Psoriasis – causes, symptoms, diagnosis, treatment, pathology

Psoriasis – causes, symptoms, diagnosis, treatment, pathology

Psoriasis is a non-contagious, chronic autoimmune
disease that causes skin inflammation, and is linked to other autoimmune deficiencies
such as psoriatic arthritis. It can be incredibly itchy and form silver
plaques on the skin that can be embarrassing, and have both physical and psychological effects. Afflicted reality TV star Kim Kardashian,
and singer Cyndi Lauper have each spoken out on how psoriasis can have a significantly
negative impact on the quality of life. Normally, the skin is divided into three layers–the
epidermis, dermis, and hypodermis. The hypodermis is made of fat and connective
tissue that anchors the skin to the underlying muscle. Just above the hypodermis is the dermis, which
contains nerves, sweat glands, lymph and blood vessels. Just above the dermis is the epidermis. The epidermis itself has multiple cell layers
that are composed of developing keratinocytes – which are named for the keratin protein
that they’re filled with. Keratin is a strong, fibrous protein that
allows keratinocytes to protect themselves from getting destroyed when you rub your hands
through the sand at the beach. Keratinocytes start their life at the lowest
layer of the epidermis called the stratum basale, or basal layer, which is made of a
single layer of small, cuboidal to low columnar stem cells that continually divide and produce
new keratinocytes. These new keratinocytes migrate upwards, forming
the other layers of the epidermis. As keratinocytes in the stratum basale begin
to mature and lose the ability to divide, they migrate into the next layer, called the
stratum spinosum which is about 8 to 10 cell layers thick. The stratum spinosum also has dendritic cells
lurking around, which are star-shaped immune cells constantly patrolling for invading microbes
as part of the body’s immune defense system. The next layer up is the stratum granulosum
which is 3 to 5 cell layers thick. Keratinocytes in this layer begin the process
of keratinization, which is the process where the keratinocytes flatten out, and get rid
of their intracellular structures and die, and in the process they create the epidermal
skin barrier. Keratinization leads to development of the
stratum lucidum layer which is 2 to 3 cell layers thick of translucent, dead keratinocytes
that have shed nuclei. The stratum lucidum is only found in thick
skin like on the palms and soles of the feet, because those are the areas that need extra
protection. The stratum lucidum is absent in thin skin,
which covers the rest of the body, and the other layers are thinner. Finally, there’s the stratum corneum, or
the uppermost and thickest layer of the epidermis, which is like a wall of 20-30 layers. As new keratinocytes push up into the stratum
corneum, older dead cells are sloughed off forming skin flakes or dandruff. In this way, the thickness of the epithelium
remains constant with a regulated turn-over of keratinocytes. Normally, there are microbes that live on
the surface of the skin, but when there’s a tiny break in the skin or cut, those microbes
have the ability to enter into the skin layer. At that point, the body notices these ‘foreign
invaders’ and immune cells called dendritic cells capture foreign antigens, break them
down into little fragments that they then present to T-cells. There are two different types of T Cells,
cytotoxic T Cells, which directly kill infected cells, and helper T cells, that help to facilitate
the overall immune response. So, if the dendritic cells present these fragments
and the fragments are recognized by the T-cell, then the T-cell releases cytokines. Cytokines are small proteins used in cell
signaling – such as IL-12, IL- 23, interferon-γ, tumor necrosis factor or TNF, and IL-17, which
specifically has been linked to chronic inflammation. This entire process of inflammation increases
keratinocyte proliferation in the skin. This also recruits other immune cells, like
neutrophils, to the site of infection. Once the microbe is completely destroyed,
the immunologic response slowly returns back to normal. In psoriasis, this immunologic response is
abnormal, and it leads to excessive inflammation. You can think of it as an over-amplification
of the skin’s natural immune process that goes a bit haywire. The causes of psoriasis aren’t clear but
there’s definitely a genetic component and environmental triggers, like trauma, stress,
dietary factors, smoking, or a previous infection. Regardless of how the process is triggered,
once it’s underway it doesn’t shut off, resulting in chronic damage to the skin. In the dermis, inflammation causes the blood
vessels to dilate, particularly at the border between the dermis and epidermis. This allows vessels to circulate and deliver
more immune cells, particularly neutrophils, to the epidermis. In the epidermis, neutrophils collect in the
stratum corneum layer. The inflammation also causes keratinocytes
to proliferate excessively and mature abnormally. The increased keratinocyte proliferation thins
out the stratum basale; but thickens the other layers, particularly the stratum corneum and
stratum spinosum. In fact, as keratinocyte growth outpaces sloughing
off, the cells begin to pile up. These proliferating keratinocytes have a few
maturation defects which are most obvious in the stratum corneum. First, the keratinocytes produce more keratin
than usual causing this layer to become even thicker. Second, the keratinocytes retain their nuclei
– which is called parakeratosis. Third, the keratinocytes don’t adhere to
each other properly, causing breaks in the epidermis. That weakens the skin and makes it more susceptible
to bacteria and viruses, and also gives the skin a scaly appearance. If scales are picked off, the blood vessels
in the dermis can get injured, causing localized spots of bleeding, called an Auspitz sign. Symptoms of psoriasis can vary, and there
are a few subtypes. Plaque psoriasis is the most common. It appears as flattened areas of epidermal
elevation that are inflamed and red or salmon-colored, from the underlying dilated blood vessels,
and are topped with white-silvery scales. Plaques are typically itchy and found on the
scalp and in tensor regions, like the elbows, groin, lower back, and knees. Guttate psoriasis appears as small, red, individual
spots on the trunk and limbs. This subset usually starts in childhood, and
is sometimes triggered by an infection, like a strep throat. Inverse psoriasis appears as smooth and shiny
red lesions that lack scales and typically form within skin folds like in the genital
region, under arms or under the breasts. Pustular psoriasis appears as areas of red
skin with small, white elevations of cloudy pus, formed from dead immune cells. They are usually tender and form on the hands
and feet. Erythrodermic psoriasis is usually the most
severe subset, and appears as fire-red scales that can cover a large area of the skin. They are often extremely itchy and painful
and fall off in large sheets. Psoriatic arthritis manifests as inflammation
in the joints. Nail pitting, shallow or deep holes in the
nails, may appear in any subset. The diagnosis is typically based on the distribution
of the skin damage, and a tissue biopsy can be done to confirm the diagnosis by looking
for classic changes in the epidermal layers. Treatment for psoriasis can include moisturizers
and emollients to help clear psoriatic plaques and minimize itchiness, or may require topical
or systemic immunosuppressive therapies to dampen the immune response. UV phototherapy can also be an option to induce
DNA damage in the keratinocytes and halt their proliferation. New research has been targeting stress management,
dietary intervention, and other immunotherapies to decrease whole body inflammation. For some individuals, there can be significant
feelings of depression or anxiety, especially when there are areas of skin affected by severe
psoriasis. Psychological counselling can help suffers
cope with their condition. In fact, there’s a field called psychodermatology
which utilizes strategies like anti-anxiety medications, biofeedback, allergy and immune
function testing, as well as cognitive behavioral therapy. OK, so, to recap: Psoriasis is an autoimmune
disease that leads to chronic changes in the epidermis due to overstimulation of immune
cells and excessive proliferation of keratinocytes that don’t mature correctly. Psoriasis most commonly causes silvery scaling
of the skin and itchiness. The diagnosis can be made visually, or with
a tissue biopsy. There are various oral and topical treatment
options available, as well as new areas of lifestyle and dietary intervention, and psychodermatology
which addresses the relationship between emotions and physical changes in the skin.


  • Dr M KoKa says:

    Keep it up !

  • Arjun Josephk says:


  • Burak Uzun says:

    Just in time. When taking dermatology rotation and seeing patients every single day who suffer with psoriasis.

  • Viswanadh Dorbhala says:

    well explained …😊

  • sparklyyredshoes says:

    great content. one critique- it sounds like your pronunciation of some of these words is off, maybe those should be check before recording!

  • Mati Imfeld says:

    wow!!! saludos desde argentina!!

  • Aseel H says:

    But in severe cases of psoriasis you can you methotrexate or cyclosporines

  • Ur1z13l says:

    Not very detailed as other videos.

  • Ali ElHowary says:

    where can i get sketches of osmosis videos to study on it !!

  • Abhay Dall says:

    Very nice…missing male voice and sketches like previous videos

  • Abstractism says:

    Very interesting! Reminds me of how beautiful of a machine the human body is.

  • Lanrewaju Okikiolu says:

    Videos here, always brilliant!
    Please note the word GUTTATE, not GLUTTATE, at 6:30.

  • Dayraa Trinidad says:


  • Angelina Bob says:

    Can you please do video on scalp seborrheic dermatitis/cradles crap!?!?! I'm suffering from it and need help, those special shampoos aren't working!!

  • Mohsin Hamza says:

    Thanks osmsis

  • Vardaan Singh Mann says:

    Thank u doc

  • Mr. Yuck says:

    Thank you. I was recently diagnosed with this and found this a better explanation than most sites I’ve looked up.

  • Joseph Magliocca says:

    7:58. The heartbreak of psoriasis

  • harsh singhal says:

    Where's the boy?

  • Taha MD says:

    Perfect Timing. I had like 2 hours to go for the Dermatology Exam xD

  • Billal LAZIRI says:

    thank you very much.
    but how to distinguish between psoriasis and other dermatological illnesses that have the same clinical aspects as psoriasis ?

  • Ali Dalawy says:

    Habibi thank youuuu guys you are amazing 😉😘

  • Lamya Rimas says:

    whatever they said about treatment , believe me doctors lie on you just to buy this chemical treatment for businesses purposes . I tried all chemical treatments but it doesn't works just getting worst day by day …but I use the natural one I overcome the disease

  • FcaminoV says:

    Amazing work, please make atopic dermatitis!

  • Mere Apne says:

    यह एक ऐसा+(whatsaap psoriasis Group)मंच है जहां पर सोरायसिस के जो पेशेंट हैं 10- 15 साल 20 साल से जिन्हें सोरायसिस है  वह अपना एक्सपीरियंस शेयर करते है। अगर आप भी हमारे इस ग्रुप से जुड़ना चाहते हैं जो बिल्कुल मुफ्त है तो आप इस नंबर पे कॉन्टैक्ट कर सकते हैं 

    मोबाइल नंबर 7017254775


    This is a (whatsaap psoriasis group) platform where psoriasis patients are 10- 15 years old who have psoriasis, share their experiences. If you also want to join our group which is absolutely free, then you can contact this number

    Mobile number 7017254775

    Thank you

  • Emre Yavuz says:

    Turkish substitle please nw

  • Prashant Shukla says:

    For dermatology lessons, addition of skin lesion sketch or real photo will make it better

  • TEST TEST says:

    very good

  • Mere Apne says:

    यह एक ऐसा+(whatsaap psoriasis Group)मंच है जहां पर सोरायसिस के जो पेशेंट हैं 10- 15 साल 20 साल से जिन्हें सोरायसिस है  वह अपना एक्सपीरियंस शेयर करते है। अगर आप भी हमारे इस ग्रुप से जुड़ना चाहते हैं जो बिल्कुल मुफ्त है तो आप इस नंबर पे कॉन्टैक्ट कर सकते हैं 

    मोबाइल नंबर 7017254775


    This is a (whatsaap psoriasis group) platform where psoriasis patients are 10- 15 years old who have psoriasis, share their experiences. If you also want to join our group which is absolutely free, then you can contact this number

    Mobile number 7017254775

    Thank you

  • soso free says:

    i miss HIS Voice

  • naruto Punch says:


  • psoriasis treatment .meerut says:

    I have psoriasis treatment 918192006677 my wtsapp number can send me psoriasis pic

  • Angel the Hedgefox says:

    Osmosis I really loved your vids

  • Eva Gold says:

    Why is this form of the nucleus of the denritic cell given?

  • SoundwerK Music says:

    I suffer from psoriasis. It forms on my scalp, and has recently started moving downwards towards my eyebrows and the rest of the upper part of my face.
    I've been looking for stuff that would help me keep it at bay for so many years.
    I recently started using Diprosalic, which contains a adrenocortical hormone.
    That helped me!

  • Manish Arora says:

    My daughter had psoriasis from last 3 years. Now she is taking medication from planet Ayurveda and it is very effective.

  • Santosh Subelal says:

    Make video on heat stroke

  • Fatima AbaAli says:

    Best channel ever 💗

  • saroo Almselatei says:

    Very nice

  • Doug Long says:

    Can you tell me how to make Demi

  • imli wall says:

    Do I have to write about Kim Kardashian and Cyndi lauper??😁

  • Katelyn Lockwood says:

    My psoriasis is getting worse. Feel like I'm losing my mind – absolutely nothing works. No matter what products I use, there is never any difference. Can anyone please recommend a product, something new?

  • Marney Cohen says:

    I use oatmeal for baths…make your own by grinding oats and dilute with water until smooth add to warm bath. Use a cup or more…Also baths with Epsom salts/pink seasalt/baking soda and I've just recently added borax (a natural salt)…this is starting to dry up my spots…I have a bad outbreak and now waiting for light treatment, light is the only thing that clears me completely. I do not use any steroids or pharma prescriptions…been there they do not help in fact they make mine worse…

  • Ahsan Khan says:

    Too fast

  • Bristena T. says:

    This is one of the not so good videos of yours, guys. It would have really used some photos of the lesions. And I don't think you should have insisted so much on the treatment of despression really and so little on the actual treatment of psoriasis.

  • Star Man says:

    I started taking Omega 3 fish oil and in 45 days my psoriasis cleared up completely.

  • Jairos Dancel says:

    The Kardashians be taking over😂

  • Sruthik says:

    I have psoriasis since 2 years and I'm 15 now nobody in my family have it. I get silvery white scales which after some time becomes darkish brown. It's most on my hips but it's spreading to my hands and legs. I'm using olive oil but it's not showing much effect if you people can suggest some thing feel free to do by replying ❤

  • Sneha Yadav says:

    I tried to download osmosis App but it's not working…it downloaded but don't get start only

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