Psoriasis Test
Understating what is Psoriasis and Learning about its main cause, need of diagnosis, different diagnosis methods and management strategies.
Written by Dr Sonia Bhatt
Last updated on 3rd Jul, 2025
Psoriasis is a skin condition that leads to the development of scaly, flaky patches on the skin. On lighter skin tones, these patches are typically pink or red with silvery or white scales. On darker skin tones, they may appear as purple, dark brown, or grey patches, with the scales often looking greyish.
The patches are commonly found on areas such as the elbows, knees, scalp, and lower back, but they can develop anywhere on the body. For most individuals, the condition only affects small areas. However, in some cases, the patches can cause discomfort, including itching or soreness. The severity of psoriasis can differ widely from person to person.
What are the Symptoms and Types of Psoriasis?
Psoriasis is a chronic condition that tends to follow a pattern of remission and flare-ups, where symptom-free periods or mild symptoms are interrupted by more severe episodes.
There are several types of psoriasis, each varying in its presentation and severity:
Plaque psoriasis: The most common form, it is characterised by red, raised patches of skin, often found on the trunk, arms, legs, knees, elbows, genitals, and scalp. Nails may also become thickened, develop pits, or detach from the nail bed.
Guttate psoriasis: Primarily affecting children, this type presents as numerous small, red, raised spots, often following a sore throat.
Pustular psoriasis: This form involves pus-filled blisters, which may cover larger areas of the body or appear in specific regions such as the palms and soles.
As the symptoms of psoriasis can resemble those of other skin conditions, it is important to seek a proper diagnosis.
Consult Top Dermatologist
What is the Need for Testing and How is it Diagnosed?
Several skin conditions, such as eczema, lichen planus, and cutaneous lupus, can cause lesions that may resemble those of psoriasis. To help differentiate between them, a doctor might examine skin cells under a microscope.
Psoriasis is usually diagnosed by a GP or dermatologist through a physical examination of the skin. However, as its appearance can be similar to conditions like eczema, the diagnosis can sometimes be challenging. If symptoms of psoriatic arthritis are present, such as swollen and painful joints, additional tests such as blood tests and X-rays may be performed to rule out other types of arthritis.
A detailed medical assessment typically includes a review of medical history, a physical examination, questions about the impact of psoriasis on daily life, and an evaluation of related health conditions. There are a variety of validated tools used to assess psoriasis, including:
Psoriasis Area and Severity Index (PASI)
Self-Administered Psoriasis Area and Severity Index (SAPASI)
Physicians’ or Patients’ Global Assessment (PGA)
Body Surface Area (BSA)
Psoriasis Log-based Area and Severity Index (PLASI)
Simplified Psoriasis Index
Dermatology Life Quality Index (DLQI)
SKINDEX-16
The severity of psoriasis is typically classified as mild in around 60% of cases, moderate in 30%, and severe in 10%. Assessment of associated health issues may include:
Screening tools for psoriatic arthritis, such as the Psoriatic Arthritis Screening Evaluation (PASE) or Psoriasis Epidemiology Screening Tool (PEST)
Measuring body mass index (BMI) and waist circumference
Blood pressure monitoring
Electrocardiogram (ECG)
Testing for blood sugar levels and glycated haemoglobin (HbA1c)
Evaluations of lipid profile, liver function, and uric acid levels.
Use of Differential Diagnostic and Laboratory Test
To diagnose psoriasis, a dermatologist will typically examine your skin, nails, and scalp for characteristic signs of the condition. They will also ask about any symptoms, such as itching, nail issues like thickening or yellowing, joint problems like pain and stiffness, a family history of psoriasis, or recent life changes, such as illness or increased stress.
In most cases, no specific investigations are required. However, in some instances, further tests may be useful, including:
Skin swabs to identify secondary infections like Staphylococcus aureus and Streptococcus pyogenes
A throat swab to test for beta-haemolytic streptococcus
Skin scrapings and nail clippings to rule out dermatophyte infections
Blood tests (including a full blood count, electrolytes, calcium, and liver function tests) for acutely unwell patients
If needed, the dermatologist may also perform a skin biopsy, where a small sample of skin is removed and examined under a microscope to definitively confirm the diagnosis of psoriasis.
What is the Role of Dermatologists?
Dermatologists will design a treatment plan specifically for your needs, if you have psoriasis. A personalized approach offers several benefits, such as alleviating symptoms like itching, improving the appearance of your skin by clearing or reducing patches, and helping prevent the condition from worsening.
To develop an appropriate treatment plan, your dermatologist will consider:
The type(s) of psoriasis you have
The areas of your body affected by psoriasis
The severity of your condition
How psoriasis affects your daily life
Any other medical conditions you may have
The medications you are currently taking
The main goals of psoriasis treatment are to:
Relieve symptoms, including itching
Improve skin health by removing scales and clearing psoriasis
Address any nail changes, if present
Joint pain reduction in case of psoriatic arthritis
As there is no single treatment that works for everyone, your dermatologist may opt for one treatment or a combination of therapies to achieve the best results.
What are the Treatment Options?
Although there is no cure for psoriasis at present, there are several treatments available that can help control symptoms, allowing you to return to your daily activities and sleep better. Your doctor will collaborate with you to determine the most suitable treatment based on the type and severity of your psoriasis, the areas affected, and the potential side effects of various medications. Treatment options may include the following:
1. Medications
Topical treatments: These include creams, ointments, lotions, foams, or solutions, particularly those containing corticosteroids, which are commonly used for mild to moderate psoriasis. Other topical treatments may include vitamin D-based medications, coal tar, anthralin (tar-based product), phosphodiesterase 4 (PDE4) inhibitors, and drugs that activate the aryl hydrocarbon receptor (AhR).
Methotrexate: A type of antimetabolite medication, available in oral or injectable form that suppresses the immune system and slows down the growth and division of skin cells.
Oral retinoids: These vitamin A-related compounds can be helpful for individuals with moderate to severe psoriasis and are sometimes used in conjunction with phototherapy.
Biologic response modifiers: These injectable drugs target specific immune molecules, helping to reduce or stop inflammation.
Immunosuppressant: Typically prescribed for severe psoriasis, these medications work by dampening the immune response.
Oral phosphodiesterase 4 (PDE4) inhibitors: These target specific enzymes in immune cells to reduce the rapid turnover of skin cells and inflammation.
Oral tyrosine kinase 2 (TYK2) inhibitors: These medications block the activation of certain immune cells involved in psoriasis.
2. Phototherapy
This treatment involves exposure to ultraviolet light, either in a clinical setting or at home with a prescribed ultraviolet light unit. It is generally recommended when large areas of skin are affected by psoriasis.
Tips on living with Psoriasis
Psoriasis can have a significant impact on daily activities, including work and sleep. However, healthcare professionals are aware of the challenges the condition presents and can collaborate with you to help manage symptoms. Along with regular check-ups with your doctor, there are several things you can do to help control your symptoms:
Keep your skin well-moisturised: Use lukewarm water and mild soaps with added oils when bathing. Afterward, apply rich moisturisers while your skin is still damp.
Maintaining a healthy weight: being overweight can worsen psoriasis symptoms
Eat a balanced diet: Research suggests that following a Mediterranean diet may be helpful for managing psoriasis.
Quit smoking: If you smoke, speak to your doctor about creating a plan to stop, as smoking is linked to more severe psoriasis.
Limit alcohol intake: Excessive alcohol can worsen symptoms, so it's important to moderate consumption.
Expose your skin to small amounts of sunlight: Controlled exposure to sunlight can help relieve symptoms, but too much can trigger flare-ups, so it’s important to seek your doctor's advice.
Avoid known triggers: Identify and avoid factors that could provoke flare-ups. Common triggers include stress, cold weather, skin injuries, certain medications, and infections.
Seek emotional support: Consider joining a support group or consulting a mental health professional. Psoriasis can affect self-esteem due to visible patches on the skin, and this may increase the risk of anxiety and depression. Getting support can help you learn coping strategies and improve your well-being.
Consult Top Dermatologist
Consult Top Dermatologist
Dr Ridhima Lakhani
Dermatologist
10 Years • MBBS, MD, DNB
New Delhi
Apollo 24|7 Clinic - Delhi, New Delhi
(25+ Patients)
Dr. K Chetana
Dermatologist
10 Years • MBBS, MD ( Dermatology)
Hyderabad
Apollo 24|7 Clinic, Hyderabad
Dr Ritika Shanmugam
Dermatologist
9 Years • MBBS, MD (Dermatology, venereology, Leprosy)
Bangalore
Apollo 24|7 Clinic - Karnataka, Bangalore
Dr. Manan Mehta
Dermatologist
11 Years • MBBS , MD (Dermatology Venereology , Leprosy)
Gurugram
Avya Skin clinic, Gurugram
Dr. Kavitha Killaparthy
Dermatologist
23 Years • MBBS,DIPLOMA(DERMATOLOGY,VENEREOLOGY,LEPROSY)
Hyderabad
JDS Skin & Hair Clinic, Hyderabad
Consult Top Dermatologist
Dr Ridhima Lakhani
Dermatologist
10 Years • MBBS, MD, DNB
New Delhi
Apollo 24|7 Clinic - Delhi, New Delhi
(25+ Patients)
Dr. K Chetana
Dermatologist
10 Years • MBBS, MD ( Dermatology)
Hyderabad
Apollo 24|7 Clinic, Hyderabad
Dr Ritika Shanmugam
Dermatologist
9 Years • MBBS, MD (Dermatology, venereology, Leprosy)
Bangalore
Apollo 24|7 Clinic - Karnataka, Bangalore
Dr. Manan Mehta
Dermatologist
11 Years • MBBS , MD (Dermatology Venereology , Leprosy)
Gurugram
Avya Skin clinic, Gurugram
Dr. Kavitha Killaparthy
Dermatologist
23 Years • MBBS,DIPLOMA(DERMATOLOGY,VENEREOLOGY,LEPROSY)
Hyderabad
JDS Skin & Hair Clinic, Hyderabad
