Summary

Psoriatic arthritis is a seronegative arthropathy occurring in the presence of psoriasis. In majority of cases, typical psoriatic skin lesions precede joint disease, making diagnosis of psoriatic arthritis without typical skin lesions, a diagnostic challenge. Nail lesions are commonly seen in patients affected by this condition, making it a useful clue in the diagnosis of psoriatic arthritis. This is a case of a 58-year-old Filipino woman presenting with sudden acute urinary retention and weakness of both lower extremities accompanied with active polyarthritis. Onycholytic nail changes initially thought to be a fungal nail infection led to the diagnosis of psoriatic arthritis involving the spine. The patient was eventually treated with methotrexate and non-steroidal anti-inflammatory drugs leading to full resolution of symptoms. The patient is currently ambulatory and on regular follow-up. This case report highlights the importance of clinical and physical findings particularly the nails that would lead to a diagnosis of psoriatic arthritis.