Psoriasis

Signs and symptoms

The manifestations vary with type and gravity, but the most recognisable signs are:

• Well-defined red plates, covered by silver-white scales.
• Typical locations — elbows, knees, scalp, lumbar region.
• Itch — not always present, but often.
• Nail changes — punctiform depressions, thickening, detachment (onycholysis).
• Painful fissures in flexion zones or thick plates.
• Sensation of pruned skin, especially in the most affected areas.
• Auspitz sign — small bleeding points when removing scales (should not be done on purpose).

Types of psoriasis

Psoriasis may present in several patterns, with distinct implications for treatment:

• Plaque psoriasis (vulgar) — the most common pattern with well-defined plaques.
• Psoriasis gutata — small gout-shaped lesions, often after a throat infection.
• Inverse psoriasis — in fold zones (axillae, groins, under the breast), without evident scales.
• Pustular psoriasis — lesions with sterile pustules (localised or generalized).
• Erythrodermal psoriasis — involvement of almost all body surface (rare, requires urgent evaluation).
• Nail psoriasis — predominant or exclusive nail involvement.
• Psoriasis of the scalp — very common, with plaques covered with thick scales.

Causes

Psoriasis is a multifactorial disease in which genetic, immune and environmental factors interact:

• Genetic predisposition — various associated genes; family history in about 30-40% of cases.
• Immune dysfunction — exaggerated inflammatory response mediated by cells T and specific cytokines.
• Accelerated turnover of skin cells — epidermal renewal that usually takes 28 days is done in 3-5 days.
• Environmental factors that trigger or aggravate outbreaks in those with predisposition.

Frequent triggers

Not all patients recognise clear triggers, but some are well established:

• Infections — mainly streptococcal pharyngitis (associated with gutata form).
• Intense emotional stress.
• Certain medicines — to be discussed with the doctor before starting or stopping any therapy.
• Skin trauma (Koebner’s phenomenon — lesions appear in areas of wound or irritation).
• Consumption of alcohol and smoking:
• Cold, dry air and lack of controlled sun exposure.

Diagnosis

The diagnosis is clinical, made by the evaluation of lesions, typical distribution and family history. No routine tests required.

In an online consultation, the dermatologist analyzes photographs of the affected areas and a questionnaire on evolution, treatments already experienced and family history. With this information classifies the type, evaluates the extension and defines a custom plan.

In doubtful situations or when it is necessary to distinguish from other dermatoses, a skin biopsy — which requires face - to - face evaluation — may be recommended.

Options for treatment

Psoriasis is chronic but responds well to treatment. The aim is to reduce the extent of injuries, relieve symptoms and maintain long periods of remission. The strategy depends on severity, affected locations and impact on the patient's life.

Regardless of the strategy, supportive care — daily hydration, trigger management, comorbidity control — is part of the plan.

Beyond the skin

Psoriasis is a systemic disease, not only cutaneous. Some patients develop other manifestations that should be evaluated and monitored:

• Psoriatic arthritis — joint pain, stiffness and inflammation; may precede or accompany skin lesions.
• Increased cardiovascular risk — to be discussed with the family doctor.
• Association with metabolic syndrome, obesity and insulin resistance.
• Significant psychological impact — anxiety and depression are common and should be addressed.

Frequently asked questions