2. • Juvenile idiopathic arthritis (JIA) is characterized by chronic arthritis in one or more
joints for at least 6 weeks.
• The exact cause of JIA is not known, but there is substantial evidence that it is an
autoimmune process with genetic susceptibility factors
Oligoarticular Polyathicular
Systemic
Enthesitis-
associated
5. 1
Involved joints are often
swollen, warm to touch,
and painful on movement
or palpation with reduced
range of motion but
usually are not
erythematous.
2
Morning stiffness with a
limp or gelling after
inactivity.
3
Easy fatigability and poor
sleep quality may be
associated.
4
Arthritis in large joints,
especially knees, initially
accelerates linear growth,
causing the affected limb
to be longer and resulting
in a discrepancy in limb
lengths.
5
Continued inflammation
stimulates rapid and
premature closure of the
growth plate, resulting in
shortened bones.
7. • hand/wrist involvement most
common.
• deformity is wrist ulnar
deviation and flexion with
MCP stiffness in extended,
swollen & radially deviated
digits position
• 60% remission rate
8. Polyarticular Type
affects 25%
of patients
01
> 5 joints
involved
02
small joint
involvement
(hand, wrist)
03
symmetric
findings
04
F>M
05
9. • most common type
• early-onset associated with iridiocyclitis in 50% and chronic
uveitis.
• obtain opthalmology consult; requires frequent
ophthalmologic exams (q4mth if ANA+; q6mth if ANA-)
• girls are affected four times more often than boys in early-
onset
• peak age 2-3 yrs
• late-onset seen more frequent in boys
• typical finding is a limp that improves during day
• best prognosis for long term remission (70%)
10. Systemic Type
comprises 5%–10%
of patients
01
systemic symptoms
(rash, fever, multiple
joint involvement)
02
anemia, high WBC,
elevated ESR, CRP,
platelets
03
hepatosplenomegaly,
lymphadenopathy,
pericarditis
04
M=F, age 5-10y
05
11. • includes Stills disease
• poorest prognosis
• Around 90% patients have a
characteristic evanescent, salmon-
pink macular rash that is most
prominent on pressure areas and
when fever is present
12. Enthesitis-associated Type
comprises
approximately 10%–
20% of patients
01
M > F
02
typically
associated with
lower extremity,
large joint arthritis
03
inflammation of
tendinous insertions
(enthesopathy), such
as the tibial tubercle
or the heel
04
Low back pain and
sacroiliitis
05
13.
14. There are two additional subtypes of JIA
• Children with psoriatic arthritis may have typical psoriasis, but may
also present prior to the onset of the classic thick scaly plaques and have
more subtle changes such as nail pitting . Patients with psoriatic arthritis may
also present with dactylitis or “sausage digit,” which is painful swelling of an
entire finger or toe.
• Undifferentiated JIA, comprising 10% of patients, includes children with
chronic arthritis that do not meet criteria for any of the other subgroups or
meet more than one criterion
16. • Elevated WBC and platelet counts and a microcytic
anemia (anemia of chronic disease). Low WBC count, low
platelet count >> suspect MAS (Macrophage Activation
Syndrome)
• Eevated ESR and C-reactive protein (CRP)
• Elevated ANA titers are present in 40-85% of children
with oligoarticular or polyarticular JIA but are rare with
SoJIA. It is associated with increased risk of chronic
uveitis in JIA.
• 5-10% of patients with polyarticular JIA are seropositive
for RF.
• Anti–cyclic citrullinated peptide (CCP) antibody, like RF,
is a marker of more aggressive disease.
• HLA-B27 is positive in enthesitis related form
19. MRI is more sensitive
than radiography to
early changes most
sensitive radiologic
indicator of disease
activity. It can depict
synovial
hypertrophy, define
soft tissue swelling,
and demonstrate
excellent detail of the
status of articular
cartilage and overall
joint integrity
Early radiographic changes of arthritis include:
• Soft tissue swelling
• Periarticular osteoporosis
• Periosteal new-bone apposition around
affected joints
Continued active disease may lead to
• Subchondral erosions
• Loss of cartilage
• Varying degrees of bony destruction
• Fusion
22. Primary goals of medical therapy are:
• To eliminate active disease
• To normalize joint function
• To preserve normal growth
• To prevent long-term joint damage
Children with JIA need individualized treatment plans, and management is tailored according
to
• Disease subtype
• Severity
• Presence of poor prognostic indicators
• Response to medications.