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Published on: October 19, 2014
Progressive multifocal leukoencephalopathy as the presenting feature in a patient with occult low-count monoclonal
Divya Santhanam1, Stephanie Chan1, Chris Nguyen1
1Schulich School of Medicine and Dentistry, Western University, London, Ontario, Canada.
Introduction:
Low Count Monoclonal B-Cell Lymphocytosis (LC-MBL) is a relatively poorly understood entity which has been suggested to be very common in asymptomatic adults and possibly related to infectious complications despite not progressing to CLL.
Methods:
We describe the first case of Progressive Multifocal Leukoencephalopathy (PML) presenting in a 72-year-old man with LC-MBL but no other immunocompromising conditions.
Results:
A diagnosis of PML was confirmed with classic MRI findings in association with a high CSF John Cunningham polyomavirus (JCV) viral load (4.09' 105 copies/mL). An extensive search for underlying immunocompromising conditions only demonstrated LC-MBL representing approximately 4% of total leukocytes (0.2' 109/L).
Discussion:
This is the first report of PML in association with LC-MBL. Careful review of peripheral blood flow cytometry results is necessary to identify this disorder. Further study of the epidemiology and infectious complications of LC-MBL are warranted.
Insights
This study reports the first case of Progressive Multifocal Leukoencephalopathy (PML) in a patient with Low Count Monoclonal B-Cell Lymphocytosis (LC-MBL). This finding highlights the need for further research into LC-MBL and its potential complications.
Area of Science:
- Hematology
- Neurology
- Infectious Diseases
Background:
- Low Count Monoclonal B-Cell Lymphocytosis (LC-MBL) is an understudied condition.
- LC-MBL is common in asymptomatic adults and may be linked to infections.
- It is generally understood not to progress to Chronic Lymphocytic Leukemia (CLL).
Purpose of the Study:
- To report the first case of Progressive Multifocal Leukoencephalopathy (PML) in a patient diagnosed with LC-MBL.
- To investigate potential associations between LC-MBL and opportunistic infections.
Main Methods:
- Case report of a 72-year-old male patient.
- Diagnosis of PML confirmed via MRI and high cerebrospinal fluid (CSF) John Cunningham polyomavirus (JCV) viral load.
- Comprehensive evaluation for other immunocompromising conditions.
Main Results:
- PML was diagnosed in a patient with LC-MBL as the sole identified immunocompromising condition.
- The patient presented with classic MRI findings and a JCV viral load of 4.09 x 10^5 copies/mL.
- LC-MBL constituted approximately 4% of the patient's total leukocytes.
Conclusions:
- This is the inaugural report of PML occurring in association with LC-MBL.
- Peripheral blood flow cytometry is crucial for identifying LC-MBL.
- Further research is essential to understand the epidemiology and infectious risks associated with LC-MBL.
