Poststreptococcal Reactive Arthritis: Diagnostic Challenges

Acute rheumatic fever and Post-streptococcal reactive arthritis

Acute rheumatic fever (ARF) and poststreptococcal reactive arthritis (PSRA) represent two distinct but related poststreptococcal conditions, both arising from an autoimmune response following Group A streptococcal (GAS) infection, typically pharyngitis. Although both illnesses have a shared trigger, their clinical presentations and long-term consequences differ markedly. ARF, a systemic inflammatory disorder, can impact several organs, particularly the heart, potentially resulting in chronic rheumatic heart disease with irreversible valve damage. The cornerstone of ARF treatment includes Streptococcus eradication therapy, symptom management, and secondary prophylaxis to prevent recurrence. In contrast, PSRA primarily presents as non-infectious, nonmigratory, persistent arthritis without carditis and generally resolves without lasting sequelae. Distinguishing PSRA from ARF is crucial for appropriate management and to avoid unnecessary long-term antibiotic prophylaxis. This review focuses on the key clinical features and diagnostic approaches for ARF and PSRA, along with an overview of their management strategies.

Approach to Musculoskeletal Pain in Children

Musculoskeletal (MSK) pain is a common pediatric problem and can occur due to many etiologies. A pediatrician should be clinically equipped to identify the cause of musculoskeletal pain by a meticulous history, a detailed physical examination and judicious use of appropriate investigations. In this review, the authors attempt to delineate the approach and discuss a few common causes of musculoskeletal pain.

Tonsillitis-Related Arthritis: Advanced Understandings of Tonsillitis and Sterile Inflammatory Arthritis

A 49-year-old man developed acute aseptic arthritis of the nonmigratory and asymmetrical type in his knee, ankle, and bilateral metatarsal joints 13 days after treatment with antibiotics for acute tonsillitis. He was diagnosed with tonsillitis-related arthritis after other rheumatic diseases were ruled out. Treatment with salazosulfapyridine, methotrexate, and methylprednisolone for 3 months did not completely improve. Then, tonsillectomy was undertaken and arthritis rapidly improved. Finegoldia magna (previously Peptostreptococcus magnus) was cultured from the microabscesses of the resected tonsils. After outpatient follow-up, the patient did not experience a relapse of arthritis for more than 2.7 years without any treatment. Poststreptococcal reactive arthritis (PSRA) is well described. However, up to 40% of patients with tonsillitis-related arthritis did not demonstrate evidence of streptococcal infection. It is noted that tonsillectomy is necessary to remove the tonsillar microabscesses and eradicate bacterial infection of the tonsils, especially for patients with a prolonged and/or recurrent course of PSRA and/or tonsillitis-related arthritis.

Expanding the spectrum of reactive arthritis (ReA): classic ReA and infection-related arthritis including poststreptococcal ReA, Poncet's disease, and iBCG-induced ReA

Reactive arthritis (ReA) is a form of sterile arthritis that occurs secondary to an extra-articular infection in genetically predisposed individuals. The extra-articular infection is typically an infection of the gastrointestinal tract or genitourinary tract. Infection-related arthritis is a sterile arthritis associated with streptococcal tonsillitis, extra-articular tuberculosis, or intravesical instillation of bacillus Calmette–Guérin (iBCG) therapy for bladder cancer. These infection-related arthritis diagnoses are often grouped with ReA based on the pathogenic mechanism. However, the unique characteristics of these entities may be masked by a group classification. Therefore, we reviewed the clinical characteristics of classic ReA, poststreptococcal ReA, Poncet’s disease, and iBCG-induced ReA. Considering the diversity in triggering microbes, infection sites, and frequency of HLA-B27, these are different disorders. However, the clinical symptoms and intracellular parasitism pathogenic mechanism among classic ReA and infection-related arthritis entities are similar. Therefore, poststreptococcal ReA, Poncet’s disease, and iBCG-induced ReA could be included in the expanding spectrum of ReA, especially based on the pathogenic mechanism.

Update on Post-Streptococcal Reactive Arthritis: Narrative Review of a Forgotten Disease

PURPOSE OF THE REVIEW

This topical review attempts to build the concepts of PSRA as an independent entity and discuss prevalent diagnostic criteria. It utilizes a search strategy to collate all clinical features of PSRA reported from across the world and also discusses laboratory and treatment options in brief.

RECENT FINDINGS

There are several immune-mediated diseases described after acute streptococcal infections. Post-streptococcal reactive arthritis (PSRA) is a sterile, self-limiting arthritis that occur as an immune sequelae to streptococcal infection. Though PSRA resembles the arthritis of acute rheumatic fever superficially, it is a separate entity in its own right. It is different from classical reactive arthritis too. It was being recognized worldwide and more frequently in the recent past, possibly due to heightened awareness amongst clinicians. However, research on this enigmatic immune phenomenon is limited. Most acceptable hypotheses suggest molecular mimicry sensitizing the immune system towards synovial peptides such as keratin, vimentin and laminin, leading to arthritis in a genetically predisposed individual. There is still much to be learnt from this unique disease about the vagaries of the immune system.