A 3 year old child is carried into the emergency department because of pain in her left hip. Her mother stated that she woke up with the pain and has refused to walk all day because of the pain. The patient has been running a low grade fever and “just wasn’t acting right.”
The mother brought the child to the pediatrician earlier in the day. The pediatrician diagnosed the patient with “double ear infections” and prescribed the child that powerful pink healing elixir otherwise known as amoxicillin. When the mother asked the pediatrician why the child’s hip was hurting, the pediatrician stated that the child “probably slept on it wrong.” The mother stated that the pediatrician never even examined the child’s leg.
The child didn’t seem like she was getting better, so the mother brought her to the emergency department for another exam.
When I examined the leg, the child held her hip in flexion and cried with any movement of the hip joint. Distal sensory, motor, and circulatory exams were intact to the extent that the patient would allow an exam to be done. There was no appreciable swelling over the joints. She wouldn’t even try to walk. Oh, and her otoscopic exam was within normal limits.
I decided to do a few labs. Her WBC was 13,000 with 91% segs. The sedimentation rate was 120.
What’s the diagnosis, how is the diagnosis made, and what’s the treatment?
UPDATE MARCH 25, 2010
Final Diagnosis: Septic arthritis of the hip.
Culture showed staph aureus, which is the responsible organism in about half of all cases.
Nice summary of septic hip in pediatric patients is at Wheeless’ Online Orthopaedics
Kocher criteria include non-weight bearing on the affected side, sedimentation rate > 40, fever, and WBC count > 12,000. When all four criteria are present, septic arthritis has a 99% likelihood. When three criteria are present, the likelihood of septic arthritis is still 93%.
Diagnosis requires joint aspiration under either ultrasound or fluoroscopy.
Treatment requires surgical drainage and antibiotics. Preliminary treatment is usually a third generation cephalosporin – pending culture results. Keep in mind that MRSA is a growing problem (no pun intended) and that IV vancomycin may be necessary. Also keep in mind that sickle cell patients are prone to salmonella infections in bone and joints.
Unfortunately, septic arthritis may lead to many long-term hip problems such as dysplasia, deformities in hip development, and postinfectious arthritis – even with appropriate care.
As an aside, I was completely blown away by the number of thoughtful responses and differential diagnoses for this case. I intended it to be just a relatively straightforward case to jog the memories of the attendings and to teach the young grasshoppers. You guys came up with several things that even I hadn’t considered.
I’ll have to post these cases more often.
Thanks for the education!