The autonomic chamber conducts a diagnostic test called a thermoregulatory sweat test to help diagnose neuromuscular diseases.The University of Alabama at Birmingham has opened the seventh comprehensive autonomic testing laboratory in the United States. The autonomic nervous system controls involuntary functions of the human body, including heart rate, breathing, coughing and sweating. Sweating — or more accurately, not sweating — is one of the keys to diagnosing conditions affected by the autonomic nervous system.
The lab, the only comprehensive such facility in the Southeast, can assist physicians in the diagnosis of conditions associated with autonomic function, including disorders of the peripheral nervous system such as painful small fiber neuropathies, diabetic autonomic neuropathy and neuropathies associated with connective tissue disorders. It is also useful for some central nervous system disorders including parkinsonian syndromes like multiple system dystrophy and Lewy body dementia. It also has utility in diagnosing complex regional pain syndrome.
“With the sophisticated testing available in the lab, we will be better able to provide a definitive diagnosis for these autonomic conditions that often prove hard to diagnose,” said Mohamed Kazamel, M.D., assistant professor in the Department of Neurology. “Providing accurate diagnosis helps a referring physician prepare a treatment plan focusing on treating the cause of disease instead of simply managing symptoms. Ultimately, this lab can provide the accurate diagnosis required to create precise and targeted therapies for autonomic conditions.”
The lab boasts two distinct diagnostic tools. A tilt table is used to measure different cardiac functions. It can induce stress on the cardiac system and measure the reaction from small nerve fibers that regulate heart rate and blood pressure, which can provide clues useful in diagnosis.
The control panel regulates temperature and humidity.The second tool is unique. Known as an autonomic chamber, it performs a diagnostic test called thermoregulatory sweat test.
“A hallmark of autonomic conditions is an inability to sweat in different parts of the body,” Kazamel said. “The thermoregulatory sweat test can precisely measure the body’s ability or inability to sweat, which is invaluable in determining a diagnosis. Many academic medical centers have a tilt table, but only the seven comprehensive labs have the TST chamber.”
The chamber, designed and built with cooperation from Case Western Reserve University in Ohio, a leading autonomic disease center, is a sealed enclosure roughly 11 feet long, 4 feet wide and 9 feet high — large enough for a hospital bed. Patients are coated with alizarin powder, which changes from a sandy yellow color to purple when exposed to sweat. The device is designed to slowly and safely raise the temperature and humidity in the chamber to induce sweat. Determining the distribution of the body areas that do not sweat is key to proper diagnosis.
“Changes in the color of alizarin powder correlate to specific disease,” Kazamel said. “Patients with neuropathy don’t experience sweat on their feet, for example. Patients with multiple system atrophy don’t sweat at all.”
Kazamel says the new lab will be available to referring physicians across Alabama and the region. He anticipates most referrals will come from neurologists, cardiologists, gastroenterologists, primary care and internal medicine physicians. The lab began seeing patients May 15.
Physicians interested in learning more about the autonomic lab should go to the lab’s website.