A 63-year-old man with a 20-year history of severe onychodystrophy and subungual hyperkeratosis presented with a one month of inflammatory arthritis primarily affecting the wrists and hands and left knee enthesitis. In addition to remarkable nail abnormalities, dactylitis was noted in the fingers of the left hand (Picture A). The patient had no history of cutaneous psoriasis.
Inflammatory markers were elevated, while rheumatoid factor and anti-cyclic citrullinated peptide antibodies were negative. The patient was diagnosed with psoriatic arthritis. Methotrexate treatment was initiated.
Joint symptoms, dactylitis, and enthesitis began to improve within three months, and new, healthier nails started to grow. At one year, psoriatic arthritis was in clinical remission, with normalized inflammatory markers. Crucially, severe nail abnormalities and dactylitis showed striking resolution to a normal appearance, as demonstrated in Picture B.
This case emphasizes that severe nail abnormalities can be a strong diagnostic clue for psoriatic arthritis, even in the absence of skin lesions, and that they respond dramatically to effective systemic treatment.
The author states that he has no Conflict of Interest (COI).