Immunoglobulin Replacement Therapy

Immunoglobulin replacement therapy is a long‑term treatment for people with antibody deficiency, where the immune system cannot produce enough protective IgG antibodies. Low antibody levels increase the risk of recurrent or severe infections. Replacing these antibodies helps reduce infections and supports a more stable, active quality of life.

Immunoglobulin is a purified plasma‑derived product containing antibodies from carefully screened donors. Although it does not resemble a blood transfusion, it is made from human plasma and therefore follows strict international safety standards.

Why immunoglobulin replacement therapy Is Recommended 

For patients with significant antibody deficiency, immunoglobulin therapy can:

• reduce the frequency and severity of infections
• prevent long‑term complications such as bronchiectasis
• improve day‑to‑day energy levels
• support a more predictable, active lifestyle

Most patients experience meaningful improvements once their IgG levels are stabilised.

How Immunoglobulin Is Made Safe

Modern immunoglobulin products undergo several layers of safety controls:

1. Donor and plasma screening

Every donation is tested for:

• HIV
• Hepatitis B
• Hepatitis C

2. Virus‑inactivation and removal steps

Manufacturers use validated processes such as:

• solvent–detergent treatment
• low‑pH incubation
• nanofiltration

These steps significantly reduce the risk of known and emerging viruses.

3. Historical context

Past hepatitis C transmission occurred before reliable screening and virus‑inactivation methods existed. Current licensed products are not known to transmit HIV, hepatitis B or hepatitis C.

4. Variant CJD

Transmission of vCJD through immunoglobulin remains theoretical only. Current evidence suggests the risk is extremely low, although it cannot be completely excluded until validated screening tests become available.

Monitoring During Treatment

Before starting therapy, patients have baseline blood tests, including liver function tests (LFTs). These are repeated regularly to ensure continued safety. If liver enzymes rise unexpectedly, further investigation is arranged. Viral complications are rare with modern products.

Ongoing Care and Support

Immunoglobulin therapy is usually lifelong. Regular monitoring ensures the dose remains effective and well‑tolerated.

Specialist clinics provide structured follow‑up, review infection patterns, and adjust treatment as needed to maintain long‑term health and quality of life.

REFERENCES

• BSACI Guideline for Primary Immunodeficiency https://www.bsaci.org/guidelines
• ESID Diagnostic Criteria for Antibody Deficiency https://esid.org/Working-Parties/Registry/Diagnosis-criteria
• UKHSA Green Book – Immunoglobulin Use and Blood Safety https://www.gov.uk/government/collections/immunisation-against-infectious-disease-the-green-book
• EMA – Plasma‑Derived Medicinal Products Safety Measures https://www.ema.europa.eu/en/human-regulatory/overview/blood-products
• WHO Guidelines on Viral Inactivation in Plasma‑Derived Products https://www.who.int/publications