National national attention has recently been focused on the issue of epidural steroid injections (ESIs) because of the use of steroids containing fungal contaminants resulting in fungal infectious meningitis. Epidural steroid injections are commonly performed as an early treatment for low back pain.
As of November 24, 2012 the Center for Disease Control had identified 478 cases of fungal meningitis and 34 deaths due to this steroid contamination in the United States.
Remarkably, a much more serious widespread health care problem related to epidural steroid injections has received essentially no attention from the medical community or governmental agencies. This has been specifically related to inadvertently causing a severe chemical meningitis when some sterile steroid suspensions are unknowingly injected, not into the epidural space, but directly into the spinal fluid (the subarachnoid space).
The subarachnoid space which surrounds our nervous systems (brain, spinal cord, etc.) contains the cerebro-spinal fluid (CSF) and is the most fragile and pristine environment in the human body. It does not well tolerate irritants or toxic materials. It is the last place where toxic chemicals should be placed due to the intolerance of the surrounding tissues leading to an inflmmatory reaction referred to as “arachnoiditis” which, if progressive, can produce severe scarring, a condition referred to as “adhesive arachnoiditis”. This inflammatory condition is capable of producing permanent injury to the spinal nerves of the cauda equina which is typically reflected by associated intractable and constant pain which can be totally disabling. Unlike bacterial or fungal meningitis, which can lead to death, chemical meningitis rarely produces death but often results in totally disabling life-long chronic pain.
During the early 1940s oil based myelographic agents (pantopaque and myodil), which had not received drug approval were introduced for routine use in military hospitals by a Army officer who, along with his associates, had personally received a patent for Pantopaque. Even though neurosurgeon William Van Wagenen identified Pantopaque as the cause of “chemical meningitis on” in the spine it was marketed throughout the world, and at the height of its use is estimated that thousands of servicemen and approximately 450,000 patients a year received Pantopaque myelogramsa year in the U.S. . The fallout from this was hundreds of thousands of totally disabled individuals. Pantopaque was never banned from use in the US but fortunately was replaced by safer myelographic substances in the 1970 at which time it “fell into disuse.”
The serious problems relating to chemical meningitis secondary to Pantopaque were never really effectively made known to the medical profession and, because of this, many practitioners have not become aware of this history. This can not, however, be considered a legitimate excuse by those whose ignorance is placing their patients at high potential risk.
Following the initial use of the steroid cortisone in medicine in 1949 epidural steroid injection became popular as a means of treating low back pain. Steroid solutions such as hydrocortisone, methylprednisolone, triamcinolone, and betamethazne along with suspensions containing other substances came into routine use. It is interesting to note that although double-blinded randomized and prospective studies generally failed to support the efficacy of epidural steroid injections even their detractors continued to use this procedure on a regular basis and there is no doubt, that when used safely, that epidural steroid injections have withstood the test of time as a valuable adjunct in the treatment of low back and leg pain.
Steroids by themselves are rarely associated with inflammatory reactions or chemical meningitis. In fact steroids tend to be a first line of defense in treating inflammatory conditions. The same, however, cannot be said to be true in regard to the associated substances often added to the steroid solutions intended to prolong shelf life and to decrease absorption. The most commonly used steroid for epidural injection has been methylprednisolone combined with stabilizers such as polyethylene glycol in suspensions such as Depo-Medrol. Research has shown that the prime offender in causing conditions such as chemical meningitis leading to adhesive arachnoiditis has been the polyethylene glycol component in suspensions such as Depo-Medrol. One solution is to simply inject solutions rather than suspensions. It must be pointed out that not infrequently, in the past, safer solutions have not been available for practitioners to use. Compounding pharmacies have provided an important service in making safer steroids more available with better and cost-saving packaging. This does not, however, excuse poor quality control allowing product contamination.
Due to the high risk level it is essential that steroid suspensions be reliably deposited into the epidural space and do not enter the subarachnoid space. Unless the procedurist performing the epidural steroid injection utilizes the safeguards of fluoroscopic monitoring and epidurography to safely guide the needle clinical studies document that in approximately 30% of cases the needle is not where the procedurist thinks it is. Typically, this problem occurs with “blind” epidural steroid injections performed by practitioners ignorant of the potential complications and thus unable to provide their patients with adequate informed consent. True informed consent is not possible when the physicians performing epidural steroid injections are themselves ignorant of the potential adverse consequences of their actions. Shown below is a popular patient hand-out on “Lumbar Epidural Injections” originally published in 1998.which does not even mention chemical meningitis, or its sequela, as possible complications:
Even more remarkable is the following comprehensive review on Epidural Steroids published by the prestigious North American Spine Society in 2003, also failing to even mention chemical meningitis as a possible complication:
Checklist To Follow Before Ever Having A Epidural Steroid Injection
- Become a well-informed consumer and always seek informed consent.
- Request a specific diagnosis before ever agreeing to have any form of invasive therapy.
- Always inquire if alternative non-invasive therapies are available.
If an epidural steroid injection is being recommended inquire regarding the type of technique being used and the specific steroid being used. Always avoid having a blind injection performed.