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Health condition

Chronic granulomatous disease, a rare immune defect that is treatable and, increasingly, curable.

CGD is a lifelong condition where phagocytes cannot generate the oxidative burst needed to kill certain bacteria and fungi. UK care combines lifelong prophylaxis, aggressive infection control and, for many, curative stem cell transplant or gene therapy.

A radiographer guides a patient onto the bed of an advanced 3 Tesla MRI scanner in a London imaging suite

Why trust this guide

  • 01

    Editorial team

    Written by our editorial team from the UK sources listed on each page.

  • 02

    Sourced from guidance

    Checked against UK PID network standards, ESID and peer-reviewed sources you can see at the end.

  • 03

    Current for 2026

    Reflects modern UK practice including DHR flow cytometry, lifelong prophylaxis, HSCT and emerging gene therapy for X-linked CGD.

Key facts

CGD at a glance.

The essentials, in plain English: what CGD is, how it is inherited, how it is diagnosed and how it is treated in the UK today.

  • What it is

    A rare inherited primary immunodeficiency where phagocytes cannot generate reactive oxygen species, so they struggle to kill certain bacteria and fungi.

  • Genetics

    X-linked in about 65 per cent of cases (CYBB, gp91phox) affecting mostly males; autosomal recessive in about 35 per cent (NCF1, CYBA, NCF2, NCF4, CYBC1).

  • How common

    Roughly 1 in 200,000 to 250,000 live births in the UK and Europe.

  • Diagnostic test

    Neutrophil oxidative burst on dihydrorhodamine 123 (DHR) flow cytometry is the gold standard and also identifies X-linked carrier females.

  • Prophylaxis

    Lifelong co-trimoxazole and itraconazole, with interferon gamma-1b in many patients, dramatically reduce serious infection.

  • Curative options

    Allogeneic haematopoietic stem cell transplant is curative; lentiviral gene therapy for X-linked CGD is an emerging alternative in specialist UK centres.

Why this guide matters

Rare, but far from untreatable.

CGD is uncommon, so many patients wait years for the right diagnosis. The three ideas below shape everything else on this page.

  • Recognise the pattern early

    Unusual organisms, deep abscesses, granulomas or Crohn-like colitis in a child (and sometimes an adult) should prompt DHR testing.

  • Prophylaxis changes the trajectory

    Lifelong co-trimoxazole and itraconazole, with interferon gamma-1b in many patients, dramatically reduce serious infection.

  • Cure is on the table

    Allogeneic stem cell transplant is curative for many patients, and lentiviral gene therapy for X-linked CGD is emerging through UK trials.

How the diagnosis is made

From first suspicion to a genetic answer.

The steps a UK primary immunodeficiency team will normally follow, in order, so you know what to expect and why.

  1. 01

    Assessing

    Recognising the pattern

    Recurrent deep bacterial or fungal infection, unusual organisms (Aspergillus, Burkholderia, Serratia, Nocardia, Chromobacterium), granulomas or Crohn-like colitis in a child prompt suspicion.

  2. 02

    Assessing

    Baseline immunology

    Immunoglobulins, T, B and NK cell subsets and complement help exclude other primary immunodeficiencies before targeted testing.

  3. 03

    Assessing

    Cultures and susceptibility

    Careful microbiology, including deep tissue and abscess samples, is essential because CGD organisms are often unusual and drug-resistant.

  4. 04

    Confirming

    DHR flow cytometry

    Dihydrorhodamine 123 on stimulated neutrophils is the gold-standard functional test; absent or reduced fluorescence confirms CGD and detects X-linked carriers.

  5. 05

    Confirming

    Genetic testing

    A primary immunodeficiency panel covering CYBB, NCF1, CYBA, NCF2, NCF4 and CYBC1 confirms the subtype, guides prognosis and enables family cascade and prenatal testing.

  6. 06

    Preparing

    Imaging and endoscopy

    CT of the chest, abdomen and brain looks for infection and granulomas; endoscopy with biopsy characterises the Crohn-like colitis when present.

  7. 07

    Preparing

    Specialist MDT review

    Care is coordinated by a UK primary immunodeficiency centre with immunology, infectious diseases, haematology, gastroenterology and transplant expertise.

Typical pathway: from first suspicion to a genetic diagnosis in a specialist centre within weeks.

Symptoms

What CGD looks like in real life.

A pattern of unusual, deep infection, granulomas and gut inflammation, sometimes with autoimmune features, in a child or young adult.

  • Recurrent pneumonia

    Often caused by Aspergillus, Staphylococcus aureus, Nocardia, Burkholderia or Serratia, and typically deep-seated.

  • Lymphadenitis and abscesses

    Deep abscesses in liver, brain and perianal region are characteristic and often need drainage as well as antimicrobials.

  • Osteomyelitis and skin sepsis

    Bone infection and recurrent skin infection or dermatitis, sometimes with slow-healing wounds.

  • Granulomas and CGD colitis

    Non-caseating granulomas can obstruct hollow organs; a Crohn-like, fistulising colitis affects many patients.

  • Failure to thrive

    Recurrent infection and gut inflammation can slow growth and puberty, especially in undiagnosed children.

  • Autoimmune features

    Lupus-like disease in female carriers, inflammatory bowel disease and rheumatologic complications occur in a minority.

  • Adult presentation

    A significant subset are diagnosed in adulthood, sometimes after years of unexplained infection or inflammation.

  • Red flag - unusual organism

    A catalase-positive or fungal infection with an organism rarely seen in an immunocompetent host should always prompt CGD testing.

Treatment

How CGD is treated in the UK.

Lifelong antibacterial and antifungal prophylaxis, aggressive treatment of infection, careful management of CGD colitis, and curative HSCT or gene therapy in selected patients.

  • Co-trimoxazole prophylaxis

    Trimethoprim-sulfamethoxazole 480 mg twice daily is lifelong first-line antibacterial prophylaxis and reduces serious infection substantially.

  • Itraconazole prophylaxis

    Lifelong azole antifungal prophylaxis is standard in CGD and lowers the risk of invasive Aspergillus and other mould infections.

  • Interferon gamma-1b

    Subcutaneous Actimmune three times weekly is used in many patients and cut serious infection rates in the landmark CGD trial.

  • Targeted antimicrobials

    Acute infections need early, aggressive, prolonged therapy with agents such as voriconazole, posaconazole, isavuconazole, meropenem or high-dose co-trimoxazole.

  • Surgical drainage

    Abscesses, obstructing granulomas and complex fistulas often need surgery alongside prolonged antimicrobial cover.

  • CGD colitis therapy

    Stepped care with 5-ASA, corticosteroids, immunomodulators and anti-TNF biologics such as infliximab or adalimumab, balanced against infection risk.

  • Haematopoietic stem cell transplant

    Allogeneic HSCT with matched sibling, unrelated or haploidentical donors offers a curative option in UK specialist centres.

  • Gene therapy for X-linked CGD

    Lentiviral gene therapy is an emerging alternative to HSCT for X-linked disease, delivered through UK clinical trials and specialist services.

What this guide is based on

The sources behind every claim on this page.

UK network standards, international immunology society guidance and landmark trials, current at the time of last review.

Key references

Guidelines and standards we relied on.

A quiet reminder

This guide is for information, not medical advice.

Your immunology team knows your history and can tell you which parts apply to you. If you are unwell, contact them without delay.

  • European Society for Immunodeficiencies (ESID). Diagnostic and clinical criteria for chronic granulomatous disease.

  • UK Primary Immunodeficiency Network (UKPIN). Standards for the management of primary immunodeficiency.

  • International Union of Immunological Societies (IUIS). Classification of inborn errors of immunity.

  • The International CGD Study Group. Interferon gamma-1b trial in chronic granulomatous disease (NEJM landmark trial).

Red flags

When CGD needs urgent attention.

A low threshold to contact your immunology team is essential. These are the situations where urgent specialist input is needed.

  • Invasive fungal infection

    Suspected or proven invasive Aspergillus, Scedosporium or other mould infection needs urgent admission and specialist antifungal therapy.

  • Burkholderia or Nocardia infection

    These CGD-associated pathogens are difficult to treat, often disseminate and warrant infectious diseases input from the outset.

  • Brain or liver abscess

    New neurological symptoms, fever with right upper quadrant pain, or unexplained sepsis mandate imaging and prompt drainage plus antimicrobials.

  • Severe CGD colitis flare

    Bloody diarrhoea, fistulas or obstruction need combined gastroenterology and immunology review, and careful balancing of immunosuppression and infection risk.

  • Live vaccine exposure

    Live vaccines such as BCG can cause disseminated infection in CGD; any inadvertent live vaccination needs urgent specialist advice.

  • High-risk environmental exposure

    Handling compost, mulch, gardening dust, stagnant water, hot tubs or building sites can trigger invasive mould infection and needs prompt review.

  • New autoimmune features

    Rashes, arthritis or lupus-like features, especially in female X-linked carriers, deserve a specialist rheumatology and immunology opinion.

  • Growth failure in a child

    Poor growth and delayed puberty in a child with recurrent infection should always prompt formal immunology assessment.

  • Signs of transplant complications

    After HSCT, new rashes, diarrhoea, jaundice or fever need same-day contact with the transplant team.

Living with it

A lifelong condition, with a clear plan.

Four things that make the biggest difference day to day: consistent prophylaxis, sensible environmental precautions, the right vaccines, and connection with peer and family support.

A quiet reminder

Small, steady habits do the heavy lifting.

Daily prophylaxis, avoidance of high-risk environments and prompt escalation of any fever are the routines that keep people with CGD well.

  1. 01 Prevention

    Take prophylaxis every day

    Co-trimoxazole and itraconazole only work if taken consistently; missed doses meaningfully raise infection risk.

  2. 02 Environment

    Avoid mould and dust exposure

    Steer clear of compost, mulching, hay, gardening dust, stagnant water, hot tubs and unfiltered swimming pools.

  3. 03 Vaccines

    Killed vaccines only

    Follow the CGD-specific schedule with your immunology team and avoid live vaccines, including BCG and live oral typhoid.

  4. 04 Support

    Use the CGD community

    The CGD Society and Immunodeficiency UK offer education, peer support and transition support for young adults.

Frequently asked

Everything we get asked about CGD.

Quick answers on genetics, DHR testing, infection risk, prophylaxis, transplant and gene therapy.

  • What is chronic granulomatous disease?

    A rare inherited primary immunodeficiency caused by faults in the NADPH oxidase complex of phagocytes. Without a normal oxidative burst, neutrophils and macrophages cannot kill certain catalase-positive bacteria and fungi, so patients develop recurrent deep infections and granulomas.

  • How is CGD inherited?

    About 65 per cent of cases are X-linked, caused by variants in the CYBB gene, and affect mostly males; carrier females can have mild features. The remaining 35 per cent are autosomal recessive, involving NCF1, CYBA, NCF2, NCF4 or CYBC1. Genetic testing confirms the subtype and enables family cascade testing.

  • How is CGD diagnosed?

    The dihydrorhodamine 123 (DHR) flow cytometry test on stimulated neutrophils is the gold standard. It shows absent or reduced reactive oxygen species and also detects X-linked carriers through their characteristic mosaic pattern. A primary immunodeficiency gene panel then confirms the subtype.

  • What infections should people with CGD look out for?

    Deep infections caused by Aspergillus, Staphylococcus aureus, Burkholderia, Serratia, Nocardia and Chromobacterium are typical. Pneumonia, liver or brain abscesses, osteomyelitis, lymphadenitis and skin infections all warrant early specialist assessment and prolonged targeted therapy.

  • Can CGD be cured?

    Allogeneic haematopoietic stem cell transplant is curative and is increasingly used in UK specialist centres, including Great Ormond Street, Newcastle, Manchester Royal, Sheffield and Cambridge. For X-linked CGD, lentiviral gene therapy is an emerging alternative delivered through clinical trials.

  • What should people with CGD avoid?

    Avoid compost, mulching, gardening dust, hay, stagnant water, hot tubs and unfiltered swimming pools because of invasive mould risk. Live vaccines such as BCG should be avoided. Always tell healthcare professionals about your CGD before any procedure or new medication.

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