Chapter 21: Diseases Skin and Eyes

Question 1

What is the characteristics normal microbiota?

Answer 1

Gram-positive salt tolerant microbes
Staphylococci
Micrococcus
Diphtheroids
grow on oils
aerobes on the surface: Corynebacterium xerosis
anaerobes in hair follicles: Propionibacterium acnes
yeast facultative anaerobes: Malassezia furfur
No viruses

Question 2

List disease caused by Papovavirus/Papillomaviruses and treatment.

Answer 2

Warts
treatment
removal
cyrotherapy
electrodessication
salicylic acid
Imiquimod (stimulates interferon production)

Question 3

Diseases caused by pox virus

Answer 3

monkeypox and smallpox

Question 4

mode of transmission for smallpox

Answer 4

respiratory route

Question 5

etiological agent of otis externa “swimmer’s ear”

Answer 5

Pseudomonas aeruginosa

Question 6

etiological agent of erysipelas “holy fire” infection of upper layer of skin

Answer 6

Streptococcus pyogenes

Question 7

list infections caused by Staphylococcus aureus

Answer 7

1. folliculitis: infection of hair follicles
2. sty: folliculitis of eyelas
3. Furuncle: abscess, pus surrounded by inflamed tissue
4. carbuncle: inflammation of tissue under skin
5. impetigo: crusting sores, in newborns
6. TSS
7. scalded skin syndrome

Question 8

characteristics chickenpox

Answer 8

Varicella-zoster virus (human herpesvirus 3)
transmitted thru respiratory route
casues pus filled vesicles
virus may remain latent in dorsal root ganglia
Prevention; live attenuated vaccine

Question 9

mode of transmission of german measles/rubella

Answer 9

respiratory route

Question 10

mode of transmission of cold sores/oral herpes

Answer 10

respiratory route or oral

Question 11

etiological agent of thrush and vaginitis

Answer 11

Candida albicans (yeast)

Question 12

cause and treatment of Candida albicans

Answer 12

Candidasis: may result from suppression of competing bacteria by antibiotics
Thrush: an infection of mucous membranes of mouth
occurs in skin and mucous membranes of mouth
topical treatment with miconazole or nystatin

Question 13

List diseases cause by herpes virus

Human herpesvirus 1 (HSV-1) and 2 (HSV-2)
HSV-1 can remain latent in trigeminal nerve ganglia

Answer 13

Cold sores/fever blisters (vesicles on lips)
Herpes gladiatorum: (vesicales on skin)
Herpetic whitlow (vesicles on fingers)
Herpes encephalitis
chicken pox/shingles
Roseola (6months to 3 yrs old)

Question 14

List characteristics of P. aeruginosa

Answer 14

gram-negative, aerobic rod, opportunistic
Pyocyanin produces a blue-green pus
Psudomonas dermatitis (hot tub rash)
otitis externa (swimmer's ear)
post-burn infection

Question 15

Name the leading cause of blindness in the world

Answer 15

Chlamydia trachomatis
casues trachoma (roughening of inner eyelid)
infection causes permanent scarring, scars abrade cornea leading to blindness

Question 16

Where in your skin is the largest bacterial population?

Answer 16

axillary (armpit) and groin

Question 17

List the characteristics to identify S. pyogenes

Answer 17

gram-postive cocci, coagulase negative
Group A beta-hemolytic streptococci
hemoylsins
Hyaluronidase
Stretolysins
M proteins

Question 18

List the characteristics used to identify S.aureus

Answer 18

gram-positive cocci, coagulase positive
Antibiotic resistant
Leukocidin
Resists opsonization
Survives in phagolysozome
Lysozome resistant 
forms Exfoliative toxin

Question 19

Give the etiological agent and mode of transmission of scabies.

Answer 19

Sarcoptes scabei burrows in the skin to lay eggs

treatment with topical insectisides

Question 20

Rubeola/Measles

Answer 20

i. Measles virus
ii. Transmitted by respiratory route
iii. Macular rash and Koplik’s spots
iv. Prevented by vaccination
v. Encephalitis in 1 in 1,000 cases
vi. Subacute sclerosing panencephalitis in 1 in 1,000,000 cases

Question 21

Rubella/ German Measles

Answer 21

i. Rubella virus
ii. Transmitted by respiratory route
iii. Macular rash and fever
iv. Congenital rubella syndrome causes severe fetal damage
v. Prevented by vaccination

Question 22

Compare measles and rubella

Answer 22

measles virus/ rubella virus
transmitted respiratory route
macular rash and Kopik’s spots/Macular rash and fever
prevented by vaccination
congenital rubella syndrome causes severe fetal damage
Encephalitis in 1 in 1,000 cases and Subacute sclerosing panencephalitis in 1 in 1,000,000 cases

Question 23

Give the etiological agent of Fifth’s disease

Answer 23

a.Etiologic agent is Human parvovirus B19 produces mild flu-like symptoms and facial rash

Question 24

Where did the Fifth’s disease name come from?

Answer 24

Name derived from a 1905 list of skin rashes, which included

1. Measles
2. Scarlet fever
3. Rubella
4. Filatov Dukes disease (mild scarlet fever), and
5. Fifth disease, or erythema infectiosum

Question 25

List the different causes of conjunctivitis (An inflammation of the conjunctiva) pink eye/red eye

Answer 25

commonly caused by Haemophilus influenzae
various other microbes can be the cause
associated with unsanitary contact lenses or makeup