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An urgent brain CT was ordered but appeared normal.

A cervical spine radiograph showed an increased atlantoaxial (C1-C2) distance of 5 mm.

However, MRI showed a septic arthritis from C1-C2 with enhancement of the dura.

There was no evidence of bony destruction or spinal cord compression.

Although any infectious agent may cause arthritis, bacterial pathogens are the most significant because of their rapidly destructive nature.

For this reason, the current discussion concentrates on bacterial septic arthritides.

Failure to recognize and to appropriately treat septic arthritis significantly increases morbidity and may even lead to death.

According to Dr. Sarah Westlake, who is a rheumatology specialist registrar at Queen Alexandra Hospital in Portsmouth, (England), only two patients previously have been described with C1-C2 septic arthritis.

“As in our patient, early radiograph features of prevertebral soft tissue swelling can be very subtle and bony destruction of septic arthritis or endplate destruction of diskitis can take 2-8 weeks to evolve,” she said.

Cervical septic arthritis or diskitis can be life threatening. That is because there is a heightened risk of cervical spine subluxation as well as medullary compression.

“It should therefore be considered in any patient with sepsis and severe neck pain, even with normal cervical spine radiographs,” she explained.

MRI and blood cultures are the diagnostic tests of choice.

However, if the blood cultures turn out to be negative, diskovertebral biopsy for diskitis or joint aspiration for septic arthritis could be considered by a suitably-trained radiologist, said Dr. Westlake.

Blood cultures were performed on this patient on three separate occasions. The subsequent cultures grew methicillin-resistant S. aureus.

“S. aureus is the most common organism causing nongonococcal arthritis. The virulence of S. aureus is associated with its ability to attach to host tissue within the joint, evade host defenses, and cause damage to the joint,” according to Kelley's Textbook of Rheumatology, 7th edition.

The patient was treated with a 6-week course of vancomycin and an additional 6 weeks of rifampicin and doxycycline.

There were no neurologic complications that occurred at any time.

Septic arthritis from C1-C2 is seen (arrow), with enhancement of the dura. Courtesy Dr. R. Hull/Dr. S. Westlake/Dr. F. Witham