Migratory arthritis in children - A clinical clue to diverse diagnoses

Migratory arthritis is classically associated with acute rheumatic fever (ARF), but may signify other medical conditions. We aimed to track the final diagnoses of this obscure presentation, and to distinguish clinical variables that differentiate ARF from other conditions in order to facilitate the clinical diagnosis of ARF. Medical records were reviewed of all the patients aged 0-18 years who presented with migratory arthritis during 2015-2023 at the emergency department, pediatric wards, and the rheumatology unit of a large tertiary medical center. Primary diagnoses, demographic, clinical, and laboratory parameters were extracted and compared between patients with ARF and those with other diagnoses. A total of 101 patients with migratory arthritis were identified. Of them, 50 (49.5%) were diagnosed with ARF. The others had various conditions, including reactive arthritis (9.9%), post-streptococcal reactive arthritis (7.9%), post-viral arthritis (5%), inflammatory bowel disease (4%), systemic lupus erythematosus (3%), and malignancy (2%). Factors associated with an ARF diagnosis compared to other diagnoses were: residence in areas of highly crowded households (P = 0.007), and elevated CRP (P = 0.002). Abnormal medical background, rash, and a positive antinuclear antibody test were associated with other diagnoses.

The differential diagnosis of pediatric migratory arthritis is diverse. Merely half of the patients were diagnosed with ARF. A considerable proportion of diagnoses related to post-infectious conditions. Malignancies, though rare, are an important differential. Only a small proportion had juvenile idiopathic arthritis. Migratory arthritis poses a diagnostic challenge and ARF should be differentiated from other diagnoses where applicable.

• Migratory arthritis is classically associated with acute rheumatic fever (ARF), but may signify other medical conditions. • The literature focusing on migratory arthritis is sparse.

• The differential diagnosis of pediatric migratory arthritis is diverse. • Merely half of patients were diagnosed with acute rheumatic fever.