Also, I think there’s a typo -> polyarticular is 5 or MORE joints, not LESS.

I’ve rephrased to make it more clear. Also, changed the typo from LESS to MORE. Revised version is below.

JUVENILE RHEUMATOID ARTHRITIS (JRA)

KNOW JUVENILE RHEUMATOID ARTHRITIS WELL! The diagnosis requires knowing quite a few details. The child should have been under the age of 16 at the time of symptom onset. Symptoms must be present for at least 6 WEEKS before the diagnosis can be made. In children, if arthritis is present it is more common in the LARGE joints and rheumatoid nodules are much less common when compared to adults. A positive rheumatoid factor indicates a worse prognosis. Do NOT order a rheumatoid factor for diagnostic purposes. It can help with prognosis/subtyping, but a negative RF does NOT rule out RA.

* OLIGOARTICULAR JRA (OLIGOARTHRITIS): This refers to JRA that affects 4 OR LESS JOINTS, and is the more common type of JRA (>50%). Positive markers (rheumatoid factor and ANA) make this subtype much more likely. It’s more common in younger girls and is associated with chronic uveitis. Since visual complaints may be absent, patients need to have regular eye exams. Boys have a better prognosis.

• MNEMONIC: The O’s for OligO look like EYES and need regular eye exams because it is the more serious subtype.

* POLYARTICUlAR JRA (POLYARTHRITIS): This refers to JRA that affects 5 OR MORE JOINTS. Also more common in young girls. Systemic symptoms outside of the joints is not common.

* SYSTEMIC (aka STILLS DISEASE): This is equally as common in boys and girls. There are many classic symptoms and finding to be aware of including an episodic, salmon-colored “EVANESCENT RASH.” Patients may also have an extremely high LEUKOCYTOSIS (> 30K), with spiking fevers, lymphadenopathy and possible hepatosplenomegaly. Patients may also have pleurisy, pericarditis and the Koebner phenomenon (linear skin lesions appearing along a site of injury, rubbing or scratching). Serum markers are NEGATIVE.

• PEARL: If everything else fits and the patient doesn’t have an arthritis, go ahead and pick this diagnosis! The other symptoms are commonly present well before the arthritis component kicks in.
• PEARL: This can be a difficult diagnosis to make and is often missed in clinical practice and on the pediatric board exam. Please be VERY, VERY comfortable with this topic.
• PEARLS:  In comparison to leukemia, pain is in the AM (not at night), pain is in the joints (not the bone), mild hematologic anomalies (not severe), symptoms wax and wane (not persistent/worsening), symptoms are insidious in onset (not acute) and JRA may have a rash. BOTH can have lymphadenopathy and hepatosplenomegaly. In comparison to septic arthritis, remember the insidious onset of symptoms for JRA (not acute).

* TREATMENT: First line treatment = NSAIDS. Second line treatment = STEROIDS.