Lecture: Autoimmune diseases Flashcards Preview

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Flashcards in Lecture: Autoimmune diseases Deck (41)
1

Phemphigus complex

  • Autoimmune
  • antibodies produced against demogleins
    • causes acanthocytic cells
  • type II hypersensitivity

2

causes of pemphigus

  • idiopathic
  • drugs
  • neoplasia

3

Poster child for pemphigus foliaceous

  • butterfly pattern appears on the face
    • symmettrical
    • periocular, bridge of nose

4

P. foliaceous

  • most common type
    • dogs, cats, horses, goats
  • middle aged animal
  • target right below stratum corneum
  • primary lesion: pustule (very transient) starts on face
  • hyperkeratosis feet

5

P. Folaceous in cats

  • face
  • ear pinnae
  • nail bed
  • peri-nipple

*Strippers dz (face, nails, boobs)

6

DDX for PF

  • Superficial pyoderma
  • Dermatophytosis
  • Demodicosis
  • Seborrhea
  • Sterile pustular dz
  • SLE, MF
  • Hepatocutaneous syndrome (NME)

7

PF

DX

  • BX an intact pustule if possible
    • look for acantholytic cells inside the pustule
    • they can be on antibiotics, but NOT STEROIDS

8

Important points PF

  • Rule out pyoderma and deomdex
    • acantholytic cells
    • immunosuppressive therapy contraindicated
  • Make dx first: don't attempt trial therapy
    • waxing and waning dz
    • long-term therapy can have serious side effects

9

Therapy for P. foliaceus

  • high doses of corticosteroids
  • Azathioprine: dogs
  • Chlorambucil: cats
  • Gold

10

Pemphigus erythematosus

about

  • cross over between pemphigus and lupus
  • milder than P. foliaceus
  • antibodies
    • intercellular spaces of epidermis (pemphigus)
    • basement membrane zone (lupus)

11

Clinical signs of P. erythematosus

  • pustular dermatitis
    • face
    • ears
  • nasal depigmentation
  • aggravated by UV light
  • no systemica signs

12

P. erythematosus

DX

TX

  • DX
    • same as PF
    • biopsy, but don't do very often
  • TX
    • mild cases
      • topical steroids or tacrolimus
      • suncreen
    • severe cases
      • immunosuppressive therapy (same as PF)

13

Pemphigus vulgaris

about

  • rare in vet met
  • most common type in humans
  • acantholysis in lower epidermis: more severe lesions

14

P. vulgaris

CS

  • primary lesion is bulla
  • ulcerations and erosions in mouth
  • Animals are very ill
    • lethargy
    • fever
    • anorexia
  • common secondary infections
    • bacterial
    • yeast

15

DDX for PV

  • Drug eruption 
    • Antibiotics
    • seizure meds
  • Mycosis fungoides (cutaneous lymphoma)
  • SLE
  • bullous pemphigoid 
  • contact irritant
  • Burn
  • Candidiasis

16

DX and TX PV

same as all the other pemphiguses

-biopsy areas that have just started, not ser. ulcerated

Prognosis is gaurded to poor

fatal without therapy

17

Pemphigus vegetans

  • very rare
  • mild form of PV
  • Proliferative lesions
  • Scaling, crusting
    • Axillae
    • Groin
  • DX and TX same as PF

18

DIscoid Lupus Erythematosus

  • face and nose
  • aggravated by UV
    • sunlight triggers new antigens

19

Clinical signs of DLE

  • Nose
    • depigmentation
    • loss of normal appearance
    • erosions and ulcerations
  • Pinnae
  • Eyelids
  • Lips
  • Footpads (rare)

20

DDX for depigmented/ulcerated nose

  • Pemphigus
  • Drug eruption
  • Mycosis Fungoides
  • VKH
  • Irritant contact dermatitis
  • Fungal infection

21

DLE

DX

TX

  • Diagnosis
    • histopath if not on steroids
  • TX
    • topical steroids or tacrolimus
    • sunscreens, vit. E
    • systemic therapy
      • steroids (low dose) or
      • tetracycline/niacinamide

22

systemic lupus erythematosus

  • multisystemic disease
  • antibodies produced against different antigens
    • RBC
    • Platelet
    • Nuclear antigens

23

Dermatological signs of SLE

  • Seborrhea
  • Vasculitis
    • necrosis of pinnae and tip of tail
    • footpads crusting and ulceration
  • nasal depigmentation and ulceration
  • mucocutaneous bullous dz
  • panniculitis (lupus profundus)

24

Lupus is a type ____ hypersensitivity

type III

(something about stuff getting stuck in small vessels)

25

DX of SLE

  • take a biopsy
  • baseline blood work
  • ANA

26

SLE

Therapy

  • Immunosuppressive drugs
    • high doses steroids
    • azathioprine
    • chlorambucil

*Gold is contraindicated due to nephrotoxicity

27

Bullous pemphigoid

  • looks like PV without the acantholytic cells
  • antibodies produced against basement membrane

28

BP

CS

  • primary lesion: bulla (very transient)
  • ulcerations
  • fever, anorexia
  • distribution
    • oral cavity
    • axillae and groin
    • mucocutaneous junctions
    • nail beds

29

BP

DX

  • BX close to ulcer
    • need epidermis (no epidermis in ulcer, I think)

30

Erythema Multiforme

  • Immune mediated syndrome
  • usually secondary to drugs or infections
    • cephalosporins
    • TMP-sulfa
    • Levamisole
    • Gold
  • Acute, self-limited
  • usually not systemically ill

31

Clinical signs of EM

  • Target lesions (bulls-eye)
    • Peripheral erythema and central clearing
  • Macules
  • Plaques

32

Erythema multiforme

DX

  • DX
    • History, CS, Histopath
      • apoptotic cells
      • lymphoplasmacytic interface infiltrate
  • Therapy
    • Id underlying cause
    • supportive therapy: antibiotics for the secondary infection
    • Steroids: controversial

33

Toxic Epidermal Necrolysis (TEN)

  • Severe cutaneous eruption
  • Systemically ill 
  • full thickness necrosis and sloughing
  • Mucosal ulcerations
  • Fever
  • lethargy
  • arthralgia

34

TEN

DX

  • DX
    • Histopath (early lesions)
    • Full thickness necrosis
  • TX
    • ID underlying cause
    • supportive care
    • steroids usually contraindicated
  • Prognosis
    • poor (high mortality 80-90%)
      • electrolyte loss
      • secondary infections

35

Mycosis Fungoides (MF)

cancer

  • Cutaneous lymphoma (T cell)
  • Old animals
  • various clinical pres
    • erythema, pruritus and seborrhea

36

Mycosis Fungoides

CS

DX

  • Depigmentation and ulcerations of mucous membranes and nose
    • bad breath
  • Gingivitis
  • Stomatitis and oral ulcerations
  • Plaques and nodules
  • DX
    • Biopsy

37

Necrolytic migratory erythema

  • something about deficiency in amino acids
  • nutritional therapy
  • CS
    • erythema, ulcerations and crusting
      • pinnae
      • muzzle
      • footpads
      • lesions in genitalia are hallmarks
  • secondary bacterial and yeast infection
  • usually borderline diabetic

38

NME

DX

  • Histopath
    • red-white-blue
      • red: hyperkeratosis
      • white: spongeosis
      • blue: hyperplasia of basal layer

39

Not every crusty foot is....

PF

40

Therapy and prognosis for NME

  • ID and correct, if underlying dz
  • Tx secondary infections
  • aminoacid (IV), zinc, fatty acid supplement
  • egg yolk
  • no glucocorticoids
  • poor prognosis

41

Conclusions

  • always treat secondary infections
  • make lists of DDX for all problems
  • correct dx important
    • not everything that looks autoimmune needs steroids
    • BX epidermis before steroids