Multiple reports emerged back in September 2012 of meningitis in patients following otherwise routine steroidal injections.
As of June 2013, 745 people have been infected and 58 have died – primarily along the eastern half of the US from New Hampshire to Florida – as a result of contaminated epidural, paraspinal, and intra-articular injections.
Patients acquired fungal meningitis.
Based on CDC data, Michigan and Tennessee have been hardest hit from this outbreak with the highest number of infections and fatalities.
Fungal meningitis, which is rare, occurs when the protective membranes covering the brain and spinal cord are infected with a fungus. Fungal meningitis is not contagious, which means it is not transmitted from person to person. This type of meningitis develops after a fungus spreads through the bloodstream from somewhere else in the body, or as a result of the fungus being introduced directly into the central nervous system.
An investigation by the FDA and CDC traced the source of the contaminants to more than 17,000 vials of polluted lots of preservative-free methylprednisolone acetate (MPA), all originating from a single pharmacy.
The medication had been contaminated by a fungus, introduced during production at the New England Compounding Center – a company that has since had to file for Chapter 11.
During an October 2012 investigation of the facility, the FDA found condensation and discoloration on the autoclave which had been used to sterilize the steroid injections as well as other drugs, reports CBS News. Investigators also found a greenish-yellow lining on the viewing lens of one of two autoclaves used to steam equipment.
Fifty vials were collected and sent by the FDA to a lab and tested. All 50 confirmed the presence of foreign microbial growth.
Despite months of antifungal treatment, the patients who contracted fungal meningitis from tainted injections of methylprednisolone will face the possibility of relapse, reports NBC News. During this outbreak, some patients developed spinal or paraspinal infections at the injection site, such as epidural abscess or arachnoiditis.
A spinal epidural abscess is characterized by inflammation, pus, and swelling in the affected area. Common symptoms can include fever, headache, back pain, and neurological problems.
Arachnoiditis is a disorder caused by the inflammation of the arachnoid, one of the membranes that surrounds and protects the nerves of the spinal cord. Symptoms of arachnoiditis include numbness, tingling, and burning pain in the lower back or legs.
Some people can suffer from debilitating muscle cramps, twitches, or spasms. The condition can also affect the bladder, bowel, and interfere with sexual function. In severe cases, paralysis of the lower limbs can result.
Investigators from the Centers for Disease Control and Prevention (CDC) describe pathologic findings from 40 confirmed case reports of fungal infection in patients who were dosed with polluted shots. Clinical laboratory data, which will be published in the September issue of The American Journal of Pathology, describes the catastrophic hazards associated with contaminated epidural injections.
Tests run by the FDA and CDC identified bacterial and/or fungal contamination in unopened vials of betamethasone, cardioplegia, and triamcinolone solutions distributed and recalled from the New England Compounding Center (NECC). These include bacteria known as Bacillus, and fungal species including Aspergillus tubingensis, Aspergillus fumigatus, Cladosporium species, and Penicillium species.
It was determined more than 13,000 people had been injected with the adulterated drugs – most attributable to Exserohilum rostratum, a black mold. The pathogen was responsible for nearly all of the fatalities during the meningitis outbreak, which by November 3, 2012 had resulted in 404 cases with 29 fatalities.
Researchers – including the CDC’s Exserohilum Infections Working Group, alongside investigators from the Office of the Chief Medical Examiner, in Louisville, Kentucky and the Department of Pathology, University of Michigan, in Ann Arbor – reviewed the 40 cases and found 16 of them had been fatal.
The fungus responsible for the meningitis outbreak took an unusual route through the human body – moving upward through the spinal fluid to the brain, later invading the blood vessels, reports the Huffington Post.
Autopsies revealed the disturbing evidence of extensive hemorrhages and necrosis around the base of the brain and clots interfering with the basilar arterial circulation.
Tissue specimens from infected individuals showed inflammation of the thin membranes lining the brain, called leptomeninges, and blood vessel walls within the brain. Distinctive abnormalities were observed around blood vessels, and fungus was found around and within arterial walls.
Similar pathologic findings were seen at the epidural injection site, but the not in tissue samples taken from the heart, lung, liver, or kidney.
Science Daily states, in addition to characterizing the histopathology seen in this outbreak, the authors also provide practical information for pathologists, including an effect diagnostic method to detect the fungal infection in tissues. Polyfungal immunohistochemistry (IHC) in formalin-fixed paraffin-embedded tissues (FFPE) was found to be the most sensitive method. IHC identified fungus in 100 percent of cases.
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