Some Types of PI:

Selective IgM Deficiency (SIGMD)

Patients with SIGMD have low levels of immunoglobulin M (IgM) with normal IgG, IgA, and T cells (a type of immune cell). SIGMD is diagnosed in both children and adults and is one of more than 400 different types of primary immunodeficiency (PI). Some patients may have no symptoms, but about 80% of patients have infections caused by a variety of microorganisms. Even among immunodeficiency diseases, SIGMD is uncommon. The exact cause of SIGMD is unclear, but several chromosomes are known to have gene defects that may cause SIGMD.

There are over 450 different types of PI, each with its own characteristics and challenges.
Need a crash course? Learn the basics of PI.

Symptoms of selective IgM deficiency (SIGMD)

Similar to other PI disorders, individuals with SIGMD have frequent infections caused by bacteria, fungi, and protozoa. The frequent infections happen because, without healthy IgM or working/functional IgM, the person is not able to develop strong IgG responses. Adults also often have autoimmune disorders, and about 40% have allergies. Autoimmune disorders are more common in adults than in children.

Diagnosis of selective IgM deficiency (SIGMD)

Since the symptoms of SIGMD are similar to other antibody deficiencies like CVID, to confirm a diagnosis for SIGMD, doctors look for low levels of healthy IgM, along with a normal number of T cells.

What should I know about treatment for selective IgM deficiency (SIGMD)?

You are not alone, but no one is quite like you. It's important to learn about the various treatments for PI, and should be individualized to meet your specific needs. Your healthcare team is there to provide recommendations based on you, and your situation. Here are some tips:

Keep track of how you’re doing and share the information with your doctor on a regular basis.
Your doctor will only know how you’re doing if you tell them. If you have questions, concerns, thoughts or feelings—speak up and share!
You and your doctor both play a part in managing your health. You can take an active role by learning as much as you can and by following your doctor’s recommendations.