✧ Evidence-based transplant pathology

The Banff Kidney
Interactive Atlas.

Score every lesion. Understand rejection thresholds. Walk through real-world diagnostic patterns. Build a structured allograft biopsy report in one workspace.

Created by Dr Kamlesh Darji, MD

Start scoring Explore cases

Diagnostic categories

Lesion scoring parameters

Core AMR criteria

2024-3

Current reference edition

01 / Interactive workbench

Score a renal allograft biopsy

Choose Banff lesion scores and ancillary findings to see a live, explainable diagnostic interpretation.

Microscopic lesion scores

Teaching example

TUBULOINTERSTITIAL & VASCULAR INJURY

MICROVASCULAR INJURY

CHRONIC INJURY

＋ Additional / optional Banff scores

Antibody, molecular & context

Required for AMR assessment

C4d score

Staining method

Donor-specific antibodies (DSA)

Validated AMR molecular result

Severe PTC basement membrane multilayering (EM)

Acute TMA without other cause

Previous AMR or historical DSA

Inflamed fibrotic neointima (chronic active TCMR II)

Potential confounders

Check only when the competing process is present. The interpretation will become appropriately cautious.

Infection / pyelonephritis / BK nephropathy Recurrent or de novo glomerulonephritis Chronic TMA explaining double contours Alternative cause of inflammation in IFTA

Biopsy adequacy (optional)

Number of glomeruli

Number of arteries

The workbench assumes each score has been assigned using its formal morphological definition. It does not diagnose unscored lesions or substitute for microscopy, EM, serology or clinical correlation.

Live interpretation

Provisional

AMR criteria trace

Generate structured report →

02 / Microscopic reference

Banff lesion score atlas

Search a score, inspect its thresholds, and learn which compartment is assessed.

03 / Diagnostic logic

From lesions to classification

Always score first, then apply the corresponding category criteria. More than one diagnosis can coexist.

Acute TCMR pathway

1Check intimal arteritis: v1 → IIA, v2 → IIB, v3 → III.

2If v0, i≥2 + t2 → IA; i≥2 + t3 → IB.

3i1 + t≥1 or i≥2 + t1 → borderline, provided no qualifying acute TCMR.

4For chronic active TCMR, independently evaluate ti, i-IFTA, t/t-IFTA and inflamed neointima.

AMR / MVI pathway

1Identify qualifying acute lesions (g, ptc, v, unexplained acute TMA) and chronic lesions (cg, severe PTCML).

2Establish antibody interaction: C4d positivity, qualifying g + ptc ≥2, or validated molecular positivity.

3Confirm DSA, or use qualifying C4d as a substitute; distinguish active, chronic active and chronic AMR.

4Below-threshold DSA+ lesions may be probable AMR; moderate MVI with C4d−/DSA− is a separate phenotype.

Chronic injury and mimics

1Grade IFTA by the higher of ci and ct: 1 mild, 2 moderate, 3 severe.

2Do not equate IFTA, cv or ah with a specific rejection mechanism.

3Exclude GN/chronic TMA before using cg for chronic AMR and infection before labeling tubulitis as TCMR.

4Document all qualifying diagnoses plus BK/PVN, drug injury, pyelonephritis and recurrent disease when present.

04 / Active recall

Test your Banff reasoning

Eight clinical-pathologic mini-cases to practice choosing the correct diagnostic category.

Case 01 / 08T-cell-mediated rejection

Your learning progress

0 / 0Correct answers / attempts

Select one answer, then check your reasoning. Cases use formal Banff thresholds and intentionally include common diagnostic traps.

Review the score atlas →

05 / Structured reporting

Report studio

Generate an editable interpretive draft from current workbench values. Review against the actual slides before clinical sign-out.