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5 things to know for Primary Immunodeficiency Month – Bio.News

April is Primary Immunodeficiency Month, and in observation, Bio.News is partnering with the Immune Deficiency Foundation (IDF) to talk about the condition and what you can do to better understand it.

But first, what is primary immunodeficiency (PI)? 

The name hints at the condition’s meaning; as IDF explains, “PIs are a group of more than 450 rare, chronic conditions where a part of the body’s immune system is missing or does not function correctly.”

While each of these immunodeficiencies is different and unique, they all have one common element: They disrupt the body’s immune system. PIs are also known as inborn errors of immunity (IEI). 

PIs have proven to be somewhat lesser-known conditions affecting the immune system. So, what are the top five things you need to know about PIs to keep yourself and your family safe?

1. People can wait decades before a diagnosis.

Most patients are diagnosed with a PI at 9-15 years from symptom onset. As a result, experts estimate that over 70% of individuals with a PI remain undiagnosed, explains IDF. While some PIs can be detected via newborn screening (for example, Severe Combined Immunodeficiency, or SCID, which can be life-threatening), most patients end up waiting much longer for answers.

The reason for this is that PIs are as complex as they are sneaky. “Because those with PI can have a variety of symptoms that are not specific to one organ,” writes IDF, “they tend to see multiple specialists while seeking a diagnosis.” 

In fact, some patients are not diagnosed until they are in their 60s, even though they’ve been sick their entire lives. That is why it is important to know some of the basic signs of PI.

If you are a doctor or patient, ask:

  • Infections that are frequent, persistent, unusual, and/or difficult to treat? 
  • Unusual complications of common infections? 
  • Unusual autoimmunity? 
  • Enlarged lymph nodes that persist and/or hepatosplenomegaly? 
  • Failure to thrive (including adults)? 
  • Non-healing skin ulcers? 
  • Recurrent fevers with no source?

2. The most common type of PI is common variable immune deficiency (CVID).

Even if you might not have heard of PI, you probably know a few people who have been diagnosed. For example, the musician Ke$ha was diagnosed with CVID in 2022 when she sought medical care after experiencing severe daily bouts of fatigue. While she, at first, blamed it on her rock star schedule, it soon became clear something else was going on.

“I had a really hard time saying no to interviews or photo shoots because I didn’t want to let my one chance fall away by not being able to fulfill every request,” Ke$ha told Self in 2023. “It led to severe exhaustion physically and mentally.”

But, as Ke$ha revealed, “I almost died in January,” after she underwent surgery to freeze her eggs and ended up in the hospital shortly thereafter. It took her two months to recover. 

Her story is a stark example of the dangers of PIs like CVID. And as IDF explains, CVID is “found in about 1 in 25,000 persons.” CVID occurs when there is a deficiency of serum immunoglobulins (also known as antibodies), which “are proteins that your immune system makes to fight germs, such as viruses and bacteria.” 

Though, as with many PIs, the variations of CVID are complex. So if you are noticing some of the symptoms of PI in your own life, talk to your doctor to get some answers.


If you want an enjoyable primer to CVID, the film “The Big Sick” chronicles the journey of Emily Gordon and her now-husband, Kumail Nanjiani, as he grapples with Gordon’s surprise hospital visit, diagnosis, and near death. While dealing with a serious subject matter, the movie is charming, enjoyable, and genuine. 

3. It is estimated that 6M people worldwide have a PI, but they may not know it.

“Around the world, over 6 million people are affected by primary immunodeficiencies, among which 70 to 90% remain undiagnosed,” states a 2021 PubMed paper.

In fact, as research increases, it is becoming clear that PIs are probably much more common than previously thought—and the numbers of those diagnosed with PIs are undoubtedly lower than reality. To put those numbers into perspective, only 27,000-60,000 patients have been diagnosed with PI within the projected 6 million person patient population.

As one study found, “For Europe, our upper estimate was 638,000 cases, and 15,052 cases are currently registered (2.27 %). In Africa, up to 902,631 people may have a PID, whereas only 1,016 cases are currently registered. We also found that PIDs were prevalent not only in children, but also in adults, who were strongly underrepresented in registries.”

But why are PIs so difficult to diagnose? Well…

4. People with PI may not look sick.

PIs are oftentimes an invisible illness resulting in less observable symptoms like fatigue or even the onset of low-level, yet manageable, infections (like ear infections) that just don’t seem to fully subside. Especially in women, such symptoms are often overlooked both in society and at the doctor’s office until a serious infection.

Additionally, no PI is made the same. They range in severity and onset, even being affected by a person’s stress level or lifestyle. Luckily, there are three main ways you can check for a PI if you are concerned:

5. Many with a PI are diagnosed with an autoimmune condition first.

Seeing as PIs are immune disorders, it is not surprising that false diagnoses of autoimmune conditions can get in the way of a proper diagnosis. But the distinction is key because these are two profoundly different conditions.

While PIs are a result of having an “immune system [that] fails to respond adequately to infection,” autoimmune disorders are a result of an “opposite condition, [where patients have] an overactive immune system that attacks healthy cells as though they were foreign bodies.” 

The treatment of a PI with immunosuppressive drugs often used for autoimmune diseases can be incredibly dangerous, so if you want to be extra sure of your diagnosis, ask your doctor to test you for PI. This is especially important to do if you know you have a family member with PI, as the condition often runs in families and can be genetically linked. 

You have the power.

Though PIs can be a scary diagnosis, the power is still ultimately in your hands as a patient, especially with the ever-increasing amount of information and research on the condition. If you are concerned, talk to your doctor. You can also get more information on PIs at the Immunodeficiency Foundation’s website: