Juvenile Idiopathic Arthritis: A Review of Novel Diagnostic and Monitoring Technologies

Asymptomatic intraspinal epidermoid cyst in a 7-year-old male with juvenile idiopathic arthritis identified by an advanced physiotherapist practitioner: a case report

BACKGROUND

Pediatric intraspinal epidermoid cysts are rare with potential to cause life-altering outcomes if not addressed. Reports to date describe symptomatic presentations including loss of bladder or bowel function and motor and sensory losses. This case report identifies the diagnostic challenge of an asymptomatic intraspinal epidermoid cyst in the cauda equina region presenting in a 7-year-old male with juvenile idiopathic arthritis (JIA).

DIAGNOSIS

An advanced physiotherapist practitioner assessed and diagnosed a previously healthy 7-year-old-male of South Asian descent with JIA based on persistent knee joint effusions. Complicating factors delayed the investigation of abnormal functional movement patterns, spinal and hip rigidity and severe restriction of straight leg raise, all atypical for JIA. Further delaying the diagnosis was the lack of subjective complaints including no pain, no reported functional deficits, and no neurologic symptoms. A spinal MRI investigation 10-months from initial appointment identified intraspinal epidermoid cysts occupying the cauda equina region requiring urgent referral to neurosurgery.

DISCUSSION

Clinical characteristics and pattern recognition are essential for diagnosing spinal conditions in pediatric populations. Diagnostic challenges present in this case included co-morbidity (JIA), a severe adverse reaction to treatment, a lack of subjective complaints and a very low prevalence of intraspinal epidermoid cysts.

IMPACT STATEMENTS

Early signs of pediatric asymptomatic intraspinal epidermoid cysts included abnormal functional movement patterns, rigidity of spine, severely limited straight leg raise and hip flexion without pain. Advanced physiotherapist practitioners can be integral to pediatric rheumatology teams considering their basic knowledge in musculoskeletal examination and functional mobility assessment when identifying rare spinal conditions that present within the complex context of rheumatic diseases.

Juvenile Idiopathic Arthritis With Associated Inflammatory Bowel Disease and CARD8 Mutation

Juvenile idiopathic arthritis is a common chronic childhood disease, with a prevalence of ∼1 per 1000 children. Arthritis can also be a manifestation of other inflammatory conditions, such as inflammatory bowel disease (IBD). Studies suggest a genetic influence in IBD, including mutations in CARD8. CARD8 is a negative regulator of the NLRP3 inflammasome, and mutations in this gene are hypothesized to induce gastrointestinal inflammation. However, few studies have evaluated this association and most have included a limited number of patients. We present a case of a pediatric patient with IBD-associated arthritis and a CARD8 mutation. Our patient is a 7-year-old female who was initially evaluated by rheumatology for right leg pain and an intermittent rash. She had clinically active arthritis on exam and was started on methotrexate with only slight improvement. Additional workup revealed sacroiliitis by imaging, elevated inflammatory markers, no anemia, and a variant of unknown significance in CARD8. Adalimumab was recommended but before medication initiation, our patient's symptoms progressed to worsening joint pain, fatigue, fevers, nausea, vomiting, diarrhea, and hematochezia. Infectious testing was negative. Fecal calprotectin was >8000 µg/g. A colonoscopy revealed IBD most consistent with Crohn's disease. Adalimumab was ultimately added, and she has responded well to combination therapy. This case report highlights the association between CARD8 mutations and IBD, especially in the setting of IBD-associated arthritis.

MicroRNA-27a-3p enhances the inflammatory phenotype of Juvenile Idiopathic Arthritis fibroblast-like synoviocytes

BACKGROUND

Juvenile Idiopathic Arthritis (JIA) is the most prevalent chronic pediatric rheumatic disorder. In joints of JIA patients, aggressive phenotypic changes in fibroblast-like synoviocytes (FLS) of the synovial lining play a key role in inflammation. MicroRNAs are dysregulated in rheumatoid arthritis and JIA, including miR-27a-3p. However, it is not understood if miR-27a-3p, enriched in JIA synovial fluid (SF) and leukocytes, alters FLS function.

METHODS

Primary JIA FLS cells were transfected with a miR-27a-3p mimic or a negative control microRNA (miR-NC) and stimulated with pooled JIA SF or inflammatory cytokines. Viability and apoptosis were analyzed by flow cytometry. Proliferation was evaluated using a ³H-thymidine incorporation assay. Cytokine production was assessed by qPCR and ELISA. Expression of TGF-β pathway genes was determined using a qPCR array.

RESULTS

MiR-27a-3p was constitutively expressed in FLS. Overexpression of miR-27a-3p caused increased interleukin-8 secretion in resting FLS, and interleukin-6 was elevated in SF-activated FLS compared to miR-NC. Furthermore, stimulation with pro-inflammatory cytokines augmented FLS proliferation in miR-27a-3p-transfected FLS relative to miR-NC. Expression of multiple TGF-β pathway genes was modulated by overexpression of miR-27a-3p.

CONCLUSIONS

MiR-27a-3p significantly contributes to FLS proliferation and cytokine production, making it a potential candidate for epigenetic therapy that targets FLS in arthritis.

Proliferative flexor tenosynovitis in the index finger of a 10-year-old baseball player gloved hand: A case report

Flexor tenosynovitis is rare in young children. This case report describes that of a 10-year-old boy with diffuse swelling of the left index finger, pain when catching a ball, and progressive inability for full flexing of the finger 2 months after starting baseball play. Magnetic resonance imaging showed a defined lesion with iso-signal intensity to muscle on T1-weighted imaging, and with high signal intensity to muscle on T2-weighted imaging. It was enhanced in T1-weighted fat suppression imaging with gadolinium enhancement. Surgical excision relieved the symptom. Histopathological findings mainly indicated proliferation of synoviocytes and plasma cell and lymphocyte infiltration. We speculated that the physical impact of the ball on the left index finger of his gloved hand during catching activated some immunological mechanism and thereby caused nonspecific tenosynovitis in this young baseball player. Awareness of this pathophysiology might raise confidence in proper diagnosis for assessing the swelling of fingers in young baseball players.