Tokyo Guidelines — Cholangitis

Formula

A — systemic inflammation

Fever above 38 °C and/or rigors; or WBC below 4 or above 10 ×10⁹/L, or CRP ≥ 1 mg/dL.

B — cholestasis

Total bilirubin ≥ 2 mg/dL; or ALP, γGT, AST or ALT above 1.5 × the upper limit of normal.

C — imaging

Biliary dilatation; or evidence of the aetiology (stricture, stone, stent).

Grade III organ dysfunction

Cardiovascular, neurological, respiratory, renal, hepatic or haematological, at the TG18 thresholds. Any one is sufficient.

Grade II criteria

WBC above 12,000 or below 4,000/mm³; fever ≥ 39 °C; age ≥ 75; bilirubin ≥ 5 mg/dL; albumin below 0.7 × lower limit of normal. Two are required.

• Severity is assessed top-down. A patient with organ dysfunction is Grade III whether or not any Grade II criteria are met — the counts do not add together.
• Three thresholds appear twice at different values, and mixing them up is the commonest error: fever is 38 °C for diagnosis but 39 °C for Grade II; bilirubin is 2 mg/dL for diagnosis but 5 mg/dL for Grade II; white cell count is outside 4–10 ×10⁹/L for diagnosis but outside 4,000–12,000/mm³ for Grade II.
• Grade II requires TWO of its five criteria. Cholecystitis, confusingly, requires only ONE of its four — the two Tokyo scores differ here.
• The grade is not fixed at presentation. TG18 explicitly expects reassessment, and a Grade I patient who fails to respond within 24 hours is managed as though escalated.
• TG18 kept the TG13 severity grading for cholangitis unchanged; the 2018 revision altered the diagnostic performance data and management flowchart rather than the grading table.

Interpreting the result

Read the diagnosis and the grade as two separate answers. A suspected diagnosis is not a weaker version of a definite one for treatment purposes: a patient can be Grade III on a suspected diagnosis and needs drainage just as urgently. The grade maps onto timing. Grade III means urgent biliary drainage alongside organ support, and the classic error here is waiting for the patient to stabilise before decompressing — they will not stabilise until the biliary tree is drained, because the sepsis is being driven by an obstructed, infected duct under pressure. Grade II means early drainage rather than a trial of antibiotics. Grade I permits initial medical management, but with an explicit 24-hour review: no response by then is an indication for drainage. Because the grade can change within hours, it should be recalculated rather than carried forward from the admission note.

What the Tokyo Guidelines — Cholangitis needs (8 inputs)

A-1: Fever above 38 °C and/or shaking chills

Note this is a lower threshold than the 39 °C used in the Grade II severity criteria. The two temperatures do different jobs and are frequently conflated.

A-2: Evidence of an inflammatory response

White cell count below 4 or above 10 ×10⁹/L, or CRP of 1 mg/dL or above.

B-1: Jaundice

Total bilirubin of 2 mg/dL or above. Again lower than the 5 mg/dL used for Grade II severity.

B-2: Abnormal liver function tests

ALP, γGT, AST or ALT above 1.5 times the upper limit of normal. Any one of the four counts.

C-1: Biliary dilatation on imaging

Ultrasound, CT, MRCP or EUS all count.

C-2: Evidence of the aetiology on imaging

A stricture, a stone or a stent. Duct dilatation is not required if the cause itself is visible.

Organ dysfunction (six systems)

Cardiovascular (dopamine ≥ 5 µg/kg/min or any noradrenaline), neurological (disturbed consciousness), respiratory (PaO₂/FiO₂ below 300), renal (oliguria or creatinine above 2.0 mg/dL), hepatic (PT-INR above 1.5), haematological (platelets below 100,000/mm³). Any one makes it Grade III.

Grade II criteria (five items)

White cell count above 12,000 or below 4,000/mm³; fever 39 °C or above; age 75 or over; bilirubin 5 mg/dL or above; albumin below 0.7 × the lower limit of normal. Any TWO make it Grade II.

Units. Bilirubin thresholds are given in mg/dL: 2 mg/dL for diagnosis is about 34 µmol/L, and 5 mg/dL for Grade II is about 86 µmol/L — divide µmol/L by 17.1 to convert. Creatinine above 2.0 mg/dL for renal dysfunction is about 177 µmol/L. White cell counts appear in two conventions in the original guideline: ×10⁹/L for the diagnostic criteria and per mm³ for the Grade II criteria, but these are the same units — 10 ×10⁹/L is 10,000/mm³.

What it returns

Diagnostic status

Definite, suspected, or criteria not met. Definite requires an item from all three of A, B and C.

Severity grade

Grade I (mild), II (moderate) or III (severe). Assessed top-down, so organ dysfunction settles it regardless of anything else.

Which organ systems are failing

Listed explicitly, because the grade alone does not tell the receiving team what needs supporting.

How it is calculated

The Tokyo Guidelines were built to solve a diagnostic problem that Charcot's triad had created. The triad is specific enough that its presence more or less confirms cholangitis, but its sensitivity is poor — most patients with proven cholangitis do not have all three findings — so a triad-based approach systematically under-diagnoses the condition in which delay is most costly. The guideline group therefore replaced a single conjunctive rule with a three-category framework built from data available in any emergency department: a marker of systemic inflammation, a marker of cholestasis, and imaging. Requiring one item from each for a definite diagnosis preserves specificity, while allowing A plus either B or C to raise suspicion preserves sensitivity for the patient who needs treating before imaging is complete. Severity grading was constructed separately, around the observation that what distinguishes patients is not how loudly they present but whether organs are failing and how much physiological reserve they have — which is why age and albumin sit alongside white cell count and bilirubin in the Grade II list.

Facts & figures

Evidence

How it compares

Pearls & pitfalls

• Three parameters appear twice at different thresholds. Fever is 38 °C for diagnosis and 39 °C for Grade II; bilirubin is 2 mg/dL then 5 mg/dL; white cell count is outside 4–10 ×10⁹/L then outside 4,000–12,000/mm³. Carrying the diagnostic value into the severity assessment over-grades the patient.
• Grade II needs TWO criteria for cholangitis but only ONE for cholecystitis. The two Tokyo scores are not symmetrical and this is where they most often get confused.
• Severity is assessed top-down, not additively. One organ dysfunction is Grade III regardless of how many Grade II criteria are also present.
• Charcot's triad is not the diagnostic standard and has not been since TG07. It is specific but insensitive, so most patients with cholangitis do not have all three.
• A suspected diagnosis still needs treating. Grade III on a suspected diagnosis is a drainage emergency; the diagnostic tier is not a measure of urgency.
• Do not defer drainage to stabilise a Grade III patient. The sepsis is driven by an obstructed infected duct under pressure, and it will not settle until that is decompressed.
• Recalculate the grade during the admission. It is a snapshot, and a Grade I patient failing to respond by 24 hours is an indication for drainage.
• Take blood cultures before the first dose of antimicrobials, and send bile for culture at the time of drainage — the yield from bile is high and it frequently changes therapy.

Critical actions

• Grade III: arrange urgent biliary drainage and provide organ support in parallel, not sequentially.
• Grade II: arrange early biliary drainage rather than a trial of antibiotics alone.
• Grade I: start antimicrobials with an explicit 24-hour review point, and drain if there is no response.
• Take blood cultures before antimicrobials and bile cultures at drainage in every grade.
• Choose the drainage route by availability and anatomy — ERCP first line, with percutaneous transhepatic or EUS-guided drainage as alternatives.
• Recalculate the grade at each review rather than carrying the admission grade forward.
• Plan definitive treatment of the underlying cause, usually cholecystectomy or stone clearance, once the acute episode has settled.

Why this score exists

The guideline's central editorial decision was to stop treating diagnosis as a single conjunctive rule. Charcot's triad had held for over a century precisely because when all three are present the diagnosis is nearly certain — but that is a property of specificity, and using a specific rule as a gate for a disease whose treatment is time-critical means the patients you miss are the ones who most needed finding. Splitting the criteria into three categories and allowing partial combinations to raise suspicion converts the framework from a confirmation test into a triage tool, which is what the clinical problem actually requires. The severity grading reflects a second judgement: that reserve matters as much as the acute insult, which is why age and albumin appear alongside the inflammatory markers.

About the creator

• Seiki Kiriyama

  First author, TG13 and TG18 cholangitis diagnostic criteria and severity grading

  Led the cholangitis diagnostic criteria and severity grading chapters of both the 2013 and 2018 guidelines.

• Kazuto Kozaka

  Co-author of the TG18 cholangitis diagnostic criteria and severity grading chapter.

• Tadahiro Takada

  Chair of the Tokyo Guidelines revision committee

  Led the Tokyo Guidelines programme across the 2007, 2013 and 2018 editions.

Limitations

• The diagnostic criteria depend on imaging being performed, and category C is often the missing element rather than genuinely absent — which can under-call the diagnosis in a patient who has not yet been scanned.
• Several items are subjective or laboratory-dependent, and the guideline does not specify which imaging modality or which local reference range should be used.
• The severity grading is consensus-derived rather than regression-derived, so the Grade II item list and the two-of-five rule are expert judgement rather than a fitted model.
• The albumin criterion is expressed relative to the local lower limit of normal rather than an absolute value, which introduces between-laboratory variation into the grade.
• Grading is a snapshot with no built-in mechanism for the trajectory, despite the guideline expecting reassessment — a deteriorating Grade I and a stable Grade I look identical in the output.
• Validation has largely been retrospective and in populations where ERCP is readily available; performance where drainage is not promptly accessible is less well characterised.
• It does not identify the cause, choose the drainage route, or indicate antimicrobial selection, all of which need separate decisions.

If you are the patient

Cholangitis is an infection in the bile ducts, the tubes that carry bile from the liver to the gut. It usually happens because something — most often a gallstone — is blocking a duct, so the bile cannot drain and becomes infected. It can make people very unwell quickly. The Tokyo Guidelines are a checklist doctors use to decide two things: first, whether the illness really is cholangitis, using a combination of signs of infection, blood tests showing the bile is not draining, and a scan; and second, how severe it is, graded from I to III. The grade matters because it decides how urgently the blockage needs to be relieved. Antibiotics alone are not enough — the blocked duct has to be drained, usually with a camera test called an ERCP, and the more severe the grade, the sooner that needs to happen. Grade III means it is being done as an emergency alongside intensive care support.

Frequently asked questions

Related calculators

• Tokyo Guidelines — Cholecystitis — TG18 diagnosis and severity grade for acute cholecystitis
• Biliary Pain (Rome IV) — Rome IV — defining biliary-type pain before intervention
• Revised Atlanta Classification — Acute pancreatitis severity — mild, moderately severe, severe
• BISAP Score — Bedside index for severity of pancreatitis
• Glasgow-Imrie Criteria — Acute pancreatitis severity — the PANCREAS criteria
• Functional Pancreatic SOD — Rome IV — pancreatic sphincter of Oddi disorder

References