Pediatric Primary Care Case Studies (129 page)

Is the condition emergent?

The most important part of the diagnosis is to ensure that the hip pain is not caused by a bacterial infection of the hip joint. Early, accurate diagnosis of septic arthritis of the hip in children is critical because poor outcomes have been associated with a delay in diagnosis (Kocher, Mandiga, Zurkowski, Barnewold, & Kasser, 2004). Differentiating between septic arthritis and transient synovitis of the hip can be difficult.

Management

Tyler has a history of febrile illness in the past month and treatment with antibiotics for otitis media (OM) and upper respiratory infection (URI). The physical examination is positive for a painful left hip with pain on movement. Given the history and positive physical findings, an anteroposterior and lateral X-ray and laboratory tests including CBC with differential, ESR, and CRP would be indicated. The physiologic response to an early bacterial
infection can be variable and can result in serum makers (elevated ESR, WBC, and CRP) of inflammation within the normal range of values (Luhmann et al., 2004). If the laboratory values indicate septic arthritis, an ultrasound with hip aspiration would be indicated.

Medical management differs depending on the diagnosis. In transient synovitis, bed rest, non-weight-bearing activity, and nonsteroidal anti-inflammatory drugs are the standard treatment recommendations. In septic arthritis, the child would need to be managed by an orthopedic surgeon and requires immediate surgical intervention and intravenous antibiotics.

Test Results

After reviewing Tyler’s hip X-rays and laboratory values, you make the diagnosis of transient synovitis. The sedimentation rate is 6 mm/hr, C-reactive protein is 0.3 mg/L, and WBC count is 10,000/mm
³
.

Kocher and associates (2004) developed a clinical prediction algorithm for septic arthritis based on four clinical variables: history of fever, non-weight-bearing, an erythrocyte sedimentation rate of greater than or equal to 40 mm/hr, and serum white blood-cell count greater than 12,000/mm
³
. When all four variables are present the child has a 99.6% chance of having septic arthritis of the hip (Kocher et al., 2004). C-reactive protein level was added as an important part of the evaluation due to its elevation within 6 to 8 hours after onset of inflammatory process or infection. A C-reactive level of > 2.0 mg/dL is considered positive (Caird et al., 2006). Fever was defined as an oral temperature of 38.5°C (101.3°F) or greater during the week prior to admission (Luhmann et al., 2004).

Plain radiographs of the hip are useful in detecting other causes of hip pain; however, they are not sensitive enough to exclude the diagnosis of septic arthritis (Shah, 2005). An ultrasound of the hip is more sensitive than the plain film in identifying joint effusions of the hip. An ultrasound does not assist in determining the cause and is best used to guide hip aspiration. Diagnostic synovial fluid aspiration remains the gold standard for excluding septic arthritis of the hip (Shah). Specific etiologic agents can be identified through blood, bone, or joint aspirate cultures.

Educational plan: What does the mother need to know about transient synovitis and its management?

Transient synovitis is a benign disease, so treatment consists of supportive therapy. The major goal of therapy is to provide comfort and reduce activity until the inflammation subsides (Whitelaw & Schikler, 2008).

The treatment plan for Tyler will be:

   Bed rest or position of comfort for 7–10 days.

   Do not bear weight on affected limb.

   Avoid full unrestricted activity until limp and pain have resolved.

   In a 4-year-old, bed rest for any period of time may be difficult. Position the child on a couch or chair so he or she can observe family activity. Encourage sedentary activities with the help of siblings, such as board games, puzzles, or video games.

   Provide ibuprofen 10 mg/kg per dose given every 6 to 8 hours. The parent may administer it with food or milk to decrease GI upset.

   Return in 24 hours for repeat exam.

   Call if the child has high fever or symptoms worsen.

What medications will provide the best pain relief?