TG18 Grade II/III acute calculous cholecystitis
INTERNATIONAL SNAPSHOT STUDY · OPTIONAL PROMs

Three pathways for acute cholecystitis

SnapChole follows adults with TG18 Grade II or III acute calculous cholecystitis to understand how initial management and 90-day outcomes vary across centres.

Recruitment: March–August 2027One 90-day local recruitment window · 90-day patient follow-up

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THE FIRST MANAGEMENT DECISION
Explore the study design

Cholecystectomy first, percutaneous drainage first, or antimicrobials alone. SnapChole observes decisions made by the clinical team.

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THE SNAPCHOLE COLLABORATION

Centre enrolment

Centre registration is open. Public totals will appear when available.

Country-level sign-ups
SnapChole country footprintMarkers show centre sign-ups grouped by country, using approximate country locations.

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STUDY POPULATION

Who the study includes

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The snapshot includes consecutive eligible adults with moderate or severe acute calculous cholecystitis, defined by Tokyo Guidelines 2018.

Grade II · Moderate

At least one TG18 Grade II criterion, such as symptoms lasting more than 72 hours, marked local inflammation or a white cell count above 18,000/mm³.

Grade III · Severe

Dysfunction of at least one organ system.

PLANNED ANALYSIS

How initial strategies are compared

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The comparison population

The target-trial emulation compares patients for whom all three strategies were clinically feasible and available at the first management decision.

Treatment over time

The primary analysis uses a 24-hour grace period. Subsequent escalation and other treatment changes are recorded through follow-up.

Snapshot of care

Include consecutive eligible patients over 90 days. Record presentation, treatment, escalation and outcomes through 90-day follow-up.

Patient-reported recovery

Optional GIQLI questionnaires at baseline and 90 days add the patient perspective on symptoms, function and quality of life, with local approval and consent.

Recognition on PubMed

Contributors to recruitment, data collection and validation will be named as Investigators in the SnapChole Collaborative, with the list submitted for PubMed indexing.

Named manuscript authorship follows ICMJE criteria.

Planning your centre’s participation

Register to begin onboarding and receive a confidential summary of your centre’s audit findings after participation. Data collection starts after local requirements and site activation are confirmed.

Your local team
Appoint a local investigator and organise staff for consecutive screening, data entry, 90-day follow-up and validation.
Who completes what
Your team records clinical findings, decisions, care and follow-up. Coordinator-managed fields and derived outcomes are labelled in the CRF.
After registration
The coordinating team reviews your centre’s components and requirements, confirms training and data access, and agrees activation and your 90-day window.
Investigator names
The local investigator keeps a list of contributors and roles, then confirms names with the coordinating team before publication.
YOUR CENTRE STARTER PACK

All the study documents

Download available documents

Study & data collection

Collaborator ManualVersion 1.2 · For information only (not for IRB applications)Word ↓ Centre invitation letter6 Nov 2026 · Study invitation and how to participatePDF ↗
Snapshot protocolRecruitment schedule revised 6 Nov 2026PDF ↗Word ↓
PROMs protocolRecruitment schedule revised 6 Nov 2026PDF ↗Word ↓
Patient case report formsPlanning copy · 6 Nov 2026 · activation version to be confirmedPDF ↗

Participant information & governance

GIQLI participant informationPenn sheet · supplied 6 Nov 2026 · local review requiredWord ↓
IRB / ethics documentsApproval letters will be added as issuedTo follow
Penn data-use agreementNot yet created · pending Penn eIRBPending
Discuss local approvals or data agreements

The CRF is provided for planning while instrument details are finalised; use the confirmed activation version for collection. Each centre must establish its component-specific approvals, consent and data-sharing arrangements.

DATA COLLECTION AT A GLANCE

What your team records

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  1. 1

    Presentation

    Eligibility and TG18 grade
    Frailty and comorbidities
    Observations, labs and imaging

  2. 2

    Initial plan

    Treatment selected and timing
    Clinical feasibility and resources
    Reasons for the decision

  3. 3

    Clinical course

    Procedures and source control
    Escalation and treatment changes
    Hospital episodes and ICU stay

  4. 4

    90-day outcomes

    Survival and days out of hospital
    Readmissions and reinterventions
    Planned interval surgery

90-DAY FOLLOW-UP

Outcomes across the three pathways

The primary outcome for the comparison is days alive and out of hospital through day 90. The study also records mortality, escalation, biliary reinterventions and hospital stay.

The optional PROMs component measures patient-reported recovery at baseline and 90 days.

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Centre context · Service model and available surgical, imaging, interventional and ICU resources.

Optional PROMs · GIQLI at baseline and 90 days, paired locally.

Eligibility, data sharing and analysis

Each centre recruits during one 90-day window within March–August 2027; final 90-day follow-up extends into November 2027.

Adults aged 18 or older with confirmed TG18 Grade II or III acute calculous cholecystitis are eligible. Grade I alone, acalculous disease, isolated duct stones or cholangitis without cholecystitis, primary gallstone pancreatitis and elective chronic biliary presentations are excluded.

Audit submissions and external PROM summaries are aggregate. Separately approved patient-level data will support prespecified statistical analyses, including three-arm target-trial emulation of initial management strategies. Treatment remains selected by the clinical team. The component protocols govern the relevant data flow and consent requirements.

STUDY LEADERSHIP & STEERING GROUP

The SnapChole team

Contact the study team
Principal Investigator

Gary Alan Bass

University of Pennsylvania, Philadelphia, USA

Study Coordinator

Stefano P. B. Cioffi

Niguarda University Hospital, Milan, Italy

Michele Altomare

Niguarda University Hospital, Milan

Stefania Cimbanassi

Niguarda University Hospital, Milan

Lewis J. Kaplan

University of Pennsylvania

Hayato Kurihara

Policlinico di Milano

Laura Kvasnicová

Nemocnice TGM Hodonín, Czechia

Matthew J. Lee

University of Birmingham

Isidro Martínez-Casas

Virgen del Rocío Hospital, Seville

Dane Isenberg

Biostatistics · Villanova University

Nandita Mitra

Biostatistics · University of Pennsylvania

Bring your centre into SnapChole

Register your hospital and local investigator through Penn REDCap.

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