A 70-year-old male with a history of gout and chronic kidney disease presents with bilateral knee pain and swelling. He has recently started on diuretics for hypertension. What are the potential diagnoses, and what are the next steps?
The bilateral knee pain and swelling in a patient with a history of gout could be due to a gout flare, particularly given the recent start of diuretics, which can precipitate gout attacks. Other possibilities include osteoarthritis, rheumatoid arthritis, or pseudogout. The next steps should include blood tests for uric acid and inflammatory markers, and potentially joint aspiration to confirm the presence of urate crystals and rule out other types of arthritis.