Modified NIH Activity and Chronicity Indices (Lupus Nephritis)
The MODIFIED NIH ACTIVITY AND CHRONICITY INDICES for lupus nephritis, from the 2018 ISN/RPS revision (Bajema and colleagues, Kidney Int 2018).
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Example
- ACTIVITY index. Endocapillary hypercellularity
- 2
- ACTIVITY index. Neutrophils and/or karyorrhexis
- 1
- ACTIVITY index. Fibrinoid necrosis
- 1
- ACTIVITY index. Hyaline deposits
- 2
- ACTIVITY index. Cellular and/or fibrocellular crescents
- 1
- ACTIVITY index. Interstitial inflammation
- 1
- CHRONICITY index. Total glomerulosclerosis
- 1
- CHRONICITY index. Fibrous crescents
- 0
- CHRONICITY index. Tubular atrophy
- 1
- CHRONICITY index. Interstitial fibrosis
- 1
Result: activity index 10 of 24 and chronicity index 3 of 12.
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What the result means
- Purpose
- Introduced by the 2018 revision to REPLACE the A / A-C / C subscripts on classes III and IV.
- Two indices
- Activity 0-24 and chronicity 0-12. NEVER added together: they measure opposite things.
- Why 24
- Six components at 0-3 would cap at 18. The extra 6 is entirely the two doubled terms.
- Two rubrics
- Glomerular = percent of glomeruli. Interstitial = mild/moderate/severe. Same range, different question.
- Not 1984
- Karyorrhexis moved from fibrinoid necrosis to neutrophils, so old and new scores are not comparable.
- Scope
- Histology only. Does not assign the ISN/RPS class, measure function, or indicate immunosuppression.
What you enter
- ACTIVITY index.
- ACTIVITY index.
- ACTIVITY index.
- ACTIVITY index.
- ACTIVITY index.
- ACTIVITY index.
- CHRONICITY index.
- CHRONICITY index.
- CHRONICITY index.
- CHRONICITY index.
Full field descriptions
- ACTIVITY index. Endocapillary hypercellularity. Weight x1. Rubric: 0 = Not present; 1 = Under 25 percent of glomeruli; 2 = 25 to 50 percent of glomeruli; 3 = Over 50 percent of glomeruli
- ACTIVITY index. Neutrophils and/or karyorrhexis. Weight x1. Rubric: 0 = Not present; 1 = Under 25 percent of glomeruli; 2 = 25 to 50 percent of glomeruli; 3 = Over 50 percent of glomeruli
- ACTIVITY index. Fibrinoid necrosis. Weight x2. Rubric: 0 = Not present; 1 = Under 25 percent of glomeruli; 2 = 25 to 50 percent of glomeruli; 3 = Over 50 percent of glomeruli
- ACTIVITY index. Hyaline deposits (wire loops and/or hyaline thrombi). Weight x1. Rubric: 0 = Not present; 1 = Under 25 percent of glomeruli; 2 = 25 to 50 percent of glomeruli; 3 = Over 50 percent of glomeruli
- ACTIVITY index. Cellular and/or fibrocellular crescents. Weight x2. Rubric: 0 = Not present; 1 = Under 25 percent of glomeruli; 2 = 25 to 50 percent of glomeruli; 3 = Over 50 percent of glomeruli
- ACTIVITY index. Interstitial inflammation. Weight x1. Rubric: 0 = Not present; 1 = Mild; 2 = Moderate; 3 = Severe
- CHRONICITY index. Total glomerulosclerosis (global AND segmental). Weight x1. Rubric: 0 = Not present; 1 = Under 25 percent of glomeruli; 2 = 25 to 50 percent of glomeruli; 3 = Over 50 percent of glomeruli
- CHRONICITY index. Fibrous crescents. Weight x1. Rubric: 0 = Not present; 1 = Under 25 percent of glomeruli; 2 = 25 to 50 percent of glomeruli; 3 = Over 50 percent of glomeruli
- CHRONICITY index. Tubular atrophy. Weight x1. Rubric: 0 = Not present; 1 = Mild; 2 = Moderate; 3 = Severe
- CHRONICITY index. Interstitial fibrosis. Weight x1. Rubric: 0 = Not present; 1 = Mild; 2 = Moderate; 3 = Severe
How this is calculated
- Weights
- ONLY fibrinoid necrosis and cellular/fibrocellular crescents are x2, and only in activity. Chronicity is unweighted.
- Denominator
- Percent of glomeruli IN THE SAMPLE, so an inadequate biopsy can only LOWER the score.
Bajema IM, Wilhelmus S, Alpers CE, et al. Revision of the International Society of Nephrology/Renal Pathology Society classification for lupus nephritis: clarification of definitions, and modified National Institutes of Health activity and chronicity indices. Kidney Int. 2018;93(4):789-796. Read the source ↗
A reference and educational tool. Not medical, legal, or financial advice, and not a substitute for clinician judgment.