Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

Dermatology Board Prep > DERM (21) Vesiculobullous Disease > Pemphigus > Flashcards

Pemphigus Flashcards

1
Q

What are the 5 types of pemphigus?

A
  1. Pemphigus vulgaris (also vegetans)
  2. Pemphigus foliaceus (also endemic, pemphigus-erythematosus)
  3. Paraneoplastic pemphigus
  4. IgA pemphigus
  5. Drug-induced pemphigus vulgaris
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

What are the most common drugs a/w drug-induced pemphigus vulgaris?

A

Captopril and penicillamine

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

Which are stronger, adherens junctions or desmosomes?

A

Desmosomes!

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

What are adherens junctions made up of?

A

Alpha and beta catenins, plakoglobin (intracellular) and cadherens (transmembrane)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

What are desmosomes made up of?

A

Plakoglobin, plakophilin, desmoplakin (intracellular) and desmoglein and desmocollin (transmembrane)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

Describe the desmoglein compensation theory?

A

Basically, there is a gradient of desmoglein 1 and 3 in the mucosal versus epithelial surfaces. In the mucosal membranes, there is more desmoglein 3 mostly with a little bit of superficial desmoglein 1. Therefore, anti-desmoglein 3 antibodies cause lesions in the mucosal surfaces more readily. In the cutaneous epidermis, there is more desmoglein-1 in the superficial parts with little desmoglein 3 so anti-desmoglein 1 antibodies will cause superficial lesions. In the cutaneous epidermis, there is more desmoglein-3 in the deeper basal cell layers with less desmoglein-1 so that is why anti-desmoglein 3 antibodies will cause more lesions in the basal cell layer.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

Where should you biopsy lesions in blistering disease?

A

Edge of the blister for routine H&E and then perilesional skin for the DIF (~1cm away or less)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

What are the recommended substrates for indirect immunofluorescence for Pemphigus Vulgaris?

A

Monkey esophagus (anti-Dsg3)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

What are the recommended substrates for indirect immunofluorescence for Pemphigus Foliaceus?

A

Human skin or guinea pig esophagus (anti-Dsg1)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

What are the recommended substrates for indirect immunofluorescence for Paraneoplastic Pemphigus?

A

Rat bladder (anti-plakin), monkey and guinea pig esophagus (anti-Dsg3 and anti-Dsg1)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

What are the recommended substrates for indirect immunofluorescence for Bullous Pemphigoid, linear IgA?

A

Human skin, salt split skin

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

What are the recommended substrates for indirect immunofluorescence for mucous membrane (cicatricial) pemphigoid?

A

Human skin, salt-split, normal oral or genital mucosa or conjunctiva

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

What is the DDx for hemorrhagic crusts of the vermilion lips?

A

Herpes simplex, herpes zoster, erythema multiforme major, SJS/TEN, pemphigus vulgaris, paraneoplastic pemphigus, contact chelitis

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

Where does pemphigus vegetans favor?

A

The body folds

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

What is the clinical of pemphigus vegetans?

A

Vegetative and papillomatous plaques (pseudoepitheliomatous hyperplasia on pathology) and nodules develop at sites of erosions

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

What is the most common form of pemphigus?

A

Pemphigus Vulgaris (vulgaris means common)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

What is the epidemiology of pemphigus vulgaris?

A

Most common in 50-60 y/o, m=f incidence, Jewish ancestry is at a 10x increased risk

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

What other diseases might Pemphigus Vulgaris be a/w?

A

Myasthenia gravis, thymoma, and autoimmune thyroiditis

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

Which pemphigus type happens in neonates?

A

Pemphigus Vulgaris, the IgG’s if the mother has PV can cross the blood-placenta barrier. The neonate skin is made up of more Dsg-3 like the mucosal skin of adults (more Dsg3 than Dsg1). Thus, neonates don’t get PF.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

What is the appearance of the mucosal lesions in PV?

A

Painful lesions, m/c on the buccal and palatine mucosa w/ irregular borders and different shapes and sizes. You can also get lesions on the conjunctiva, nasal mucosa, vagina, penis, and anus.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

Do the blisters of pemphigus vulgaris cause scarring?

A

No (above the lamina lucida)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

Most common areas of involvement of Pemphigus vegetans?

A

Intertriginous areas > scalp and face

23
Q

What is the evolution of the Pemphigus Vegetans lesions?

A

Early lesions are flaccid pustules rather than vesicles –> erosions–> vegetive/papillomatous plaques.

24
Q

What is the histopathology of PV?

A

Eosinophilic spongiosis is the most common initial finding –> suprabasilar acantholysis without keratinocyte necrosis. You also get “tombstoning” which is vertically oriented basilar keratinoytyes that are attached to BMZ but not surrounding keratinocytes.

The hair follicle is extensively involved.

25
Q

What is the big histologic differential DDx for PV and what are some key distinguishers?

A

Hailey-Hailey disease. Some big differences are the prominent acantholysis of hair follicles seen in PV (Dsg-4), increased eos in PV, the dilapidated brick wall look for Hailey-Hailey, and lack of epidermal hyperplasia in PV can set it apart

26
Q

What is the diagnostic process for PV?

A

DIF is the most reliable test from a perilesional bx. Then you can do an indirect immunofluorescence which can include an ELISA of the pt’s serum which is + in >90% of patients w/ PV. Also you can track this value as it will correspond with disease activity. The best substrate for IIF is monkey esophagus

27
Q

What is the treatment of PV?

A

Oral vs IV CS (think about bowel edema and absorption), steroid-sparing agents (MMF, azathioprine, cyclophosphamide) –> rituximab (it is good to have the pt on pred + MMF vs other immune modulaotr before ritux so as to produce the development of rituximab autoantibody

28
Q

What is the clinical presentation of PF or fogo selvagen?

A

Bullae with “cornflake cereal-like crust”, no mucosal involvement usually, lesions favor the scalp/seborrhea distribution and upper trunk –> can go to erythroderma

29
Q

What if you saw a pemphigus foliaceous type look but only on the face?

A

Think pemphigus erythematosus or Senear-Usher syndrome. Has LE features (blisters around the malar distribution), + ANA in 30% of cases, and mixed PF and SE histology

30
Q

What are the DIF findings of pemphigus erythematosus?

A

ANA + in 30% of cases, DIF same as PF but with granular and linear IgG and C3 at BMZ (Lupus-like look)

31
Q

What is the difference in the epidemiology of folgo selvagem as compared to PV?

A

In endemic areas (Brazil, Tunisia, Finland and Columbia), this is more common than PV. These are caused by black flies in Brazil and causes the disease in children and young adults as compared to older adults for PV.

32
Q

Histologic DDx for PF?

A

PF, pemphigus erythematosus, SSSS and bullous impetigo all show nearly identical findings on H&E (SSSS targets dsg-1 as does PF and pemphigus erythematosus and bullous impetigo).

33
Q

Histopathology of PF?

A

Eosinophilic spongiosis early –> subcorneal acantholysis with darkening of granular cell layer and splits there to the midlevel epidermis.

34
Q

Best substrate for indirect immunofluorescence for PF?

A

Guinea pig esophagus

35
Q

Treatment of PF?

A

Systemic CS +/- dapsone for widespread disease and super potent topical CS for localized disease. You can get epitope spreading to PV, so treat systemically

36
Q

What are the top causes of paraneoplastic pemphigus?

A

Non-Hodgkin’s lymphoma (40%), CLL (30%) >>castleman’s (10 % m/c in children) and thymoma/sarcoma and Waldenstroms macroglobulinemia (6%).

37
Q

What are the antibody targets in paraneoplastic pemphigus?

A

Targeted against all the desmosomal proteins except Dsg-1

38
Q

Clinical differences between paraneoplastic pemphigus and PV?

A
  • Paraneoplastic pemphigus has severe stomatitis w/ extension onto vermillion is the earliest, most common and most persistent sign
  • Can get conjunctival, esophageal, genital and nasopharyngeal lesions too
  • Palms/soles are frequently affected unlike PV
39
Q

Histology of paraneoplastic pemphigus?

A

Overlap between PV, LP, and EM. Suprabasilar acantholysis, vacuolar or lichenoid interface dermaititis, w/ necrotitc keratinocytes, can be buckshot (not seen in PV) and fewer eos.

40
Q

What is the best substrate for indirect immunofluorescence for paraneoplastic pemphigus?

A

Rat bladder

41
Q

What is the diagnostic gold-standard for paraneoplastic pemphigus?

A

Immunoprecipitation/ immunoblotting which detects anti-plakin IgG + anti-Dsg IgG by ELISA

42
Q

Tx and prognosis for paraneoplastic pemphigus?

A

For benign conditions (thymomas and localized Castlemann’s) you can get resolution within 6-18 months after excision

For malignant conditions, it can be really recalcitratnt. Try to treat the underlying malignancy but has up to a 90% mortality rate.

43
Q

What is the most common cause of death in patients with paraneoplastic pemphigus?

A

Underlying malignancy and bronchiolitis obliterans (find with PFT’s and CT/X-ray)

44
Q

How do you distinguish Sneddon-Wilkinson from IgA pemphigus?

A

DIF, this will be negative in Sneddon-Wilkinson

45
Q

What are the 2 types of IgA pemphigus?

A
  1. Subcorneal pustular dermatosis: Desmocollin –> a/w IgA gammopathy
  2. Intraepidermal neutrophilic type (IEN): desmocollin +/- Dsg-1,3
46
Q

What are the clinical differences between the subcorneal pustular dermatosis and intraepidermal neutrophilic type IgA pemphigus’

A

In the SPD type you get pustules in an annular /circinate pattern with central crusting. The most common location is the axillae and groin with no mucosal involvement. This is clinically and histologically indistinguishable from Sneddon Wilkinson’s. You need DIF to tell them apart (+ in IgA pemphigus, SPD subtype)

In the IEN type: Sunflower-like arrangement of vesicopustules

47
Q

What are the histologic findings and DIF findings in subcorneal pustular dermatosis and intraepidermal neutrophilic type of IgA pemphigus?

A
  1. DIF of SPD will show IgA in the upper epidermis, target antigen is Desmocollin 1. Histo you will see subcorneal neutrophilic pustules, acantholysis not usually present
  2. IgA intercellular staining through the entire epidermis, targets are Dsg1/3

Histo you see suprabasilar neutrophilic pustule in the lower to mid epidermis+/- mild acantholysis

48
Q

Presentation and most common drug to cause drug-induced pemphigus?

A

Typically looks like PF (4:1 PF to PV presentation) most commonly triggered by Thiol (sulfhydryl-containing drugs). These include: Penicillamine (50%) Ace-inhibitors captopril>enalapril, lisinopril), arbs, gold

Non-thiol medications are more likely to cause acantholysis by immune mechanisms and are more likely to cause PV-like presentation: beta-lactam, CCBs, beta-blockers, piroxicam, rifampin.

49
Q

What are some medications that can cause drug-induced pemphigus?

A

D-penicillamine, angiotensin-converting enzyme inhibitors, angiotensin receptor blockers, and cephalosporins

50
Q

Where is desmoglein 4 localized to?

A

The hair follicle

Mutated in autosomal recessive localized hypotrichosis and autosomal recessive monilethrix

51
Q

What is pemphigus herpetiformis?

A

Looks like DH clinically, and when biopsied does not show acantholysis generally but rather eosinophilic spongiosis. DIF is + and looks like PF

52
Q

What is the target of the antibody in the superficial pustular dermatosis form of IgA pemphigus?

A

Desmocollin-1

53
Q

What is the most common antigen target for pemphigus vegetans?

A

Desmocollin

54
Q

What is the most common antigen target of IgA pemphigus?

A

Desmocollin

DERM (21) Vesiculobullous Disease (7 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2025 Bold Learning Solutions. Terms and Conditions