Introduction to dermatology Flashcards
What are the 4 main presenting clinical signs in dermatology consultations?
- Pruritis
- Swellings
- Otitis
- Alopecia
What are some of the most common causes of presenting dermatological problems?
- Bacterial infection
- Parasitic
- Neoplastic
- Allergic
- Fungal
- Metabolic
- Immune mediated
What are some of the main dermatological differences between dogs and cats?
- 2ndry bacterial skin infections much more common in dogs
- Cat bite abscess is the most common feline infection
- Primary infections e.g. Dermatophytosis or viral are uncommon, but more common in cats than dogs
- Endocrinopathies are rare in cats although more common in dogs
- Neoplasia more common in dogs
- Parasites and allergy are common in both
What are the benefits of dermatological lesions on the outside of the body?
- Facilitates examination and sampling
- Can monitor treatment response
What are common pitfalls in dermatology consults/therapy?
- Disregarding history
- Failure to appreciate clinical signs
- Not taking a logical, problem oriented approach
- Errors in taking diagnostic samples
- Errors in allergy testing (it is not a diagnostic test, just a means to decide treatment)
- Errors in interpreting results
Give examples of host factors which can influence dermatology
- Age, breed, sex
- Coat colour
- Weight (change)
What are the 3 most common dermatological differentials in cases less than a year old?
- Parasites
- Congenital
- Food induced atopic dermatitis
What are the 3 most common dermatological differentials in adult cases?
- Immune mediated
- Endocrine
- Food induced atopic dermatitis
What are the 3 most common dermatological differentials in elderly cases?
- Neoplastic
- Metabolic
- Food induced atopic dermatitis
West highland terriers are predisposed to which dermatological condidion?
Atopic dermatitis
Males are predisposed to which dermatological problem?
Sertoli cell tumours
Give examples of general history questions to all patients
- Appetite and thirst?
- Vomiting or diarrhoea?
- Number of stools per day?
- Sneezing or conjunctivitis?
- Seasonal history?
- Neurological signs?
- Drug history? Vaccinations?
- Exercise tolerance
- Concurrent disease?
Give examples of questions that should be asked to all patients when obtaining their dermatological history
- Symptoms?
- Onset and duration
- How and when it started, has it progressed?
- Is it itchy?
- Is it seasonal?
- Any previous treatments?
- Does it worsen or improve in certain environments?
What are some examples of chronic dermatological conditions?
Allergies
Metabolic
Endocrine
Neoplastic
What are some examples of acute dermatological conditions?
Parasites
Infectious
Immune mediated
Hypersensitivity
Waxing and waning duration is associated with which dermatological conditions?
Allergic
Immune mediated
Progressive duration is associated with which dermatological conditions?
Metabolic
Endocrine
Neoplastic
Intermittent duration is associated with which dermatological conditions?
Parasites
Infections
A dorso-lumbar itchy distribution indiates?
Fleas
Feet, face, ear pinnae, ventrum +/- perineum itchy distribution indicates?
Atopic dermatitis
Severity of itching is measured using?
The visual analogue scale
- subjective measure of pruritus from 0-10
Atopic dermatitis is seasonally at what time of year?
Summer
Late summer-autumn seasonal itching can be indicative of?
Harvest mites
Steroid treatment commonly causes which adverse effect?
Excessive drinking
What factors need to be considered when asking an owner about flea treatment?
- Product(s)
- Frequency
- Last application
- In contact-animals?
What is a primary dermatological lesion?
- Initial eruption develops spontaneously due to underlying disease e.g. papule or pustule
- Usually transient
- Sample to aid diagnosis
What is a secondary dermatological lesion?
- Evolve from primary lesions or external factors e.g. crust evolves from a pustule
- May help with diagnosis
How many layers make up the epidermis?
4
What are the main cells in the epidermis?
Keratinocytes
What are some of the main anatomical features of the dermis?
- Blood vessels & nerves
- Hair follicles
- Sebaceous glands
- Sweat glands
Give some examples of primary lesions
- Pustule
- Papule
- Papular-macular rash
- Alopecia
- Erythematous plaques
Give some examples of secondary lesions
- Lichenification (thick, leathery skin)
- thinned skin
- crusts and erosions
- Epidermal collarettes
- Scale
- Ulcers
- Comedones
What do Epidermal collarettes look like?
Rim of scale around a circular lesion
Occur secondary to pustules
Scale occurs secondary to?
Chronic inflammation
What are Comedones?
Pores or hair follicles that have gotten blocked with bacteria, oil, and dead skin cells to form a bump on your skin (like a black head)
What is lichenification?
Thickening of all skin layers in response to chronic inflammation
What are erosions?
Loss of epidermis above basement membrane
What are ulcers?
Loss of epidermis through the basement membrane into the dermis
Superficial bacterial pyoderma contains a mix of which primary and secondary lesions?
- Papules
- Pustules
- Crusts
- Epidermal collarettes
- Pigmented macules
A bilateral symmetrical dermatological distribution indicates? give an example
Inside out disease e.g. atopic dermatitis
An irregular distribution of dermatological disease indicates? give an example
Outside-in disease e.g. Dermatophytosis
What needs to be considered when performing a hair coat examination?
- Change in colour?
- Change in texture?
- Easily epilated? e.g., telogen?
- Broken hairs - self trauma?
- Follicular casts?
What is a Follicular cast?
An accumulation of keratinous debris around the hair shaft seen protruding from the follicular ostium or present when hairs are plucked and examined. Indicates a defect of follicular keratinisation.
If follicular casts are found which 4 conditions are indicated?
Demodex
Pyoderma
Malassezia
Sebaceous adenitis
For each lesion found which 4 parts of it need to be described?
- Configuration
- Morphology (primary/secondary)
- Distribution
- Evolution
