Emergent high fatality lung disease in systemic juvenile arthritis

Ann Rheum Dis. 2019 Dec;78(12):1722-1731. doi: 10.1136/annrheumdis-2019-216040. Epub 2019 Sep 27.

Abstract

Objective: To investigate the characteristics and risk factors of a novel parenchymal lung disease (LD), increasingly detected in systemic juvenile idiopathic arthritis (sJIA).

Methods: In a multicentre retrospective study, 61 cases were investigated using physician-reported clinical information and centralised analyses of radiological, pathological and genetic data.

Results: LD was associated with distinctive features, including acute erythematous clubbing and a high frequency of anaphylactic reactions to the interleukin (IL)-6 inhibitor, tocilizumab. Serum ferritin elevation and/or significant lymphopaenia preceded LD detection. The most prevalent chest CT pattern was septal thickening, involving the periphery of multiple lobes ± ground-glass opacities. The predominant pathology (23 of 36) was pulmonary alveolar proteinosis and/or endogenous lipoid pneumonia (PAP/ELP), with atypical features including regional involvement and concomitant vascular changes. Apparent severe delayed drug hypersensitivity occurred in some cases. The 5-year survival was 42%. Whole exome sequencing (20 of 61) did not identify a novel monogenic defect or likely causal PAP-related or macrophage activation syndrome (MAS)-related mutations. Trisomy 21 and young sJIA onset increased LD risk. Exposure to IL-1 and IL-6 inhibitors (46 of 61) was associated with multiple LD features. By several indicators, severity of sJIA was comparable in drug-exposed subjects and published sJIA cohorts. MAS at sJIA onset was increased in the drug-exposed, but was not associated with LD features.

Conclusions: A rare, life-threatening lung disease in sJIA is defined by a constellation of unusual clinical characteristics. The pathology, a PAP/ELP variant, suggests macrophage dysfunction. Inhibitor exposure may promote LD, independent of sJIA severity, in a small subset of treated patients. Treatment/prevention strategies are needed.

Keywords: DMARDs (biologic); adult onset still's disease; inflammation; juvenile idiopathic arthritis; treatment.

Publication types

  • Multicenter Study
  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Arthritis, Juvenile / complications*
  • Biopsy
  • Child
  • Child, Preschool
  • Female
  • Follow-Up Studies
  • Humans
  • Incidence
  • Infant
  • Lung / diagnostic imaging*
  • Lung Diseases / diagnosis
  • Lung Diseases / epidemiology*
  • Lung Diseases / etiology
  • Male
  • Prognosis
  • Retrospective Studies
  • Survival Rate / trends
  • Tomography, X-Ray Computed
  • United States / epidemiology

Supplementary concepts

  • Rheumatoid Arthritis, Systemic Juvenile