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Flashcards in Bacterial Skin Disease Deck (45)
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1
Q

What is pyoderma?

A

Bacterial skin infection that can be localised, widespread or generalised

2
Q

In which species is pyoderma most common?

A

Dogs then cats, horses, small mammals, farm animals and birds

3
Q

What is the pathogenesis of pyoderma?

A

All animals have bacteria on skin with the microflora also consisting of opportunistic pathogens and loss of immune defences or break in physical barrier result in pyoderma infection becoming possible

4
Q

What can cause break in skin defences leaving animal susceptible to pyoderma?

A
Skin disease (ectoparasites, allergies, cornification defects, neoplasia, alopecia)
Endocrinopathies, metabolic/nutritional problems
5
Q

What are the main bacteria involved in pyoderma?

A

Staph pseudintermedius/schleiferi/aureus/hyicus
Other gram +ves such as strep
Coliforms, Pseudamonas, Proteus

6
Q

How is pyoderma diagnosed?

A

History, clinical signs, cytology, bacterial culture and search for underlying cause

7
Q

What history fits with pyoderma diagnosis?

A

Recent pyoderma, previous response to antibiotic therapy

8
Q

What clinical signs are seen with pyoderma?

A

Papules, pustules, epidermal collarettes, draining sinuses

9
Q

How can cytology for pyoderma diagnosis be achieved?

A

Impression smear or tape strip stained with DiffQuick or Gram stain

10
Q

How is a bacterial culture to diagnose pyoderma obtained?

A

Swab, crust or tissue

11
Q

What are the three types of pyoderma?

A

Surface, superficial and deep

12
Q

What are examples of surface pyoderma?

A

Hot spot, intertrigo, mucocutaneous pyoderma, bacterial overgrowth

13
Q

What are examples of superficial pyoderma?

A

Impetigo and folliculitis

14
Q

What are examples of deep pyoderma?

A

Furunculosis, chin acne, bacterial granuloma

15
Q

How does pain/pruritis vary with different types of pyoderma?

A

Surface and superficial tend to be pruritic and deep tends to be painful

16
Q

What is intertrigo?

A

Skin folds with surface pyoderma

17
Q

What are the treatment options for intertrigo?

A

Often long term therapy required
Surgical correction if it is a big fold problem
Antibacterial shampoos/creams

18
Q

What is the appearance and pathogenesis of mucocutaneous pyoderma?

A

Looks like cutaneous lupus grossly and histologically

Pathogenesis is poorly understood

19
Q

What does bacterial overgrowth look like clinically and histologically?

A

Very red but no lesions and see lots of bacteria but no neutrophils

20
Q

What is pyotraumatic dermatitis?

A

Acute, can be painful, bacterial invasion causing disruption of stratum corneum often in large breeds due to an underlying pruritic problem

21
Q

What is the therapy for pyotraumatic dermatitis?

A

Topical antibacterial
Anti-inflammatory depending on severity
Treat/correct underlying causes

22
Q

What do you need to be careful not to confuse pyotraumatic dermatitis with?

A

Pyotraumatic folliculitis as this is a deep pyoderma and needs different treatment

23
Q

What is folliculitis?

A

Inflammation of hair follicle

24
Q

What is furunculosis?

A

Deeper inflammation of the hair follicle

25
Q

What is cellulitis?

A

Inflammation extending beyond the hair follicle

26
Q

What is impetigo?

A

Pustules in inter-follicular epidermis affecting young dogs along ventral abdomen that often responds to topical therapy alone

27
Q

What is canine superficial pyoderma?

A

Infection of superficial portion of the hair follicle which is often recurrent and pruritic typically over the ventral abdomen and trunk

28
Q

What causes canine superficial pyoderma?

A

> 90% S. pseudintermedius with 80% caused by endogenous strains

29
Q

What are the typical skin lesions in canine superficial pyoderma?

A

In order of occurrence over time macule, papule, pustule (transient), epidermal collarettes

30
Q

What signs other than skin lesions are also seen in canine superficial pyoderma?

A

Alopecia and pruritis

31
Q

What are the underlying causes of deep pyoderma?

A

Same as superficial pyoderma as well as demodecosis and breed specific immune imbalances

32
Q

What pathogens cause deep pyoderma?

A

60-80% are Staphylococcal

Gram negatives and anaerobes make up the other 20-40%

33
Q

How is deep pyoderma diagnosed?

A

Bacterial culture is always indicated and may have to be from biopsy (don’t put in formalin)
Cytology, skin scrapes, blood tests and imaging for underlying causes

34
Q

What is the therapy for pyoderma?

A

Based on cytology while waiting for culture results and then based on susceptibility testing

35
Q

What skin lesions are seen with deep pyoderma?

A

Haemorrhagic crusts, draining tracts

36
Q

What are the underlying causes for acne in dogs and cats?

A

Often keratinisation defect underlying

Other underlying causes are demodecosis, dermatophytosis, FeLV, FIV and allergies in cats

37
Q

What animals does acne typically affect?

A

Short haired dog breeds as young animals or life long

38
Q

What is the therapy for acne?

A

Systemic treatment to get disease into remission and then topical treatments to maintain disease free state

39
Q

What are the characteristics of acral lick dermatitis?

A

Often large breed dogs with >95% positive bacterial culture

40
Q

How is acral lick dermatitis treated?

A

Long term antibiotics and prevent trauma

41
Q

What are the general treatment options for pyoderma?

A

Antibacterial medication, treatment/correction of underlying causes

42
Q

What are the special considerations for pyoderma therapy?

A

Recurrent, zoonotic implications, antimicrobial resistance

43
Q

How long do pyodermas need to be treated for?

A

Superficial - 3 weeks or 1 weeks beyond complete clinical cure
Deep - 4-6 weeks for 2 weeks beyond complete clinical cure

44
Q

What is dermatophilosis?

A

Branching filamentous actinomycete that mainly affects ruminants and horses and varies in clinical presentations but can have a significant economic impact

45
Q

What are the diseases caused by dermatophilosis?

A

Fleece rot in sheep, mud fever in horses, rain scald in horses