DD- Common Infections and Infestations of the Skin Flashcards Preview

BL/DD USMLE and Basics > DD- Common Infections and Infestations of the Skin > Flashcards

Flashcards in DD- Common Infections and Infestations of the Skin Deck (51):
1

Acquired- breaks in skin/mucosa
20 million+ (US)
–Person-to-person contact
–Fomites

Human Papillomavirus

2

Human Papillomavirus
Virology

Non-enveloped double-stranded DNA
virus

3

Verruca Vulgaris

"Warts"
fingers/lips
From HPV

4

Vulgaris means

Common type

5

Verruca Plantaris

Wart on sole of the foot
From HPV

6

Verruca Plana

flat warts
From HPV

7

Diagnosis of warts

Clinical
• Biopsy
• In-situ hybridization

8

General ways to treat warts

Rev up immune system
Destroy the skin that has the virus

9

Pulse dye laser

Vascular Laser
Decreases blood flow to local area

10

Herpes Simplex Virus
Epidemiology

HSV-1- >90% prevalence by 2

11

Herpesvirus group virus locations

– HSV-1- lips
– HSV-2- genitalia

12

Varicella-Zoster Infection

> 90% of adults have VZV antibodies
Primarily spread by respiratory route
Highly communicable
Causes Chicken Pox

13

Acyclovir traets

herpes
front line rx
short half life

14

Chickenpox

Incubation period- about 14 days

– Fever
– Thin-walled vesicles
-New crops every 3-5 days
– Lesions in multiple stages of development

15

Herpes Zoster is caused by?

VZV!!!!!
-"Shingles"
Herpes only means grouped vessicles

16

Impetigo Epidemiology

superficial bacterial
infection of children
• Acquired by person-to-person contact
• Predisposing factors- high humidity, cutaneous carriage, poor hygiene
* Strep or Staph

17

Streptococcal Non-Bullous Impetigo

Impetigo Contagiosa
-“honey-colored” yellow crust
-affects face
-associated with acute post-streptococcal
-glomerulonephritis

18

Staphylococcal Non-Bullous Impetigo

Frequently a secondary lesion of
superficial injury or dermatitis
yellow to ambercolored crust

19

Cellulitis
Epidemiology

Increased susceptibility:
–Very young
– Elderly
– Immunocompromised
– Intravenous drug users
– Patients with chronic ulcers
Post-surgical complication

20

Cellulitis may show

lymph streaking
needs rx

21

Erysipelas

Cellulitis on the face

22

Can you culture syphilis?

nope

23

Primary syphilis

Incubation- 10-90 days
– Inversely proportional to inoculum's size

24

*Secondary syphilis

Usually seen in clinic
Begins 4-10 weeks after onset of chancre
Diffuse body rash and of palm* and sole*
ORGANISM IS IN THE SKIN

25

Chancre

Non-tender ulcer
• Indurated
• Heals- 3-6 weeks
• Lymphadenopathy

26

Moth-eaten Alopecia

patchy alopecia
2a syphilis

27

Dermatophytes

Fungus- They eat keratin (hair, skin, nails)

28

Tinea Capitis

fungal infection on scalp
May look like a round worm
NO WORM

29

Kerion

area of inflammation induced by the fungus
-purulent
-ABs will not work!

30

Tinea faciei

fungus on face
scaly border

31

Tinea Barbae

Fungus in the beard area (may be caused by shaving)

32

Tinea Corporis

"ring worm"
central clearing
raised edge
NOT A WORM

33

Majocchi’s Granuloma

Hair follicles infected by fungus

34

Interdigital tinea pedis

Fungus on the foot

35

Tinea Pedis Hyperkeratotic
*MOST COMMON

Looks like dry feet

36

Tinea Manum

Fungus on the hand
Just one hand
Comes from the foot usually

37

Two-Feet-One-Hand Syndrome

Tinea Manum + Tinea Pedis Hyperkeratotic

38

Onychomycosis- Subungual

Nail fungus

39

Onychomycosis means?

lifting of nail bed

40

Positive KOH

Highlights the fungus

41

Tinea Pedis- Topical Treatment with ______

Naftifine

42

Affects mucous membranes and skin
• Increased prevalence
– Diabetes mellitus
– Occlusion
–Corticosteroid use
–Broad-spectrum antibiotics
• Found as normal flora
*Preferred food source- glucose or serum

Candidiasis

Can cause all kinds of trouble

43

Candidiasis are usually ______ unlike dermatophyte

inflamation

44

Thrush

Candidiasis causing infection of the mouth

45

More common in humid and warm
climates

Confined to post-pubertal patients

Primarily truncal "V SHAPED"

asymptomatic, tancolored, subtly scaly macule or patch

Tinea Versicolor

• Clinical variants
– Hypopigmented variant
– Folliculitis

46

Scabies

A contagious, intensely itchy skin condition caused by a tiny, burrowing mite

Person to person contact

Inter-digit/ Genital common

47

obligate ectoparasite of humans that causes pediculosis capitis.

Insects spending their entire life on the human scalp and feeding exclusively on human blood.

Head lice

*Very common

48

Body lice is common?

in bad hygiene

49

Creb Lice common in

adult sexually active males

50

Head lice lay their eggs?

an inch away from the scalp on the hair

51

Body lice live on the?

Clothing
Feed on the skin