L40.5

Clinical Causes: Genetic predisposition, often running in families with a history of psoriasis or psoriatic arthritis. An abnormal immune response where the immune system mistakenly attacks healthy joint and skin tissues. Environmental triggers such as infections, physical injuries, stress, or certain medications that may activate the disease in genetically susceptible individuals. Presence of other autoimmune conditions that could influence immune system activity.

Key Symptoms: Joint pain, often described as aching or soreness, especially in the fingers and toes. Swelling in the joints, leading to a stiff or enlarged appearance. Reduced mobility and stiffness, particularly in the morning or after periods of inactivity. Tenderness around the affected joints. Enthesitis—pain at the sites where tendons or ligaments insert into the bone. Skin symptoms related to psoriasis such as red patches covered with silvery scales, which might appear alongside joint issues. Nail changes like pitting, ridges, or separation from the nail bed.

Diagnosis Path: Blood tests to rule out other types of arthritis and to check for markers of inflammation. Imaging studies such as X-rays, MRI, or ultrasound to assess joint damage or inflammation. Analysis of synovial fluid from affected joints to exclude infections or other joint diseases. Assessment of skin lesions and nail changes consistent with psoriasis. Application of classification criteria, such as the CASPAR (Classification Criteria for Psoriatic Arthritis), to support diagnosis.

Treatment Protocols: Nonsteroidal anti-inflammatory drugs (NSAIDs) to reduce pain and inflammation. Disease-modifying antirheumatic drugs (DMARDs) such as methotrexate or sulfasalazine to slow disease progression. Biologic agents targeting specific immune pathways, like TNF inhibitors, IL-17 inhibitors, or IL-12/23 inhibitors. Topical treatments for skin psoriasis, including corticosteroids, vitamin D analogs, and moisturizers. Physical therapy to maintain joint mobility and muscle strength. Lifestyle modifications such as regular exercise, weight management, and stress reduction to alleviate symptoms and improve overall health. Regular monitoring and follow-up with healthcare providers to adjust treatment plans based on disease activity and response.