What is the most likely diagnosis for a patient with joint pain, urinary pain, and conjunctivitis?

The clinical presentation of joint pain, urinary pain, and conjunctivitis is highly suggestive of reactive arthritis. Reactive arthritis is a type of inflammatory arthritis that occurs in response to an infection in another part of the body, typically involving the urogenital or gastrointestinal tract. The classic triad of symptoms associated with this condition includes arthritis, urethritis (which would explain the urinary pain), and conjunctivitis.

Reactive arthritis often develops after a patient has experienced a genitourinary infection; common pathogens associated with this condition include Chlamydia trachomatis, which can lead to urethritis, and other infections such as Salmonella or Shigella, which can cause gastrointestinal symptoms. The conjunctivitis seen in reactive arthritis is often acute and self-limiting.

Rheumatoid arthritis, while a well-known inflammatory condition, does not typically present with urinary symptoms or conjunctivitis. Septic arthritis would more likely present with acute joint inflammation due to a bacterial infection directly within the joint without the additional systemic features of conjunctivitis and urinary symptoms. Systemic lupus erythematosus is a systemic autoimmune disease and would have a different set of signs and symptoms, typically involving multi-system involvement and different patterns of joint involvement.

Thus, the combination of