Histiocytosis in Injecting Drug Users

Summary

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.

Conditions

• Histiocytosis

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

Sponsors & Collaborators

• Tampere University

  collaborator OTHER

• University of Oulu

  collaborator OTHER

• University of Turku

  collaborator OTHER

• University of Helsinki

  collaborator OTHER

• Tampere University Hospital

  lead OTHER

Principal Investigators

• Pasi I Nevalainen, MD, PhD · Senior consultant

Eligibility

Min Age

18 Years

Max Age

70 Years

Sex

ALL

Healthy Volunteers

No

Timeline & Regulatory

Start

2023-05-29

Primary Completion

2030-12-31

Completion

2030-12-31

Countries

• Finland

Study Locations