3. Examine the skin of the horse and summarise the findings. Explain how to take skin biopsies from horses

Question 1

Name the main steps to set a dermatological diagnosis

Answer 1

1. chief complaints (Why the owner is reaching out)
2. Signalement
3. Medical history and dermatological history
4. Physical examination
5. Differential diagnosis
6. Therapeutic plan
7. Secondary diagnositc method
8. Trial period
9. Narrowing differential diagnosis

Question 2

What do we find/check for during the physical examination?

Answer 2

1. Basic clinical values
2. We look for skin lesions, both primary and secondary

Question 3

Name some primary lesions:

Answer 3

1. macule
2. Vesicule
3. Papule
4. Pustule
5. Nodule
6. Tumour
7. Cyst
8. Urticaria

Question 4

Name some secondary lesions:

Answer 4

1. Alopecia
2. Scaling
3. Crusting
4. Scar
5. Erosions
6. Ulcer
7. Fissure
8. Lichenification
9. necrosis

Question 5

Name some secondary diagnostic methods:

Answer 5

1. Haematology
2. Biochemistry
3. Skin scraping
4. Hair and follicle sample
5. Brushing
6. Cellotape
7. Swab, aspiration, impression smears
8. Biopsy

Question 6

skin scraping, why?

Answer 6

Parasite disease.

Not really suitable for bacterial and fungal culture

Question 7

Cellotape, which parasite?

Answer 7

oxyurosis, around anus

Question 8

Swab, aspiration, impression smears, why and what?

Answer 8

fungi, bacteria, parasites (Habronema), cytology

Question 9

Name different types of skin biopsy:

Answer 9

1. Shave
2. Punch
3. Wedge
4. Excisional

Question 10

Indications of skin biopsy:

Answer 10

1. To establish a specific diagnosis
2. To rule out differential diagnoses
3. To follow the course of the disease
4. To confirm the completeness of tumor excision

Question 11

Explain how to perform a skin biopsy:

Answer 11

1. Most cases: pinch biopsy is enough
2. 6mm - diameter punch needle is used
3. Skin disinfection + injection of local anaesthetic
4. Biopsy punch is rotated with firm pressyre to penetrate the skin, down to subcut. tissue.
5. Skin is removed using forceps and blade
6. suture of non-absorbable material - 2.0 prolen

Question 12

Explain how to perform a skin biopsy, or larger area:

Answer 12

1. Excision might be necessary
2. Include some normal skin at the periphery of the lesion
3. fixative for skin biopsy: 10% buffer formaline
   4.

Question 13

Which lesions is not possible to obtain skin biopsies from, why?

Answer 13

1. Tumours
2. Pemphicus foliaceus

findings might be rather general, not specific.

Question 14

How to perform a wedge biopsy:

Answer 14

1. Anaesthesise the skin
2. Stab incision in a V shape with a scalpel
3. Lesion is left to heal by secondary infection

Question 15

How to perform a excisional biopsy:

Answer 15

1. General anaesthesia
2. Small incision of skin
3. X-ray or ultrasound to confirm the abnormal area is within the removed tissue

Question 16

How to perform a shave biopsy:

Answer 16

1. thin piece of skin is removed from the surface - with a sharp blade.
2. Skin is examined under a microscope