In previous blog articles, I discussed the multistate outbreak of fungal meningitis caused by tainted steroid injections. Now more than nine weeks since the outbreak was announced, and the number of infected individuals continues to rise. However, there is a new trend in the manifestation of infection in affected patients: when previously health officials reported meningitis as the primary disease, a majority of the most recent victims were diagnosed with epidural abscess.
An epidural abscess is an accumulation of puss that forms within the spinal canal and surrounds the spinal cord. If an epidural abscess remains undiagnosed or treated, the patient is at great risk of suffering compression of the spinal cord or nerves exiting the spinal cord. This compression can cause severe back pain, neurologic changes in the lower extremities and bowel or bladder dysfunction. If left untreated, a spinal epidural abscess could cause paraplegia.
In a November 20, 2012 Health Advisory, the Centers for Disease Control and Prevention (CDC) explain that of 91 cases of meningitis and other infections reported since November 4, 2012, 26 (29%) were classified as meningitis and 61 (67%) were classified as spinal or paraspinal epidural abscess or osteomyelitis. Figure 1 below is an illustration from the CDC website demonstrating the shift trend of infection from meningitis to osteomyelitis/abscess.
Fortunately, the CDC recognizes the need for a heightened sense of awareness that patients infected by the tainted steroids may develop an epidural abscess. The CDC set forth diagnostic treatment guidelines reminding clinicians that when patients with baseline chronic pain (like many of those who received steroid injections in the first place) who experience new or worsening back pain, physicians should obtain an MRI with contrast of the symptomatic area(s). Clinicians are also advised to maintain a low threshold for repeat MRI studies in patients whose symptoms persist at the sight of injection, even after a normal MRI. The concern for developing epidural abscess is significant enough that the CDC recommends clinicians obtain an MRI approximately 2-3 weeks after diagnosis of fungal meningitis, even in the absence of new or worsening symptoms. This guideline is no doubt in response to reports of patients who were treated in hospitals for meningitis, discharged, yet return several weeks later with complaints of back pain later diagnosed as epidural abscesses. Neurology Today, December 6, 2012.
Meanwhile, the total number of infections related to the outbreak continues to rise. On November 14, 2012, the total was 461 cases. As of December 10, 2012, the CDC is reporting 590 cases have been reported, including 214 in Michigan alone.