Nodular Dermatoses

Question 1

What diagnostics approach should you use to nodules ?

Answer 1

Cytology - FNA of nodule and regional lymph node

Impression smear — any discharge or ulcerated lesion

Biopsy
Culture may be indicated based on cytology

Question 2

What is the differential diagnosis for nodules?

Answer 2

Inflammatory

• infectious
• sterile nodular disease
• cysts

Neoplasia

• benign
• malignant

Question 3

What is the dog of papillomatosis?

Answer 3

Papilloma virus or idiopathic

Viral: lesions can be transmitted

Question 4

Signalment associated with papillomatosis?

Answer 4

Young or immunosuppressed

Cutaneous: usually solitary; smooth to papilliferous

Inverted papilloma
Pigmented plaque

Question 5

What is the DDX for papillomatosis?

Answer 5

Neoplasia 
Collageous nevi 
Granulation tissue 
Eosinophilic granuloma 
Inclusion cyst

Question 6

What is the treatment for papilloma

Answer 6

Some progress
Crushing
Laser or cryotherapy
Azithromycin: 3 wks course

Topical imiquimod - prevents licking
Interferon
Surgically excise a persistent or compromising lesions

Question 7

What are causes of nodular panniculitis or steatitis?

Answer 7

Infectious

Non-infectous

• vaccine
• trauma
• foreign body
• nutritional deficiency
• pancreatic dz
• immune mediated disease
• idiopathic

maker of systemic disease

Question 8

Most common location for nodular panniculitis or steatitis?

Answer 8

Dorsal trunk, neck, and prox limbs

Question 9

Treatment for a sterile pyogranuloma?

Answer 9

Corticosteroid
Tetracycline + niacinamide
Azathioprine
Cyclosporine A

Question 10

What are the forms of histocytic proliferative diseases?

Answer 10

Histiocytoma 
Cutaneous histiocytosis 
Systemic histocytosis
Malignant histocytosis 
Histocytic sarcoma

Question 11

How does a hitocytoma appear? How can you diagnose?

Answer 11

Round, alopecic red

Grows fast (days to weeks, remains that size)

Aspiration cytology is often diagnostic
Will regress over a few weeks

Question 12

What is feline proliferative histiocytosis? Where is it generally locate?

Answer 12

Single to multiple, firm papules, nodules, plaques.
Non-pruritic

Legs, feet, face

No treatment helpful

Question 13

What is nodular dermatofibrosis? What breed is it most common in?

Answer 13

Multiple cutneaous nodules of mature collagen hyperplasia

GSD (3-7yrs)

Question 14

T/F: nodular dermatofibrosis is secondary to underlying disease

Answer 14

True

• has been associated with bilateral renal cysts, cystadenomas, and cystadenocarcinomas

Question 15

Clinical signs of juvenile cellulitis?

Answer 15

Looks lie pyoderma pulsates

Swelling of face, submandibular
Lips, muzzle, and eyelids

Non-cutaneous signs

• lethargy, pyrexia, anorexia
• 25% have suppurative arthritis

Question 16

What are key rule outs for juvenile cellulitis AKA puppy strangles?

Answer 16

Demodex
Deep bacterial pyoderma
Angioedema

Question 17

Diagnosis of juvenile cellulitis ?

Answer 17

Cytology: pyogranulomtous

Biopsy: (pyo)granulomatous dermatitis/cellulitis, no infectious organisms

Culture- sterile

Question 18

What is the treatment for juvenile cellulitis ? Prognosis ?

Answer 18

Topical - remove crust

Systemic

• pred (every 24hrs until remission then EOD for 2-3weeks)
• prophylactic antibiotic

Good if treated early, avoids scarring

Question 19

When does a cyst develop?

Answer 19

When a hair follicle or skin pore gets blocked by dirt, debris, scar tissue, or infection

Question 20

T/F: both sebaceous cysts should be manually expressed?

Answer 20

False

Manual expression of keratin cysts can cause subepidermal rupture and subsequent furunculosis

Question 21

Treatment of sebaceous cysts?

Answer 21

Excision is curative

Prevention: benzoyl peroxide shampoo
Retinoids therapy

Question 22

T/f: Lipomas should be removed surgically?

Answer 22

Kinda false, kinda true

They are benign but if they start to grow, they can be surgically removed

Question 23

What is diagnostic for lipoma?

Answer 23

Aspiration cytology

Question 24

Clinical signs of fly bite dermatitis?

Answer 24

Biting flys: tips of ears- erythema, bleeding, oozing, crusting

Tumbu flies: tail base, ventral abdomen - painful, reddened nodule

Question 25

What species of fly causes a maggot infestation, forms nodules on the skin with a well circumscribed hole in center?

Answer 25

Cobylobia anthrophaga (tumbu/mango fly)

Question 26

Treatment fo myiasis?

Answer 26

Topical fly repellants

If maggots

• clip and clean
• flush out maggots
• adjunct ivermectin

Tumbu flies

• cover breaking holes with Vaseline (die)
• squeeze out if problematic