Psoriatic Arthritis Without Cutaneous Manifestations: A Case of Diagnostic Delay, Pathologic Progression, and Psychological Burden

Psoriatic arthritis (PsA) is a chronic inflammatory musculoskeletal disease. Presentations can vary, but common manifestations include peripheral arthritis, dactylitis, enthesitis, nail changes, and skin changes, including psoriasis. Diagnosis is often challenging due to the absence of specific biomarkers, variable clinical presentation, and overlap with conditions such as osteoarthritis and fibromyalgia. These diagnostic obstacles contribute to frequent misdiagnosis and delay in treatment, which, over time, leads to irreversible joint damage, functional impairment, and increased comorbidities. A 62-year-old woman with a 15-year history of chronic pain attributed to fibromyalgia and osteoarthritis presented to primary care with persistent hand and foot pain and worsening depressive symptoms. Prior treatments failed to provide relief. Imaging and laboratory evaluation were not consistent with her previous diagnoses of fibromyalgia and osteoarthritis. Although she lacked characteristic psoriatic skin lesions, further history revealed a family history of psoriasis in her daughter and grandson. This finding prompted consideration of PsA, and the diagnosis was made based on clinical presentation and history. The patient was started on disease-modifying antirheumatic drug therapy and escitalopram, with significant improvement in both pain and mood within one month. This case exemplifies the impacts of delayed diagnosis in a patient with PsA without cutaneous manifestations. Common misdiagnoses of PsA can include fibromyalgia, osteoarthritis, and rheumatoid arthritis due to overlapping subjective and objective findings, making diagnosis difficult. This delay leads to prolonged initiation of treatment and thus results in further joint damage, functional decline, and mental health impacts. Quicker suspicion and thorough history taking in patients with chronic musculoskeletal pain unresponsive to treatment could potentially improve diagnostic delay trends of PsA, even in the absence of cutaneous findings.