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PubMed This is a summary of 19 peer-reviewed journal articles Updated
Immunology · Good Syndrome

Diagnosis, Blood Work, and Distinguishing Good Syndrome

At a Glance

Good syndrome is diagnosed by confirming a thymoma and a characteristic immune deficiency: very low antibodies, markedly reduced B cells, and often abnormal T-cell counts. Doctors also use imaging, pathology, HIV and CVID testing, and a review of medications and protein loss to exclude other causes.

Diagnosing Good syndrome requires clinical detective work. Because the condition is rare, your doctors evaluate a pattern of laboratory and clinical findings. They must confirm two main things: the presence of a thymoma (a tumor of the thymus gland) and a specific pattern of immune system failure [1][2].

It is important to note that the timing varies. For some, the immune deficiency is found first; for others, it appears years after the thymoma has been surgically removed [3].

Imaging and Pathology: Confirming the Thymoma

The first step usually involves imaging the chest to look for a mass in the anterior mediastinum (the space in the chest behind the breastbone).

  • Chest CT: This is the primary tool used to see the size and shape of the tumor and to check if it has grown into nearby tissues [4].
  • PET Scan: Sometimes used to help stage the disease or identify other issues, though a PET scan cannot reliably distinguish a thymoma from a lymphoma on its own [5][6].
  • Pathology Report: After the tumor is biopsied or removed, a pathologist looks at the cells under a microscope. This establishes the final diagnosis. You will likely see WHO Classification types such as Type A, AB, B1, B2, or B3 [7]. These labels describe how much the tumor looks like normal thymus tissue and how many lymphocytes (immune cells) are mixed in with the tumor cells [7][8].

The Immunology Workup

To evaluate your immune system, doctors look at several tests. No single test confirms Good syndrome, but this pattern is typical:

  1. Quantitative Immunoglobulins: This measures the levels of three main types of antibodies: IgG, IgA, and IgM. In Good syndrome, these are typically very low [9][10].
  2. B-Cell Count (Flow Cytometry): Doctors look for CD19 and CD20 markers. In Good syndrome, these B cells are often markedly reduced or virtually absent [11][12].
  3. T-Cell Subsets: These tests count your CD4 (“helper”) and CD8 (“killer”) T cells. A common finding is an inverted CD4/CD8 ratio, meaning you have fewer helper cells than killer cells, which impairs your overall defense system [9][13].
  4. NK-Cell Counts: Your report may also list CD16/CD56 cells (Natural Killer cells), which can also be low [11][14].

Note: Vaccine-antibody testing is sometimes used to see how your immune system responds to shots. However, once you start immunoglobulin replacement (IVIG), these tests can be difficult to interpret because the donor antibodies affect the results.

Telling Good Syndrome Apart from Other Conditions

Because low antibodies can be caused by many things, your doctor must rule out other causes:

  • CVID (Common Variable Immunodeficiency): Like Good syndrome, CVID causes low antibodies and can be diagnosed in adulthood, often without a family history. However, Good syndrome is distinguished by the presence of a thymoma, more severe T-cell abnormalities, and markedly reduced B cells (whereas most CVID patients have some circulating B cells) [15][12].
  • HIV: Since both HIV and Good syndrome can cause low CD4 counts and unusual infections, an HIV test is a standard part of the process [16][17].
  • Secondary Causes: Doctors will thoroughly check if your immune system was weakened by medications (like rituximab or steroids), chemotherapy, or by losing proteins through your kidneys or gut [18][19].

Understanding Your Reports

You may see these technical terms on your lab or pathology results:

  • Hypogammaglobulinemia: The medical term for low levels of antibodies in the blood [9].
  • Lymphopenia: A general term for a low count of white blood cells (lymphocytes) [11].
  • Anterior Mediastinum: The specific area in your chest where the thymus is located [4].
  • Flow Cytometry: The specialized lab technique used to count and sort different types of immune cells [11].

Common questions in this guide

How is Good syndrome diagnosed?
Doctors look for both a thymoma and a characteristic immune deficiency. Evaluation may include chest CT, thymoma pathology, immunoglobulin levels, B-cell and T-cell counts, NK-cell counts, and testing for other causes of low antibodies.
What blood tests are used to evaluate Good syndrome?
Quantitative IgG, IgA, and IgM tests measure the main antibody levels in the blood. Flow cytometry can count B cells using CD19 and CD20 markers and assess CD4 and CD8 T-cell subsets and CD16 and CD56 natural killer cells.
What do CD19, CD20, and the CD4/CD8 ratio mean on my report?
CD19 and CD20 help identify B cells, which are often greatly reduced or absent in Good syndrome. An inverted CD4/CD8 ratio means there are fewer helper T cells than killer T cells and may indicate impaired immune defense, but your doctor must interpret it with your other results.
How is Good syndrome different from common variable immunodeficiency?
Both conditions can cause low antibody levels, but Good syndrome occurs with a thymoma and often includes markedly reduced B cells and more severe T-cell abnormalities. People with common variable immunodeficiency usually have some circulating B cells and do not have a thymoma.
Can IVIG affect vaccine antibody test results?
Yes. Donor antibodies in IVIG can make vaccine-antibody levels difficult to interpret because the test may detect antibodies supplied by the treatment. Ask your immunologist whether the test timing and result are reliable in your situation.
What other causes of low antibodies are doctors likely to rule out?
Doctors may test for HIV and review medicines such as rituximab or steroids, as well as prior chemotherapy. They may also check for protein loss through the kidneys or digestive tract and consider common variable immunodeficiency.

Questions to Ask Your Doctor

Curated prompts to bring to your next appointment.

  1. 1.What are my absolute counts for CD19/CD20 B cells, and how do they impact my diagnosis?
  2. 2.Does my flow cytometry show an inverted CD4/CD8 ratio, and what does that mean for my risk of unusual infections?
  3. 3.Can you walk me through my pathology report—specifically the WHO thymoma subtype and whether there was any local invasion?
  4. 4.Since my B cells are low, are my vaccine-antibody titer tests reliable, or does my IVIG interfere with the results?
  5. 5.How did you rule out other causes for my low antibodies, such as medication effects or common variable immunodeficiency (CVID)?

Questions For You

Tap a prompt to share your answer — we'll use it plus this page's context to start a tailored conversation.

References

References (19)
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    Immunodeficiency and thymoma in Good syndrome: Two sides of the same coin.

    Guevara-Hoyer K, Fuentes-Antrás J, Calatayud Gastardi J, Sánchez-Ramón S

    Immunology letters 2021; (231()):11-17 doi:10.1016/j.imlet.2020.12.010.

    PMID: 33418010
  2. 2

    Understanding the uncommon: Insights into thymoma associated immunodeficiency.

    Lim XR, Leung BPL, Tan ETM, et al.

    Asian Pacific journal of allergy and immunology 2026; (44(2)):383-391 doi:10.12932/AP-080724-1887.

    PMID: 39955639
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    Immunodeficiency and Thymoma: A Case Report on Good Syndrome, a Diagnosis Frequently Missed and Forgotten.

    Tang ASO, Loh WH, Wong QY, et al.

    The American journal of case reports 2021; (22()):e928659 doi:10.12659/AJCR.928659.

    PMID: 33712551
  4. 4

    State of the Art: MR Imaging of Thymoma.

    Carter BW, Benveniste MF, Truong MT, Marom EM

    Magnetic resonance imaging clinics of North America 2015; (23(2)):165-77.

    PMID: 25952513
  5. 5

    Anterior mediastinal solid tumours in adults: characterisation using dynamic contrast-enhanced MRI, diffusion-weighted MRI, and FDG-PET/CT.

    Yabuuchi H, Matsuo Y, Abe K, et al.

    Clinical radiology 2015; (70(11)):1289-98.

    PMID: 26272529
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    Positron emission tomography/computed tomography as a clinical diagnostic tool for anterior mediastinal tumors.

    Watanabe T, Shimomura H, Mutoh T, et al.

    Surgery today 2019; (49(2)):143-149 doi:10.1007/s00595-018-1712-1.

    PMID: 30198048
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    Liver Metastasis of Thymoma: Case Report and Review of the Literature.

    Mallick J, Peterson JM, Pina-Oviedo S, et al.

    International journal of surgical pathology 2023; (31(5)):755-760 doi:10.1177/10668969221115818.

    PMID: 36259324
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    PAX5 and CD70 are expressed in thymic carcinoma but not in atypical thymoma (WHO type B3 thymoma): an immunohistochemical analysis of 60 cases.

    Weissferdt A, Moran C

    Journal of clinical pathology 2024; (77(11)):761-765 doi:10.1136/jcp-2023-209070.

    PMID: 37696593
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    Prevention of infectious diseases in patients with Good syndrome.

    Multani A, Gomez CA, Montoya JG

    Current opinion in infectious diseases 2018; (31(4)):267-277 doi:10.1097/QCO.0000000000000473.

    PMID: 29878906
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    Good's Syndrome Patients Hospitalized for Infections: A Single-Center Retrospective Study.

    Sun X, Shi J, Wang M, et al.

    Medicine 2015; (94(47)):e2090 doi:10.1097/MD.0000000000002090.

    PMID: 26632723
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    In-depth blood immune profiling of Good syndrome patients.

    Torres-Valle A, Aragon L, Silva SL, et al.

    Frontiers in immunology 2023; (14()):1285088 doi:10.3389/fimmu.2023.1285088.

    PMID: 38035080
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    Good's Syndrome: Time to Move on From Reviewing the Past.

    Kabir A, Alizadehfar R, Tsoukas CM

    Frontiers in immunology 2021; (12()):815710 doi:10.3389/fimmu.2021.815710.

    PMID: 35095915
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    [Good's syndrome developing hemophagocytic lymphohistiocytosis following thymectomy].

    Yamada M, Yoshida M, Oiwa S, et al.

    [Rinsho ketsueki] The Japanese journal of clinical hematology 2020; (61(3)):268-273 doi:10.11406/rinketsu.61.268.

    PMID: 32224589
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    [Good's syndrome. Report of case].

    Herrera-Sánchez DA, León-Pedroza JI, Vargas-Camaño ME, Castrejón-Vázquez MI

    Revista alergia Mexico (Tecamachalco, Puebla, Mexico : 1993) 2017; (64(2)):235-240 doi:10.29262/ram.v64i2.194.

    PMID: 28658732
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    Good syndrome: an adult-onset immunodeficiency remarkable for its high incidence of invasive infections and autoimmune complications.

    Malphettes M, Gérard L, Galicier L, et al.

    Clinical infectious diseases : an official publication of the Infectious Diseases Society of America 2015; (61(2)):e13-9 doi:10.1093/cid/civ269.

    PMID: 25828999
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    Recurrent Campylobacter Enteritis in Patients with Hypogammaglobulinemia: Review of the Literature.

    Najjar I, Paluca F, Loukidis K, Tarr PE

    Journal of clinical medicine 2020; (9(2)) doi:10.3390/jcm9020553.

    PMID: 32085573
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    Progressive multifocal leukoencephalopathy associated with thymoma with immunodeficiency: a case report and literature review.

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    BMC neurology 2018; (18(1)):37 doi:10.1186/s12883-018-1041-4.

    PMID: 29631544
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    Case report: Persistent hypogammaglobulinemia in thymoma-associated myasthenia gravis: the impact of rituximab or Good's syndrome?

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This page is for informational purposes only and does not constitute medical advice. Your immunologist, oncologist, and pathologist can interpret your Good syndrome tests and pathology in the context of your care.

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