IgG4ward! Jam Video Series- Video 5 -Making a Correct IgG4-RD Diagnosis with Dr. Guy Katz

Making a Correct IgG4-RD Diagnosis

IgG4-related disease (IgG4-RD) can be notoriously difficult to diagnose, and many patients endure a long, winding road before receiving a correct IgG4-RD diagnosis. In this session from the recent IgG4ward! JAM, Dr. Guy Katz from the Massachusetts General Hospital shared his wisdom into the diagnostic process, highlighting the complexities and emphasizing best practices in approaching an IgG4-RD diagnosis efficiently. Some key takeaways from Dr. Katz’s talk include:

Making a diagnosis can be complex.

• IgG4-RD has many mimickers making accurate diagnosis challenging at times.

How the Classification Criteria can facilitate arriving at the correct diagnosis.

• Dr. Katz helps to explain how this helps to provide a structured approach (clinical, lab, imaging) to guide diagnosis.

Key diagnostic tools.

• Imaging: Helps visualize organ involvement (e.g., pancreas, bile ducts, salivary glands).

• Lab Tests: Serum IgG4 levels can be elevated but aren’t definitive; other labs must be considered.

• Histopathology: Classic findings (e.g., storiform fibrosis) are helpful but can overlap with other diseases or be affected by pre-treatment.

• Treatment Response: Improvement with therapy can reinforce a suspected diagnosis, though it’s not a formal “test.”

• Dr. Katz then shows how physicians combine all the tools and gained knowledge to arrive at a diagnosis.

Case Examples are presented to help give a “real world” understanding of making a correct diagnosis.

Four examples demonstrate how these concepts are applied in practice. Great questions from the audience of JAM attendees further highlighted Dr. Katz’s points.

Watch the full video below to learn more: