I Thought I Just Got Sicker Than Other People—Until a Blood Test Led to a Life-Changing Diagnosis

I never suspected I might have an immune deficiency disease.
I Was Born With a Weakened Immune System
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In 2001, Megan Ryan, 46, was diagnosed with common variable immunodeficiency (CVID), one of the most common types of primary immunodeficiency diseases, or PIDDs, which are rare genetic disorders that impact a person’s ability to fight infections. PIDDs can cause a wide range of symptoms, in part because there are so many types: roughly 500 that scientists are aware of to date, and new disorders are discovered each year. Here, she shares how her condition impacts her life, as told to health writer Korin Miller.

I was 24 years old and fresh out of college when I saw a doctor for random pains in my legs. They ran a series of tests, during which they found an unrelated issue: My blood proteins were abnormal, so they referred me to an immunologist. I wasn’t thinking much would come of it when I made the appointment. Those pains ended up being harmless and going away on their own, but accidentally discovering the issues with my blood proteins along the way led me to receive a diagnosis that changed my life.

The immunologist told me I have common variable immunodeficiency, a type of primary immune deficiency disease that causes low levels of antibodies in the blood. CVID is relatively rare: Roughly one in every 25,000 people develops it, and researchers aren’t entirely sure what causes it. (My leg pain turned out to have nothing to do with CVID.) I learned that having this condition meant I was more likely to have bacterial and viral infections in my sinuses, upper airways, and lungs, along with digestive issues like diarrhea and liver problems, among a host of other potential complications. I was no stranger to frequent, unexplained illnesses: As a kid, I had a long episode of chickenpox and cat scratch disease. In college, I seemed to contract every bug that went around, which led to issues like pink eye and sinus infections. I just assumed I was someone who was constantly sick—not that my immune system had to work harder than most people’s.

After receiving my diagnosis, my doctor recommended that I start immunoglobulin treatment, during which a health care provider injects human plasma from donors to boost a person’s immunoglobulin levels (the antibodies primarily responsible for defending your immune system against infections). I got IV infusions that sometimes lasted the entire day. Luckily, my job allowed me to work remotely while I received treatment—and that was important: I needed health insurance through my employer to help me pay for all these expensive procedures. 

Around that time, I developed a rare gastrointestinal condition called malakoplakia of the colon,1 which gave me chronic diarrhea that took more than a year to get under control. It was one of the most challenging times in my life—I lost a ton of weight, was constantly fatigued, and made frequent trips to the bathroom. I eventually recovered with antibiotics, but the illness was a brutal reminder to do my best to avoid getting sick in the first place. I started using curbside pickup at the grocery store, wearing masks during flu outbreaks, and going to outdoor concerts with good airflow instead of indoor shows. I told loved ones to keep their distance if they were sick, too: If a friend’s child had a cold or the flu, we didn’t get together. When my husband gets sick, I take extra precautions: One of us sleeps in a different bedroom, and I sanitize the sheets on my bed, wipe down the counters, and do lots of handwashing. Sometimes bleach is my best friend. 

I love to travel, but flying is always a risk for me. Around the time when masks became optional on airplanes following the height of the pandemic, I had an opportunity to travel across the country for work. I opted to stay masked throughout the journey. Plus, I chose a flight I knew would be less crowded and brought plenty of sanitizing wipes. That planning helped me feel comfortable on my trip—and I was able to have a new professional experience! 

Despite my best efforts, I still get sick—and I often need to receive treatment differently than most other people when I do. I get a lot of bacterial infections, and each time, I need a longer course of antibiotics than I would if I didn’t have CVID. I’ve also learned to educate my health care providers about my needs. If I need to go to an urgent care center or see a new doctor online, I tell them about my condition and how it’s commonly treated so that we can work together to find a tailored solution.

While I still do regular infusions, they’re now once a week, and I give them to myself via an infusion pump. This allows me to receive treatment on my own schedule in the comfort of my own space—I can sit at my desk and work or watch a movie while it’s happening. At-home infusions help me feel more in control, which is important when I live with a condition that’s largely out of my control. And I’m living a full life, even with this diagnosis. I can do the things that are important to me, and that’s what matters. 



  1. World Journal of Gastroenterology, Malakoplakia of the Colon Associated With Colonic Adenocarcinoma Diagnosed in Colonic Biopsies