Differential Diagnosis for Erosive Arthritic Changes in Small Joints of the Hand
Single Most Likely Diagnosis
- Psoriatic Arthritis (PsA): This is a strong consideration given the erosive arthritic changes in small joints of the hand, and the absence of RF and anti-CCP antibodies. PsA can present with a variety of manifestations, including asymmetric oligoarthritis, distal interphalangeal joint predominant arthritis, and arthritis mutilans. The lack of RF and anti-CCP antibodies does not rule out PsA, as these are more commonly associated with rheumatoid arthritis.
Other Likely Diagnoses
- Osteoarthritis (OA) with Erosive Changes: While OA is typically non-erosive, there is a subset known as erosive osteoarthritis that can present with erosive changes, particularly in the small joints of the hand. The absence of systemic symptoms and negative serologies (RF and anti-CCP) could support this diagnosis.
- Seronegative Rheumatoid Arthritis: Although less common, some patients with rheumatoid arthritis may be seronegative for both RF and anti-CCP antibodies. The clinical presentation and presence of erosive changes could still suggest this diagnosis, especially if other criteria for rheumatoid arthritis are met.
Do Not Miss Diagnoses
- Hemochromatosis: This genetic disorder leads to iron overload and can cause arthropathy that resembles OA, with potential for erosive changes. It's crucial to consider this diagnosis due to its potential for severe systemic complications if left untreated.
- Gout: Although gout typically presents with acute, episodic arthritis, chronic tophaceous gout can lead to erosive changes in the joints. The absence of RF and anti-CCP does not rule out gout, and it's a diagnosis that should be considered to avoid missing a potentially treatable condition.
- Spondyloarthritis (including Ankylosing Spondylitis and Reactive Arthritis): These conditions can present with peripheral arthritis and may not always have the typical axial symptoms. They are important to consider due to their potential for significant morbidity and the availability of targeted therapies.
Rare Diagnoses
- Multicentric Reticulohistiocytosis: A rare condition characterized by erosive arthritis and skin lesions due to the proliferation of histiocytes. It's an important consideration in the differential diagnosis of erosive arthritis of unknown origin.
- Sjögren's Syndrome with Arthritis: Although more commonly associated with sicca symptoms, Sjögren's syndrome can present with arthritis that may be erosive. The absence of RF and anti-CCP does not rule out this diagnosis, especially if there are other systemic symptoms suggestive of Sjögren's.
- Relapsing Polychondritis: An autoimmune condition that can affect cartilaginous structures, including joints, and lead to erosive changes. It's a rare diagnosis but should be considered in the appropriate clinical context to ensure timely and appropriate management.