By TOM WILEMON THE TENNESSEAN
ATLANTA - Laboratory tests have confirmed additional bacterial and fungal contaminants in drugs made by New England Compounding Center, the Massachusetts pharmacy responsible for the batch of moldy medicine linked to the fungal meningitis outbreak.
The U.S. Centers for Disease Control and Prevention issued an alert to health care workers Monday night of the contamination in cardioplegia, a drug used in heart surgeries, and the steroid medications betamethasone and triamcinolone.
Contaminants detected in unopened vials include the bacteria Bacillus, fungal species Aspergillus tubingensis and Asbergillus fumigates and two other fungi, Cladosporium and Penicillium. At this point, all cases of fungal meningitis have been traced to preservative-free methylprednisolone acetate distributed by the compounding pharmacy.
Bacillus species and Aspergillus fumigates are known to cause disease in humans. The CDC said that although it has received reports of illnesses in patients who took medications other than methylprednisolone acetate, including some who had evidence of meningeal inflammation, there had been no laboratory-confirmed infections.
The agency advised doctors to be alert for the possibility of infections and consider ordering bacterial and fungal cultures if they suspect an infection.
New England Compounding Center recalled three lots of methylprednisolone acetate on Sept. 26 then all of its products on Oct. 6.
The CDC continues laboratory tests on brain tissue from some of the patients who died of fungal meningitis. Clifton Drew, a staff pathologist with the CDC, said that while it had already had frozen brain tissue samples of Aspergillus meningitis, it had none for Exserohilum meningitis before the outbreak. Exserohilum meningitis was a new disease in humans spawned by the contaminated medicine.
Dr. John Jernigan, the Tennessee native and Vanderbilt-educated epidemiologist who leads the CDC team on the meningitis outbreak, spoke about the difficulty of treating patients with the new form of meningitis Monday night at a meeting hosted by the Atlanta chapter of the Association of Health Care Journalists. Although the anti fungal medication Voriconazole has proven effective with patients who are treated early, doctors remain uncertain about how long patients should continue to take the drug, he said. Patients are taking the oral form of the drug once released from hospital.
"We actually haven't given an upper limit of the recommendation," Jernigan said. "We said 'for months.' Three months for starters . . . But quite honestly it is probably going to be longer than that in most cases."
Patients have to take higher doses of Voriconazole because of the blood-brain barrier, a natural defense mechanism of the body that makes it more difficult to target the brain with medicines, he said.
Several mysteries remain about the outbreak, including why fungal contaminants caused meningitis instead of bacterial contaminants and why no infections have been reported in some states, including California, that received methylprednisolone acetate. As of Monday, the outbreak had caused 541 illnesses nationwide, including 36 deaths. Tennessee's 13 deaths are the most of any state at this point, although Michigan has the most cases with 198 compared to 88 in Tennessee.