San Diego—As the number of fungal meningitis cases linked to contaminated steroid injections rise, information about the outbreak and diagnosing and treating the infection continues to emerge.
Since the initial report on September 21 to the US Centers for Disease Control and Prevention (CDC) of meningitis in a patient who had recently received a spinal injection of steroids, a steady rise in cases reported in a number of states made it clear the problem was far from an isolated problem.
At a special session of the IDWeek 2012 conference last night, Tom M. Chiller, MD, MPHTM, deputy chief of the CDC’s Mycotic Diseases Branch, offered the audience updated numbers and recommendations. As of October 18, 257 infections have been reported in 16 states. Cases included 254 central nervous system infections (meningitis and/or spinal abscess) and 3 infected joints. Twenty patients have died from these serious infections.
Investigators are learning more about the microbiology of these infections, notably that nearly all of the fungal isolates identified so far are Exserohilum rostratum. Chiller described the initial challenges surrounding diagnosis, especially because cultures from the patient who was first identified with the infection grew a different and much more common fungal pathogen, Aspergillus fumigatus. The CDC has now developed a novel polymerase chain reaction test to specifically identify this organism during the outbreak.
Although Exserohilum, a brown-black mold commonly found in soil, has occasionally caused widespread infection in patients with compromised immunity, infection in healthy hosts has been limited to localized infection. According to the CDC, Exserohilum has not previously been reported to cause disease in the central nervous system. A similar black mold, Exophiala, caused a similar but more limited outbreak in 2002 that also was associated with contaminated steroid injections manufactured at a compounding pharmacy.
Among the first 70 cases, Chiller said, the average age was 68 years and two-thirds were women. Meningitis has been the most common clinical presentation (91%), and in many of the more recent cases, patients have presented with relatively mild symptoms, likely because they are seeking medical attention much sooner. Chiller advised clinicians to be aware of atypical presentations and emphasized the need for close monitoring of patients who had been exposed to the contaminated steroid who initially tested negative for infection but who had persistent symptoms. Repeat testing has shown abnormalities in several cases.
Expert panelists Thomas A. Patterson, MD, of the University of Texas Health Science Center, San Antonio, and Carol A. Kauffmann, MD, of the University of Michigan, Ann Arbor, offered guidance on treatment and management. Current recommendations suggest the use of high-dose voriconazole. Clinicians can consider adding liposomal amphotericin B in patients with severe infection or those with progressive disease, they said, but both of these agents have significant toxicities, making careful monitoring imperative. How long treatment should last is unknown but will likely depend on clinical response and the development of complications, including bone involvement. Prophylaxis of exposed but asymptomatic patients is not recommended, the panel said, because the drugs are not well tolerated and have numerous drug interactions.
All 3 panelists emphasized that the outbreak is dynamic and that guidance on managing patients continues to evolve as additional details unfold. Clinicians must be vigilant not just during the coming days and weeks but for months, they said.
For More Information
JAMA is providing updated information for both clinicians and patients, available online:
Information for Physicians: http://jama.jamanetwork.com/SS/fungal_meningitis_outbreak.aspx#info_clinicians
Information for Patients: http://jama.jamanetwork.com/SS/fungal_meningitis_outbreak.aspx#info_patients
Other Useful Resources:
US Centers for Disease Control and Prevention. Multistate Fungal Meningitis Outbreak Investigation. http://www.cdc.gov/hai/outbreaks/meningitis.html
US Food and Drug Administration. FDA Statement on Fungal Meningitis Outbreak. http://www.fda.gov/Drugs/DrugSafety/ucm322734.htm