Treatment specialists

Immunologists help calm immune overreactions, and surgeons help with biopsy or repair as part of your care team.

Immunologists and surgeons: Multidisciplinary teams in diagnosis and management of IgG4-RD

When you’re living with IgG4-related disease (IgG4-RD), it can feel like the problem is “everywhere,” or at least could be, because this illness can affect many organs and can look like other conditions. That’s why many people do best with a multidisciplinary care team: a group of specialists who share information and make decisions together.

In IgG4-RD, getting the diagnosis right often depends on two big things:
(1) understanding how the immune system is behaving, and
(2) proving what a tissue abnormality really is under the microscope. That’s where immunologists and surgeons become especially important.

An immunologist helps your team interpret immune-system signals and manage complicated immune questions over time. A surgeon, in contrast, often helps obtain the tissue (biopsy) needed for a confident diagnosis and can treat structural problems when inflammation or scarring causes blockage or damage. ^1-5

They will probably not be the main doctor you see every clinic visit, but they are often key partners at the moments when your team needs the clearest answers, or the safest next step. ³

Immunologist: A doctor who studies the immune system

An immunologist is a medical doctor who specializes in the immune system, that is, how your body’s defenses work when they are overactive, underactive, or misdirected. Many immunologists are also trained as allergists, meaning they can treat allergies and asthma and complex immune disorders.

In IgG4-RD, the immune system is not just “overactive”, it can be misdirected, sending inflammatory cells into organs and sometimes leading to fibrosis (scarring) over time. ^1-3 An immunologist can be especially helpful when your care team needs a deeper look at immune function, immune “signals,” and infection risk while on immune-suppressing treatment.⁴

How immunologists can help in IgG4-RD

In IgG4-RD, the immune system is driving inflammation and (over time) can drive scarring, called fibrosis. ^1–2

Immunologists can help your team by:

Clarifying immune overlap. Some people with IgG4-RD also have allergy-type features (like asthma, sinus disease, eczema, high IgE, or high levels of eosinophils in the blood). An immunologist can help interpret whether those findings are part of your IgG4-RD picture, a separate allergic disease, or something else. ^4–5

Safety planning with immune therapy. When treatments reduce immune activity, teams often need to think carefully about infection risk, vaccine planning, and whether additional immune evaluation is needed. Immunologists are trained to assess immune defense problems and advise on monitoring. ^4–5

Supporting long-term chronic care. IgG4-RD must be managed over years, not weeks. Immunologists can be valuable team members when the immune story is complicated, especially if there are frequent infections, unusual lab patterns, or questions about immune suppression tolerance. ^4–5

Not every person with IgG4-RD needs an immunologist. But when the immune system story is complicated, they can be a valuable voice on the team.³

Surgeon: Using procedures to diagnose or fix a problem

A surgeon is a physician with specialized training to treat disease using operations or procedures, before, during, and after surgery. ^5,6 There are many types of surgeons (for example, general, vascular, cardiothoracic, neurosurgery, orthopedic), and each one focuses on a different part of the body. ^5,7

In IgG4-RD, a surgeon’s role is often less about “major surgery” and more about helping your team answer an important question: What exactly is this tissue—and what is causing it?

How surgeons can help in IgG4-RD

IgG4-RD can form tumefactive lesions—swollen, mass-like areas that can mimic cancer or infection on imaging and even during surgery. Because of that, many people need a biopsy (a tissue sample) so pathology experts can look for the characteristic tissue pattern of IgG4-RD and rule out dangerous mimics.^1,2 Sometimes the only way of approaching a biopsy is through a surgical procedure, as opposed to a biopsy with a needle that is guided by a CT scan or ultrasound.

A key surgical principle in suspected autoimmune pancreatitis/IgG4-RD is: get the diagnosis right early to avoid unnecessary major surgery, because management can be very different from cancer.⁸ That is one reason surgeons who know these conditions often work closely with gastroenterology, radiology, rheumatology, and pathology to choose the safest way to confirm the diagnosis (for example, targeted biopsy approaches rather than immediate big operations).

Surgeons can help by:

Choosing the safest tissue strategy: recommending (and sometimes performing) the best biopsy approach when tissue is needed, balancing diagnostic yield with safety. ^2,3,8

Protecting organs when structure is threatened: treating or relieving complications from inflammation or fibrosis—such as obstruction, compression, or damage to ducts/vessels—often in coordination with the medical plan to control immune activity.^2,3

Co-managing “localized” disease thoughtfully: even when a lesion is removed or repaired, the team still considers whether there is systemic risk (other organs) and whether medical therapy and monitoring are needed afterward.^1–3

Stent placements in the urinary tract: when stents are required in the ureters because of retroperitoneal fibrosis, these are usually placed by urologists, surgical subspecialists who focus on the genitourinary tract. These stents are placed via cystoscopy – a scope that looks into the bladder through the urethra.

Nephrostomy tubes: if both ureters are so tightly involved by the fibrosis of RPF, it may be necessary for nephrostomy tubes to be placed. These are tubes inserted right into the kidneys under radiology guidance to drain urine from the kidneys. Hopefully these tubes are required on only a temporary basis but when necessary they are placed by a urologist, too.

One patient story shows why this matters: a person was told they might need a major cancer surgery (a Whipple procedure) before the condition was correctly recognized as IgG4-RD—an example of how IgG4-RD can imitate serious surgical diseases

Watch video

What’s involved in a biopsy

A biopsy is a procedure where a clinician or surgeon removes a small sample of tissue or cells so it can be tested in a laboratory. The main purpose is to diagnose the cause of an abnormal finding—most commonly to determine whether it is cancer, an infection, or a type of inflammation.

Most biopsies fall into two broad method types:

• Needle biopsies. These use a needle passed through the skin to the area of concern to remove cells or a small piece of tissue. Common needle approaches include fine-needle aspiration and core needle biopsy.

• Surgical (open) biopsies. These remove a larger piece of tissue (or sometimes the whole abnormal area) using a procedure in an operating room or procedure suite.

During the procedure, the area is made comfortable with local anesthesia (numbing medicine) and sometimes sedation or general anesthesia, depending on the site and the type of biopsy. After the sample is collected, it is sent to a lab where a pathologist examines it to distinguish normal from abnormal cells and to identify the underlying disease process.

Surgeons may perform an open or excisional biopsy to secure adequate tissue for diagnosis.

How immunologists, surgeons, and rheumatologists work together

Think of IgG4-RD care like building a clear map.

• Your main treating doctor (often a rheumatologist or another specialist) helps lead the plan over time.

• The immunologist helps interpret the immune system “signals” and supports safe immune-targeting treatment decisions when things are complex.

• The surgeon helps when your team needs tissue confirmation (biopsy) or when inflammation/scarring has created a structural problem that needs a procedure.

This shared communication helps your team identify which organs are involved, interpret imaging and tests in context, and adjust treatments safely.

Questions to ask an immunologist

1. “Do any of my lab patterns suggest allergy overlap (IgE/eosinophils) versus something separate?”

2. “How will we monitor infection risk while I’m on immune-directed treatment?”

3. “Are there immune function tests you recommend because of my infection history (if any)?”

4. “How should vaccines be timed with my treatment plan?”

5. “Which symptoms should prompt me to call you versus my rheumatologist or primary doctor?”

Questions to ask a surgeon

1. “What is the least invasive way to get enough tissue for a confident diagnosis?”

2. “If we do a biopsy, what result would change the plan?”

3. “Will pathology be reviewed by a team familiar with IgG4-RD patterns?”

4. “Is there a non-surgical alternative to manage obstruction/compression first?”

5. “If surgery is needed, how will you coordinate with rheumatology/immunology for long-term management afterward?

Summary

When immunologists or surgeons are involved in IgG4-RD care, it is typically to support specific clinical needs, such as immune-system evaluation, tissue confirmation (biopsy), or procedural management of organ or duct/vessel complications related to inflammation or fibrosis.

Their involvement commonly reflects a coordinated approach to diagnosis and management, where findings from symptoms, imaging, laboratory testing, and pathology are integrated to guide the safest and most appropriate treatment plan.

Optimal care in IgG4-RD is multidisciplinary, with clear communication among specialists so decisions are based on a shared understanding of the full clinical picture.

References

1. Stone JH, Zen Y, Deshpande V. IgG4-Related Disease. N Engl J Med. 2012;366:539–551. https://www.nejm.org/doi/abs/10.1056/NEJMra1104650

2. Peyronel F, Della-Torre E, Maritati F, et al. IgG4-related disease and other fibro-inflammatory conditions. Nat Rev Rheumatol. 2025;21:275–290. doi:10.1038/s41584-025-01240-x. https://www.nature.com/articles/s41584-025-01240-x

3. IgG4ward Foundation. It takes a team: understanding the specialists who support IgG4-related disease. https://igg4ward.org/igg4rd-care-team-specialists/

4. Cleveland Clinic. What is an allergist? When to see one & what to expect. (Last updated Aug 18, 2022.) https://my.clevelandclinic.org/health/articles/24053-allergist

5. Cleveland Clinic. Surgeon: definition & types. (Last updated Jul 3, 2025.) https://my.clevelandclinic.org/health/articles/surgeon

6. American College of Surgeons. Surgery FAQ (What is surgery?). https://www.facs.org/for-patients/surgery-faq/

7. American College of Surgeons. What are the surgical specialties? https://www.facs.org/for-medical-professionals/education/online-guide-to-choosing-a-surgical-residency/guide-to-choosing-a-surgical-residency-for-medical-students/faqs/specialties/

8. Mayo Clinic. Biopsy: types of biopsy procedures used to diagnose cancer. https://www.mayoclinic.org/diseases-conditions/cancer/in-depth/biopsy/art-20043922

9. Mayo Clinic. Needle biopsy. https://www.mayoclinic.org/tests-procedures/needle-biopsy/about/pac-20394749

10. IgG4ward! Foundation. IgG4ward! Jam Video Series – Video 6: Understanding the Extent of the Disease and Monitoring Over Time for Relapse with Dr. Mollie Carruthers. IgG4ward! Foundation. https://igg4ward.org/resources/igg4ward-jam-video-series-video-6-understanding-the-extent-of-the-disease-and-monitoring-over-time-for-relapse-with-dr-mollie-carruthers/