Doctors classify JRA according to the number of joints involved and the presence or absence of certain antibodies in the blood. These antibodies are special proteins made by the immune system.

Pauciarticular JRA involves four or fewer joints and is the most common Juvenile Rheumatoid Arthritis, affecting almost half of all JRA cases.

The most worrisome effect of  Pauciarticular is the damage it can do to the eyesight. 20-30% of children develop some problems with their eyes.

It will affect girls earlier than boys, but boys may have longer lasting problems with arthritis than girls.
Pauciarticular (paw-see-are-tick-you-lar) JRA 

Usually it is the large joints of the knees, ankles or elbows that are involved.

When eye disease is present, up to 80% test positive for antinuclear antibodies (ANA). 

The good news is most children with pauciarticular JRA outgrow arthritis during adolescence. 

However, some continue to have problems with their eyes or recurring symptoms of joint pain. 

There Are Two Different Types of Pauciarticular JRA:
First Type:  
·    Common of girls under the age of 7.
·    1/3 of children develop chronic iridocyclitis or uveitis, inflammation of eye.
Second Type:
·    Typically develops after age 8 and in boys.
·    Symptoms show up most often in the lower spine (sacroiliac joints), hips, knees, ankles and tendons.
·    These children may also develop eye problems, but this is usually acute rather than chronic uveitis, with redness and eye pain.
·    This type of pauciarticular JRA may be the first sign of another arthritis-related condition, such as one of the spondyloarthropathies which affect areas around the joint where your ligaments and tendons attach to bone. Spondyloarthropathies are a family of long-term, chronic diseases of joints.
This group of diseases is associated with a genetic factor, HLA-B27 in some people.

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