Microbio Chapter 21 Microbial Diseases Of The Skin And Eyes

Front 1

Stratum corneum

Back 1

- Outermost layer of the epidermis - thin outer portion of the skin - consists of many rows of dead cells

Front 2

Dermis

Back 2

- Inner, relatively thick portion of skin composed mainly of connective tissue

- Hair follicles, sweat gland ducts, and oil gland ducts provide passageways through which microbes can enter and penetrate deeper tissues

Front 3

Perspiration

Back 3

- Provides moisture and some nutrients for microbial growth

- Contains salt, lysozyme and antimicrobial peptides also

Front 4

Sebum

Back 4

- Secreted by oil glands, is a mixture of lipids (unsaturated fatty acids), proteins, and salts that prevents skin and hair from drying out

- Can also be nutritive and inhibitive to pathogens

Front 5

Diphtheroids

Back 5

- Gram positive pleomorphic rods of normal flora

- Typically anaerobic and inhabit hair follicles

- Growth by sebum, produce propionic acid which helps maintain low pH of skin (3-5)

Ex: Propionibacterium acnes

Front 6

Vesicles

Bullae

Macules

Papules

Pustules

Back 6

- Small, fluid-filled lesions

- When they are larger than about 1 cm in diameter

- Flat, reddened lesions

- Raised lesions

- Lesions that contain pus

Front 7

Exanthem

Enanthem

Back 7

- A skin rash that arises from disease conditions

- A mucous membrane rash that arises from disease conditions

Front 8

Staphylococcus

Streptococcus

Back 8

- Two genera of bacteria that are frequent causes of skin-related diseases

- May produce invasive enzymes and damaging toxins

Front 9

Staphylococcus

Back 9

- Spherical gram positive genus of bacteria

- Form irregular clusters

- Many produce coagulase (enzyme that clots fibrin in the blood)

Front 10

1. Nasal
2. 20
3. Golden-yellow
4. positive
5. toxins
6. sepsis
7. opsonization
8. chemotaxis
9. phagosomes
10. MRSA (methicillin-resistant S. aureus)

Back 10

Staphylococcus aureus is carried in the __1__ passages of __2__% of the population. They form __3__ colonies and are coagulase __4__. May produce damaging __5__ and proteins that kill phagocytic cells and cause __6__. Avoids host defenses in the skin. Depending on the strain, can resist __7__, block __8__ of neutrophils, and survive within __9__. __10__ strains are antibiotic resistant.

Front 11

Folliculitis

Back 11

- Infections that enter the body through the hair follicle

Ex: Pimples, sty, furuncles (boil)

Front 12

Abscess

Back 12

- Localized region of pus surrounded by inflamed tissue

Ex: Furuncle (boil)

Front 13

Carbuncle

Back 13

- Extensive damage from when neighboring tissue of the furuncle is progressively invaded

- At this stage, patient has symptoms of generalized illness with fever

Front 14

Impetigo

Back 14

- Highly contagious skin infection (Age 2-5 Susceptible) spread by direct contact

- Mainly caused by staphylococcus aureus but also Streptococcus pyogenes

- Main form is nonbullous sore

- Crusting sores

Front 15

Autoinoculation

Back 15

- Process where pathogen can spread to surrounding areas after penetrating some minor break in the skin

Front 16

Bullous impetigo

Scalded skin syndrome

Back 16

Two serotypes of a staphylococcal toxin in which toxin A remains localized and causes __________ and toxin B which circulates to distant sites and causes ____________.

Toxin B causes exfoliation.

Front 17

Pemphigus neonatorum

Back 17

- Impetigo of the newborn, in which its outbreaks of bullous impetigo are frequent problems at hospital nurseries

Front 18

Toxic Shock Syndrome

Back 18

- Fever, vomiting, and a sunburnlike rash are followed by shock and sometimes organ failure, esp. kidneys

- Result of staphylococcal growth

- Caused by toxic shock syndrome 1 in the bloodstream (TSST-1)

Front 19

Hemolysins

Back 19

- Characteristic of and classifications of streptococci that describe lysing of blood cells

Front 20

Beta-Hemolytic Streptococci

Back 20

- Often associated with human disease, further differentiated into serological groups according to antigenic carbohydrates in their cell walls

Ex: group A streptococci (GAS) = Streptococcus pyogenes that release streptolysins

Front 21

Streptolysins

Back 21

- Enzymes produced by streptococci that lyse red blood cells and toxic to neutrophils

Front 22

M Protein

Back 22

- Antigenic property that subdivide group A streptococci

- Prevents activation of complement and allows microbe to evade phagocytosis and killing by neutrophils, immune system avoidance

- Helps adherence and mucous membrane colonization

- Hyaluronic acid capsule that is poorly immunogenic

Front 23

Group A Strep (GAS)

Back 23

- Produces substances that promote the rapid spread of infection through tissue and by liquefying pus

- Produces virulence factor, 80 immunological types

Ex: streptokinases, hyaluronidase, deoxyribonucleases, streptolysins, M proteins

Front 24

Necrotizing fasciitis

Back 24

- Exotoxin A acts as superantigen

- Group A streptococcal infection precipitated by minor breaks in the skin, destroys tissue as rapidly as surgeons can remove it

- Systemic toxicity

- Often associated with streptococcal toxic shock syndrome which resembles staphylococcal TSS

Front 25

- Bacteremia more likely

- Rash is less likely

- M protein - fibrinogen complex binds to neutrophils

- Higher mortality rate

Back 25

4 Differences between Streptococcal TSS and Staphylococcal TSS

Front 26

Epidermidis

Back 26

- Thin outer portion of skin; composed of layers of epithelial cells

Front 27

Keratin

Back 27

Waterproofing protein coating outer layer of epidermis

Front 28

Lysozyme

Back 28

Enzyme that breaks down bacterial cell walls

Front 29

Mucous Membranes

Back 29

- Line the body cavities open to the exterior

- Tightly packed epithelial cells attached to an extracellular matrix

- Secretes _____; some cells have cilia

- Often acidic

- Often folded to maximize surface area

Front 30

Tears

Back 30

- Contains lysozyme

- Washes the membrane of the eyes

Front 31

1. drying

2. high salt

3. positive

4. cocci

5. staphylococci

6. micrococci

7. sweat

Back 31

The normal microbiota of the skin is resistant to ___1___ and ___2___ concentration. There are large numbers of gram __3__ __4__, such as ___5___ and ___6___. Areas with moisture have higher populations which metabolize ___7___ and contribute to body odor.

Front 32

Postherpetic neuralgia

Back 32

affects nerve fibers and skin, causing burning pain that lasts long after the rash and blisters of shingles disappear.

Front 33

1. Rubeola

2. Measles Virus

3. Ribonucleic acid

4. Morbillivirus

Back 33

Measles, AKA ____1____ is caused by the ___2___ which is an enveloped ___3___ acid of the genus ___4___.

Front 34

Measles

Back 34

- Coldlike symptoms; macular rash; Koplik's spots: Red spots on oral mucosa opposite molars; Encephalitis in 1/1000 cases

- Respiratory

- Prevention: MMR vaccine; <1 year old cannot receive; 95% effective but cases occur where people do not develop or retain good immunity

Front 35

Measles

Back 35

virus replicates in nose and throat cells; 5-7 days after exposure, infection spread through blood to skin, eyes and respiratory tract; rash appears after 3-4 days spreading from face and neck to trunk and extremities; most persons recover but severe forms involve bleeding from skin and mucosa; <5 years develop otitis media and pneumonia; Subacute sclerosing panencephalitis

Front 36

Subacute sclerosing panencephalitis

Back 36

- mild mental deterioration (memory loss), changes in behavior (irritability) followed by disturbances in motor functions

- Seizures and blindness may occur. May lose the ability to walk as muscles stiffen or spasm; progressive deterioration to comatose state, then to persistent vegetative state. Death is usually result of fever, heart failure, or brain's inability to continue controlling autonomic nervous system

- Rare, occurs 1-10 years after recovery of measles

Front 37

Streptolysins

M Proteins

Strepokinases

Hyaluronidase

Back 37

4 substances secreted by Streptococcus pyogenes (GAS)

Front 38

Streptolysins

Back 38

- Enzymes that lyse red blood cells

Front 39

Hyaluronidase

Back 39

- Enzyme that dissolves connective tissue

Front 40

Streptokinase

Back 40

- Enzyme that dissolves blood clots

Front 41

1. Variola

2. Orthropoxvirus

3. Respiratory Routes

4. Systemic

5. Major

Back 41

Smallpox AKA ___1___ is caused by the ___2___, which are typically transmitted via ___3___ and become ___4___. Many cause problems in children and developing fetuses. ___5___ type has 20% mortality and __6__ type has less than 1%.

Front 42

Smallpox

Back 42

- Considered potential bioterrorism agent

- Vaccination can completely eradicate from human population

Front 43

1. Varicella

2. Varicella-Zoster

3. Herpes-Zoster

4. Reye's

5. Aspirin

6. Ganglia

7. Attenuated

Back 43

Chickenpox AKA ___1___ is caused by the ___2___ virus whereas Shingles is caused by the ___3___ virus. ___4___ Syndrome is from a severe complication of chickenpox, leading to vomiting and brain dysfunction. __5__ can increase risk. Virus becomes latent in the central nerve __6__, prevention can come from live __7__ vaccine.

Front 44

Chicken Pox

Back 44

- Breakthrough can occur if previously vaccinated

- Symptoms include pus-filled vesicles

- Respiratory mode of transmission

Front 45

Shingles

Back 45

- Reactivation of the latent varicella-zoster virus that moves along peripheral nerves to the skin; due to stress or lowered immunity; follows distribution of affected cutaneous sensory nerves along one side of body

- Can lead to postherpetic neuralgia

Prevention: Zoster vaccine; Treatment: antiviral drugs may lessen symptoms

Front 46

1. cold sores

2. genital warts

Back 46

Herpes Simplex has subtypes HSV-1 that causes __1__ and HSV-2 that causes ___2___. 90% of the population is infected, are not the cause of canker sores.

Front 47

1. Rubella

2. MMR

3. Congenital rubella

4. 15%

Back 47

German Measles caused by __1__ can be prevented with the __2__ vaccine but is not recommended for pregnant women. ___3___ syndrome can cause fetal damage, deafness, heart defects, mental retardation and has a __4__ mortality rate.

Front 48

German Measles

Back 48

- 2 to 3 week incubation period

- Macular rash and light fever

Front 49

Fifth disease

Back 49

- AKA erythema infectiosum

- Caused by human parvovirus B19

- Mild flu-like, "slapped-cheek" facial rash

Front 50

Roseola

Back 50

- Caused by Human herpesvirus 6 and 7

- High fever and body rash

- Recovery within 1-2 days, leads to immunity

Front 51

Hand-foot-mouth disease

Back 51

- Caused by the enterovirus

- Fever and sore throat, rash on specific areas

- Usually in children, spread by mucous or saliva

Front 52

Dermatomycoses

Back 52

- Cutaneous infection caused by ringworm AKA tinease (fungal)

- Metabolizes keratin

Front 53

Tinea capitis: Scalp

Tinea cruris: Jock itch

Tinea pedia: Athlete's foot

Tinea unguium: Nails

Back 53

4 Types of Ringworm and where it infects

Front 54

Candidiasis

Candida albicans

Back 54

- Caused by yeast (fungal) that forms pseudohyphae, making it resistant to phagocytosis, results when antibiotics suppress competing bacteria or a change occurs in the mucosal pH

- Fulminating disease in the immunosuppressed

Front 55

Scabies

Back 55

- Sarcoptes scabiei mites lays eggs after burrowing in skin

- Causes inflammatory skin lesions

- Treatment: permethrin

Front 56

Conjunctivitis

Back 56

- AKA pink eye

- Eye membrane inflammation associated with unsanitary contact lenses

Front 57

Conjunctivitis

Back 57

- Can be caused by Haemophilus influenza, pseudomonads (Gram negative aerobic) or adenoviruses

Front 58

Trachoma

Back 58

- Leading cause of blindness worldwide; secondary infection can also be factor

- Caused by chlamydia trachomatis, through hand contact or flies

- Permanent scarring abrading cornea

- Treatment: Oral azithromyocine