Introduction
Reactive arthritis (ReA) is a type of joint inflammation that happens after an infection, usually in the urinary or digestive systems. It is part of a group of conditions called spondyloarthropathy (SpA), which have similar clinical features. Typically, ReA shows up with joint pain in the lower limbs, and patients may also experience inflammation in the sacroiliac joints, tendons, and fingers. Other symptoms may include eye inflammation, urethritis, and skin issues like pustules on the feet. Although ReA was initially thought to be a sterile arthritis, finding active Chlamydia bacteria in the joint fluid of some patients has raised questions about its causes. It is caused by many things, such as genetics. Several studies and updates are going on reactive arthritis. This article explains the update on reactive arthritis.
What Is Reactive Arthritis?
Reactive arthritis (ReA) encompasses a range of joint, tendon, skin, and eye symptoms that emerge following infections in the genital, urinary, digestive, or respiratory systems. Typically, it manifests as joint inflammation, especially after infections in the genital or gastrointestinal tracts. In the United States, the occurrence of reactive arthritis ranges from 3.5 to 5 cases per 100,000 people. Various factors are involved in arthritis. These factors include diverse diagnostic approaches, varying clinical presentations, a lack of specific laboratory markers, geographical factors leading to exposure to multiple pathogens, distinct genetic backgrounds, different infection severities, and recent changes in the microbiome. Reactive arthritis commonly affects a younger population, usually between 18 and 40 years old, with a peak between 20 and 29 years. The condition is more prevalent in white individuals, as the presence of the HLA-B27 gene is higher in this group compared to other ethnicities. The global prevalence of ReA in adults is estimated at 1 in 1000, though this varies based on geographical location. This is a rare disease.
What Causes Reactive Arthritis?
The most common infections associated with reactive arthritis are the following:
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Mycobacterial Infection - Poncet's disease is a form of non-erosive inflammatory arthritis that develops after a mycobacterial infection. In contrast to tuberculous arthritis, the joint affected by Poncet's disease does not show the presence of mycobacteria. This condition commonly arises after pulmonary tuberculosis, although it can also be associated with tuberculosis infection outside the lungs. Additionally, reactive arthritis has been observed following intravesical BCG therapy for bladder cancer. It is crucial to recognize that Poncet's disease and post intravesical BCG reactive arthritis are distinct entities separate from the typical form of reactive arthritis.
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Streptococcal Infection - Poststreptococcal reactive arthritis (PSRA) is regarded as a distinct condition from typical reactive arthritis, often categorized as an infection-related arthritis. Despite both conditions involving arthritis arising from an infection outside the joints, they exhibit distinct clinical features. In contrast to classical reactive arthritis, which typically manifests as oligoarthritis, PSRA tends to induce polyarthritis. Additionally, HLA-B27 is found in fewer than 10 percent of PSRA cases.
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Human Immuno Virus - Reactive arthritis has been associated with HIV. Individuals may experience joint inflammation in the lower limbs, along with enthesitis and skin issues. Given that HIV can be transmitted through sexual contact, it is crucial to rule out hidden Chlamydia infection. In instances of intravenous drug use, it is important to exclude conditions like septic arthritis and bacterial endocarditis.
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COVID -19 - Since the onset of the COVID-19 pandemic in 2019, ongoing research has revealed additional details about its rheumatic effects. Like many other viral infections, COVID-19 has the potential to induce joint and muscle pain in affected individuals.
What Are Clinical Features Of Reactive Arthritis?
The clinical signs of reactive arthritis encompass manifestations in the joints and surrounding areas, as well as mucocutaneous, genitourinary, and ocular features.
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Joint Involvement- In terms of joint involvement, reactive arthritis commonly induces an acute, asymmetrical oligoarthritis affecting the larger joints in the lower limbs, with occasional polyarthritis in the upper limbs. Axial engagement may manifest in the cervical, thoracic, and lumbosacral spine, and sacroiliitis is recognizable by lower back pain exacerbated at night, along with alternating buttock pain. Enthesitis, marked by inflammation at tendon and ligament insertion points into bone, causes localized pain, swelling, and tenderness, particularly in areas like the Achilles tendon and plantar aponeurosis insertions into the calcaneus, resulting in discomfort during walking.
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Dactylitis - Dactylitis, or sausage digit, involves diffuse swelling of an entire toe or finger and is attributed to digital tendonitis, interphalangeal joint synovitis, and multiple entheseal lesions. This condition is prevalent in spondyloarthropathies and may occur in up to 40 percent of certain populations with reactive arthritis.
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Mucocutaneous Involvement - Mucocutaneous features are observed in up to half of patients, with keratoderma blennorhagicum being highly indicative of reactive arthritis. These pustular lesions, primarily found on plantar areas, may transform into scaly, hyperkeratotic patches that merge into psoriatic plaques. Circinate balanitis, characterized by painless, superficial psoriasiform lesions on the glans or shaft of the penis, and oral ulceration are also noteworthy. Nail abnormalities, resembling psoriatic onychodystrophy, such as dystrophy and thickening, can occur.
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Genitourinary Symptoms- It may result from the underlying infection, such as Chlamydia, but can also serve as an extra-articular manifestation of reactive arthritis, including postenteric ReA. Symptoms encompass urethritis, cervicitis, salpingo-oophoritis, cystitis, and prostatitis.
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Ocular Symptoms - Ocular manifestations consist of conjunctivitis, keratitis, episcleritis, and anterior uveitis. Conjunctivitis and acute anterior uveitis are observed in approximately 50 percent and 75 percent of men with urogenital and enteric reactive arthritis, respectively. These ocular conditions typically manifest early in the disease and can precede arthritis onset by a few days.
What Are Treatments Of Reactive Arthritis?
The following are the treatment of reactive arthritis:
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Antibiotics - Antibiotics do not play a role in treating the arthritis itself; however, they may be necessary for addressing the underlying infection that triggered the condition. Typically, patients with acute diarrheal illness do not require antibiotic therapy unless they are systemically unwell, immunocompromised, or have significant comorbidities. The course of post dysenteric reactive arthritis is unlikely to be influenced by antibiotic treatment. When Chlamydia trachomatis is identified, antibiotic therapy is recommended for both the patient and their partner. While some studies suggest a shorter duration of reactive arthritis with prolonged antibiotic therapy, this approach is not standardized.
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Initial Therapy - Regarding the initial therapy, most cases of reactive arthritis resolve on their own. Symptomatic relief is the primary goal of treatment, with NSAIDs usually being the first-line option.
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NSAIDS - NSAIDs may be contraindicated in patients with renal, cardiac, or gastrointestinal issues, and potential side effects should be discussed with patients. If NSAIDs are ineffective or contraindicated, intra-articular glucocorticoid injections may be beneficial. In cases where multiple joints are involved, systemic glucocorticoids can be considered. The choice of dosage and tapering regimen depends on the number of joints affected and the severity of inflammation, with the goal of tapering to the lowest effective dose. Due to the significant adverse effects associated with long-term steroid use, consideration should be given to providing stomach and bone-protection therapy.
Conclusion
Reactive arthritis is a rare inflammatory disease. It affects the eyes, joints, and skin. There are differential diagnoses should be considered, such as other spondyloarthropathies, septic arthritis, crystal arthritis, disseminated gonococcal infection, acute rheumatic fever, inflammatory bowel disease, Behçet’s disease, coeliac disease, Whipple’s disease, parasitic infections, and viral infections. These conditions may present similarly to reactive arthritis, and their diagnosis may require various tests and investigations. But after prompt diagnosis reactive arthritis is confirmed. The treatment of reactive arthritis depends upon the patient.
