Epidemiology, Diagnosis, Medical Care and Prognosis of Tubulointerstitial Nephritis: Results of a Multicenter Retrospective Cohort Study (NETI-MULTI)

Tubulointerstitial nephritis (TIN), diagnosed on kidney biopsy, represents a common cause of kidney failure. The etiologies are multiple but the diagnosis of the causative disease is sometimes difficult and the treatment is not completely codified.

The research focuses on the characterization of TIN on the etiological, clinical, biological, therapeutic and prognostic levels in order to improve patient care.

For this purpose, kidney biopsies performed for the diagnosis, kept in a biological collection within the biological resource platforms of the Necker-Enfants Malades hospital and the Georges Pompidou hospital will be centrally reviewed, blinded to the final diagnosis.

Study Overview

• Status: Completed
• Conditions: Nephritis, Interstitial
• Intervention / Treatment: Other: Rereading of biopsies; Other: Collection of data from the patient's medical file

Detailed Description

Tubulointerstitial nephritis (TIN) is defined as a diverse set of renal pathologies caused by a primary lesion of the interstitial compartment, which most often extends to the associated tubular structures. Renal histology establishes the diagnosis by objectifying different types of lesions associated to varying degrees depending on the etiology and clinical course. These lesions are: an interstitial inflammatory infiltrate whose nature is largely dependent on the etiopathogenic mechanisms of the lesion, diffuse or multifocal interstitial fibrosis, tubular epithelial lesions in the form of tubulitis and/or tubular atrophy.

Research focuses on the characterization of TIN on the etiological, clinical, biological, therapeutic and prognostic levels in order to try to improve patient care. For this:

• 1st step: native kidney biopsies performed to establish the diagnosis and kept in a biological collection within the biological resource platforms of the Necker-Enfants Malades hospital and the Georges Pompidou hospital will be centrally reviewed The review will be performed at the Pathology department of Necker hospital, blinded to the final diagnosis for selection of the biopsies that will be included in the study. Included biopsies will be those with tubulointerstitial nephritis retained as the main cause of renal dysfunction after etiological investigation
• 2nd step: collection of clinical and biological data regarding the diagnosis, management and prognosis
• 3rd step: statistical analysis of the data and consolidation of the results.

• Study Type: Observational
• Enrollment (Actual): 224

Contacts and Locations

Study Locations

• France
  • Paris, France, 75015
    • Hôpital Européen Georges Pompidou
  • Paris, France, 75020
    • Hopital Tenon
  • Paris, France, 75015
    • Hôpital Necker-Enfants Malades

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Adult; Older Adult
• Accepts Healthy Volunteers: No

• Sampling Method: Non-Probability Sample

Study Population

Adult patients with renal dysfunction whose main cause retained after etiological investigation is tubulointerstitial nephritis and treated at the Necker-Enfants Malades hospital or at the Georges Pompidou European hospital.

Description

Inclusion Criteria:

• Adult patients who do not object to the use of their medical data and samples for this research
• With a biopsy of the care on native kidney and subject to a biological collection, finding tubulointerstitial nephritis in the foreground and retained as the main cause of renal dysfunction after etiological investigation.

• Signs of histological activity of the NTI objectified during the centralized rereading and defined by:

  • An inflammation of more than 10% of the surface of the entire cortical parenchyma (fibrous and non-fibrous) or a ti score > or = 1 according to the Banff classification
  • AND/OR the presence of at least one granuloma on the biopsy

Exclusion Criteria:

• No access to medical records for data collection, or insufficient clinical data
• Follow-up less than 3 months
• Histological lesions of the tubulointerstitial sector but related to a hematological, urological, genetic etiology or the direct tubular toxicity of a drug

Study Plan

How is the study designed?

Number of groups / cohorts

1

Cohorts and Interventions

Group / Cohort

Intervention / Treatment

Patients; Patients whose biopsy of the care revealed tubulointerstitial nephritis in the foreground and retained as the main cause of renal dysfunction after etiological investigation. The biopsies concerned were carried out between 01/01/2010 and 31/12/2019. The clinical follow-up data of the patients from whom the biopsies were taken will be collected until the date of the last follow-up (before 31/12/2021).

Other: Rereading of biopsies; Rereading of biopsies, blinded to the final diagnosis, by a pathologist specializing in nephropathology. This review includes: an optical microscopy study on a fragment fixed with routine staining, an optical microscopy study on a frozen fragment, an immunohistochemical study on a frozen fragment if available.; Other: Collection of data from the patient's medical file; Collection of data from the patient's medical file. The clinical data of the care of patients at whom the biopsies belong will be analyzed until the date of the patient's last follow-up (before 12/31/2021).

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Evolution of glomerular filtration rate and renal survival	Evolution of glomerular filtration rate and renal survival (defined as the persistence of sufficient renal function not requiring the use of a replacement technique) over time and according to etiology.	Time 0

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Significant association between renal prognosis with specific predictive factors	Significant association between renal prognosis, defined by glomerular filtration rate and/or end-stage renal dysfunction with specific predictive factors. Description of Clinical (age, sex, etiology, high blood pressure, diabetes, early extra-renal purification, AKI stage), biological (peak creatinine, hemoglobin, calcemia, proteinuria, hematuria) and histological factors (interstitial infiltrate, tubulitis, presence of granulomas, fibrosis).	Time 0
Response to corticosteroid therapy	Evolution of glomerular filtration rate and renal survival over time as a function of corticosteroid treatment.	Time 0
Association between response to corticosteroid therapy and some histological criteria	Association between response to corticosteroid therapy and some histological criteria. Description of histological criteria : interstitial infiltrate, tubulitis, presence of granulomas, fibrosis.	Time 0
Evaluate the contribution of histological analysis in etiological diagnosis	Performance of pathologist review in establishing blind histological diagnosis.	Time 0

Collaborators and Investigators

• Sponsor: Assistance Publique - Hôpitaux de Paris
• Collaborators: URC-CIC Paris Descartes Necker Cochin
• Investigators: Principal Investigator: Marion Rabant, M.D., PhD, Assistance Publique - Hôpitaux de Paris

Study record dates

Study Major Dates

• Study Start (Actual): March 17, 2025
• Primary Completion (Actual): December 15, 2025
• Study Completion (Actual): December 15, 2025

Study Registration Dates

• First Submitted: October 17, 2024
• First Submitted That Met QC Criteria: October 17, 2024
• First Posted (Actual): October 21, 2024

Study Record Updates

• Last Update Posted (Actual): April 3, 2026
• Last Update Submitted That Met QC Criteria: March 30, 2026
• Last Verified: September 1, 2025

More Information

Terms related to this study

• Keywords: Tubulointerstitial nephritis (TIN)
• Additional Relevant MeSH Terms: Urogenital Diseases; Male Urogenital Diseases; Kidney Diseases; Urologic Diseases; Female Urogenital Diseases; Female Urogenital Diseases and Pregnancy Complications; Nephritis; Nephritis, Interstitial
• Other Study ID Numbers: APHP240673

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: NO

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No
• product manufactured in and exported from the U.S.: No