Menu
Enrolling by invitation NCT06573671

Histiocytosis in Injecting Drug Users

Observational Histiocytosis

For patients and families

In plain language

An automatic summary of structured registry data. It is an orientation aid, not a substitute for the official protocol or a physician assessment.

What is being studied
The protocol lists: Chitotriosidase, Mass spectrometry, scanning electron microscope with energy-dispersive X-ray spectroscopy, Fluorescence microscopy.
Who it may be relevant to
Registry conditions: Histiocytosis. Basic parameters: 18 years — 70 years · All.
What needs checking
Age, condition and sex are only basic indicators. Prior treatment, laboratory values and other mandatory requirements appear in the eligibility criteria below.
Where it takes place
Finland
Next step
Save the trial, show it to the treating physician, and confirm current recruitment with the study center. Costs, documents and travel →

Overview

The goal of this observational study is to describe a new disease condition of histiocytosis related to injecting drug use, its preconditions, symptoms, signs, findings, and prognosis in a detailed and systematic patient series in one referral center. The main question\[s\] it aims to answer are: * to find specific histologic features in different tissues to help the differential diagnosis from other histiocytoses * to describe the value of chitotriosidase activity to screen this condition * to describe the value of various tissue biopsies in confirming the diagnosis * to describe the nature of polyvinylpyrrolidone accumulation in tissue macrophages by novel special microscopic techniques * to find new tandem mass spectrometry methodology to prove polyvinylpyrrolidone accumulation in macrophages * to show that polyvinylpyrrolidone treatment activates macrophages to histiocytes and causes povidone accumulation within the cells in in vitro experiments * to evaluate the pathology of macrophage activation to histiocytes by transcriptomics The patient history will be collected from the data produced by follow-up of cases followed up in a single center. A subgroup of participants will be given an opportunity to sign informed consent to give access to/donate blood and tissue samples to search for techniques to prove polyvinylpyrrolidone storage within histiocytes, and to search for transcriptomics signal(s) in histiocytes. Researchers will compare blood and tissue samples from the biobank as controls.

Detailed description

Comprehensive patient data (disease history, findings, complications, laboratory findings, histopathology, and imaging) will be obtained from patient records of a single university hospital. Coded histiocytosis-positive tissue samples will be compared to biobank samples from corresponding tissues from healthy and other histiocytosis tissue samples to show polyvinylpyrrolidone storage with novel methodologies.

In addition, if a study participant who is followed up clinically, signs informed consent, monocytes are separated from a blood sample, differentiated to macrophages, and exposed to polyvinylpyrrolidone. Various novel methods will be utilized to explore polyvinylpyrrolidone within histiocytes.

Interventions

  • Diagnostic test Chitotriosidase
    The amount of patients with increased chitotriosidase, and the extent of elevation of chitotriosidase
  • Diagnostic test Mass spectrometry
    to show polyvinylpyrrolidone presence in histiocytes of injecting drug users compared to controls
  • Diagnostic test scanning electron microscope with energy-dispersive X-ray spectroscopy
    to show polyvinylpyrrolidone presence in histiocytes of injecting drug users compared to controls
  • Diagnostic test Fluorescence microscopy
    to show polyvinylpyrrolidone presence in histiocytes of injecting drug users compared to controls
  • Diagnostic test Transcriptomics
    To describe pathologic signals of polyvinylpyrrolidone-exposed in vitro histiocytes of injecting drug users compared to control samples

Primary outcome measures

  • Frequency of disease manifestations [Time frame: 10 years]
Secondary outcome measures (6)
  • Frequency of elevated chitotriosidase activity [Time frame: 10 years]
  • Mortality [Time frame: 10 years]
  • Microscopic fluorescence positive tissue [Time frame: 10 years]
  • Scanning electron microscope with energy-dispersive X-ray spectroscopy [Time frame: 10 years]
  • Pyrolysis mass spectrometry [Time frame: 10 years]
  • Transcriptomics analysis [Time frame: 10 years]

Eligibility criteria

Inclusion criteria

  • All identified adult patients in our records with a history of injecting drug use by dissolving tablets containing polyvinylpyrrolidone and (suspected) PVP-histiocytosis

Exclusion criteria

  • Other histiocytosis diagnosed by tissue samples and clinical information

Criteria are shown verbatim from the registry (in English). Final eligibility is always assessed by the study center.

Study design

Observational model
Cohort

Study locations

Finland · 1 center
  • Tampere University Hospital — Tampere

Identifiers

NCT: NCT06573671 · R20105

Primary sources (government registries)

View this study on ClinicalTrials.gov ↗