1. Introduction
- Definition: Psoriasis is a chronic autoimmune skin condition characterised by rapid skin cell turnover, resulting in thickened, scaly plaques. It is often accompanied by systemic inflammation that can affect other organs.
- Epidemiology: Affects approximately 2–3% of the global population, with no gender preference. The onset can occur at any age, though it commonly develops between ages 15–35.
- Significance: Psoriasis can significantly impact quality of life and is associated with comorbidities like psoriatic arthritis, cardiovascular disease, and depression.
2. Causes and Risk Factors
- Causes:
- Dysregulated immune response involving T cells and cytokines (e.g., TNF-alpha, IL-17).
- Genetic predisposition (HLA-Cw6 gene association).
- Risk Factors:
- Family history of psoriasis.
- Environmental triggers (e.g., infections, trauma, stress).
- Certain medications (e.g., beta-blockers, lithium).
- Obesity and smoking.
3. Pathophysiology
- Immune system activation leads to keratinocyte hyperproliferation, increased skin cell turnover (4–7 days instead of 28 days), and inflammation. This results in the formation of plaques with erythema, scaling, and thickened skin.
4. Symptoms and Features
- Common Symptoms:
- Well-demarcated, red plaques with silvery scales, typically on the scalp, elbows, knees, and lower back.
- Itching, burning, or soreness.
- Types of Psoriasis:
- Plaque Psoriasis (most common).
- Guttate Psoriasis: Small, drop-shaped lesions, often triggered by infections.
- Inverse Psoriasis: Affects skin folds with minimal scaling.
- Pustular Psoriasis: White pustules surrounded by red skin.
- Erythrodermic Psoriasis: Severe, widespread redness and scaling; a medical emergency.
5. Complications
- Psoriatic arthritis, causing joint pain, stiffness, and swelling.
- Increased risk of cardiovascular diseases, metabolic syndrome, and type 2 diabetes.
- Psychological effects, including depression and anxiety.
6. Diagnosis
- Clinical Features: Diagnosis is primarily clinical, based on the appearance and distribution of plaques.
- Histopathology: Skin biopsy may show hyperkeratosis, parakeratosis, and inflammatory infiltrates.
- Severity Assessment:
- Psoriasis Area and Severity Index (PASI).
- Body Surface Area (BSA) involvement.
7. Management Overview
- Goals: Control inflammation, reduce flare-ups, and improve quality of life.
- Approach: Tailored to severity—mild cases may require topical treatments, while moderate-to-severe cases often need systemic or biologic therapies.
8. Treatment Options with Cost (USD)
- Topical Treatments:
- Corticosteroids: ~$10–$50 per tube.
- Calcipotriol (vitamin D analogue): ~$20–$60 per tube.
- Systemic Therapies:
- Methotrexate: ~$30–$60/month.
- Cyclosporine: ~$100–$300/month.
- Biologics:
- Adalimumab: ~$2,000–$3,500/month.
- Secukinumab: ~$5,000–$6,000/month.
9. Advanced Treatment Options with Cost (USD)
- Phototherapy (UVB): ~$50–$150 per session.
- Excimer Laser Therapy: ~$200–$400 per session.
- Biologic Therapies:
- Ustekinumab: ~$5,000–$10,000 per dose.
- Guselkumab: ~$6,000–$7,000 per month.
10. Pharmacological Treatment
- Topical Agents: First-line for mild to moderate psoriasis.
- Corticosteroids: Reduce inflammation and scaling.
- Calcipotriol: Slows keratinocyte proliferation.
- Systemic Agents: For moderate to severe psoriasis.
- Methotrexate: Suppresses immune response.
- Cyclosporine: Reduces inflammation.
- Biologics: Target specific immune pathways (e.g., TNF-alpha, IL-17, IL-23 inhibitors).
11. Medication Tables
Table 1: Doses and Side Effects
Drug | Indication | Dose | Common Side Effects |
---|---|---|---|
Topical corticosteroids | Mild to moderate psoriasis | Apply 1–2 times daily | Skin thinning, striae, irritation |
Calcipotriol | Plaque psoriasis | Apply 1–2 times daily | Skin irritation, hypercalcaemia (rare) |
Methotrexate | Moderate to severe psoriasis | 7.5–25 mg weekly | Nausea, liver toxicity, mouth ulcers |
Adalimumab | Moderate to severe psoriasis | 40 mg subcutaneously every 2 weeks | Injection site reactions, infections |
Secukinumab | Severe psoriasis | 150–300 mg subcutaneously monthly | Upper respiratory infections, headache |
Table 2: Brand Names and Approximate Costs (USD)
Drug | Brand Names | Approx. Cost |
---|---|---|
Topical corticosteroids | Various | $10–$50 per tube |
Calcipotriol | Dovonex | $20–$60 per tube |
Methotrexate | Rheumatrex, Trexall | $30–$60 per month |
Adalimumab | Humira | $2,000–$3,500 per month |
Secukinumab | Cosentyx | $5,000–$6,000 per month |
12. Lifestyle Interventions
- Moisturise skin regularly to reduce dryness and scaling.
- Avoid triggers such as smoking, alcohol, and stress.
- Follow an anti-inflammatory diet rich in omega-3 fatty acids, fruits, and vegetables.
13. Monitoring Parameters
- Disease severity (e.g., PASI or BSA scores).
- Regular blood tests for systemic treatments (e.g., CBC, liver function for methotrexate).
- Monitor for infections in patients on biologics.
14. Patient Counseling Points
- Educate on the chronic nature of psoriasis and the importance of adherence to treatment.
- Emphasise the need for regular follow-ups and blood monitoring for systemic therapies.
- Discuss lifestyle changes to reduce triggers and improve outcomes.
- Provide psychological support to manage the emotional impact of psoriasis.
15. Special Populations
- In Children: Topical treatments like corticosteroids or calcipotriol are preferred; avoid systemic therapies unless severe.
- In Pregnancy: Avoid methotrexate and other teratogenic drugs; use topical therapies or biologics like certolizumab.
- In Elderly: Increased risk of medication side effects; careful dosing and monitoring required.
16. Prevention
- Avoid known triggers, including infections, smoking, and stress.
- Maintain a healthy weight and balanced diet.
- Early treatment of minor flare-ups to prevent progression.
17. FAQs
- What is psoriasis?
Answer: A chronic autoimmune skin condition causing red, scaly plaques. - What causes psoriasis?
Answer: Immune system dysfunction and genetic factors. - How is psoriasis treated?
Answer: Through topical treatments, systemic therapies, or biologics, depending on severity. - Is psoriasis contagious?
Answer: No, it is not contagious. - Can psoriasis be cured?
Answer: There is no cure, but symptoms can be effectively managed. - What triggers psoriasis flare-ups?
Answer: Stress, infections, injuries, and certain medications. - What are biologics for psoriasis?
Answer: Targeted therapies that block specific inflammatory pathways. - How does phototherapy help psoriasis?
Answer: UV light slows skin cell growth and reduces inflammation. - Is diet important for psoriasis?
Answer: Yes, an anti-inflammatory diet can help reduce flare-ups. - Can children have psoriasis?
Answer: Yes, psoriasis can occur in children, often requiring milder treatments. - What is plaque psoriasis?
Answer: The most common form, with raised, red, scaly plaques. - What are the risks of untreated psoriasis?
Answer: Joint damage, cardiovascular disease, and metabolic syndrome. - Can psoriasis affect the scalp?
Answer: Yes, scalp psoriasis is common and can cause severe itching. - How long does it take to see improvement?
Answer: Topical treatments may take weeks; biologics can show results in 2–4 weeks. - When should I see a doctor?
Answer: If symptoms worsen or interfere with daily life.