One of the greatest rewards in practicing medicine is successfully treating and alleviating a patient's illness – but first, we often face a challenging and complex diagnostic process when our patients suffer from rare and ambiguous ailments.
Some patients may have symptoms caused by a variety of issues, while others may have multiple symptoms caused by a single, underlying condition. As providers, we can identify this important distinction through careful observation and medical testing, which admittedly can be a tiring and frustrating process for patients as we analyze the body for root causes of symptoms and discomfort.
We can best support and help our patients by viewing the human body holistically as an interrelated, single-functioning unit. As is commonly known, many of the body's organs and involuntary activities are controlled by the autonomic nervous system (ANS). Given the ANS' pervasive influence and reach throughout the body, it is not surprising that dysfunction throughout the ANS is quite frequent and can manifest in numerous chronic conditions with common symptoms such as syncope, dizziness, gastroparesis and sweating abnormalities, to name a few. Thus, a "dysautonomia" can result from a collection of nerve disorders and diseases, creating a number of malfunctions across the ANS. Because of this complexity, a diagnosis of "dysfunction of the ANS" can be challenging.
Complicating the matter is that autonomic symptoms frequently are the first manifestations of serious underlying causes, such as vitamin deficiencies, autoimmune diseases, abnormal protein buildup in the blood, metabolic and infectious diseases, degenerative neurological diseases such as Multiple System Atrophy and can mimic mood disorders. Therefore, under-recognizing these symptoms as ANS-related for long periods of time – often years – can result in increasing disability (sometimes irreversible) due to the underlying causes remaining undiagnosed and untreated. Because of the prolonged absence of diagnosis and the resulting significant increase in anxiety levels, it is not uncommon for a patient's symptoms to be attributed to psychosomatic disorders, which often results in substantial moral detriment.
An alternative and, at times, very effective approach to help these difficult-to-diagnose patients may lie in autonomic testing. While autonomic testing is relatively new, it is a valuable tool to aid clinicians in making accurate diagnoses and identifying a primary or disease-based dysautonomia. Autonomic testing can qualitatively and quantitatively detect a dysfunction of the ANS and determine the location of the lesion in the nervous system, enabling physicians to clearly identify the nature of the problem, determine the most appropriate etiological work-up and establish an appropriate treatment plan for each patient.
It is estimated that an underlying disorder can be found in 30 to 50 percent of autonomic neuropathy cases and in most cases, we can treat effectively this primary cause. Improving the outlook for patients is powerful and promising – especially for patients with highly prevalent conditions, such as the 9.3 percent of the American population estimated to have diabetes. Studies have shown that approximately 17 percent of patients with type 1 diabetes and 22 percent of those with type 2 diabetes suffer from cardiovascular autonomic neuropathy. A comprehensive, accurate treatment plan for these diabetes patients, for instance, would include the analysis of the root cause of the autonomic dysfunction as well as a care plan for the symptoms of autonomic neuropathy.
Despite a growing need, comprehensive autonomic testing remains a relatively rare healthcare offering. Hospitals that do offer it typically provide a range of capabilities within the categories of cardiovagal, adrenergic and sudomotor tests. It is important to note that not all tests are conducted for each patient, but rather an individual's symptoms dictate a personalized testing process. Some of the most common tests performed in a lab include the Heart Rate Variability test, the Valsalva maneuver, the Tilt Table Test to evaluate unexplained fainting and the Quantitative Sudomotor Axon Reflex Test (QSART) to measure the integrity of the nerves that control sweating.
If the four initial tests reveal evidence of a problem with a patient's ANS that is not clearly identified, physicians have additional tests at their disposal, such as Thermoregulatory Sweat Testing to measure sweat ability and patterns; Laser Doppler Flowmetry to evaluate microcirculatory blood flow in tissue; or Infrared Dynamic Pupillometry to test the integrity of the sympathetic and parasympathetic branches of the ANS at the pupil.
Combining autonomic tests in a customized way for each patient can help healthcare providers solve some of the most challenging diagnostic mysteries. For example, if a patient has a non-length-dependant autonomic and/or somatic small fiber neuropathy with specific clinical symptoms, tests can be performed to rule out Sjögren's syndrome or amyloidosis. Also, if a patient is experiencing symptoms of fibromyalgia, chronic fatigue, migraine, brain fog and orthostatic intolerance, a tilt table test may diagnose the Postural Orthostatic Tachycardia Syndrome (POTS).iv Last but not least, in the Complex Regional Pain Syndrome (CRPS), sweat testing can uncover novel mechanisms of this poorly understood condition and enable potential treatments.v
A couple of years ago, I treated a nurse who experienced debilitating symptoms – heartbeat irregularity, syncopal episodes, severe tachycardia, dizziness, to name a few – for more than 25 years without conclusive diagnostic success. She visited multiple specialists who attributed her symptoms to stress and adrenergic hyperactivity, and she was ultimately diagnosed and treated for POTS in 1995. However, since her intense symptoms and bouts of being bed-ridden continued until 2012, her neurologist recommended she undergo autonomic testing.
Through a series of autonomic tests, positron emission tomography scans, blood work and nerve/muscle fiber biopsies, it was determined that in addition to suffering from POTS, she had an autonomic neuropathy and a generalized dysfunction of her ANS. We were able to diagnose two additional critical conditions – Sjögren's syndrome and Hashimoto's thyroiditis (an autoimmune disorder of the thyroid gland). The coexistence of these two conditions concluded to the presence of a systemic autoimmune disorder as the origin of her long-standing dysautonomia and brought an answer to more than a two-decade search for a diagnosis. We started her on a personalized treatment with Intravenous Immunoglobulins (IVIG) which, when combined with her POTS treatments, quickly minimized her symptoms and dramatically improved her quality of life.
Reducing the amount of time that patients suffer from unknown causes is critical to our mission as healthcare providers. To do so, we should further support scientific research on disorders of the ANS, train Residents and Fellows in autonomic diseases and advocate for advanced high-quality autonomic testing capabilities in our hospitals. These tools enable qualified healthcare providers to more accurately and quickly diagnose and can result in improving the lives of millions of Americans suffering from dysautonomia.
Dr. Chémali earned his medical degree from the Lebanese University Faculty of Medical Sciences after also attending medical school at the Facultés Universitaires Notre-Dame de la Paix in Namur, Belgium. He completed internships at the Lebanese University Faculty of Medical Sciences and Staten Island University Hospital, and his neurology residency at University Hospitals of Cleveland and Case Western Reserve University. Dr. Chémali then completed fellowship training in Clinical Neurophysiology, Electromyography and Neuromuscular Diseases at Cleveland Clinic.
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