- Joint swelling (HP:0001386). Evidence: PCS. (PMID:27156434)
- Elevated erythrocyte sedimentation rate (HP:0003565): An increased erythrocyte sedimentation rate (ESR). The ESR is a test that measures the distance that erythrocytes have fallen after one hour in a vertical column of anticoagulated blood under the influence of gravity. The ESR is a nonspecific finding. An elevation may indicate inflammation or may be caused by any condition that elevates fibrinogen. Evidence: PCS. (PMID:27156434)
- Polyarticular arthritis (HP:0005764). Evidence: PCS. (PMID:28723028)
- Joint stiffness (HP:0001387): Joint stiffness is a perceived sensation of tightness in a joint or joints when attempting to move them after a period of inactivity. Joint stiffness typically subsides over time. Evidence: PCS. (PMID:27156434)
- Rheumatoid arthritis (HP:0001370): Inflammatory changes in the synovial membranes and articular structures with widespread fibrinoid degeneration of the collagen fibers in mesenchymal tissues, as well as atrophy and rarefaction of bony structures. Evidence: PCS. (PMID:28723028)
- Fatigue (HP:0012378): A subjective feeling of tiredness characterized by a lack of energy and motivation. Evidence: PCS. (PMID:9652497)
- Elevated circulating C-reactive protein concentration (HP:0011227): The concentration of C-reactive protein in the blood circulation is above the upper limit of normal. Evidence: PCS. (PMID:27156434)
- Digital flexor tenosynovitis (HP:0012276): Inflammation of the flexor digitorum tendon, often associated with the Kanavel signs: (i) finger held in slight flexion, (ii) fusiform swelling, (iii) tenderness along the flexor tendon sheath, and (iv) pain with passive extension of the digit. Evidence: PCS. (PMID:28723028)
- Swan neck-like deformities of the fingers (HP:0006150): A swan neck deformity describes a finger with a hyperextended PIP joint and a flexed DIP joint. The most common cause for a swan neck-like deformity is a disruption of the end of the extensor tendon. Conditions that loosen the PIP joint and allow it to hyperextend, for example conditions that weaken the volar plate, can produce a swan neck deformity of the finger. One example is rheumatoid arthritis. Another cause are conditions that tighten up the small (intrinsic) muscles of the hand and fingers, for example hand trauma or nerve disorders, such as cerebral palsy, Parkinson's disease, or stroke. Evidence: PCS. (PMID:28723028)
- Arthralgia (HP:0002829): Joint pain. Evidence: PCS. (PMID:27156434)
- Anti-citrullinated protein antibody positivity (HP:0033034): The presence autoantibodies in the serum that react do different citrullinated antigens, including filaggrin, fibrinogen, vimentin and collagen. Evidence: PCS. (PMID:28723028)
- Interphalangeal joint erosions (HP:0006252). Evidence: PCS. (PMID:28723028)
- Fever (HP:0001945): Body temperature elevated above the normal range. Evidence: PCS. (PMID:9652497)
- Weight loss (HP:0001824): Reduction of total body weight. Evidence: PCS. (PMID:9652497)
- Rheumatoid factor positive (HP:0002923): The presence in the serum of an autoantibody directed against the Fc portion of IgG. Evidence: PCS. (PMID:28723028)
- Vasculitis (HP:0002633): Inflammation of blood vessel. Evidence: PCS. (PMID:28723028)
These phenotypes are associated with the disease rheumatoid arthritis (OMIM:180300).