### Date : 2024-05-29 11:14 ### Topic : Reactive Arthritis #medicine #infectology #rheumatology ---- ### What is Reactive Arthritis? Reactive arthritis, also known as Reiter’s syndrome, is a type of inflammatory arthritis that occurs as a reaction to an infection in another part of the body. It commonly affects the joints, eyes, and urinary tract. ### Causes Reactive arthritis is typically triggered by an infection, often in the gastrointestinal or genitourinary tract. The exact mechanism is not entirely understood, but it is believed that the body’s immune response to the infection mistakenly targets its own tissues. Common infections that can trigger reactive arthritis include: - **Chlamydia trachomatis** (a sexually transmitted infection) - **Salmonella**, **Shigella**, **Yersinia**, and **Campylobacter** (bacterial infections that cause gastrointestinal symptoms) ### Risk Factors - **Genetics**: The HLA-B27 gene is strongly associated with an increased risk of developing reactive arthritis. - **Age**: Most commonly affects adults between the ages of 20 and 40. - **Sex**: More common in men than in women, especially after a sexually transmitted infection. - **Recent infection**: Having a recent infection, particularly gastrointestinal or genitourinary, increases the risk. ### Symptoms Symptoms of reactive arthritis usually develop 1 to 4 weeks after the initial infection and can vary in severity. They often include: #### Musculoskeletal Symptoms - **Joint pain and swelling**: Typically affects the knees, ankles, and feet. - **Enthesitis**: Inflammation where tendons and ligaments attach to bone, often seen in the heel. - **Dactylitis**: Swelling of an entire finger or toe, sometimes referred to as "sausage digit". #### Genitourinary Symptoms - **Urethritis**: Inflammation of the urethra, causing pain during urination and discharge. - **Cervicitis**: Inflammation of the cervix in women, leading to pelvic pain and discharge. #### Ocular Symptoms - **Conjunctivitis**: Inflammation of the conjunctiva, leading to redness and irritation of the eyes. - **Uveitis**: Inflammation of the uvea, causing eye pain, redness, and blurred vision. #### Other Symptoms - **Skin rashes**: Such as keratoderma blennorrhagicum (painless, scaly sores on the palms and soles) and circinate balanitis (sores on the glans penis). - **Mouth ulcers**: Painless ulcers in the mouth. ### Diagnosis Diagnosis of reactive arthritis is primarily clinical, based on symptoms and medical history, particularly a recent infection. Tests may include: - **Blood tests**: To detect markers of inflammation (e.g., ESR, CRP) and genetic markers (HLA-B27). - **Urine tests**: To check for evidence of infection. - **Joint fluid analysis**: To rule out other types of arthritis. - **Imaging**: X-rays or MRI to look for joint damage. ### Treatment There is no cure for reactive arthritis, but treatment focuses on managing symptoms and addressing the underlying infection. #### Medications - **Antibiotics**: To treat the initial infection if it is still present. - **Nonsteroidal anti-inflammatory drugs (NSAIDs)**: To reduce pain and inflammation. - **Corticosteroids**: For severe inflammation, either orally or as injections into affected joints. - **Disease-modifying antirheumatic drugs (DMARDs)**: Such as sulfasalazine or methotrexate, for persistent or severe cases. - **Biologics**: Tumor necrosis factor (TNF) inhibitors for refractory cases. #### Physical Therapy - **Exercise**: To maintain joint function and flexibility. - **Physical therapy**: To improve muscle strength and reduce pain. ### Prognosis The prognosis for reactive arthritis varies: - **Short-term**: Many people experience a significant improvement in symptoms within a few months. - **Long-term**: Some may have recurrent episodes or develop chronic arthritis, especially if HLA-B27 positive. With appropriate treatment, most people can manage their symptoms effectively and maintain a good quality of life. ### Prevention Preventing infections that can trigger reactive arthritis is key: - **Safe sex practices**: To reduce the risk of sexually transmitted infections. - **Proper food handling and hygiene**: To prevent gastrointestinal infections. In summary, reactive arthritis is an autoimmune condition triggered by an infection, leading to joint inflammation and other systemic symptoms. Diagnosis involves clinical evaluation and sometimes laboratory tests. Treatment focuses on managing symptoms and addressing the underlying infection.