Juvenile idiopathic arthritis presenting as diffuse alveolar hemorrhage at onset: A case series

Objective: The etiology of diffuse alveolar hemorrhage (DAH) in childhood is often unknown, and it may be an early manifestation of rheumatic disease. Juvenile idiopathic arthritis (JIA) is one of the most common rheumatic diseases in children, but DAH as an onset manifestation of JIA is rare. This study summarizes the clinical characteristics of patients with JIA presenting as DAH.

Methods: We retrospectively analyzed the age of onset, clinical manifestations, imaging features, treatments, and prognosis of five cases of JIA presenting as DAH.

Results: Themedian age at DAH onset was 6 months (range, 2 months-3 years). Pallor was the most common manifestation of onset (5/5). Other symptoms included cough (2/5), tachypnea (2/5), hemoptysis (1/5), cyanosis (1/5), and fatigue (1/5). Imaging showed ground-glass opacity (GGO) (5/5), subpleural or intrapulmonary honeycombing (4/5), consolidation (3/5), interlobular septal thickening (2/5), and nodules (1/5). Anticitrullinated protein antibodies (ACPA) and rheumatoid factor (RF) were positive in five children (5/5), and antinuclear antibody (ANA) was positive in four children (4/5). ANA in three children and ACPA/RF in one child were positive before the onset of joint symptoms. The median age at the onset of joint symptoms was 3 years and 9 months (2 years and 6 months-8 years). Joint symptoms were mainly characterized by joint swelling, pain, and difficulty walking, and the most commonly affected joints were the knees, ankles, and wrists. After the diagnosis of DAH, the five patients were treated with glucocorticoids. Alveolar hemorrhage was effectively controlled in three cases, but the other two patients still had anemia and poor improvements in chest imaging. After joint symptoms, the patients were treated with glucocorticoids combined with diclofenac, disease-modifying antirheumatic drugs, and biological agents. Alveolar hemorrhage was in remission, and joint symptoms were relieved in the five cases.

Conclusion: DAH can be the first clinical manifestation of JIA, and joint involvement occurs 1-5 years later. Children with DAH who are positive for RF, ACPA, and/or ANA and have GGO accompanied by honeycombing on imaging should be concerned about their joint involvement in future.