Chapter 15: Rare Diseases Are Common
Why Are They Missed?
What do celebrities Justin Bieber, Céline Dion and Jameela Jamil have in common? They’ve all shared what it feels like living with a rare disease.
“Rare disease” is the term for a wide range of medical conditions that are each so uncommon, they’re often difficult to identify and treat. To be considered a rare disease in the US, it must affect fewer than 200 thousand Americans, approximately 0.05% of the population.
Until 2022, there wasn’t even an agreed upon definition beyond the mathematics. The resulting internationally endorsed recommendation, called the Operational Description of Rare Diseases, begins:
“Rare diseases include, but are not limited to, rare genetic diseases, rare cancers, rare infectious diseases, rare poisonings, rare immune-related diseases, rare idiopathic[1] diseases, and rare undetermined conditions.”
Talent, fame and fortune won’t fully protect you though money helps. Being able to hire the best physicians may shorten the time to getting diagnosed and treated, if a treatment can be found. For over 90% of rare diseases, no accepted treatment or cure exists.
In referring to rare disease patients, the preferred term is PLWRD which stands for People Living With a Rare Disease.
Why Rare Diseases Are Actually Common
There are many known rare diseases, almost 14 thousand. They represent two-thirds of all medical conditions. Approximately 30 million Americans are People Living With a Rare Disease (PLWRD) in the United States; 10 percent of the US population. Worldwide, conservative estimates suggest over 300 million people live with a rare disease.
So, while the odds of each rare disease are tiny, count every PLWRD and it’s a widespread phenomenon.
A rare disease can be classified many ways:
Source: It can be genetic, either a genetic mutation inherited from a parent or the alteration happens randomly. Approximately 80% of rare diseases have a genetic cause. For most people with a genetic rare disease, symptoms begin in childhood. It can be acquired, meaning exposure to an infection or toxin kicked it off, or it might be an autoimmune reaction, which is when your body’s defense system overreacts. Céline Dion’s medical mystery was caused by a rare autoimmune reaction. Justin Bieber’s was acquired. Jameel Jamil’s is inheritable, meaning it was passed to her by one of her parents.
Age of Onset: It can vary by age of onset. Congenital and inherited diseases are present at birth, but others can become active at any age; even genetic diseases may not become active until later. Jamil was diagnosed as a child. Bieber’s rare condition more commonly affects seniors. Dion was just in her 30s when her symptoms began.
Treatment: It can be treatable, curable or neither. Approximately 90% of known rare diseases have no approved treatment. All three celebrities are luckier than most; their conditions are treatable but only Bieber’s is potentially curable.
Justin Bieber has spent most of his life under the magnifying lens of millions of adoring fans and aggressive reporters. As a singer and actor, his voice, face and body are his essential work tools. Social media and tabloids dissect his health like it’s Fantasy Football. So, imagine his emotions when he suddenly developed a facial rash with paralysis and partial hearing loss. In 2022, he announced he was diagnosed with Ramsay Hunt syndrome in this video; and then “disappeared” for months. It’s a rare neurological disorder (~16,500 Americans each year) that presents with facial weakness or paralysis of one side of the face and a rash. It’s caused by a reactivation of a dormant varicella zoster virus (VZV), which more commonly triggers shingles and chickenpox. Bieber’s Ramsay Hunt diagnosis was especially unexpected because it usually affects adults over 60 years of age, like shingles. Ramsay Hunt syndrome is treatable; even curable if you catch it early enough. Bieber says the treatments and exercises were successful but hasn’t clarified if he’s cured or still being treated.
Why Rare Diseases Are Routinely Missed
The average time for an accurate diagnosis varies greatly. Some report it’s four to eight years, others say it’s much longer. Children’s diagnoses are typically delayed six to eight years –– which can really harm their physical and mental development and sense of self. It’s a terrifying stat since 30% of children with a rare disease die before they even reach five years of age. That’s devastating and avoidable. Diagnostic delay for rare diseases is also expensive, up to $517,000 in avoidable costs per patient.
It took 17 years for Céline Dion to identify why she would suddenly lose control of her voice or experience painful muscle spasms making walking hard, let alone performing. Doctors initially dismissed her symptoms. She described it as feeling as if someone was “strangling” her as she suffered broken ribs from spasms. Finally diagnosed, Dion announced that she had Stiff Person Syndrome (SPS) in December 2022. SPS is a rare, 1-in-a-million-person, autoimmune neurological disorder. Some types are harsher than others but SPS causes muscles to lock up, painful spasms, difficulty walking, slurred speech and/or double vision. It can be triggered by sudden noises, unexpected touches, cold, and emotional distress. Dion shared her journey in a raw documentary on Prime Video titled "I Am: Céline Dion." There’s no cure for Stiff Person Syndrome but the symptoms can be treated. Dion first returned to performing at the Paris Olympics opening ceremonies in 2024, which Rolling Stone deemed the 2nd greatest Olympics opening performance of all time
Rare diseases can be especially challenging for doctors to identify because their symptoms appear unrelated to one another (“clinically heterogeneous”) and, like other highly misdiagnosed conditions, the list of symptoms may be common to many other diseases. As discussed in Chapter 12: Why We Should Embrace Uncertainty in Medicine, the same elements that cause medical uncertainty operate on steroids when a patient has a rare disease. Rare diseases often progress in unfamiliar and bewildering ways. Patients may be viewed with suspicion, dismissed, ignored or refused any services.
Doctors were traditionally trained to avoid looking for them. Dr Theodore Woodward, a renowned physician in the 1940’s, taught medical school students, “When you hear hoofbeats, think of horses, not zebras.” His point was that most patients have common health issues and doctors shouldn’t waste their valuable time searching for exotic, uncommon ones.
In defiance of that attitude, many rare disease advocates and organizations have adopted the zebra and its stripes as the symbol for rare disease and rare disease patients. As the National Organization for Rare Disorders (NORD) states on their website, “Now, we know that one in ten Americans is actually a zebra! It might not be obvious when you look at us, which is why we show our stripes to raise awareness.”
Jameela Jamil turned her acting and modeling career into disability advocacy for others with rare and chronic disease. She was just 9-years-old when she was diagnosed with Ehlers-Danlos Syndrome (EDS). There are 13 types and Jamil has the more common hypermobile type (hEDS) which means her joints can bend in ways our bodies weren’t designed to do. If that were all, it might benefit dancers and athletes. But hEDS is a connective tissue disease whose symptoms include joint instability, chronic pain, and abnormal scarring. Jamil said in a podcast, “I'd been constantly dislocating. Since I was a baby, my shoulders would just slip out of their sockets at the age of about two, and then my legs wouldn't work properly…and no one knew what it was.” She said getting diagnosed so young, “probably saved the rest of my life.” Had she participated in contact sports at school, she added, she might have “died of internal bleeding or my bones would've broken or I would've dislocated my neck…” She says she got involved in disability advocacy early in her career because of the isolation and bias she experienced growing up, founding the I Weigh community in 2018.
Resources For Rare Disease Patients (Diagnosed Or Not)
There are several major nonprofit or federal organizations focused on researching, studying, diagnosing and treating rare diseases. Only the Undiagnosed Diseases Network (UDN) below is solely focused on diagnosis.
National Organization for Rare Disorders (NORD) was the first national nonprofit to represent everyone impacted by rare disease. They offer patient care, from diagnostic support, to access to specialists, and clinical trials. They provide research grants, conduct studies, patient registries, and partner with over 340 rare disease groups. They advocate for policies and programs that serve PLWRD. There are 39 rare disease centers of excellence listed on the NORD website https://rarediseases.org/rare-disease-centers-of-excellence/
The Genetic and Rare Diseases (GARD) Information Center is a federal agency under the National Institutes of Health (NIH) that provides free access to accurate and helpful information about rare diseases. Like NORD, they offer a large easy-to-search rare disease data base. They offer an array of resources including financial aid, help finding doctors and hospitals, transportation support, tips for dealing with health insurance and guides to talking with your doctor. GARD also has staff on-call by phone and email to answer your questions or help direct you to support.
The Undiagnosed Diseases Network (UDN) is a research study funded by the National Institutes of Health (NIH) It gathers clinical and research experts from across the United States to solve medical mysteries –– both rare and unrecognized conditions –– using every scientific tool available. It’s comprised of three functions: Data Management Coordinating Center, Clinical Sites, and Core Facilities. There are currently 24 clinical sites across the US where patients can be evaluated. Because one of the main coordinating centers is at Harvard University Medical School, the UDN became a political football lately when the federal government’s new tough stance towards Harvard University resulted in a cut of $7 million of the total $18 million budget. While they’ve acknowledged that the canceled funds affect their work, no one knows the long-term impact.
Every Life Foundation is a nonprofit, nonpartisan advocacy group fighting for policies and legislation to advance development of –– and access to –– better diagnostic approaches, treatments and cures.
Global Genes is a nonprofit that primarily supports other rare disease advocacy groups. But their Quick Guides also offer helpful advice for individuals, including how to deal with physician denial and gaslighting, knowing your rare child’s rights, even how to start your own nonprofit.
RareShare describes itself as an online social hub and aggregator of information about rare disorders.
How To Know If You Or Your Child Have A Rare Disorder?
Newborns: For decades, advocacy groups have worked to add newborn screenings for a growing list of rare and life-threatening conditions. Currently, newborns are automatically tested for at least 32 of them. Unfortunately, it’s not enough and it’s still a state-by-state decision. There are 38 conditions included on the federal Recommended Uniform Screening Panel (RUSP) but more can be done. Only 13 states on this map get a grade of A from NORD’s State Report Card.
Adults and older children: If you believe your doctor has missed a rare condition, return to these earlier chapters for step-by-step advice on navigating the serpentine diagnostic pathway that is US healthcare today.
Chapter 3: I Just Want To Feel Better
Chapter 7: Top Five Things To Do Before You See Your Doctor
Chapter 8: Specialists Have Blind Spots
Chapter 9: Medical Testing Secrets
Chapter 10: Gaslighted, Dismissed Or Ignored By Your Doctor?
Chapter 11: Get A Second Opinion. Get A Second Opinion. Get A Second Opinion.
Next Up: Chapter 16 - Throw Away The Pain Scale. A New Way To Communicate Pain and Be Heard.
© Helene M. Epstein 2025
[1] Idiopathic = unknown cause
Thanks for highlighting these struggles that so many go through, but so few understand. It's amazing to me that we continue to put up with a profit-driven healthcare system that serves mostly a handful of healthcare companies.
Thankfully new treatments are being developed. Getting the diagnosis is the problem!