Plaque psoriasis is the most common form of psoriasis, characterized by raised, inflamed patches of skin covered in silvery scales. It is caused by an immune system dysfunction that causes skin cells to grow too quickly. Risk factors include family history, stress, obesity, and smoking. Diagnosis is usually made through physical exam, and treatments include topical creams and ointments, light therapy, and systemic medications depending on severity.

1. Plaque Psoriasis
YOGESH VISHWAKARMA
ABIGAIL GREAVES
EMMANUEL KINGSLEY

2. What is Psoriasis?
• A chronic condition in which the body makes new cells in 3-7 days rather than 3-
4 weeks
• Red, itchy scaly patches seen on the surface of skin as the cells pile on each
other
• The patches can be seen on various parts of body depending on type of
Psoriasis
• It can be triggered by infections, medications, stress, genetics and trauma

3. What is Plaque Psoriasis?
• Most common form of psoriasis
• The skin can become inflamed, and it can
be covered in plaques
• Plaque is a broad, raised area on the skin
• Most commonly found on the elbow, knees and
scalp

4. Plaque Psoriasis cont’d
• It is autoimmune disease, overactive T cells attack healthy skin and trigger the
production of more skin cells.
• Symptoms such as painful swollen joints and soreness occurs in patients with
plaque psoriasis.
• It is caused by a mutation in the gene CARD14 when it is exposed to an
infection.

5. Risk Factors
• If an individual has a relative with plaque psoriasis.
• A person with HIV can have plaque psoriasis.
• Persons who are obese have a higher chance
of getting plaque psoriasis.
• Persons with high stress also may develop plaque
psoriasis.

6. Anatomy and Physiology of
Cutaneous Membrane

7. • Skin is composed of 3 layers,
Stratified squamous epithelium.
Dense irregular connective tissue
Adipose Tissue

8. Epidermis
• The epidermis is a thin
and most superficial layer
of skin.
• Further epidermis divided
into five separate layers.

9. Epidermis
• Stratum Basale
• It is the layer that’s closest to the blood supply.
• The cells of this layer divide via the process of
mitosis and they form keratinocytes.
• Keratinocytes produce the most important
protein called keratin.

10. Keratinocytes
• It consist 90% - 95% of epidermis layer.
• Life cycle of keratinocytes are around 8 to 10 days from mitosis.
• Skin wound repairing.

11. • Keratin makes our skin tough and provides us
protection from microorganisms, physical harm, and
chemical irritation.
• Two other cell types are found dispersed among the
stratum Basale.
• First is a Merkel cell which functions as a receptor
and second is a melanocyte which produces the
pigment melanin.

12. • Stratum Spinosum
• The stratum spinosum is composed of eight to 10
layers of keratinocytes.
• This layer is a type of dendritic cell called
the Langerhans cell.
• Langerhans functions as a macrophage by engulfing
bacteria, foreign particles, and damaged cells that
occur in this layer.

13. • Stratum granulosum
• This layer has a grainy appearance de to further
changes to keratinocytes.
• Stratum lucidum
• The stratum lucidum is a smooth, seemingly
translucent layer of the epidermis.
• This thin layer of cells is found only in the thick
skin of the palms, soles, and digits.

14. • Stratum corneum
• This is dry and dead layer of skin.
• This layer prevent the penetration of microbes and
dehydration of underlying tissue and provides a
mechanical protection.

15. Dermis

16. Dermis
• Papillary layer
• In the papillary layer are fibroblasts, a small number of fat cells (adipocytes), and
an abundance of small blood vessels.
• The papillary layer contains phagocytes, defensive cells that help fight bacteria
or other infections that have breached the skin.
• This layer also contains lymphatic capillaries, nerve fibers, and touch receptors
which is called the Meissner corpuscles.

18. • Reticular layer
 The reticular layer serves to strengthen the skin and also provides our skin with
elasticity.
 Reticular layer also contains hair follicles, sweat glands, and sebaceous glands.
 Sweat glands regulate our body temperature through the process of
evaporation.
 Sebaceous glands secretes sebum that helps to lubricate and protect our skin
from drying out.

19. Hypodermis

20. Hypodermis
• Subcutaneous layer or superficial fascia is a layer below the dermis and serves
to connect the skin to the fibrous tissue of the bones and muscles.
• This layer consist adipose tissue, which functions as a mode of fat storage and
provides insulation and cushioning.

21. Structures That Contain Keratinocytes
1. Nails
o The nail is a plate like, keratinous,
translucent structure that consists of highly
specialized epithelial cells.

22. 2. Hair
o Hair is made of a tough protein called
keratin.
o The hair follicle serves as a reservoir for
epithelial and melanocyte stem cells.
o It has different color pigments.

23. Physiology/function of the skin
• For protection
• Insulates, waterproof i.e. keratin
• Protects from harsh weather conditions i.e dermis.
• Protects from UV rays
• Regulates body temperature

24. • Helps to synthesis vitamin D
• An organ for sensation
• Also helps to prevent excess water escaping from our
body.

25. Risks factors of plaque psoriasis
• Family history: approximately 30% of all patients with
psoriasis have a close relative who also has the condition
• HIV- Patients with HIV have high risks of plaque psoriasis
compared to people who don’t have.
• Mental stress: high stress levels also increases plaque
psoriasis.

26. • Overweight or obesity: people that are too at have a great chance
of getting plaque psoriasis.
• Regular tobacco smoking: not only is the risk of developing
psoriasis higher, but also its severity.
• Recurring infections: people with recurring infections have a higher
risk of developing psoriasis e.g strep throat.

27. Pathophysiology
• Pathogenesis is not completely understood
• Caused by interactions of leucocytes,
resident skin cells and an array of
proinflammatory cytokines
• Specific factors like genetics or trauma
causes activation of immune cells against the
skin
• This causes thickening and plaque formation
on skin

28. Early Stage
• Unknown factors such as genetics and injury
or trauma causes activation of T cells in lymph
nodes and skin
• These T cells are produced in response to
keratinocyte antigens
• These cells along with dermal dendritic cells
migrate to dermal layer of skin
• Blood vessels dilate and the T cells along with
other immune cells emerge from them

29. • This inflammatory process causes production of various cytokines, e.g. TNF-a
• They accumulate around the basal membrane of epidermis
• These T cells interact with keratinocytes
• They induce proliferation of keratinocytes
• This leads to accelerated cell turnover (from 23d to 3-5d) and improper cell
maturation
• Increased hard and died keratinized cells and decreased stratum spinosum and
granulosum layers
• This causes thickening and hardening of the affected area

30. • Cells in stratum granulosum which normally loses their nuclei,
retain them a condition known as “Parakeratosis”
• Lipids work as cement adhesion between corneocytes
• Epidermal cells fail to release adequate levels of lipids
• This cause poorly adherent stratum corneum leading to flaky and
scaly surface of lesions

31. Later Stages
• It is characterized by acanthosis (thickening of stratum spinosum)
• Psoriasiform hyperplasia which consists of;
• Elongated Rete Ridges
• Suprapapillary thinning
• Dilation of dermal blood vessels
• Parakeratosis becomes confluent and finally granular layer is lost
• Intracorneal collection of neutrophils
• Collection of neutrophils in stratum spinosum known as “Spongiform
Pustule Kogoj’

32. Diagnosis and treatment
Diagnosis
• No special blood tests or diagnostic tests are
needed.
• Physical exam and medical history- by examining
the patient’s skin, scalp and nails.
• Skin Biopsy- A part of skin is removed and
observed under the microscope.

33. Treatment
Treatments can be divided into 3 types
• Topical treatments.
• light therapy
• systematic medications.

34. Topical treatments include…
• Topical corticosteroids
• Prescribed medications for treating mild to moderate
psoriasis.
• Mild corticosteroid creams can be used in sensitive like face,
or skin folds.
• stronger ones are used in areas which are less sensitive or
tough layers.
• using stronger corticosteroid for a longer time can worsen
the condition,

35. Vitamin -D analogues ……..
• These analouges slow down the skin growth.
• Calcipotriene (Dovonex) is a prescription cream
or solution that treats mild to moderate psoriasis
.
• Calcitriol (Vectical) is expensive but may be
equally effective as Calcipotriene
• Less irritating than calcipotriene.

36. • Light therapy [Photo therapy]
the treatment uses natural sunlight or artificial UV
light.
• They include ……..
• Sunlight
• exposure to UV light slows down skin growth
reducing scaling and inflammation.
• exposure to sunlight everyday may improve skin.
• But intense exposure to sunlight may worsen the
condition.

37. • Psoralen plus ultraviolet A (PUVA).
• Photochemotherapy involves taking Psoralen
before exposure to UVA light.
• Then, you are exposed to ultraviolet A (UVA)
light to alleviate your symptoms.
• This more aggressive treatment consistently
improves skin and is often used for more-severe
cases of psoriasis.

38. • Oral or injected medications
• this type of medications are used when psoriasis is resistant to other type of
medications.
• Methotrexate
• Helps the patient by decreasing the production of skin cells and
suppressing inflammation.
• It may also slow the progression of psoriatic arthritis in some people.
• When used for long periods, it causes severe liver damage and decreased
production of red and white blood cells and platelets.

39. • Retinoids
• Contains vitamin A
• This group of drugs help in severe conditions when
other therapies doesn’t work.
• Side effects may include lip inflammation and hair loss.
• Retinoids such as acitretin (Soriatane) can cause
severe birth defects.
• women must avoid pregnancy for at least three years
after taking the medication.

40. References
• Boundless. (n.d.). Boundless Anatomy and Physiology. Retrieved from
https://courses.lumenlearning.com/boundless-ap/chapter/the-skin/
• Erdoğan, B. (2017, May 03). Anatomy and Physiology of Hair. Retrieved from
https://www.intechopen.com/books/hair-and-scalp-disorders/anatomy-and-
physiology-of-hair
• Brannon, H., & Gallagher, C. (n.d.). An Overview of Plaque Psoriasis. Retrieved
from https://www.verywellhealth.com/plaque-psoriasis-overview-1069489
• (n.d.). Retrieved from https://www.nhs.uk/conditions/psoriasis/
• Psoriasis. (2018, March 06). Retrieved from
https://www.mayoclinic.org/diseases-conditions/psoriasis/symptoms-causes/syc-
20355840