Rapid Cognitive Decline in a Patient With Chronic Lymphocytic Leukaemia

A Case Report

James Forryan; Jun Yong


J Med Case Reports. 2020;14(39) 

In This Article


In conclusion, this case report aims to highlight the association between B-cell-depleting therapy and PML, particularly in the setting of haematological malignancy and with lesser used therapies such as ofatumumab. PML should take its place in any differential list for a patient receiving B-cell-depleting mAbs who presents with new neurology and cognitive defects as in our case. Additionally, we aim to bring attention to the mechanisms by which B-cell-depleting therapy can create an immune environment in which the JCV can become pathogenic; this raises the question as to how we can treat autoimmune and lymphoproliferative disease with B-cell-depleting therapy whilst mitigating the resultant increased risk of PML. Knowing the risk of PML with B-cell-depleting therapy, expediting research into JCV vaccination and pharmacological treatment, with concomitant development of evidence-based risk stratification algorithms and predictive biomarkers, seems the best way of reducing this risk at present. Finally, whilst rituximab's effects on B-cell populations has been extensively studied (e.g., the shift from an effector B-cell pool to one made up of naïve B-cells and plasma cells), the same cannot be said of ofatumumab; clarification as to the phenotype of post-treatment B-cell populations with other B-cell-depleting mAbs could be revealing in terms of their risk-profile for PML compared to rituximab.