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Flashcards in Pyoderma Deck (93)
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1
Q

Pyoderma is almost always….

A

Folliculitis

2
Q

Top 3 causes of folliculitis

A

Pyoderma
Demodex
Ringworm

3
Q

What species is bacterial folliculitis and furunculosis common?

A

Canine

4
Q

What species is cellulitis and abscesses most common?

A

Feline

5
Q

What is folliculitis?

A

Inflammation of hair follicle
Inflammation of superficial epidermis

Note: cats do not get true folliculitis

6
Q

Why do pyodermas develop?

A

Usually secondary to an underlying disease process

Think: allergies or endocrine

7
Q

Resident skin bacteria

A

Staphylococcus sp.
Micrococcus sp.
Streptococcus sp.
Acinetobacter sp.

8
Q

Transient skin organisms

Gram (-)

A

E. coli
Proteus mirabilis
Pseudomonas sp.

9
Q

Transient skin organisms

Gram (+)

A

Staph sp.
Corynebacterium sp.
Streptococcus sp.

10
Q

Transient skin organisms

What do they do?

A

May colonize abnormal skin surfaces

Generally do not penetrate and cause infection directly

May become secondary invaders to Staph (already infected skin; especially deep infections)

11
Q

Pathogenic coagulase positive Staphylococci

Types

A

Staph. pseudointermedius (most common)

Staph. schleiferi (second most common)

Rarely Staph. aureus

12
Q

Pathogenic coagulase positive Staphylococci

Resistance

A

Penicillin

13
Q

What is MRSP?

A

Methicillin-resistant Staph. pseudointermedius

14
Q

Natural barrier to infection

Physical

A

Stratum corneum
Hair

Has normal flora

15
Q

Natural barrier to infection

Physiologic

A

Skin cell turnover rate

Sebaceous gland/Sebum (has antimicrobial properties)

16
Q

Natural barrier to infection

Immunologic

A

Langerhans’ cells (antigen presenting cells; helps prevent infection)
Lymphocytes
Sweat

17
Q

What does pyoderma do to natural barrier functions?

A

Alters it:
Micro-environment of skin (skin folds)
Suppresses immune system (endocrine, steroids)

18
Q

Pathogenic bacteria mechanism

A

Adhere to skin, colonize, and infect abnormal skin

19
Q

Surface pyoderma

What is it?

A

Bacterial overgrowth

Skin erosions (surface irritation or trauma) with secondary adherence and colonization of abnormal skin surface by coagulase positive Staph

No inflammation

NOT folliculitis

20
Q

Skin fold dermatitis

Pathophyisology

A

Surface pyoderma

Anatomical defects create warm moist environment for bacterial adherence and colonization

Accumulation of tears, sebum, urine

21
Q

Skin fold dermatitis

Clinical Sings

A

Surface pyoderma

Erythema
Alopecia
Exudation within skinfolds
\+/- pruritic 
Odor
22
Q

Skin fold dermatitis

Types

A

Surface pyoderma

Facial fold
Lip fold
Vulvar fold
Tail fold
Mammary fold 
Obesity fold
23
Q

Skin fold dermatitis

Diagnosis

A

Surface pyoderma

History
PE
Scrape
Surface cytology (tape, cotton swab, impression) 
Response to treatment
24
Q

Skin fold dermatitis

Treatment (broad)

A

Surface pyoderma

Goal: keep folds dry

If deep lesions present may have to use antibiotics

Do NOT use steroids

Usually: shampoos, wipes, sprays, mousse, ointment

25
Q

Skin fold dermatitis

Treatment: topical antibacteirals

A

Surface pyoderma

Chlorhexidine
Mupirocin ointment
Benzyl peroxide

26
Q

Skin fold dermatitis

Treatment: Antifungal

A

If cytology reveals yeast

Combination products with antibacterials: MalaKet, MiconaHexTriz, etc.

27
Q

Pyotraumatic dermatitis

What is it?

A

Surface pyoderma

Hotspot
Acute moist dermatitis

28
Q

Pyotraumatic dermatitis
Signalment
Clinical Signs

A

Surface pyoderma

Thick coated, long haired
Alopecia
Erythema
Exudation
Ulceration 
Lesion well demarcated from normal skin 
Pruritus
Pain
29
Q

Pyotraumatic dermatitis

Pathophysiology

A

Surface pyoderma

Self trauma
Rule out underlying causes (fleas, allergies, ectoparasites)

30
Q

Pyotraumatic dermatitis

DfDx

A

Demodex

31
Q

Pyotraumatic dermatitis

Diagnosis

A

PE
Skin scraping (rule out demodex)
Cytology
Response to treatment

Note: lesions around face are usually deep lesions and not hotspots

32
Q

Pyotraumatic dermatitis

Treatment (broad)

A

Treat underlying cause (ex. flea control)

Clip and clean

33
Q

Pyotraumatic dermatitis

Treatment: Antibacterials

A

Usually topical
Only have to do systemic antibacterials for deep infections

Chlorhexidine (spray, wipes, shampoo, mousse)
Mupirocin ointment

34
Q

Pyotraumatic dermatitis

Treatment: Antipruritics

A

Topical anesthesia (lidocaine, paramoxine)
Oral steroid
Cytopoint
Apoquel

35
Q

Superficial pyoderma

What is it?

A

Infection restricted to under the stratum corneum or within the ostia of the hair follicles

36
Q

Impetigo

What is it?

A

Superficial pyoderma

Puppy Pyoderma
Infection just beneath stratum corneum of the non-haired areas (axillae and inguinal region)

37
Q

Impetigo

Underlying causes

A

Superficial pyoderma

Parasitism
Viral infections
Dirty environment
Poor nutrition

38
Q

Impetigo

Clinical Signs

A

Superficial pyoderma

Papules, pustules, crusts, epidermal collarettes, crusted papules, hyperpigmented macules

Pruritus variable

Axillae and inguinal regions main affected areas

39
Q

Impetigo

Signalment

A

Superficial pyoderma

Less than 1 year of age

40
Q

Impetigo

Diagnosis

A

Superficial pyoderma

History, PE
Epidermal collarettes!
Skin scraping (rule out demodicosis)
Cytology; neutrophils with cocci
Response to treatment (if it does not respond to treatment think underlying food allergies)
41
Q

Impetigo

DfDx

A

Demodicosis

Dermatopytosis

42
Q

Impetigo

Treatment

A

Can be a self-limiting disease

Topical: chlorhexidine, mupirocin ointment

Systemic anitbiotics for 3 weeks

43
Q

Folliculitis (KNOW)

What is it?

A

Superficial bacterial folliculitis typically referred to as pyoderma

Infection starts in ostia (enterance into hair follicle) and spreads outward under the stratum corneum

44
Q

Folliculitis (KNOW)

Clinical Signs

A

Superficial pyoderma

Papules, pustules, crust!
Epidermal collarettes
Patchy alopecia (mouth-eaten)

+/- pruritus (irritation, usually secondary to underlying disease; allergies, ectoparasites)

45
Q

Folliculitis (KNOW)

Cause

A

Superficial pyoderma

Usually secondary to underlying disease process

Think: allergies or endocrine

46
Q

Papules and pustules think X until proven otherwise

A

Folliculitis

47
Q

Folliculitis (KNOW)

Distribution of lesion

A

Superficial pyoderma

VENTRUM (chest, abdomen)
Axillae
Inguinal region
Focal, multifocal, or generalized

Usually spares legs and head

48
Q

Folliculitis (KNOW)

If pruritus rsolves with antibiotics than…

A

True folliculitis and steroids are contraindicated

Do NOT give steroids until have a diagnosis

49
Q

Folliculitis (KNOW)

Pathophysiology

A

Superficial pyoderma

Something has altered the natural barrier to infection

Frequently secondary to underlying cause (allergies or endocrine)

50
Q

Folliculitis (KNOW)

Pruritic causes

A

Allergies (flea, food, atopy)
Parasites (scabies, chyeletiellosis)
Skin fold

51
Q

Folliculitis (KNOW)

Nonpruritic causes

A

Parasites (demodex)

Endocrine (Hypothyroidism, Cushing’s)

52
Q

Folliculitis (KNOW)

Other causes

A
Chronic steroid administration
Immune dysfunction
Malnutrition
Environmental factors
Frequent bathing
High-humidity
Poor grooming
53
Q

Folliculitis (KNOW)

DfDx

A

Must rule out:
Demodicosis
Dermatophytosis

Others:
Sterile folliculitis (eosinophilic folliculitis)
Autoimmune (pemphigus foliaceus)

54
Q

Folliculitis (KNOW)

Diagnosis

A

Pyoderma = clinical diagnosis

History and PE
Skin scrapings (rule out demodex)
Cytology: neutrophils with or without cocci (taken from intact pustules, crust, epidermal collorette)
Fungal culture; rule out dermatophytosis
Response to treatment (should respond to antibacterials)

55
Q

Folliculitis (KNOW)

Treatment: avoid

A

Do NOT used steroids (or combination products with steroids)

56
Q

Folliculitis (KNOW)

Treatment: Focal

A

Topical: chlorhexidine or mupirocin
2-3 weeks

Shampoos
Medicated wipes
Sprays
Mousse

57
Q

Folliculitis (KNOW)

Treatment: Multifocal

A

Topical

+/- systemic antibiotics

58
Q

Folliculitis (KNOW)

Treatment: Generalized

A

Systemic antibiotics
1-2 weeks beyond clinical resolution! (3-4 weeks total)

Avoid undertreatment; starting to see resistance

59
Q

First Tier Class Antibiotics (KNOW)

When to use them

A

If no prior history of antibiotics used
OR
If previous empirical treatment was effective

60
Q

Beta-lactam Antibiotics

Examples

A

First tier class antibiotics

Cephalexin (1st generation); best choice
Cefpodoxime (Simplicef) (3rd generation)
Cefovecin (Convenia) (3rd generation)
Amoxicillin with clavulante (Clavamox); high dose of 20 mg/kg q12 but should avoid using

61
Q

Folliculitis

Reasons for treatment failure

A
Resistance
Wrong diagnosis (demodex, dermatophytosis, autoimmune) 
Wrong antibiotic or wrong dose
Too short of a course of antibiotics

Failure to identify underlying cause (allergy or endocrine)

62
Q

Folliculitis (KNOW)

Culture?

A

Reconsider DfDx first

When there is no response to first tier or empirical treatment

Deep pyodermas

Cytology reveals mixed infection (rods and cocci)

Immunosuppression

63
Q

Folliculitis (KNOW)

Culture interpretation

A

Make sure you have cultured staphylococcal organism, especially Staph. pseudintermedius or S. schleiferi

Resistance to oxacillin = resistance to methicillin = resistance to beta-lactam antibiotics = MRSP/MRSS

64
Q
Second tier class antibiotics
When to use
A

ONLY use based off of C/S results

65
Q
Second tier class antibiotics
Examples
A
Fluoroquinolones
Clindamycin
TMS
Doxycycline
Rifampin
Amikacin
Chloramphenicol 

If focal try topical; if getting worse give systemic treatment

Must be on antibiotics for 3-4 weeks (must re-check)

66
Q
Third tier class antibiotics 
When to use
A

Should not be used for ethical reasons!

Reserved for humans and treatment of MRSA

67
Q
Third tier class antibiotics
Examples
A

Linezolid

Vancomycin

68
Q

Mucocutaneous pyoderma

What is it?

A

Superficial pyoderma affecting the lips and perioral skin

Usually staph infection

69
Q

Mucocutaneous pyoderma

Clinical Signs

A

Swelling and erythema of lips, especially commissures
Crusting and fissuring may follow
Similar lesions may occur at nares, medial canthus, vulva, prepuce, anus
Hypopigmentation may be seen

Seen most commonly in GSD

70
Q

Mucocutaneous pyoderma

Pathophyisology

A

Unknown!

Does not originate from lip folds

71
Q

Mucocutaneous pyoderma

DfDx

A

Demodicosis
Autoimmune (discoid lupus erythematosus, pemphigus)
Lip fold dermatitis

72
Q

Mucocutaneous pyoderma

Diagnosis

A

PE
Skin scraping
Cytology; bacteria and if not than maybe Lupus
Culture

73
Q

Mucocutaneous pyoderma

Treatment

A

AVOID steroids

Topical antibacterials: mupirocin, chlorhexidine

Systemic antibiotics; 3-4 weeks

Look for underlying disease; allergies or endocrine

74
Q

Deep pyoderma

What is it?

A

Deep infections of deeper regions of the hair follicle, dermis, and subcutis

Includes deep folliculitis/furunculosis and cellulitis

Less common than superficial pyoderma; can occur in conjunction with

75
Q
Deep pyoderma
Diagnostic approach (broad)
A

ALWAYS CULTURE

May be Staph or gram (-) bacteria (Pseudomonas)

76
Q

Furunculosis

What is it?

A

Nodular dermatitis secondary to bacterial infection deep in a hair follicle (deep folliculitis) and subsequent rupture of that follicle (furunculosis)

Rare in cats!

77
Q

Furunculosis

Pathophysiology-Causes

A

Pyodermas are secondary to an underlying disease! Starts superficial than moves deeper

Allergies (flea, food, atopy)
Endocrine (hypothyroidism, Cushing's)
Ectoparasites
Inappropriate use of corticosteroids 
Inappropriate antibiotic therapy
Poor nutrition
Foregin body
Immune dysfunction
78
Q

Furunculosis

Pathophysiology-What occurs

A

Hair follicle ruptures (furunculosis) and releases bacteria, hair, and follicular keratin into the dermis that insights a pyogranulomatous inflammatory reaction

Bacteria present usually Staph. pseudintermedius
Can also be: Proteus, Pseudomonas, E. coli

79
Q

Furunculosis

Clinical Signs

A
Papules
Nodules
Hemorrhagic bullae or vesicles
Draining lesions
Cellulitis
Lymphadenopathy
Systemic illness
80
Q

Furunculosis

DfDx

A
Demodicosis
Fungal infections
Foreign body
Sterile
Neoplasia
81
Q

Furunculosis

Diagnosis

A
History and PE
Skin scraping (rule out demodex)

Cytology:
Pyogranulomatous inflammation
+/- cocci with or without rods

Culture and Sensitivity!
need a sterile punch biopsy; collect with sterile instruments and put in a red top with saline
Do NOT swab surface; not helpful

82
Q

Furunculosis

Kinds

A

Canine acne
Nasal pyoderma
Interdigital pyoderma
Hot spot pyoderma/pyotraumatic folliculitis/furunculosis

83
Q

Furunculosis

Treatment

A

Based on C&S results:
Systemic antibiotics: 6-12 weeks! 2 weeks past clinical remission

Look for underlyin gcuase of pyoderma (allergies? endocrine?)

Topical antibacterial shampoo (chlorhexidine)

84
Q

Canine acne

Breeds

A

Furunculosis

Doberman
Great Dane
English bulldogs
Boxer

85
Q

Canine acne

Location

A

Furunculosis

Chin
Muzzle

86
Q

Canine acne

Cuase

A

Furunculosis

Trauma?
Genetics?
Puberty?

87
Q

Canine acne

Treatment

A

Furunculosis

Topical or systemic antibiotics in more severe cases

88
Q

Interdigital pyoderma

A

Furunculosis

Commonly seen in many disease processes:
Allergic disease
Parasitic disease (Demodex!)
Infectious diseases (fungal)
Endocrine diseases
Sterile (rare)
Foreign bodies (generally rare)
89
Q

Interdigital pyoderma

Lesions

A

Furunculosis

Papules
Nodules
Vesicles
Bullae
Draining lesions
90
Q

Hot spot pyoderma

AKA

A

Pyotraumatic folliculitis/furunculosis

91
Q

Hot spot pyoderma

What causes this?

A

Scratching!

Secondary allergies can be the underlying cause

92
Q

What disorder is caused by dog biting at themselves?

A

Pyotraumatic dermatitis

93
Q

Hot spot pyoderma

Lesions

A

Plaque-like alopecia
“Satellite” papule lesions

Look at ears

Usually seen around face and neck