With appropriate access to the different and very effective therapies which can only happen if the early and correct diagnosis is made, many sequelae will be avoided and the lives of patients will be saved.
People with PIDs are typically treated by doctors who specialise in diseases of the immune system. How a patient is treated depends on which PID they have, and on many other factors. Mainstay or curative treatments for PIDs include immunoglobulin (IG) replacement therapies, Hematopoietic Stem Cell Transplantation (HSCT, also known as ‘bone marrow transplantation’), gene therapy, cytokines such as Granulocyte-colony stimulating factor (G-CSF), recombinant gamma interferon, enzyme replacement therapy such as recombinant adenosine deaminase for patients with ADA1 deficiency, anti-infectious prophylaxis (with antibiotics, antifungals and/or antivirals), monoclonal antibodies, among others.
Immunoglobulin replacement therapy
In the case of IG replacement therapies, it is important to know that different IG products are not interchangeable or mixable. IG can be administered intravenously or subcutaneously. They are considered essential medicines for PIDs by the World Health Organisation. Intravenous immunoglobulin (IVIG) infusion usually takes 2-4 hours allowing high doses to be given and only needs to be given every 3-4 weeks which may suit some patients better.
Subcutaneous immunoglobulin (SCIG) can only be given in small doses. It only takes 1-2 hours and can often be given at home by patients themselves, parents or carers. This option may therefore be more convenient for some patients. SC infusion preceded by an SC infusion of recombinant human hyaluronidase, which is known as ‘facilitated’ subcutaneous immunoglobulin (fSCIG) allows patients to have SC infusions every 3-4 weeks. IG therapy should be discussed on a shared-decision basis for each individualised case, according to patient needs and preferences.