Differential Diagnoses for Hand Edema in Elderly Females with Osteoarthritis

Primary Considerations

The American College of Rheumatology suggests that erosive hand osteoarthritis is a likely diagnosis given the patient's osteoarthritis history and non-pitting edema, which suggests bony rather than soft tissue swelling 1, 2
Erosive osteoarthritis typically has abrupt onset with marked pain, inflammatory symptoms including soft tissue swelling and erythema, and targets interphalangeal joints, with worse functional outcomes than non-erosive osteoarthritis 2
The European League Against Rheumatism recommends considering gout superimposed on pre-existing hand osteoarthritis, which complicates the clinical picture, primarily affecting metacarpophalangeal joints and wrists 1, 3
Psoriatic arthritis may target DIPJs or affect just one ray, with characteristic juxta-articular new bone formation on radiography, and the patient should be examined for psoriasis, nail dystrophy, or dactylitis 1, 2, 5
Rheumatoid arthritis mainly targets MCPJs, PIPJs, and wrists with symmetrical polyarthritis, but DIP joints can be involved, and the patient should be checked for strongly positive RF or anti-CCP antibodies and characteristic erosions on imaging 1, 5

Haemochromatosis mainly targets MCPJs and wrists, similar to gout, and should be considered in patients with a family history or other systemic features of iron overload 1, 3
Chronic non-bacterial osteitis would show bony swelling with bone marrow edema on MRI and typically affects sternoclavicular joints, spine, or mandible more commonly, with older age at onset and history of strain favoring osteoarthritis over CNO 5, 6

The patient should undergo a clinical examination to determine if swelling is truly bony or soft tissue, and to assess joint distribution, with DIPJs/PIPJs suggesting OA or erosive OA, and MCPJs/wrists suggesting RA, gout, or haemochromatosis 1, 2, 3
Plain radiographs of both hands are the gold standard, looking for joint space narrowing, osteophytes, subchondral sclerosis, and subchondral cysts, with subchondral erosion indicating erosive hand OA 1, 2
Laboratory testing, including CRP/ESR, serum urate, RF, and anti-CCP, can help support the diagnosis, but diagnosis requires a composite assessment of clinical features, joint distribution, and imaging 1, 2, 5