Medical testing today can reveal amazingly detailed results, yet many chronically ill people have standard test results that appear normal. In spite of this disconnect, doctors put tremendous trust in the integrity of medical tests and many render judgement and diagnoses based solely on test results alone. This is especially the case when utilizing tests considered the “gold standard”. Most doctors believe these test render results that are irrefutable.
But what happens when the tests aren’t conducted, handled, or processed properly? How about when the gold standard isn’t all it is knocked up to be? What if that result that is just somewhat out of the normal range is really an indicator of a greater underlying issue? Is too much faith being put in the test results and “normal” ranges, even when those results don't align with patients' symptoms?
Patients are often left undiagnosed and untreated when these things occur, especially those with rare genetic abnormalities or elusive diseases. A prime example of a frequently flawed test is the basic blood test given to check electrolytes. This is a standard test rendered in emergency rooms and hospitals across the country on a daily basis, with a nurse or technician utilizing a tourniquet to make it easier for them to find a good vein. In fact, the use of a tourniquet has become such a standard practice that requesting no tourniquet be used for a blood draw is often met with argument, condescension, and refusal. However, that standard practice has been proven to falsely elevate potassium results by as much as 20%, as well alter glucose results to a lesser degree. Heck, even shaking the vial of blood after it is drawn is enough to alter potassium results. This is common knowledge among Phlebotomists, but not among many of the nurses and technicians who conduct the blood draws or the doctors rendering diagnoses based on those test results.
For those with conditions associated with hypokalemia, this disparity falsely masks debilitating and potentially life threatening medical conditions. An example of such a condition is Hypokalemic Periodic Paralysis, which is an ion channelopathy triggered by shifts in serum potassium. This condition can affect a patient cognitively as well as render them unable to move an isolated muscle group, profoundly weak, and often completely paralyzed and unable to make sound, move their mouth, or open their eyelids. During a full paralysis attack they remain completely conscious, aware of everything going on around them and able to feel physical touch. Many individuals with this class of conditions often go many years, even decades, without diagnosis or treatment simply because of the now prolific use of tourniquets when doing blood draws which masks hypokalemia except in extreme cases. To compound the difficulty of diagnosis, the potassium can return to the normal range by the time the patient gets to an ER even though their muscle function remains impaired.
Another instance in which a diagnosis is missed due to a misplaced trust in testing is the highly specialized electromyogram (EMG), often referred to as the gold standard for testing electric activity in muscles. This test can be very informative in many instances and is often looked to as providing definitive proof of whether or not muscle related disorders are present. And yet, even this test is flawed. When used to test for Periodic Paralysis, the EMG has a success rate of detecting the condition only 20% of the time. In spite of this dismal record in relation to detecting that specific ion channelopathy, doctors still look to that test as a means of ruling out the presence of Periodic Paralysis. A hybrid version of that test which is almost never considered by doctors, the Compound Muscle Action Potential (CMAP) test (also referred to as the Exercise EMG or Motor Conduction Studies), has an 80% success rate in identifying the existence of Periodic Paralysis. Although that is a significant improvement, that still leaves 20% of patients with that specific condition to fall through the cracks based on that hybrid version of a gold standard test. In that instance, a negative result is still clearly not enough to rule out the condition altogether but frequently incorrectly assumed to do so by many doctors.
Unfortunately, a layperson offering information of this nature to those with a medical background is often considered no more than a nuisance. Too often they are disregarded out of hand or met with condescending responses, like being told not to believe everything they read on the Internet. This type of response is based on the broad assumption that a layperson certainly couldn’t be consulting highly respected medical journals, peer reviewed medical studies, or in contact with numerous others who have already been accurately diagnosed with the rare condition. Some medical professionals, however, choose to take a less abrasive approach and simply placate these individuals, simply pretending to believe them in the moment but in fact disregarding the unsolicited input altogether. Precious few doctors welcome and encourage this input, and patients are incredibly grateful and relieved when they come across them in the course of seeking care.
If medical personnel took just a moment to seriously consider these nuggets of knowledge when offered, asking for a link to that information or a printed copy, I believe a great deal of time and money could be saved. Additionally, patients could potentially benefit by receiving more accurate and timely care. After all, patients generally only have one patient they are focused on with a specific set of symptoms. Why not allow them the opportunity to act as a medical research assistant on their own behalf? I believe many doctors might be surprised at how often it proved beneficial to all the stakeholders involved.