- It is  common, chronic, disfiguring, inflammatory and proliferative condition of the skin, in which both genetic and environmental influences have a critical role.

The most characteristic lesions consist of red, scaly, sharply demarcated, indurated plaques, present particularly over extensor surfaces and scalp.

Variable in duration, periodicity of flares and extent.

May start at any age but is unusual before the age of 5 yrs.

In China, psoriasis is estimated to affect 0.3% of the population.

Two patterns:-

HLA unrelated- late onset and usually mild.
HLA associated (particularly HLA-Cw6)- early onset and more likely to be severe.


- Genetic
     Psorias has large familial component. 
     Twin studies shows ~80% heritability.
     In monozygotic twins- 1/3rd of pairs will be concordant for Psoriasis.
     Mode of inheritance is genetically complex.
     Susceptible chromosomal area:- HLA region.

- Environmental risk factors
     Interactions between genes and the environment are important in disease causation. Many environmental factors have been linked to psoriasis, and have been implicated in, for example, initiation of the disease process and exacerbation of pre-existing disease.
a) Trauma
Psoriasis at the site of an injury is well known (Koebner phenomenon). A wide range of injurious local stimuli, including physical, chemical, electrical, surgical, infective and inflammatory insults, has been recognized to elicit psoriatic lesions.
b) Infection
Acute guttate psoriasis is strongly associated with preceding or concurrent streptococcal infection, particularly of the throat.
Acute episodes of guttate psoriasis are much more common in individuals
with a family history of plaque psoriasis and one-third of cases of guttate psoriasis progress to the chronic plaque form.
Guttate and chronic plaque psoriasis share strong HLA associations, particularly with HLA-Cw6. 
HIV infection has also been associated with psoriasis.
c) Drugs
There are many drugs reported to be responsible for the onset or
exacerbation of psoriasis. Important ones are lithium salts, antimalarials,    beta-adrenergic blocking agents, non-steroidal antiinflammatory drugs (NSAIDs), angiotensin-converting enzyme (ACE) inhibitors and the withdrawal of corticosteroids.  
Patients with unstable psoriasis should receive appropriate advice before travelling to countries where antimalarial prophylaxis is required.
d) Sunlight
In minority of patients, psoriasis may be provoked by strong sunlight
and cause summer exacerbations in exposed skin. 
Severely photosensitive psoriasis is predominantly female and
strongly associated with HLA-Cw6, family history and very early
age of onset . Photochemotherapy (PUVA) can be helpful in
these patients.
e) Metabolic factors
The early onset of psoriasis in women, with a peak around puberty,
changes during pregnancy and provocation of psoriasis by highdose
oestrogen therapy indicates a role for hormonal factors.
f) Psychogenic factors:- Stress
g) Alcohol and smoking
Alcohol exacerbate pre-existing disease but does not induce psoriasis. M>F. Heavy drinkers have more extensive and inflamed disease.
Smoking also associated with Psoriasis.
h) HIV and acquired Immune deficiency syndrome 
Psoriasis, psoriatic arthropathy and human immunodeficiency virus (HIV) infection are well associated.
The prognosis of acquired immune deficiency syndrome (AIDS) in patients with psoriasis is poor.


a) Keratinocytes hyperproliferation.
Grossly increased mitotic index.
Abnormal pattern of differentiation which involves the retention of nuclei in the stratum corneum.

b) Large inflammatory cell infiltrate comprising polymorphs, T cells and other inflammatory cells.


  - Common sites:knees, elbows, and scalp
  -Gross: well demarcated erythematousplaques with a silveryscale
  - Auspitz sign: removal of scale results in pinpoint bleeding
  - Nail beds show pitting and discoloration


  - Dilated, tortuous papillary blood vessels almost touch the undersurface of the thinning epidermis and are surrounded by a mixed mononuclear and neutrophil infiltrate, as well as extravasated erythrocytes
  - Epidermal hyperplasia 
  - Patchy hyperkeratinization with parakeratosis
  - Uniform elongation and thickening of the rete ridges
  - Thinning of the epidermis over the dermal papillae
  - Munro microabscesses formation


- Stable plaque psoriasis:
    Most common type.
    Individual lesions: few mm to several cms in diameter which are red, dry, silvery white scale.
    Common sites: Elbow, knee and lower back.
    Other sites:
                    Scalp- It is commomly involved.
                               Lesion in the scalp shows well-demarcated easily palpable areas but occasionly shows diffuse, fine scaling making it difficult to distinguish from seborrhoeic dermatitis.
                                Subungal hyperkeratosis
                                Are not scaly but it is red, shiny and symmetrical.
                                e.g psoriasis found in submammary and axillary folds.
                                 It is poorly demarcated and doesn’t look erythaematous so difficult to recognise.
Guttate psoriasis:

This describes the presence of small lesions, appearing generally over the body, particularly in children and young adults, and after acute streptococcal infections. 

In the early stages, there may be little scaling. The lesions are from 2 or 3 mm to 1 cm in diameter, round or slightly oval. They are scattered more or less evenly over the body, particularly on the trunk and proximal part of the limbs, rarely on the soles, not infrequently on the face, ears and scalp. 

Guttate lesions are normally profuse, and in the early stages the colour is not specific.

 The diagnosis is made chiefly on the nature of the scaling, the general distribution and evidence for preceding infection.

Erythrodermic psoriasis:

Skin becomes red or scaly; or occasionly red with little scale.
In some case case of erythoderma, hypo- or hyperthermia may develop d/t problem in temperature regulation.

Pustular psoriasis:

   2 forms

1) Generalised form

Sudden onset with numerous small sterile pustules erupting on a red base.
Pt may rapidly deteriorate with pyrexia coinciding with appearance of new pustules.

2) Localised form
More common.
Affects pamls and soles.
Chronic eruption which comprises small sterile pustules on a red base and which resolve leaving brown macules or scaling.

Pustular psoriasis

- Arthropathy
      Onset: 25-40 yrs

      Chronic RF negative inflammatory arthropathy.

      In pt with current or previous psoriasis

      5 main clinical subtypes:
  symmetrical polyarthritis
  asymmetrical oligoarthritis (large joint)
  severe mutilans


    Explanation, reassurance and instructions.



Topical: - good for single isolated lesions
Tar - based preparations
Vitamin D-analogues
Steroids (rebound)
Dithranol (inhibits mitochondrial DNA)

UV and PUVA therapy:
   - UVR
      For mild to moderate Psoriasis (UVB)

    - PUVA = Psoralen + UV light
      For chronic plaque Psoriasis


    - Useful for multiple lesions, erythrodermic psoriasis, pustular psoriasis
    - methotrexate (hepatic fibrosis, cirrhosis + myelosuppression)
    - cyclosporin (hypertension, renal impairment, immunosuppression)
    - retinoids (good for pustular psoriasis)


  1. Oh my God.. So bad... Haven't tried that but I'm afraid if I will get that.

  2. The pictures on this article are enough to describe the threats and severity of this disease which makes your skin look so ugly.

  3. I can't imagine how those patients fight psoriasis. I hope many would not loss hope fight this disease.

  4. Very informative article. Thank you for sharing. I am currently having psoriasis natural treatment and I hope this will help.

  5. Red, itchy, scaly and irritating skin rashes might cause a great deal of distress for you and if not treated well, it can even result in more rashes and skin damage. Treat your psoriasis completely and feel comfortable after consulting from a board-certified best doctor for psoriasis in Mumbai, Dr. Shoma Sarkar today!

  6. Contact Dr. Deepak Bhalla for Ayurvedic Treatment for Psoriasis. Herbal medicine for Psoriasis without any side affects. Please call +91 9810584818

  7. mbbs in Philippines
    Every year, almost 8000 foreign students take admission in Philippines Medical universities and out of which around 50% are Indian students. The standard of education in Philippines universities is well known around the world. Thousands of doctors from these medical universities are sent to various countries like USA and UK every year. There are around 2299 higher educational institutions and 40 medical colleges. The main benefits of pursuing MD degree from

    Top Medical Colleges in Philippines :


    Top Searched Topics on MBBS in Philippines

    study mbbs in philippines
    philippines medical colleges list
    best medical colleges in philippines for indian students
    philippines medical colleges
    best medical colleges in philippines
    mci approved medical colleges in philippines

    for more information contact us : +91 90329 55688

  8. I would like to say that this blog really convinced me to do it! Thanks, very good post.

  9. UV GULLAS COLLEGE OF MEDICINE is one of Top Medical College in Philippines in Cebu city. International students have the oppertunity to study medicine in phillipines at affordable cost and world class University. The college has successful alumni who have achieved well in the fields of law, business, politics, academe, medicine, sports and other endeavors. At University of the Visayas, we prepare students for a global competition.

    Direct MBBS Admissions Open: 2020-21
    Mobile No: +91 90329 55688
    Apply Now:

  10. MBBS in Philippines Wisdom Overseas is authorized India's Exclusive Partner of Southwestern University PHINMA, the Philippines established its strong trust in the minds of all the Indian medical aspirants and their parents. Under the excellent leadership of the founder Director Mr. Thummala Ravikanth, Wisdom meritoriously won the hearts of thousands of future doctors and was praised as the “Top Medical Career Growth Specialists" among Overseas Medical Education Consultants in India.

    Why Southwestern University Philippines
    5 years of total Duration
    3D simulator technological teaching
    Experienced and Expert Doctors as faculty
    More than 40% of the US returned Doctors
    SWU training Hospital within the campus
    More than 6000 bedded capacity for Internship
    Final year (4th year of MD) compulsory Internship approved by MCI (No need to do an internship in India)
    Vital service centers and commercial spaces
    Own Hostel accommodations for local and foreign students
    Safe, Secure, and lavish environment for vibrant student experience
    All sports grounds including Cricket, Volleyball, and others available for students


Popular Posts