Progressive multifocal leukoencephalopathy secondary to rituximab-induced immunosuppression and the presence of John Cunningham virus: a case report and literature review oleh Deirdre Kelly, MBBCH, Bernadette Monaghan, MBBCH, Eileen McMahon, MBBCH, Geoffrey Watson, MBBCH, Eoin Kavanagh, MBBCH, Killian O'Rourke, MBBCH, John McCaffrey, MBBCH, Desmond Carney, MBBCH