[drmodi44]

A 61-year-old woman develops a severe skin disease characterized by multiple oral ulcers and flaccid bullae that rupture easily on her scalp, face, and trunk with Positive Nikolsky sign. Autoimmune attack on which of the following structures is thought to contribute to the pathophysiology of this disease?

(A) Actin microfilaments
(B) Desmosomes
(C) Gap junctions
(D) Microtubules
(E) Tight junctions​

 

[smart-g]

A "positive" Nikolsky's sign is associated with pemphigus vulgaris . The pathogenesis of the disease involves autoantibodies against desmosome proteins, separating keratinocytes from the basal layer of the epidermis. So the answer is B)

 

[rajat13]

B) Desmosomes
Against Desmoglein

Most probable Dx is Pemphigus vulgarism which has antibodies against Desmoglein 3..
Why??

1. Age
2. oral mucosa involvement
3. flaccid bullae (superficial separation in epidermis)
4. positive Nikolsky Sign

 

[ecgram]

positive nikolsky is seen in bullous pemphigoid isnt it ???

 

[drmodi44]

yup its B

yup..its a case of Pemphigus vulgaris

IgG antibodies develops against intercellular attachment sites (desmosomes) between keratinocytes ......​

 

[rajat13]

Nikolsky's sign is particularly useful in differentiating pemphigus vulgaris, which causes a positive sign, from bullous pemphigoid, in which the sign is usually absent.

If referring to Goljan's RR, the statement in the book is wrong and interchanged.
GIVEN:
Nikolsky Sign positive in Bullous Pemphigoid and negative in Pemphigus Vulgaris.

ACTUALLY:
Nikolsky Sign negative in Bullous Pemphigoid and positive in Pemphigus Vulgaris.

The reason for this reaction is a weakening relationship and contact between the corneal (horny) and granular layers on all surfaces, even in places between lesions on seemingly unaffected skin. This happens only in Pemphigus. Whereas in Bullous Pemphigus is an autoimmune disease against hemidesmosomes, BP Ag 1 and 2 (BP stands for Bullous Pemphigoid).

I hope that helps.
​

 

[khanar]

Related thread

Have a look here
http://www.usmle-forums.com/usmle-s...47-nikolskys-sign-differential-diagnosis.html

 

[ecgram]

thanks alot