Late-Onset Neutropenia in Long-Term Clozapine Use and Its Management Utilizing Prophylactic G-CSF

Abstract

This case outlines recurrent neutropenia after fourteen years of successful clozapine use. The patient has a diagnosis of treatment-resistant schizophrenia which has been complicated by sensitivity to side effects of haloperidol and past failure of antipsychotics to manage her symptoms. It was necessary for our patient to follow a complicated treatment path involving close monitoring of blood levels, admissions, the initiation of lithium and the regular use of filgrastim (Neupogen), granulocyte colony stimulating factor (G-CSF). Following a failure of rescue filgrastim to increase her neutrophil levels, a management protocol was designed with input from the on-site hematology team. This protocol involved the use of filgrastim on a regular prophylactic basis. This management plan has worked for the patient who has been able to continue use of clozapine and has not suffered from any neutropenic episodes in over six months.

Clozapine rechallenge or continuation despite neutropenia or agranulocytosis using colony-stimulating factor: A systematic review

“…One case was also reported in two different articles and was therefore only included once in this review ( Meyer et al, 2015 ; Spencer et al, 2012 ). As detailed in Table 1 , 27 articles were case reports or non-consecutive series (total n = 38 cases) ( Broughton et al, 2012 ; Comacchio et al, 2016 ; Conus et al, 2001 ; Elmore et al, 2016 ; Fabre-Bernal et al, 2019 ; Foster et al, 2017 ; Freeman et al, 2016 ; Friedman et al, 2017 ; Gopalakrishnan et al, 2013 ; Gugger and Caley, 2007 ; Hagg et al, 2003 ; Hazewinkel et al, 2013 ; Huguet et al, 2013 ; Joffe et al, 2009 ; Karst and Lister, 2018 ; Khan et al, 2013 ; Majczenko and Stewart, 2008 ; Martina et al, 2019 ; Mathewson and Lindenmayer, 2007 ; Morrow et al, 2020 ; O’Neill et al, 2021 ; Rajagopal et al, 2007 ; Ruiz-Doblado et al, 2020 ; Sengupta and Harvey, 2010 ; Shuman et al, 2021 ; Spencer et al, 2012 ; Sperner-Unterweger et al, 1998 ), while there were only 2 consecutive case series ( n = 15 cases) ( Béchard et al, 2021 ; Silva et al, 2021 ) and 1 retrospective cohort study ( n = 6 cases) ( Meyer et al, 2015 ), for a total of 59 individual cases.…”