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Answers to Commonly Asked Questions About Common Variable Immunodeficiency (CVID) Marc Riedl, MD, MS, board-certified in allergy/immunology and an associate professor of medicine in the division of rheumatology, allergy and immunology at the University of California, San Diego, was the guest expert at the IG Living Readers Teleconference held June 24, during which he answered many commonly asked questions concerning CVID.

Why Is CVID Referred to as “Common There has been a lot of effort to or granulomatous disease, physicians Variable” When It Is Not Common? raise awareness about PIs over the don’t equate that to an immune defi - The prevalence of CVID is about years. And, while awareness has ciency, and CVID gets overlooked. one in 25,000 people, which makes improved, CVID is still very rare. So, Finally, today, doctors specialize in CVID a rare medical condition. However, one reason it takes so long to diag - certain areas of medicine, and when looking at the genetic causes nose is because most physicians and through no fault of their own, they of primary immunodeficiency diseases healthcare practitioners are either not often don’t look at the big picture. As (PIs), CVID is one of the most preva - familiar with the disease, or they may such, individuals have to run into lent. Therefore, in the realm of PIs, have heard about it in their training, the right specialist or seek out the CVID is quite common. CVID is referred but have forgotten about it. Therefore, physician who will look at the big to as variable because of the symp - CVID is not something they’re think - picture of various symptoms and toms associated with it — infections, ing about or testing for. conduct the appropriate testing. gastrointestinal (GI) issues, lymphoma, Another reason CVID can take so Yet, even when physicians think of etc. — that vary from person to person . long to diagnose is that there is a CVID as a possible diagnosis, they As such, there are many different per ception that PIs are a pediatric often don’t know what tests to con - symptoms and different clinical courses problem — something that is diag - duct or how to interpret those tests. in people who have the same disorder. nosed at birth or early in life. So, many This is a particular challenge, so adults have to battle the myth that it physicians who are not familiar with Why Does CVID Take doesn’t happen to adults or that they CVID are being encouraged to refer So Long to Diagnose? would have already been diagnosed. patients to a practitioner who is famil - Historically, it has been a chal - In addition, finding the right doctor iar with the disease. Unfortunately, lenge to get the proper testing for to diagnose CVID can be a challenge. there is a relative shortage of specialists diagnosing CVID because it is a rare The symptoms of CVID can be similar who have a strong interest in this kind condition. According to the most to other common conditions: sinus of immunology. recent studies, diagnoses are being infections, bronchiectasis, bowel made earlier, but we have a long issues, etc. These are conditions that How Is the Time of CVID way to go to get CVID diagnosed a lot of physicians see as run-of-the- Diagnosis Calculated? quickly after the onset of symptoms mill; but they’re not, if they keep Studies that look at the time to in most patients. Older studies recurring. It takes a certain healthcare diagnose CVID base it on the date showed it took a decade or more to practitioner to know that recurring from when a patient first started to diagnose CVID. Today, on average, it infection is not normal. And, while record recurrent infections or pre - takes about five to seven years to infection is the hallmark of CVID, senting symptoms to when they were diagnose CVID; however, some there are also many other symptoms tested and diagnosed. This is an inexact patients still aren’t diagnosed for 10 and complications. For instance, if science, however, because it relies on to 20 years or more. the primary symptom is GI problems backward tracking and recollection.

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Does CVID Run in Families, and don’t like to diagnose children with In short, infectious problems can Is There Genetic Testing for It? CVID until they’re older than 5 years. be treated with IG; other conditions Even though it is believed CVID is In most patients, CVID is diagnosed can’t. Therefore, it’s important for caused by genetic mutations, only after puberty. CVID patients to have regular follow- about 10 percent of diagnoses are up with their physician to identify any clearly familial. Ninety percent are What Is the Risk of Serious Disease other conditions that may arise and sporadic, which means the disease with CVID, and What Can Be Done treat them early. shows up in only one person in the to Prevent It? family. Therefore, only a small minor - Historically, the major risk of CVID Can CVID Patients Have an ity of patients have inherited CVID. is overwhelming infection (bacteria in Autoimmune Disease but Test The problem with such testing, the bloodstream, meningitis, etc.). Negative for It? though, is that a genetic mutation The good news is that infections have One of the challenges in dealing can be identified in only about 15 dramatically been reduced in patients with CVID and its associated compli - percent of all CVID cases. In the other who are diagnosed and properly cations is that patients don’t make 85 percent, the genetic mutation is treated with immune globulin (IG). antibodies well. This includes autoan - unknown. Genetic testing is relatively And, these days, serious complica - tibodies, and because ADs are typi - expensive, so without a high rate of tions such as chronic lung disease cally diagnosed based on autoanti - success, it is often not clinically useful (which occurs in 25 percent to 30 body assays, CVID patients may have outside of the research setting. Much percent of patients) resulting from all the signs and symptoms of an AD, more research needs to be conducted bronchiectasis may be prevented or but their autoantibody lab tests may to understand the genetics related slowed with IG therapy. be normal. In addition, IG therapy to CVID. But, there are other conditions, like may interfere with the lab tests that granulomas and lymphoma, that look for autoimmunity, which can What Is the Difference aren’t likely related to infection and make them unreliable for CVID between Hypogammaglobulinemia cannot be prevented with IG treat - patients. Therefore, these patients and CVID? ment. There are also autoimmune need to find a rheumatologist who will Hypogammaglobulinemia is a diseases (ADs) associated with CVID, conduct a comprehensive physical nonspecific diagnosis. Basically, it ranging from low blood cell counts examination for an AD and recognize describes a laboratory value that and arthritis to lupus. Additionally, 20 that the lab tests won’t necessarily shows antibody levels are low, but percent of CVID patients also have test positive for it. gives no other information on the serious GI problems, ranging from condition. CVID, on the other hand, irritable bowel disease, Crohn’s dis - Are CVID Patients Treated with has specific criteria: low IgG plus ease, ulcerative colitis, malabsorp - Medications Other Than Immune low IgA and/or IgM levels. tion, giardia, etc. A final serious com - Globulin? Therefore, hypogammaglobulinemia plication occurs with the spleen and IG is the primary treatment for CVID. is a general diagnosis, whereas CVID lymph nodes. A third of CVID It is the only proven treatment for is a more specific diagnosis. patients will develop problems with pre venting infectious complications. It’s possible for children to have the spleen and lymph nodes, but However, there are a lot of other med - transient hypogammaglobulinemia, these problems are largely benign. ications that might be used to treat which means their IgG levels are low, Approximately 8 percent of the time, complications of CVID. These include but they become normal as they age. these problems can result in lym - antibiotics (although chronic prophy - This sometimes occurs in children phoma. Unfortunately, we don’t lactic antibiotics are not commonly under 5 years old because the devel - have any way to prevent any of these prescribed), immunosuppressant drugs opment of the immune system is conditions; we can only recognize to treat ADs, GI problems or lung delayed. Therefore, because it could them early and treat the symptoms problems, and chemotherapy to treat be transient, physicians generally as they arise. lymphoma, which rarely occurs.

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