Updated Saturday, November 3, 2012 at 12:16 AM
Just when they thought they were in the clear, people recovering from meningitis in a national outbreak caused by a contaminated steroid drug have been struck by a second illness.
The new problem, called an epidural abscess, is an infection near the spine at the site where the drug — contaminated by a fungus — was injected to treat chronic back or neck pain. The abscesses are a localized infection, different from meningitis, which affects the membranes covering the brain and spinal cord.
But in some cases, an untreated abscess can cause meningitis. The abscesses have formed even while patients were taking powerful antifungal medicines, putting them back in the hospital for more treatment, often requiring surgery.
The problem has just begun to emerge, mostly in Michigan, which has had more people sickened by the drug — 112 of 404 nationwide — than any other state.
"We're hearing about it in Michigan and other locations," said Dr. Tom Chiller, deputy chief of the mycotic-diseases branch of the Centers for Disease Control and Prevention (CDC). "We are just learning about this and trying to assess how best to manage these patients. They're very complicated."
In the past few days, about one-third of the 53 patients treated for meningitis at St. Joseph Mercy Hospital in Ann Arbor, Mich., have returned with abscesses, said Dr. Lakshmi Halasyamani, the chief medical officer.
"This is a significant shift in the presentation of this fungal infection, and quite concerning," she said. "An epidural abscess is very serious."
She and other experts said they were especially puzzled that the infections could occur even though patients were taking drugs that, at least in tests, appeared to work against the fungus causing the infection, a type of black mold called Exserohilum rostratum.
The main symptom is severe pain near the injection site. But the abscesses are internal, with no signs on the skin, so it takes an MRI scan to make the diagnosis. Some patients have more than one abscess. In some cases, the infection can be drained or cleaned out by a neurosurgeon.
Some patients have had epidural abscesses without meningitis; St. Joseph Mercy Hospital has had 34 such cases.
A spokesman for the health department in Tennessee, which has had 78 meningitis cases, said a few cases of epidural abscess had also occurred there, and the state was trying to assess the extent of the problem.
Chiller said doctors were also reporting that some patients exposed to the tainted drug had arachnoiditis, a nerve inflammation near the spine that can cause intense pain, bladder problems and numbness.
The meningitis outbreak, first recognized in late September, is one of the worst public-health disasters caused by a contaminated drug. So far, 29 people have died. The drug was a steroid, methylprednisolone acetate, made by the New England Compounding Center in Framingham, Mass. Three contaminated lots, more than 17,000 vials, were shipped around the country, and about 14,000 people were injected.
The compounding center has been shut down, as has another Massachusetts company, Ameridose, with some of the same owners. Both companies have had their products recalled.