Microbiology

Question 1

list factors preventing skin infections

Answer 1

dry environment killing microorganisms
sebum contains fatty acids inhibiting bacterial growth
competitive bacterial flora

Question 2

list some skin commensals

Answer 2

staph epidermidis
corynebacterium
propionibacterium

Question 3

list the two most common pathogens causing infections in the skin

Answer 3

staph aureus

group A strep (strep pyogenes)

Question 4

how do you diagnose skin infections

Answer 4

swab of lesion/pus sample

also blood cultures

Question 5

what is the treatment for staph aureus infection

Answer 5

flucloxacillin

Question 6

methicillin resistant staph aureus requires different treatment - what is this

Answer 6

vancomycin or doxycycline

Question 7

what type of skin infections can staph aureus cause

Answer 7

boils
infected cuts 
cellulitis 
impetigo
wound infection

Question 8

what is the most common type of fungal infection of the skin

Answer 8

tinea infection - ringworm

Question 9

where are the following fungal infections located:
1 tinea capitis 
2 tinea corporis 
3 tinea manuum 
4 tinea unguium 
5 tinea cruris 
6 tinea pedis

Answer 9

1 - scalp 
2 - body 
3 - hand 
4 - nail
5 - groin 
6 - feet (athletes foot)

Question 10

what is the appearance of tinea infection

Answer 10

red circular rings which may overlap and cause itching - may scale and cause plaques

Question 11

ringworm only affects keratinised tissues true/false

Answer 11

true

Question 12

what organisms cause fungal infections of the skin

Answer 12

trichophyton rubrum

trichophyton mentagraphytes

Question 13

what investigations are required for ringworm infection

Answer 13

woods light

skin scraping/nail clippings sent away in dermpak for microscopy and culture

Question 14

what is the treatment for ringworm infection

Answer 14

small area of skin affected - topical clotrimazole or topical nail paint called amorolfine
extensive area/scalp affected - terbinafine orally

Question 15

where is a candida skin infection most likely to occur

Answer 15

warm moist areas where the skin folds eg under the breast, groin and nappy areas in babies

Question 16

what is the treatment of candida infection

Answer 16

clotrimazole cream and oral fluconazole

Question 17

what is cellulitis and what organisms are most likely to cause it

Answer 17

acute infection of the skin and soft tissues, caused by beta-haemolytic strep and staph

Question 18

describe the appearance of impetigo

Answer 18

well defined lesions on nose/lips area with honey coloured crusts on erythematous base - can cause blistering

Question 19

who does impetigo usually affect

Answer 19

children aged 2-5 years old

Question 20

candida infection in the mouth will wipe off with a spatula true/false

Answer 20

true - lichen planus will not

Question 21

which virus causes chickenpox

Answer 21

varicella zoster virus

Question 22

what is the presentation of chickenpox

Answer 22

widespread rash forming into vesicles then scabbing, inflamed skin with fever and itch

Question 23

list some complications of chickenpox

Answer 23

secondary bacterial infection
pneumonitis
scarring
encephalitis

Question 24

what are the precursors of severity with chickenpox

Answer 24

extremes of age - neonatal chickenpox if contracted in womb severe
depressed cell mediated immunity

Question 25

what is shingles

Answer 25

reactivation of varicella zoster virus

Question 26

describe the distribution of shingles

Answer 26

dermatomal

Question 27

what is the presentation of shingles

Answer 27

tingling pain and erythematous vesicles which turn to crusts pain is neuralgic in affected area

Question 28

what is post herpetic neuralgia

Answer 28

neuralgia from shingles lasting more than 4 weeks

Question 29

what are some complications of shingles

Answer 29

ramsay-hunt syndrome - vesicles and pain in auditory canal facial palsy if CN VII affected tinnitus, deafness and vertigo if CN VIII affected

Question 30

who is the shingles vaccine routinely available for

Answer 30

over 70s

Question 31

what is the initial presentation of herpes simples virus

Answer 31

primary gingivostomatitis - extensive red ulceration around the mouth lasting up to a week

Question 32

what is the secondary presentation of herpes simples virus

Answer 32

cold sore - blistering rash around vermillion border

Question 33

what type of lesions do HSV type 1 and 2 cause

Answer 33

type 1 - majority of oral lesions, half of genital lesions | type 2 - half of genital lesions and encephalitis in neonates

Question 34

is aciclovir effective in treating HSV in active and latent disease

Answer 34

active yes but not latent disease

Question 35

molluscum contagiosum is self-limiting but what can help remove lesions

Answer 35

local application of liquid nitrogen

Question 36

which virus is the main cause of warts

Answer 36

human papilloma virus

Question 37

list which types of HPV cause which conditions

Answer 37

type 1 - warts and veruccas type 6 and 11 - genital warts type 16 and 18 - cervical cancer

Question 38

HPV vaccine is protective against which types of HPV

Answer 38

types 6, 11, 16 and 18

Question 39

what is the treatment of a wart/verucca

Answer 39

topical application of salicylic acid

Question 40

what causes hand, foot and mouth disease

Answer 40

enterovirus typically coxsackie virus

Question 41

what causes slapped cheek disease

Answer 41

parvovirus B19

Question 42

what is the presentation of slapped cheek disease

Answer 42

initially rash on the face with slapped cheek appearance | as the face changes get lacy macular rash on body

Question 43

what non-dermatological manifestation of slapped cheek disease can affect adults

Answer 43

polyarthritis of the small joints

Question 44

what investigations are carried out for slapped cheek disease

Answer 44

parvovirus B19 IgM antibody

Question 45

list some complications of parvovirus

Answer 45

spontaneous abortion - foetal hydrops is precursor aplastic crises chronic anaemia

Question 46

which animal does orf usually affect

Answer 46

sheep - known as scabby mouth disease

Question 47

what is the presentation of orf

Answer 47

large, firm, fleshy nodule on typically farmers hand - usually self-limiting

Question 48

what organism causes syphilis

Answer 48

bacterium cause treponema pallidum

Question 49

how does primary syphilis present

Answer 49

chancre - painless ulcers at the site of entry usually mouth or genitalia

Question 50

how does secondary syphilis present

Answer 50

red rash affecting whole of body esp palms and soles

Question 51

how does tertiary syphilis present

Answer 51

CNS, CVS and gummatous involvement

Question 52

what is the treatment for syphilis

Answer 52

injections of penicillin

Question 53

what causes lyme disease

Answer 53

bacteria borrelia burgdorferi but ticks are a vector

Question 54

what is the treatment for lyme disease

Answer 54

amoxicillin or doxycycline