Autoimmune Neutropenia

What is autoimmune neutropenia (AIN)?

Autoimmune neutropenia (AIN) (pronounced “noo-troh-PEE-nee-uh”) is a blood disorder that involves your immune system attacking your body’s neutrophils (a type of white blood cell). Neutrophils are an essential part of your immune system. They destroy harmful bodily invaders that cause infections, like fungi and bacteria. With autoimmune neutropenia, your immune system mistakenly attacks these white blood cells. As a result, you have a lower-than-normal level of neutrophils in your blood.

AIN may be primary or secondary.

• Primary autoimmune neutropenia primarily affects infants and toddlers. It involves having a low neutrophil count that can’t be explained by other causes. Primary neutropenia usually resolves on its own within a few years.
• Secondary autoimmune neutropenia is more common in older children and adults. It involves having a low neutrophil count resulting from another condition, including infections, blood disorders, etc. Other autoimmune diseases often cause neutropenia. An autoimmune disease involves your immune system mistakenly attacking your body instead of protecting it. Secondary autoimmune neutropenia is usually chronic (long-lasting).

How low do your neutrophils have to be to be considered neutropenia?

Autoimmune neutropenia is just one type of neutropenia. Neutropenia is classified as mild, moderate or severe depending on how many neutrophils are in a microliter (microL) of blood.

• Mild neutropenia: 1,000 – 1,500 microL.
• Moderate neutropenia: 500 – 1,000 microL.
• Severe neutropenia: Less than 500 microL.

How does autoimmune neutropenia affect my body?

Your experience of AIN depends on multiple factors that you should discuss with your healthcare provider. Having too few neutrophils can put you at risk of getting infections. These infections may even be life-threatening without emergency medical attention. In other cases, autoimmune neutropenia may cause mild infections or no symptoms (asymptomatic).

Work with your healthcare provider to determine what’s causing your neutropenia. Based on the causes, your provider can monitor your condition to keep infections under control.

Who does autoimmune neutropenia (AIN) affect?

Primary autoimmune neutropenia mainly affects infants and young children. On average, it’s diagnosed around eight months old. Secondary autoimmune neutropenia is often due to another autoimmune disease, like lupus or rheumatoid arthritis. Most children with secondary AIN are diagnosed around age 10 (on average). Most adults diagnosed with secondary AIN are between the ages of 40 and 60.

How common is autoimmune neutropenia?