic to Africa, central and south america
87
Differential diagnosis difference between neonatal conjunctivitis, non-neonatal conjunctivitis
Neonatal conjucntivitis is transmitted vertically, during birth, serious eye damage, also herpes simplex can cause neonatal
-neonatal treatment is started even if only suspected of infection
88
which test can help us differentiate between staph aureus and strep pyogenes?
Catalase test
Staphs: catalase +
Streps: catalase -
89
Upper digestive tract organs
- mouth
- salivary glands
- tonsils
- glands, adenoids,
- esophagus
- stomach
90
lower digestive tract organs
- small intestine
- pancreas
- liver
- gallbladder
- large intestine
- rectum/anus
91
Normal biota of the GI tract
many species
~600 species in mouth (strep, lactobacillis..)
~200 esophagus and stomach (strep, staph,clostrid, bacilli)
~10X11 in large intestine (strep, peptostrep, entero, eschiria, lactobacilli)
92
Accessory organs of the GI tract
- salivary glands
- liver
- gallbladder
- pancreas
93
Normal defenses of GI tract
```
Upper: lysozyme, tonsils/adenoids
Lower:
-immune cells (GALT gut assoc-lymphoid tissue, peyer patches in SI)
-secretory IgA, rich biota
-bile
```
94
Dental caries info, agent
Strep mutans, Strep sobrinus
- most common infectious disease in humans
- metabolic activity of bacteria=dissolution tooth suface (enamel disruption)
- rates variable upon: region, carb consumption, genetics...
95
Periodontitis info, agents
Microbial community composition (biofilms)
Stage 1: Gingivitis: inflammation, inc bleeding, pockets, bone disruption
Stage2: Necrotizing Ulcerative Gingivitis: 'trench mouth', ulcers, severe pain, bleeding, necrosis.
96
Mumps info, agents
Mump virus genus Paramyxovirus
- salivary gland inflammation (big, on cheek and neck)
- can invade testes, ovaries, heart, meninges (in some cases can cause sterility)
* MMR vaccine*
97
Gastritis info, agent
Helicobacter pylori (entrenches, produces urease=breakdown epithelial tissue)
- sharp burning abdominal pain
- gastric/peptic ulcers: lesions in mucosa (stomach/SI)
- affects half the world
98
Acute diarrhea info, agents
several causes: Salmonella, E. coli most common
- contaminated food transmission
- 3+ loose stools in 24hr
- H,O,K antigens to ID gram neg components
99
what do the H,K,O antigens help detect?
H: flagella
K: capsule
O: cell wall
100
Acute diarrhea defined as
3+ loose stools in a 24 hr period
101
Salmonella diarrhea info
salmonella large genus of bacteria
- they ferment Glu, produce hydrogen sulfide
- resistant to bile and other chemicals
- cause enteric fever, septicemia, Typhoid fever
102
Shigella diarrhea info
gram neg rod (non-spore)
Shigella sonnei, S. flexemi
-shigella dysenteria:most severe (blood in stool)
-Shiga toxin (endotoxin) > disrupts protein synthesis> fever, villi damage, bleeding
103
E. coli diarrhea info
- contaminated food,water
- some produce shiga toxin (STEC): hemolytic uremic syndrome
- non toxin: five categories
104
Campylobacter diarrhea info
- gram neg
- one of most common bacterial causes
- fever, vomitting, diarrhea, ~2 weeks
- burrow in the mucus
105
C. diff diarrhea
- gram pos, endospore forming
- pseudomembranous colitis
- broad spectrum ABX
- enterotoxins A & B=necrosis on intestinal wall
