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The Incidence and Predisposing Factors of John Cunningham Virus-Induced Progressive Multifocal Leukoencephalopathy in

Marge Kartau1, Auli Verkkoniemi-Ahola1, Anders Paetau2

  • 1Clinical Neurosciences, Neurology, Helsinki University Hospital and Helsinki University, Finland.

Open Forum Infectious Diseases
|March 1, 2019
PubMed
Abstract

Insights

Progressive multifocal leukoencephalopathy (PML) affects 1.56 per 100,000 people, often linked to hematologic cancers or HIV. Survival rates are poor, highlighting the need for safety screening protocols.

Area of Science:

  • Neurology
  • Infectious Diseases
  • Epidemiology

Background:

  • Progressive multifocal leukoencephalopathy (PML) is a rare, serious demyelinating disease of the central nervous system.
  • Assessing PML prevalence, incidence, and survival is crucial for understanding its impact across medical specialties.

Purpose of the Study:

  • To determine the prevalence, incidence rate (IR), predisposing factors, survival rate, and diagnostic delay of PML.
  • To investigate how PML diagnoses were made in various medical contexts.

Main Methods:

  • A retrospective observational study was conducted from 2004-2016 in Finland.
  • Data were collected from clinical records, laboratory, pathology, radiology, and HIV quality registers.

Main Results:

  • 31 PML cases were identified, with a prevalence of 1.56/100,000 and an IR of 0.12/100,000 person-years.
  • Hematologic malignancies (19 cases) and HIV/AIDS (5 cases) were most common; many patients received chemotherapy or rituximab.
  • The 5-year survival rate was below 10%, with no significant impact from demographic or clinical factors on survival.

Conclusions:

  • PML is frequently associated with predisposing conditions or immunosuppressive therapies.
  • Increased use of immunomodulatory drugs may lead to more PML cases in unrelated diseases.
  • Implementing safety screening for John Cunningham virus (JCV) is vital for preventing new PML cases.
Keywords:
HIVJC virusmonoclonal antibodiesprogressive multifocal leukoencephalopathyrituximab

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