Bacterial infections

Question 1

characteristics of impetigo

Answer 1

• pustules
• honey-coloured crusted erosions
• plaques

Question 2

RFs that may cause impetigo

Answer 2

• chickenpox; insect bite

Question 3

main causative agent of non-bullous impetigo

Answer 3

staph (most common)/strep

Question 4

evolution of appearance of non-bullous impetigo (trauma)

Answer 4

pink macule –> vesicle/pustule –> crusted erosions

Question 5

main causative agent of ecthyma impetigo

Answer 5

strep pyogenes

Question 6

evolution of appearance of ecthyma impetigo

Answer 6

non-bullous –> punched-out necrotic ulcer

Question 7

which type of impetigo often leaves scars

Answer 7

ecthyma

Question 8

how do staph exfoliative proteins infect skin in bullous impetigo

Answer 8

cleave off epidermis

Question 9

evolution of bullous impetigo

Answer 9

small vesicles –> flaccid transparent bullae

Question 10

difference between cellulitis and erysipelas & how is it distinguished

Answer 10

• erysipelas is an acute, superficial form

- well-defined, red, raised border

Question 11

is cell & ery unilateral or bilateral mostly

Answer 11

unilateral

Question 12

causes of cell & ery

Answer 12

• s aureus

- strep pyogenes

Question 13

clinical features of folliculitis

Answer 13

deep/superficial tender red spots with surface pustule

Question 14

types of folliculitis

Answer 14

• acne variants

- buttock folliculitis

Question 15

causes of folliculitis

Answer 15

• s aureus (most common)
• pseudomonal aeruginosa (poorly chlorinated water)
• viral: herpes simplex, zoster
• yeast/fungi: candida, tinea capitis
• infestations: hair follicle mites, scabies

Question 16

intertrigo is

Answer 16

rash in flexors

Question 17

general clinical features of intertrigo

Answer 17

• inflammation & uncomfortable

- moist –> fissures & peeling

Question 18

RFs intertrigo

Answer 18

• obesity
• genetic tendency
• hyperhidrosis

Question 19

how to distinguish infectious vs inflammatory intertrigo

Answer 19

• infectious –> unilateral & asymmetrical

- inflammatory –> bilateral

Question 20

evolution of chicken pox

Answer 20

red papules –> vesicles

Question 21

adult infection of chickenpox can show the following prodromal symptoms

Answer 21

• 48hrs before rash
• fever
• malaise
• headache
• loss of appetite
• abdo pain

Question 22

definition of herpes zoster (shingles)

Answer 22

localised painful rash caused by reactivation of VZV

Question 23

describe symptoms and evolution of HZV

Answer 23

• area affected: s nerve pain, fever, headache, lymphadenopathy
• 1-3 days: blistering rash
• red papules –> crust pustules

Question 24

post-herpetic neuralgia

Answer 24

Persistence/re-occurance of pain in the same area more than 1 month after onset of herpes zoster. Most common in facial infections and older age

Question 25

type of herpes simplex virus that is more symptomatic

Answer 25

type 2

Question 26

gingivostomatitis symptoms of type 1 HSV (oral & facial infections) in children 1-5

Answer 26

- fever - restlessness - excessive dribbling & bad breath - problems with gums - white vesicles --> yellow ulcers - lymphadenopathy

Question 27

type 2 HSV is more common in

Answer 27

sexual activity

Question 28

what is eczema herpeticum that can result from HSV

Answer 28

severe & widespread infection, numerous blisters

Question 29

what is erythema multiforme that can result from HSV

Answer 29

symmetrical plaques on hands, forearms, feet & lower legs

Question 30

general symptoms of acute HIV infection syndrome

Answer 30

- fever & lymphadenopathy - sore muscles/joints - malaise, loss of appetite & GI symptoms

Question 31

dermatological symptoms of acute HIV infection syndrome

Answer 31

- erythematous maculopapular rash - mucocutaneous ulceration -

Question 32

most common rash seen in HIV

Answer 32

pruritic papular eruption (diagnosis of exclusion)

Question 33

symptoms of pruritic papular eruption

Answer 33

- itchy - discrete scratched red bumps - symmetrical - diffuse - extremities & trunk commonly affected - no mucosa, palmar or webbing involvement

Question 34

steps to treating pruritic papular eruption

Answer 34

- 1st line: steroids, emollients, antihistamines | - 2nd line: phototherapy

Question 35

a thrombosed capillary vessel in warts leads to what appearance

Answer 35

hard surface with black dot in the middle

Question 36

clinical features of common warts

Answer 36

- papules w/ hyperkeratotic, rough surface - back of fingers/toes, nails, knees - cauliflower-like

Question 37

clinical features of plantar warts

Answer 37

- tender - inward growing 'myrmecia' - clusters of mosaic warts

Question 38

clinical features of plane warts

Answer 38

- flat - hands, face, shins - spread by shaving/scratch

Question 39

clinical features of miliform warts

Answer 39

- long stalk | - common on face

Question 40

location of mucosal warts

Answer 40

lips & inside cheeks

Question 41

topical tx for warts and how long does it take to work

Answer 41

- salicylic acid | - 12 weeks

Question 42

cryotherapy tx for warts & how long does it take to work

Answer 42

- freezing wart | - 3-4 months

Question 43

electrosurgery tx for warts and how long does it take to heal

Answer 43

- curettage & cautery

Question 44

RFs molluscum contagiosum

Answer 44

- <10 yo - warm wet overcrowded conditions - atopic eczema - immunocompromised

Question 45

cause & spread of molluscum contagiosum

Answer 45

- poxvirus | - skin2skin, indirect, auto-inoculation, sexual transmission

Question 46

clinical features molloscum contagiosum

Answer 46

- clusters small round papules - white/pink/brown - shiny

Question 47

molluscum contagiosum physical tx

Answer 47

- picking out white core - cryotherapy - laser ablation

Question 48

molluscum contagiosum medical tx

Answer 48

- antiseptic | - wart paint

Question 49

causes of tinea

Answer 49

- ringworm fungus

Question 50

clinical features of tinea

Answer 50

- unilateral & itchy - superficial skin layers - mild

Question 51

6 diff types of tinea according to their location & drug-induced one

Answer 51

- tinea corporis - trunk & limbs - tinea cruris - groin & natal cleft - tinea pedis - athlete's foot - tinea manuum - hand - tinea capitis - scalp - tinea unguium - nails - tinea incognito - corticosteroids, ill-defined lesions, less scaly

Question 52

default for fungal is terbinafine (topical), when to use oral antifungals

Answer 52

severe, widespread/ nail infections

Question 53

why should u avoid topical steroids in fungal

Answer 53

tinea incognito

Question 54

candidiasis RFs

Answer 54

- infant/elderly - warm - high oestrogen/pregnancy - DM - iron deficiency - immunocompromised

Question 55

clinical features of candidiasis

Answer 55

white plaques with erythema

Question 56

what is pityriasis versicolor and what causes it

Answer 56

- yeast infection | - malassezia furfur

Question 57

RFs pitryasis versicolor

Answer 57

- young adults - males - humid - warm environments

Question 58

clinical features of pitryasis versicolor

Answer 58

- hyperpigmented scaly brown patches (can be hypopigmented) - upper trunk - do not tan on sun exposure