PIDD: A Patient’s Perspective

PRIMARY IMMUNODEFICIENCY disease (PIDD) is an umbrella term encompassing nearly 200 genetic disorders that feature an absent or diminished immune system. PIDD affects as many as 500,000 Americans and 10 million people worldwide, but is often difficult to diagnose. One of the reasons is explained in a theme adopted by the Immune Deficiency Foundation: “Think zebra.” The term derives from a medical school adage: “When you hear hoofbeats, you see horses, not zebras,” which encourages physicians to look for the likeliest possibilities when making a diagnosis. PIDD patients are considered “zebras” in the medical world.

While many PIDD symptoms present themselves in early childhood, on average, it takes between nine and 12 years from the beginning of symptoms to make a diagnosis. This was certainly the case with the Darr family.

Misdiagnosis: It Must Be Day Care

Dona Darr’s world changed for the better in 2003, when her daughter Emily was born. A healthy, happy baby, Emily was a blessing from the start. When her daughter was 18 months old, Dona made the emotionally difficult decision to enroll Emily in day care. An outgoing child, Emily made “fwends” quickly, and Dona was relieved things were going so well. Then Emily got the first of seven recurrent ear infections, and Dona panicked. “Her pediatrician said it was normal for a child in day care to be sick a lot, but seven infections in four months seemed excessive,” says Dona. “I knew something wasn’t right.”

On the advice of friends, Dona took Emily to an ear, nose and throat specialist. After she provided the physician with her daughter’s medical history, the doctor looked her in the eye and asked if Emily had been tested for immune deficiency. “I was stunned,” says Dona. “The following month, we went back to the pediatrician for blood work, and I felt like the most horrible mother as I held her little body down while they drew blood. Little did I know that this procedure would become a common occurrence throughout her life.”

Two weeks later, the results came in. It was confirmed that Emily’s IgG levels were low, making her more susceptible to infections and in danger of serious complications if she contracted influenza or pneumonia. The treatment plan? “Just call if she gets sick, and treat viral infections as soon as possible.”

The Eight-Year Journey

The next two years were filled with doctor appointments and trips to the ER. One misdiagnosis landed Emily in the hospital with pneumonia. When it happened a second time, Dona decided to change doctors. During a consultation with her new pediatrician, Dona heard the term “immunologist” for the first time, but based on Emily’s blood work, she was unable to get a referral. Countless strep and viral infections later, Dona began researching her daughter’s symptoms on the Internet, and what she learned astounded her. There were thousands of other patients with symptoms just like Emily’s; she was not alone, and it was time to see an immunologist. “If no doctor would refer us, I decided I would refer us myself,” she says. “Eight years from the start of our journey, my now 10-year-old daughter was close to a diagnosis. We found an immunologist who started looking for the ‘zebra,’ instead of the horse.”

Emily’s diagnosis was IgG subclass deficiency with specific antibody deficiency. Her treatment plan includes prophylactic antibiotic along with yearly pneumovax and meningococcal vaccines, with monitoring and testing every three months. If breakthrough infections occur, her immunologist may consider intravenous immune globulin therapy, a common treatment and effective for PIDD.

“Emily’s life is forever changed and may include a future filled with doctors, hospitals, medications and labs,” says Dona. “But she is strong and resilient. I am so glad I never strayed from that gut feeling and that I kept fighting to get her help.”