Other than fever and refusal to bear weight, the child had no other symptoms and was progressing on ibuprofen and antibiotics.
The patient
A 14-month-old female presented to the emergency department with fever and refusal to bear weight. She had bilateral ear tube insertion 13 days previously and presented to her primary care provider (PCP) three days prior for a viral respiratory infection.
She presented to her PCP the day before her admission for refusal to bear weight. Bilateral ultrasounds were ordered of the hips and knees and were normal. She was treated with scheduled ibuprofen and close follow-up.
As she continued to refuse to bear weight and developed a fever, the parents were instructed to take her to the emergency department.
She was febrile in the emergency department, and radiographs of lower extremities were normal.
Labs showed elevated white blood cell counts of 20K, ESR 59, CRP 3.2.
She was admitted, started on intravenous antibiotics and placed on the MRI schedule for the next morning. Before the MRI, the parents stated that the limp appeared to resolve with ibuprofen for the most part and that the patient was acting and playing normally.
An MRI of the pelvis and lumbar spine with and without contrast was performed. The patient was sedated for the MRI. After both MRIs were read as normal, it was noted that the patient had fluid in the left knee. A second ultrasound of the left knee was then obtained which showed an increase in fluid (progression from the previous day) and concern for septic arthritis. The patient then was taken to the operating room urgently for an irrigation and debridement.
Cell count came back at 143,000. A diagnosis of septic arthritis is considered positive with a cell count over 50,000. Intraoperative cultures obtained at the time of surgery came back negative.
The challenge
Initially the patient presented to the PCP without fever and refusal to bear weight. Bilateral ultrasounds were normal.
Over the next 24 hours the patient developed a fever and was admitted. In the emergency department, the knee ultrasound was normal. The next morning the pelvis MRI was normal as well. The patient also was improving with ibuprofen and antibiotics but still had elevated markers. After the MRI, the patient was reevaluated and was noted to have fluid in the knee which had progressed from the previous day’s ultrasound.
Normal left knee
Abnormal left knee
A repeat ultrasound was performed. It showed an increase in fluid and concern for arthritis. The patient then was taken to the operating room urgently for irrigation and debridement.
Septic arthritis is more common in immunocompromised patients or patients who have had recent procedures. This patient had ear tubes placed less than two weeks prior and more recently had an upper respiratory infection. Both of those events most likely led to an immunocompromised state, which allowed any bacteria in the patient’s blood to travel to the knee and develop septic arthritis.
If we had not had high concern for septic arthritis, the patient may have been discharged, as she was progressing well on antibiotics and anti-inflammatories. Without surgery, septic arthritis can be catastrophic to a patient.
The providers
Kent L. Walker, D.O.
Pediatric Orthopedic Surgeon
Norton Children’s Orthopedics of Louisville
Affiliated with the UofL School of Medicine
Julianne V. Green, M.D., Ph.D.
Norton Children’s Infectious Diseases
Affiliated with the UofL School of Medicine
Wilson E. Reinke, M.D.
Pediatric Hospitalist
Norton Children’s Inpatient Care
Affiliated with the UofL School of Medicine
Pediatric Emergency Medicine Physician
Norton Children’s Emergency Medicine
Affiliated with the UofL School of Medicine
Brittany K. Albers, M.D.
Pediatric Radiologist
Norton Children’s Radiology
Affiliated with the UofL School of Medicine
The solution
The patient urgently was taken to the operating room for irrigation and debridement. The patient was continued on IV antibiotics and transitioned to oral antibiotics at discharge.
The intraoperative cultures came back negative, so the patient was treated for presumed kingella. This bacteria does not present with severe signs and symptoms as with streptococcus, staphylococcus and other bacteria.
The result
The universal bacterial PCR eventually came back positive for kingella. The patient is recovering well and will continue follow-up for least one year.
Refer a patient
To refer a patient to Norton Children’s Orthopedics of Louisville, visit Norton EpicLink and choose EpicLink referral to Orthopedic Surgery.
