Format

Send to

Choose Destination
Pediatr Rheumatol Online J. 2015 Feb 28;13:7. doi: 10.1186/s12969-015-0003-2. eCollection 2015.

Enthesitis as a component of dactylitis in psoriatic juvenile idiopathic arthritis: histology of an established clinical entity.

Author information

1
Division of Immunology, Boston Children's Hospital, Boston, MA USA.
2
Department of Pathology, Boston Children's Hospital, Boston, MA USA.
3
Department of Radiology, Boston Children's Hospital, Boston, MA USA.
4
Department of Orthopedic Surgery, Boston Children's Hospital, Boston, MA USA.
5
Division of Immunology, Boston Children's Hospital, Boston, MA USA ; Division of Rheumatology, Immunology, and Allergy, Brigham and Women's Hospital, Smith 516B, One Jimmy Fund Way, Boston, MA 02115 USA.

Abstract

CONTEXT:

Imaging of dactylitis in adult psoriatic arthritis suggests a pathophysiological role for enthesitis. However, histological definition of the dactylitic digit is unavailable.

OBJECTIVE:

We evaluated the role of enthesitis in dactylitis associated with psoriatic juvenile idiopathic arthritis (psJIA) in a child who underwent detailed imaging and histologic evaluation.

DESIGN:

Radiographs, ultrasound and high-resolution magnetic resonance imaging were employed to define the locus of disease in two dactylitic digits from a 14-year-old girl with psJIA. Biopsies were stained with hematoxylin and eosin, CD3, CD20, CD4, CD8 and CD117 and examined via light microscopy.

RESULTS:

Radiologic features of dactylitis included enhanced signal at digital entheses without accompanying synovitis or tenosynovitis. Histologically, finger and toe tissue exhibited hypervascular tenosynovium with a fibromyxoid expansion of fibrous tissue. This was accompanied by sparse to moderate perivascular lymphocytic inflammation consisting predominantly of T cells, with occasional admixed B cells and mast cells. Neutrophils and plasma cells were absent. Fibrocartilage exhibited reactive features including increased extracellular myxoid matrix, binucleation, and focal necrosis, without cellular inflammation. Fibrinous synovitis and mild reactive synoviocyte hyperplasia were seen.

CONCLUSIONS:

Dactylitis in psJIA bears a radiographic resemblance to the condition in adult psoriatic arthritis. Histologic hallmarks include an expanded mast cell-populated extracellular myxoid matrix, cartilage degeneration, and a T cell-rich perivascular inflammatory infiltrate. These findings help to define enthesitis as a clinicopathologic entity.

KEYWORDS:

Dactylitis; Enthesitis; Enthesitis related arthritis; Juvenile idiopathic arthritis; Psoriatic arthritis; Psoriatic juvenile idiopathic arthritis

PMID:
25774101
PMCID:
PMC4359473
DOI:
10.1186/s12969-015-0003-2
[Indexed for MEDLINE]
Free PMC Article

Supplemental Content

Full text links

Icon for BioMed Central Icon for PubMed Central
Loading ...
Support Center