Version July 2025
INTRODUCTION —
This topic was written by an individual patient diagnosed with erythropoietic protoporphyria (EPP). It is intended to offer clinicians insight into the experience of a single individual from that individual's point of view, which may enhance clinical practice and health care delivery. This description of a particular patient's experience is not intended to be comprehensive or to provide recommendations regarding diagnosis, treatment, and/or medication information. It is not intended to be medical advice or to be a substitute for the medical advice, diagnosis, or treatment of a health care provider based on the health care provider's examination and assessment of a patient's specific and unique circumstances.
For related clinical topics, please see:
●(See "Erythropoietic protoporphyria and X-linked protoporphyria".)
●(See "Porphyrias: Overview of classification and evaluation".)
UpToDate also offers patient education materials. "The Basics" topics are short overviews written in plain language, at the 5th to 6th grade reading level, that answer the main questions a patient is likely to have about their condition. You can share this content directly with your patients:
●(See "Patient education: Erythropoietic protoporphyria and X-linked protoporphyria (The Basics)".)
●(See "Patient education: Porphyrias (The Basics)".)
EARLY CHILDHOOD
Initial symptoms — As a kid, my family called it the "sun thing." This referred to the bizarre reactions my brother and I would experience after being in the sun for too long.
The "sun thing" meant many days of being inside with severe pain, ice, cold water, fans, and almost no sleep. For as long as I can remember, age 2 to 3 according to my mother, too much sun exposure would lead to itching and tingling of my hands, face, and feet, then excruciating, burning skin pain that lasted about a week.
I was born in Oklahoma, but I moved to Macau, China at the age of 2 years. Though it was a blazingly hot and sunny tropical climate, it was a rather good place to have a "sun thing." People in Asia commonly wear all kinds of sun-protective clothing, so I could walk around with umbrellas if needed. Still, I would have the sun reactions sometimes, especially in the summer.
Early on, no changes showed up in the appearance of our skin. It wasn't until around age 7 to 8 that my brother and I both started to get massive swelling of the hands and face with these reactions, but still, no redness as would be expected in a normal sunburn.
While the pain wasn't any different from before, the visible effects changed over time. Even so, what you could see on the skin was never anything compared with the pain.
Attempts to get a diagnosis — Doctors could see the swelling of my hands and face, but they could not identify the cause.
●The dermatologist my brother and I saw when we were little told my parents to take us home and spank us. We were making it up, he said.
●Other doctors thought maybe my brother and I had an allergy to sunscreen, so we tried different types of sunscreens or no sunscreen at all, but this did not make any difference. Sunscreen didn't help or hurt. Could it really be a "sun thing" if sunscreen didn't help?
●We had also tried acetaminophen, ibuprofen, aloe, steroids, diphenhydramine, and every cream you could find. Nothing helped.
Physical and emotional pain — The burning pain of "the sun thing" was all-consuming. Once symptoms started, any sun exposure felt like a burning laser was incinerating my skin. It's not the sort of pain you can push through, maybe for a little bit, but it always wins.
It feels like:
●A fly being tortured to death by a magnifying glass and the sun.
●Being thrown into a flame with an irresistible reflex to jump out to survive.
•Even after going inside, the flame is still there – for days.
•It's hard to keep my hands still because of the flame, as if flinging my hands against the flame might help put it out, but it never does.
The pain lasts about a week. It demands attention, impossible to think or sleep or do anything else but just sit in a dark room and wait for it to go away. The harder I pushed my light exposure, the worse it knocked me down.
I was not a kid known to be melodramatic about pain. In the 1st grade, I had tubes surgically placed in my ears, staying still without any anesthesia and without any crying. I had been so tough during other things that the doctor seemed to think anesthesia unnecessary. But the "sun thing" would make me cry every time. It still does.
My parents sent me to summer camp when I was young, thinking it would be fine. It never was.
●I remember a camp counselor telling me to stand under a twig of a tree as I tried desperately not to lose it in front of my friends.
●Every year, not long after the camp started, I would be sitting on a bunk by myself, crying with my hands in a bowl of water. I had no diagnosis, and visible symptoms weren't always present.
●My friends and the camp counselors didn't understand, and I couldn't explain it. I didn't understand either.
●I didn't understand why other people could do things that I could not, no matter how hard I tried.
My family moved back to the United States before my 7th-grade year. We went on a family vacation to Washington, DC, and I was already starting to have the beginning tingling and itching symptoms due to the light exposure in the prior days. I could not convince my parents to let me stay back from sightseeing, though. They didn't want me to "miss out." My skin looked normal. Did I need to be so dramatic?
In middle school, on that family vacation, I tried so hard to push through, but the pain eventually won. I broke down in tears and frustration in front of the Lincoln Memorial. My skin looked 100 percent normal. I'm sure any onlooking fellow vacationers thought some middle school kid was having a temper tantrum at a far older age than socially acceptable. I couldn't take it anymore.
For the next few days, I stayed in a dark room with ice and an air conditioner and didn't sleep. My hands swelled to twice their normal size, and this time I developed petechiae and scabbing over my hands.
Finally, an answer — After the trip to Washington, DC that left me in a hotel room with severe swelling and pain, my parents decided they needed to find an answer.
We initially went from doctor to doctor, clinic to clinic, but no answer was forthcoming. Then the pediatric dermatologist, who also did not know what my diagnosis was, suggested I be presented as a mystery case at a local dermatology conference.
Doctor after doctor heard my story and looked at my hands. They proposed a possible diagnosis: erythropoietic protoporphyria (EPP). Soon after, I saw a hematologist who was a porphyria expert and scientist. My metal-free erythrocyte protoporphyrin level was 2600 mcg/dL; normal is <20 mcg/dL.
The diagnosis was confirmed. I had EPP.
LIVING WITH EPP
EPP explained — Erythropoietic protoporphyria, or EPP, is one of a family of eight different conditions affecting eight different enzymes of heme synthesis. These eight enzymes change succinyl CoA and glycine into heme.
The biochemical intermediates that accumulate in each type are responsible for the symptoms of porphyria. The eight conditions are distinct, with symptoms that are sometimes overlapping with other types.
While EPP is essentially identical to X-linked protoporphyria (XLP), it shares almost no clinical features with the other types of porphyria.
●In EPP and XLP, metal-free erythrocyte protoporphyrin accumulates, especially in the red cells but also in the plasma and bile. Protoporphyrin is heme without the iron in the middle, and it is a particularly light-sensitive molecule, with a structure similar to chlorophyll.
●Activation by light causes internal damage, especially at the level of the endothelium, and, most prominently to the patient, severe pain.
●While the light sensitivity of EPP is not fatal, protoporphyrin can damage the liver, causing liver failure, which may be fatal.
EPP is recessive, but it shows up more frequently in families than many other recession conditions. The reason is that more than 95 percent of patients typically have only one rare pathogenic variant in the gene that encodes ferrochelatase (FECH) in combination with a common low-expression allele that is present in 10 percent of White individuals.
Told to remain silent — Although the doctor told me all these things about my condition at diagnosis, there wasn't any cure for EPP. The only treatment was high-dose beta carotene, and that just turned my skin orange. It didn't help. Even still, the diagnosis was incredibly validating. I wasn't crazy.
The doctor who diagnosed me suggested that my brother and I not tell others, "because you never know what prejudices people may have." So, although I had a name for my symptoms, I did not tell people my diagnosis.
I remember being very insecure about having EPP. I declined invitations and disappeared from events without good excuses. I made sure to pick jobs and activities that allowed me to get out of the sun immediately whenever needed.
I went on to become a doctor and a critical care specialist with an interest in porphyrias. Although EPP was part of what drew me to medicine and research, in medical school, I became even more uncomfortable with sharing about my condition. I learned that doctors weren't allowed to need normal human things like food, sleep, or bathroom breaks, much less have a medical problem of their own.
A medical school friend once told me about how much he liked the television show House. He said, "You know, there was even an episode about a girl who was allergic to the sun?!" I had heard there was an episode about EPP, and, not being able to resist such a comment, I responded, "Yes, I have that." This was followed by an extended exchange of "No, you don't," "Yes, I do," broken only by my explanation of what EPP is and my symptoms.
Finally opening up — In medical school and residency, people talked about testing for porphyria as if it were a test for a Martian gene: nobody really had it, and testing for it was a waste of time and money. "Some people really do have porphyria," I would say. I realized that if I continued to be secretive about my diagnosis, it would be my own friends who would miss a case of porphyria. These misdiagnoses and delays in diagnosis could be my fault.
During fellowship, I started to be more open about my diagnosis. Surprisingly, my experience telling people about my condition was universally positive and therapeutic.
Meeting other EPP patients was especially meaningful. I went to an EPP support group meeting and found an EPP Facebook group. So many people had experienced the same things as me! I was not alone. There was a whole group of people who understood something very formative about my life experience that nobody else understood. They all seemed like long-lost family.
Medical career — I specialized in internal medicine and pulmonary/critical care. But I was drawn to studying porphyria, and I eventually co-founded the Porphyria Center at Mass General Hospital.
My first EPP-related research project satisfied my own curiosity about others' experiences with telling people about EPP. I asked patients if they told others about their EPP, who they told, and why. Many others were like me and didn't tell people. However, I found that those who were most open about sharing were most confident that their communication strategy was beneficial.
Another EPP project estimated EPP prevalence in a large genetic and clinical dataset, providing evidence for the underdiagnosis of EPP. This fits with my experience of a delay in diagnosis and that of many other patients I know.
Other projects include developing a wearable light dosimeter for patient self-monitoring and clinical trial endpoints, identifying genetic modifiers of EPP, and clinical trials of new medications for EPP.
I have now taken care of many EPP patients and have been an investigator for clinical trials of three different medications for EPP. When I was diagnosed, essentially no therapy existed for EPP, and I didn't have much hope for one. I've been thrilled to see new, effective therapies being developed for EPP.
Support from other patients — As a porphyria researcher and doctor, it's hard to describe how impactful it's been to meet so many other EPP patients and to do something to help my EPP family.
Through meeting many other patients, I've learned that my EPP is on the very mild side. I can be outside for about an hour if no recent light exposure. Many patients have symptoms almost immediately after going outside or have reactions even to bright indoor lights. Because we're sensitive to blue light and not ultraviolet (UV) light, sunscreen does not work, and, in some, indoor lights can cause symptoms.
There is much more to be done. One patient with liver failure from EPP recently received a liver transplant, and I've interacted with multiple others in similar situations. I've never had liver issues, but approximately 2 percent of EPP patients will either die of liver failure or get a transplant, with my age being rather typical for this to happen. EPP liver failure can progress suddenly and rapidly, and we do not have good ways to prevent, predict, or treat it. It's sometimes unsettling and overwhelming to see so much of myself in my patients, wishing I could do more to help my EPP family.
My brother is part of my EPP family too, and his degree of light sensitivity is even milder than mine. During the family vacation to Washington, DC in middle school, he was outside for the same time as me but did not experience any skin symptoms. I also have two third cousins with EPP and a great-great-uncle who likely had it. He was one of five brothers. The rest were farmers, but he went to college because he couldn't be in the sun. EPP was only first described in 1961, so at the time he was alive, diagnosis was impossible.
Gratitude and frustration — I'm grateful to the doctor who diagnosed me and grateful that she was able to put a name to my symptoms.
A couple of years ago, however, I was commenting on the reaction that led to my diagnosis in a conversation with her. "No, No, No! You didn't have a severe reaction! You just had some mild symptoms on the drive home. You didn't have any swelling! No, you didn't have petechiae!" She raised her voice, angry and completely unconvinced of what I was telling her. "You can read my medical note to see what happened!" she told me.
I did not need to read her medical note. I remembered – more than I wished I did. If her note said something different, it was wrong. I don't remember what my family said to her many years ago.
I was also an EPP expert myself at the time we had this conversation. Yet, she was still convinced she knew more than me about my own experience. Unsuccessful with anything I said, I walked away from the conversation.
I wish I could say she was the only doctor who has been convinced they knew more than me about my own experience. My experience with EPP is still sensitive and personal. That's why it sometimes seems easier not to tell people about it. But I'm convinced that the benefits of telling have greatly outweighed the risks.
ADVICE FOR OTHERS —
I've come away with some life lessons through my experiences with EPP.
Be patient — Invisible illnesses can lead to many misunderstandings between patients and doctors, between patients and their friends and family members, and even within patients themselves.
●Patients with rare diseases may not always understand their symptoms or what's going on with them and may not have the perfect words to describe it in the moment, especially as a kid and especially before diagnosis.
●Patients may have developed trauma responses that lead them to minimize, deny, overdramatize, or give incoherent explanations.
Please be patient with us. Just because the symptoms are unusual or do not make sense to you, that does not mean we are making them up or trying to be difficult. It doesn't mean you know more than we do about our own experiences.
As a doctor, I understand the urge to be defensive or dismiss patients.
●Sometimes patients are making it up, and it doesn't feel good to be on the other side of that.
●Sometimes, patients will unleash all their emotions about their disease on any nearby doctor, seeming to blame the doctor for all they've experienced, even at the first visit, before having a chance to do anything good or bad.
●Some patients can simultaneously have too high and too low expectations for doctors, assuming both that doctors don't have any limitations in our ability to fix medical problems and that any of their symptoms are a result of doctors' ill intentions.
We doctors don't have a crystal ball to understand everything about the past, present, or future or magic wands to make everything in the world right again. We can't fix everything, and we don't know everything.
Accept limitations — Patients have physical limitations, but doctors must be allowed to have limitations too, which can make both patients and doctors uncomfortable at times.
As a patient with a rare disease, dealing with limitations has been hard. As a doctor, I don't like limitations for myself. Medical problems are things that other people have.
But being a doctor doesn't change my humanity or physiology.
●I had to live with a difference in how hard I could push myself physically. In my professional career, pushing harder got me better results. But with EPP, the more I pushed myself to tolerate the sun, the more pain I would experience, with escalating symptoms that were so much worse in the end.
●We doctors are humans with limitations somewhere. Hunger, fatigue, medical problems, and other limitations aren't just things other people experience. Strong and unyielding physical limitations at a young age formed me, teaching me that I am human and a partaker in human suffering.
Especially in medical school, I tried to reject and push away the part of me that reminded me of my physical limitations, as if becoming a doctor would graduate me from humanity.
But it wouldn't go away. For all of us doctors, humanity and its illnesses are still part of us. Doctors don't know everything, can't fix every illness, and will get sick ourselves someday. Examining, naming, and coming to terms with the broken places in all of us, including things we don't know, will bring healing and make us better doctors and citizens of this world.
