Pattern-based histologic approach in colitis with chronic architectural damage: GIPAD recommendations.
Dig Liver Dis 2026 Jul; 58(7):889-898.

Abstract

Histologic evaluation of colonic biopsies in patients with chronic diarrhea or long-standing colitis is frequently performed in the setting of incomplete clinical, endoscopic, or laboratory information. In this context, overlapping morphologic features across different etiologies often lead to nonspecific or misleading diagnoses, such as "chronic colitis," with potential implications for patient management. To improve diagnostic clarity and clinicopathologic communication, the Italian Group of Digestive Disease Pathology (GIPAD) developed a structured, pattern-based histologic approach for the interpretation and reporting of adult colitis with chronic architectural damage, based on multidisciplinary discussion and critical appraisal of the literature. Distinct histologic patterns are described and correlated with relevant differential diagnoses. Major patterns of colitis with chronic architectural damage are identified, and for each pattern, key morphologic features and principal differential diagnoses-including inflammatory bowel disease and other conditions such as drug-related injury, ischemia, infection, diversion colitis, and immune-mediated disorders-are discussed. A pattern-based histologic approach provides a practical framework for reporting colitis with chronic architectural damage. This strategy narrows differential diagnoses, avoids nonspecific terminology, and supports clinical decision-making, while preserving the primacy of integrated clinicopathologic diagnosis when sufficient information is available.

Authors+Show Affiliations

Reggiani Bonetti LDepartment of Diagnostic, Clinic and Public Health Medicine. Pathological Anatomy Unit. University of Modena and Reggio Emilia, Modena, Italy.
Arpa GDepartment of Molecular Medicine, University of Pavia, Pavia, Italy; Department of Pathology, ASST Santi Paolo e Carlo, Milan, Italy.
Caputo ADepartment of Medicine, Surgery, and Dentistry "Scuola Medica Salernitana", University of Salerno, Baronissi (SA), Italy; Department of Pathology, University Hospital of Salerno, Salerno (SA), Italy. Electronic address: alcaputo@unisa.it.
Grillo FPathology Unit, Department of Surgical Sciences and Integrated Diagnostics (DISC), University of Genoa, Genoa, Italy; IRCCS Azienda Ospedaliera Metropolitana (IRCCS AOM), Ospedale Policlinico San Martino, Genoa, Italy.
Vanoli ADepartment of Molecular Medicine, University of Pavia, Pavia, Italy; SC Anatomia Patologica, Fondazione IRCCS Policlinico San Matteo, Pavia, Italy.
Mastracci LPathology Unit, Department of Surgical Sciences and Integrated Diagnostics (DISC), University of Genoa, Genoa, Italy; IRCCS Azienda Ospedaliera Metropolitana (IRCCS AOM), Ospedale Policlinico San Martino, Genoa, Italy.
Panarese IUOC di Anatomia Patologica, Azienda Ospedaliero Universitaria ``Luigi Vanvitelli'', Napoli, Italy.
Spaggiari PPathology Unit, IRCCS Humanitas Research Hospital, Milano, Italy.
Albarello LPathology Unit, IRCCS Ospedale San Raffaele, Milano, Italy.
Macciomei MCPathology Unit, Department of Oncology and Specialist Medicines, Azienda Ospedaliera San Camillo Forlanini, Roma, Italy.
Pennelli GDepartment of Medicine (DIMED), University of Padua, Padua, Italy.
Angerilli VDepartment of Medicine (DIMED), University of Padua, Padua, Italy; Surgical Pathology Unit, ULSS2 Marca Trevigiana, Treviso, Italy.
Savino LUnit of Anatomic Pathology, SS Annunziata Hospital, ASL2 Abruzzo, Chieti, Italy.
Savarino EVDepartment of Surgery, Oncology and Gastroenterology, University of Padua, Padua, Italy; Gastroenterology Unit, Azienda Ospedale Università Padova, Padua, Italy.
Ribaldone DGDepartment of Medical Sciences, University of Turin, Turin, Italy.
Gafà RDepartment of Translational Medicine, University of Ferrara, Ferrara, Italy; Pathology Unit, Azienda Ospedaliero-Universitaria Ferrara, Ferrara, Italy.
Salviato TPathology Department, Istituto Nazionale Tumori-IRCCS-Fondazione G. Pascale, 80131 Naples, Italy.
Parente PPathology Unit, Azienda Ospedaliero-Universitaria Policlinico Foggia, Foggia, Italy. Electronic address: paolaparente77@gmail.com.
Fassan MDepartment of Medicine (DIMED), University of Padua, Padua, Italy; Veneto Institute of Oncology, IOV-IRCCS, Padua, Italy.
Rosini FPathology Unit, IRCCS Azienda Ospedaliero-Universitaria di Bologna, Bologna, Italy.

Pub Type(s)

Journal Article
Review
Practice Guideline

Language

eng

PubMed ID

42115054