Psoriasis Flashcards
most common presentation of psoriatic arthritis
the most common presentation is asymmetric oligoarthritis of the small joints of the hands and
feet.
Where di we find neutrophils in psoriasis skin biopsy ?
The presence of neutrophils in the epidermis, either in
spongiform pustules of Kogoj
or
in microabscesses of Munro
is a typical histopathologic feature of psoriasis, especially acute or pustular forms.
Neutrophils are typically prominent in active lesions and in the marginal zone of expanding plaques, but, in contrast to T ce]]s, they are not a consistent feature of lesionalskin.
Although activated neutrophils could contribute to its pathogenesis, they are not considered to be the primary cause of psoriasis.
ustekinumab and role of cytokines in psoriasis
The striking response of psoriasis to ustekinumab, a human monoclonal antibody against the
p40 subunit of IL-12 and IL-23,
provides additional evidence for the role of cytokines.
Which cell produces IL-23.?
Dendritic cells
Which cytokine whose circuoating levels correlate with disease severity? And why ?
circulating levels of IL-22 correlate with disease severity.
It is thought that IL-23 (produced by DCs) stimulates Th 17 cells to release IL- 17 and IL-22 ; the
concerted action of these cytokines leads to proliferation of keratinocvtes and dermal inflammation (see Fie. 8.1 ).
It has also been proposed that there is a distinct subset of IL- 22-producing T helper cells (Th22 cells) that contribute to the pathogenesis of psoriasis.
Which upregulated pathway explains several phenotypic alterations such as vasodilation (by the induction of iNOS) and accumulation of T cells (via the expression of various chemokines).
The IFN-γ-activated pathway is a key feature of psoriasis.
Which innate immune cytokines are upregulated in psoriatic skin
The innate immune cytokines
IL-l, IL-6 and TNF-a are upregulated in psoriatic skin.
TNF-a is a particularly relevant
cytokine and its importance is underscored by the therapeutic
efficacy of TNF-a inhibitors (see Treatment tg ).
Which chemokine mediates the often-prominent infiltration by neutrophils?
CXCL8
is thought to mediate the often-prominent
infiltration by neutrophils.
Which chemokines are implicated in attracting T cells to the psoriatic plaque.
CCL17, CCL20, CCL27, and CXCL9- 11.
Which chemokine might contribute to the early recruitment of pDCs into psoriatic lesions ?
pDC-attracting chemokine, chemerin,which is increased in psoriatic skin.
Which cells are invooved in innate immune pathways
DCs (myeloid DCs and pDCs) , NK T cells, γδT cells, ILCs, and neutrophils (see above) as well as epidermal keratinocytes.
What is lag time between the trauma and the appearance of skin lesions in koebner phenomenon
usually 2-6 weeks.
can also be induced by other forms of cutaneous injury, e.g. sunburn, morbilliform drug eruption,
viral exanthem.
What is the most common infection provoking psoriasis, and perhaps why ?
Streptococcal infections, especially pharyngitis, are the most common offenders.
In the palatine tonsils of psoriasis patients, immune responses have been shown to be dysregulated, with elevated expression of CLA and the IL-23 receptor.
Streptococci can also be isolated from other sites of infection, e.g. dental abscesses, perianal cellillitis. imnetigo.
True / False
HIV infection has also been shown to aggravate psoriasis
True
Which electrolyte abnormality is associated with generalized pustular psoriasis(trigger) and pustular psoriasis of pregnancy ?
Hypocalcemia
Several drugs have been incriminated as inducers of psoriasis :
in particular lithium, IFNs, beta-blockers, and antimalarials.
Rapid taper of systemic corticosteroids can induce pustular psoriasis as well as flares of plaque psoriasis.
Wioronoff’s ring.
psoriatic lesions are sometimes surrounded by a pale blanching ring, which is referred to as Wioronoff’s ring.
Auspitz sign,
If the superficial silvery white (micaceous) scales are removed, then a wet surface is seen with
characteristic pinpoint bleeding. This finding, called Auspitz sign, is the c]inica] ref]ection of e]ongated vesse]s in the derma] papillae together with thinning of the suprapapillary epidermis.
Compare ibfantile psoriasis with atopic dermatitis
Figure 8.6 B
Infantile psoriasis with a well-demarcated erythematous plaque of the diaper area, along with involvement of the penis and scrotum. This is in contrast to atopic dermatitis where there is often sparing of the diaper area.
Compare ibfantile psoriasis with atopic dermatitis
Figure 8.6 B
Infantile psoriasis with a well-demarcated erythematous plaque of the diaper area, along with involvement of the penis and scrotum. This is in contrast to atopic dermatitis where there is often sparing of the diaper area.
clues to the diagnosis ol psoriatic erythroderma include
previous plaques in classic locations
characteristic nail changes
and central facial sparing.
What are the triggering factors for pustular psoriasis ?
triggering factors include :
pregnancy
rapid tapering of corticosteroids (or other systemic therapies)
hypocalcemia
infections,
and, in the case of the localized pattern, topical irritants.
Impetigoherpetiformis stands for
Generalized pustular psoriasis during pregnancy
Which inherited autoinflammatory disorders have a similar presentation as generalized pustular psoriasis.
The clinical presentation of several inherited autoinflammatory disorders (e.g. DIRA, DITRA,
CARD14-mediated pustular psoriasis, ADAM17 deletion) resembles generalized pustular psoriasis
(see Table 45.7 t@ )52.
