When you assess a patient with a swollen joint, limited range of motion, and/or pain, consider a diagnosis of juvenile idiopathic arthritis.
Start with a detailed history and physical examination. Questions to ask include: How long have the symptoms been present? Was the onset acute or gradual? What is its severity? Ask the patient to rate the severity of pain. Use a 0-10 rating scale in older children and a faces scale in younger kids. Remember that not all children with oligoarticular juvenile idiopathic arthritis (JIA) experience pain.
By Dr. Donald P. Goldsmith
Is there interference with school or any other activities? Are the symptoms improving or getting worse?
Also inquire about diurnal variation: Are symptoms more problematic in the morning or evening? Stiffness in the morning or following prolonged inactivity is a classic sign of arthritis in children as well as in adults. Also, what medications or other strategies has the patient tried, and how successful where they?
Inquire about associated symptoms. Fever, cutaneous eruption, weight loss, abdominal pain, diarrhea, and behavioral or visual changes are examples. Ocular inflammation is a common feature of some of the subtypes of juvenile arthritis.
Ask the patient or family about a history of trauma to rule out a fracture or significant intraarticular injury. Keep in mind that even chronic swelling of a joint sometimes may be an orthopedic issue.
One diagnosis you don’t want to miss is malignancy. You think automatically about arthritis when a child presents with joint pain, but all pediatric rheumatologists see a few children each year who turn out to have cancer instead. So be sure that pain truly is localized to the joint, and it’s not bone pain which may reflect the presence of leukemia, lymphoma, or another malignancy.
Remember arthritis is not always the primary disorder. During the initial evaluation you might see a child with inflammation of two of three joints. If you don’t ask about recurrent abdominal pain and/or low-grade fever, you may miss the fact that their arthritis is part of inflammatory bowel disease. If you have any questions about the primary vs. secondary nature of a child’s arthritis, refer the patient to a pediatric rheumatologist for further evaluation. The differential diagnosis for juvenile idiopathic arthritis (now the preferred name replacing "juvenile rheumatoid arthritis") can be lengthy.
Once a diagnosis of JIA is confirmed, a pediatric rheumatologist is best qualified to oversee ongoing care of the patient. Compared with 20 years ago, there are now a great many new agents specifically tailored to treat JIA (particularly biologics), and these medications require that those familiar with dosing schedules and side effects direct their administration. A medication that works well for one subtype of JIA may not work as well for another.
Physical and occupational therapists are critical for a successful approach to children with chronic arthritis. Their involvement helps to maintain range of motion, muscle strength, and endurance while preventing joint contractures and abnormalities of bone growth. The overall goal is to "mainstream" children back to their usual activities. However, if they participated in rugby, ice hockey, or tackle football, we will try to steer these patients to activities with a lower potential for direct trauma. We don’t want a child to be isolated from their peers.
It also is important not to overtest children with suspected arthritis. Laboratory testing is indicated if you strongly suspect an inflammatory process rather than for a child with vague aches and pains. Appropriate initial assays often include a complete blood count, urinalysis, sedimentation rate, and measurement of the C-reactive protein.
Tests such as an ANA (antinuclear antibody) and rheumatoid factor should be reserved for those children with symptoms and signs more likely to be associated with an inflammatory condition. These tests may be misleading with frequent false-positive results that cause undue anxiety for the patient and their family.
For more information on when to refer your patient, see the American College of Rheumatology’s 2010 Guidelines for the Referral of Children and Adolescents to Pediatric Rheumatologists.
Dr. Goldsmith is professor of pediatrics at Drexel University and chief of the rheumatology section at St. Christopher’s Hospital for Children, both in Philadelphia. Dr. Goldsmith said that he has no relevant financial disclosures.
This column, "Subspecialist Consult," appears regularly in Pediatric News, a publication of Elsevier.