Categorical assessment or numeric weight | |
Step 1. Entry criteria | |
Characteristic* clinical or radiologic involvement of a typical organ (eg, pancreas, salivary glands, bile ducts, orbits, kidney, lung, aorta, retroperitoneum, pachymeninges, or thyroid gland [Riedel's thyroiditis]) or pathologic evidence of an inflammatory process accompanied by a lymphoplasmacytic infiltrate of uncertain etiology in one of these same organs | Yes¶ or No |
Step 2. Exclusion criteria: domains and itemsΔ | |
Clinical
Serologic
Radiologic
Pathologic
Known diagnosis of the following:
| Yes or No◊ |
If case meets entry criteria and does not meet any exclusion criteria, proceed to step 3. | |
Step 3. Inclusion criteria: domains and items§ | |
Histopathology | |
| 0 |
| +4 |
| +6 |
| +13 |
Immunostaining¥ | 0 to 16, as follows:
|
Serum IgG4 concentration | |
| 0 |
| +4 |
| +6 |
| +11 |
Bilateral lacrimal, parotid, sublingual, and submandibular glands | |
| 0 |
| +6 |
| +14 |
Chest | |
| 0 |
| +4 |
| +10 |
Pancreas and biliary tree | |
| 0 |
| +8 |
| +11 |
| +19 |
Kidney | |
| 0 |
| +6 |
| +8 |
| +10 |
Retroperitoneum | |
| 0 |
| +4 |
| +8 |
Step 4: Total inclusion points | |
A case meets the classification criteria for IgG4-RD if the entry criteria are met, no exclusion criteria are present, and the total points is ≥20. |
DNA: deoxyribonucleic acid; IgG4: immunoglobulin G4; RNP: ribonucleoprotein.
* Refers to enlargement or tumor-like mass in an affected organ except in 1) the bile ducts, where narrowing tends to occur, 2) the aorta, where wall thickening or aneurysmal dilatation is typical, and 3) the lungs, where thickening of the bronchovascular bundles is common.
¶ If entry criteria are not fulfilled, the patient cannot be further considered for classification as having IgG4-related disease (IgG4-RD).
Δ Assessment for the presence of exclusion criteria should be individualized depending on a patient's clinical scenario.
◊ If exclusion criteria are met, the patient cannot be further considered for classification as having IgG4-RD.
§ Only the highest-weighted item in each domain is scored.
¥ Biopsies from lymph nodes, mucosal surfaces of the gastrointestinal tract, and skin are not acceptable for use in weighting the immunostaining domain.
‡ "Indeterminate" refers to a situation in which the pathologist is unable to clearly quantify the number of positively staining cells within an infiltrate yet can still ascertain that the number of cells is at least 10/high-power field (HPF). For a number of reasons, most often pertaining to the quality of the immunostain, pathologists are sometimes unable to count the number of IgG4+ plasma cells with precision yet even so, can be confident in grouping cases into the appropriate immunostaining result category.