E. Simko WCVM

PTT slides:

http://duke.usask.ca/~els920/

References:General:

Thomson's Special Veterinary Pathology W. W. Carlton et. al.

Special:

Muller & Kirk's Small Animal Dermatology

D. W. Scott et. al

Canine & Feline DermatologyG. H. Nesbitt and L. J. Ackerman

Large Animal Dermatology

D. W. Scott

E. Simko WCVM

Der

mis

Epidermis

Primary hair

Secondary hair

Superficial plexus

Elector pili muscle

Sebaceous gland

Middle plexus

Deep plexus

Sweat gland

E. Simko WCVM

Subcutis

Infundibulum

Isthmus

Inferior segmentHair bulb

Dermal papilla

Hair

Anatomy

E. Simko WCVM

Stratum basale

Basment membrane

Stratum spinosum

Stratum cornium

Stratum granulosum

Hemidesmosomes

Desmosomes

E. Simko WCVM

Anatomy

Anatomy - Epidermis

E. Simko WCVM

Melanocytes

Langerhans cells

Merkel cells

Lymphocytes

Exogenous Factors:

• Infectious• Nutritional• Allergic• Physical• Chemical

Endogenous Factors:

• Immunologic• Hereditary• Congenital• Hormonal• Metabolic• Emotional• Internal dz• Age

E. Simko WCVM

Response to injury

OrthokeratoticHyperkeratosis

• Idiopathic seborrhea• Ichtiosis• Vitamin A deficiency

E. Simko WCVM

• Zinc-responsive dermatosis

• Hepatocutaneous syndrome

E. Simko WCVM

ParakeratoticHyperkeratosis

Response to injury

• Irregular

• Regular

• Papillated

• Pseudocarcinomatous

E. Simko WCVM

Response to injury

Response to injury - Hyperplasia

Pseudocarcinomatous

PapillatedRegularIrregularNormal

Hyperplasia

Atrophy/ HypoplasiaNormal Aplasia

E. Simko WCVM

Response to injury

Hyperpigmentation

• Endocrine diseases• Chronic inflammation

E. Simko WCVM

Der

mis

Ep

ider

mis

Response to injury

Hypopigmentation

• Hereditary/Congenital• Aquired with pigmentary

incontinence

E. Simko WCVM

• Physiologic• Pathologic

(Programmed cell death)

cell death initiating inflammation

E. Simko WCVM

Response to injury

Intercellular (Spongiosis)

Non specific inflammatory

change

E. Simko WCVM

Response to injury

Intracellular Edema

• Vacuolar degeneration• Hydropic degeneration• Balooning degeneration

E. Simko WCVM

Response to injury

Vesicle/pustule formation(Autoimmune dz)

Reticular degeneration(Viral diseases)

E. Simko WCVM

Response to injury

E. Simko WCVM

• Autoimmune dz

• Pyoderma

Response to injury

Acanthocyte

E. Simko WCVM

• Exocytosis

• Pustule

• Crust (serous hemorrhgic, cellular)

Response to injury

E. Simko WCVM

• Atrophy

• Inflammation and fibrosis

• Depositions

Response to injury

E. Simko WCVM

Atrophy

• Physiologic

• Pathologic

Response to injury

Anagen

Telogen

Catagen

Controlled by:

• daylight hours • environment• genetic factors• hormones

Modified from Applied Veterinary Histology, W.J.Banks

Modified from Applied Veterinary Histology, W.J.Banks and Small Animal Dermatology, D.W. Scott

Anagen Telogen

Response to injury

Superficial folliculitis

Deep folliculitis

• Furunculosis• Adenitis

E. Simko WCVM

Response to injury