Ending the diagnostic journey for patients, particularly those with rare diseases, improves patients’ quality of life while reducing costs to healthcare systems.
For patients suffering from complex diseases, the journey from diagnosis to treatment can be a long, costly endeavor that can last for years. This is especially true for those with rare genetic diseases. According to the National Center for Advancing Translational Sciences (NCATS), many patients wait for several years to receive a diagnosis. This journey is often referred to as the diagnostic odyssey.
According to the National Institutes of Health (NIH), rare diseases affect an estimated 30 million children and adults in the United States. While the total medical care costs are around $400 billion for these diseases, diagnostic delays also cost time. The delays in arriving at a diagnosis not only burden patients with unnecessary testing and potential misdiagnoses but may lead to irreversible damage as their conditions go untreated. Given the difficulties that many healthcare providers and patients have faced trying to receive answers, organizations such as the NIH have committed funding to research projects specifically dedicated to the patient odyssey.
One rare disease is myotonic dystrophy type 1 (DM1), a multisystem disorder that can affect muscles including the heart as well as the central nervous system, eyes, endocrine system, and other parts of the body. There are several forms of DM1, the most severe of which presents with symptoms at birth and can lead to life-threatening symptoms during infancy. Even in more mild cases, not having a diagnosis can lead to unmanaged muscle weakness, cataracts, and other symptoms. DM1 can present similarly to many other conditions which makes diagnosis in many cases difficult.
Navigating Symptoms
Dr. Christine Eng, a pediatric geneticist and the chief medical officer at Baylor Genetics, explained that rare genetic diseases may often present with evolving symptoms during the newborn period, childhood,
adolescence and adulthood as the condition progresses. Physicians are often left to attempt diagnosing patients with “symptoms that may not be classic or easily recognizable for the condition,” she said.
As an additional complication, some rare diseases present with combinations of symptoms. For example, Eng explained that a condition called TANGO2 deficiency presents with “a constellation of symptoms such as developmental delay, intellectual disabilities, speech problems and muscle weakness”. This is a condition that is fatal in half of children diagnosed. However, the symptoms of TANGO2 deficiency are similar to those associated with heart problems, metabolic problems, and hypothyroidism, leading to the condition being widely under-recognized. This array of symptoms often leads “physicians to refer to a subspecialist, which is commonly a neurologist or cardiologist, or other specialists,” Eng said, who may then refer the patient for genetic testing.”
Comprehensive Genomic Testing Lights the Way
Patients with TANGO2 deficiency, like those with many other rare diseases, can be on the diagnostic odyssey for many years. This does not need to be the case, however. Eng stated that a diagnosis can be made after comprehensive genetic testing is performed. “Often patients are in a waiting state for months awaiting results from multiple tests while their condition is being managed. Whole genome sequencing, or WGS, can return results in as little as five days, which grants patients valuable time needed for more specific or urgent management.”
Besides the cost savings for patients and the healthcare system, a whole genome sequencing test can return valuable time to the patients, which is essential for difficult to diagnose genetic diseases. “Currently, rapid testing, which returns written results in five days is mainly reserved for acute care settings.” Eng pointed out that whole genome sequencing is also available for other patients as well. “At Baylor Genetics, we have been able to reduce the turnaround time to just three weeks for patients who come into subspecialty outpatient clinics.” She explained that the primary focus is on getting patients, caregivers, and clinicians the answers they need as soon as possible.
“As technology and science advance, we have the tools to improve the patient’s experience with diagnostics such as whole genome sequencing—which can take the place of multiple genetic tests—as part of standard care,” Eng said.
As early as 2018, the United States started using whole genome sequencing to diagnosis complex diseases. Eng noted that equalizing healthcare access is still an ongoing dialogue both locally and on a global scale.
“The more this testing becomes standard of care across healthcare systems, I think that that’s going to be a game changer in addressing the health disparities that we currently see in the United States and globally,” she stated. “Instead of spending time searching for a diagnosis, healthcare providers can concentrate on the management of the condition.”
It is a different approach, one focused on outcomes and planning for what comes next. Eng reinforced that instead of being in a period of diagnostic uncertainty, having a diagnosis in hand enables physicians to be proactive. “They are making sure they are preparing the patients for the best possible outcome.”
This article was written in collaboration with Baylor Genetics.
