In simple words: Reiter’s disease, also known as reactive arthritis, develops after an infection, usually in the genitals, urinary tract, or gut. It causes joint pain and stiffness, especially in the lower body. You might also have eye inflammation, problems peeing, skin rashes, and mouth sores.

Reiter's disease (reactive arthritis) is an inflammatory arthritis that develops in response to an infection, typically in the genitals, urinary tract, or intestines.It's characterized by joint pain and stiffness, particularly in the lower back, knees, ankles, and feet. Other symptoms can include eye inflammation, urinary problems, skin rashes, and mouth sores.

Example 1: A 25-year-old male presents with knee and ankle pain and stiffness following a recent chlamydia infection. He also experiences mild eye inflammation and painful urination. After examination and testing, he is diagnosed with Reiter's disease (M02.3)., A 35-year-old female experiences joint pain in her feet and lower back several weeks after a bout of food poisoning.She also develops a rash on her palms and soles. The diagnosis is Reiter's disease (M02.3)., A 40-year-old male with a history of recurrent urinary tract infections presents with heel pain, sausage-like swelling of his toes, and lower back pain that's worse at night. He tests positive for HLA-B27 and receives a diagnosis of Reiter's disease (M02.3).

Documentation should include the type, location, and laterality of affected joints, evidence of a preceding infection (e.g., STI, gastroenteritis), presence of other symptoms (eye inflammation, urethritis, skin lesions), and laboratory results (e.g., HLA-B27 testing).

** Although Reiter's syndrome is no longer the preferred term, it's still commonly used. The condition is associated with the HLA-B27 gene, and it can sometimes lead to long-term joint problems.