Treatment of severe clozapine-induced neutropenia with granulocyte colony-stimulating factor (G-CSF). Remission despite continuous treatment with clozapine

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

OBJECTIVES

Rechallenge/continuation of clozapine in association with colony-stimulating factors (CSFs) following neutropenia/agranulocytosis has been reported, but many questions remain unanswered about efficacy and safety. This systematic review aims to assess the efficacy and safety of rechallenging/continuing clozapine in patients following neutropenia/agranulocytosis using CSFs.

METHODS

MEDLINE, Embase, PsycInfo, and Web of Science databases were searched from inception date to July 31, 2022. Articles screening and data extraction were realized independently by two reviewers, according to Preferred Reporting Items for Systematic reviews and Meta-Analyses (PRISMA) 2020 systematic review guidance. Included articles had to report on at least one case where clozapine was rechallenged/continued using CSFs despite previous neutropenia/agranulocytosis.

RESULTS

Eight hundred forty articles were retrieved; 34 articles met the inclusion criteria, totaling 59 individual cases. Clozapine was successfully rechallenged/continued in 76% of patients for an average follow-up period of 1.9 years. There was a trend toward better efficacy reported in case reports/series, compared with consecutive case series (overall success rates of 84% and 60%, respectively, p-value = 0.065). Two administration strategies were identified, "as-needed" and prophylactic, both yielding similar success rates (81% and 80%, respectively). Only mild and transient adverse events were documented.

CONCLUSIONS

Although limited by the relatively small number of published cases, factors such as time of onset to first neutropenia and severity of the episode did not seem to impact the outcome of a subsequent clozapine rechallenge using CSFs. While the efficacy of this strategy remains to be further adequately evaluated in more rigorous study designs, its long-term innocuity warrants considering its use more proactively in the management of clozapine hematological adverse events as to maintain this treatment for as many individuals as possible.

Clozapine re-challenge and initiation following neutropenia: a review and case series of 14 patients in a high-secure forensic hospital

OBJECTIVE

Clozapine remains the most effective intervention for treatment resistant schizophrenia; however, its use is prohibited following neutropenias. We review neutrophil biology as applied to clozapine and describe the strategies to initiate clozapine following neutropenia used in a case series of 14 consecutive patients rechallenged in a United Kingdom (UK) high-secure psychiatric hospital. We examine outcomes including the use of seclusion and transfer.

METHODS

A case series of 14 male patients with treatment resistant schizophrenia treated with clozapine despite previous episodes of neutropenia between 2006 and 2015 is presented. Data were collected during 2015 and 2019. Using this routinely collected clinical data, we describe the patient characteristics, causes of neutropenia, the strategies used for rechallenging with clozapine and clinical outcomes.

RESULTS

Previous neutropenias were the result of benign ethnic neutropenia, clozapine, other medications and autoimmune-related. Our risk mitigation strategies included: granulocyte-colony stimulating factor (G-CSF), lithium and watch-and-wait. There were no serious adverse events; at follow up half of the patient's had improved sufficiently to transfer them to conditions of lesser security. There were dramatic reductions in the use of seclusion.

CONCLUSION

Even in this extreme group, clozapine can be safely and effectively re/initiated following neutropenias, resulting in marked benefits for patients. This requires careful planning based on an understanding of neutrophil biology and the aetiology of the specific episode of neutropenia.

Clozapine rechallenge and initiation despite neutropenia- a practical, step-by-step guide

Clozapine remains the only drug treatment likely to benefit patients with treatment resistant schizophrenia. Its use is complicated by an increased risk of neutropenia and so there are stringent monitoring requirements and restrictions in those with previous neutropenia from any cause or from clozapine in particular. Despite these difficulties clozapine may yet be used following neutropenia, albeit with caution. Having had involvement with 14 cases of clozapine use in these circumstances we set out our approach to the assessment of risks and benefits, risk mitigation and monitoring with a practical guide.

Clozapine Rechallenge After Major Adverse Effects: Clinical Guidelines Based on 259 Cases

BACKGROUND

Clozapine is widely prescribed for treatment-refractory schizophrenia, but its use is limited by many potentially life-threatening adverse effects. The risk of rechallenge after these complications has never been comprehensively assessed in controlled studies. Thus, clinical guidelines must rely on the published case reports. The number of such reports is likely to increase over time, and updated analyses of larger samples are needed, as they may lead to changes in clinical guidelines.

STUDY QUESTIONS

How safe is the clozapine rechallenge after life-threatening adverse effects?

STUDY DESIGN

The published case reports of clozapine rechallenge were identified in a MEDLINE search. We added 121 cases reported from 2012 through 2017 to the 138 cases reported from 1972 through 2011 analyzed by us in a previous publication. The 95% confidence intervals (CIs) of the successful rechallenge rate were calculated for each adverse effect with at least 5 published case reports. The rechallenge was considered a valid clinical option when the lower end of the CI range was at least 50%.

RESULTS

A successful outcome was documented in 128/203 patients rechallenged after neutropenia (63.0%, CI, 56.0%-69.6%), 3/17 after agranulocytosis (17.7%, CI, 4.7%-44.2%), 11/17 after myocarditis (64.7%, CI, 38.6%-84.7%), and 7/7 after neuroleptic malignant syndrome (100%, CI, 56.1%-100%). Among the 15 patients with other clozapine-induced adverse effects, the rechallenge was successful in those with eosinophilia, cardiac complications other than myocarditis (QTc prolongation, pericarditis, cardiomyopathy, and atrial flutter), and gastrointestinal hypomotility. The rechallenge failed in patients who had developed pancreatitis or renal insufficiency.

CONCLUSION

Clozapine rechallenge is a reasonable clinical option after return to baseline for patients who had developed neutropenia and neuroleptic malignant syndrome, but not after agranulocytosis or myocarditis. Data are insufficient to formulate rechallenge guidelines for any other clozapine-related adverse effects.

Re-titration rates after clozapine-induced neutropenia or agranulocytosis: A case report and literature review

Clozapine-induced neutropenia occurs in 3-5% of individuals treated with clozapine. Current US guidelines require interruption of clozapine when the absolute neutrophil count (ANC) drops below 1000 cells/mm3. There is minimal available guidance for what dosing schedule to use when restarting clozapine after an episode of neutropenia. Here, we present a case of a 50-year-old Caucasian female with a history of schizoaffective disorder who was successfully rechallenged on clozapine one month after developing clozapine-induced neutropenia (ANC 600 cells/mm3). To understand published re-titration rates of clozapine after neutropenia, we conducted a literature review using a using the PubMed database and found only seven case reports that unambiguously reported a clozapine dosing schedule during re-challenge. All were successful except one, a case of clozapine rechallenge after agranulocytosis. Including this case presentation, six out of eight cases restarted clozapine more cautiously than recommended by the US guidelines for a new clozapine initiation. We cannot comment what role a slower or more rapid titration plays in a successful rechallenge after neutropenia with the available evidence. We encourage researchers to publish their dosing schedule in detail after an episode of neutropenia or agranulocytosis.

The Use of Granulocyte Colony-Stimulating Factor in Clozapine Rechallenge: A Systematic Review

PURPOSE/BACKGROUND

Clozapine is associated with hematological abnormalities, with neutropenia and agranulocytosis of most concern. Granulocyte colony-stimulating factor (G-CSF) has been used to support clozapine rechallenge after neutropenia with the aim of maintaining the neutrophil count. This study aims to explore the practice, use, safety, and efficacy of G-CSF in this context.

METHODS/PROCEDURES

We conducted a systematic review to identify all studies investigating or describing G-CSF as a prophylaxis to enable continued clozapine treatment during a rechallenge.

FINDINGS/RESULTS

We identified 32 reports of patients who received G-CSF either regularly (n = 23) or as required (n = 9) to support clozapine rechallenge after an episode of neutropenia necessitating discontinuation of clozapine. Seventy-five percent (n = 24) of published cases remained on clozapine with the use of continual prophylactic G-CSF or after single G-CSF administrations (n = 8). Seventy percent (n = 16) of patients in receipt of continual prophylactic G-CSF were successfully maintained on clozapine. However, 1 of the 3 episodes of rechallenge in those with a history of severe agranulocytosis (absolute neutrophil count <0.1 × 10/L) had a recurrence of agranulocytosis at week 9.

IMPLICATIONS/CONCLUSIONS

Our findings suggest that G-CSF can sometimes be safely used to support the maintenance of normal neutrophil counts and clozapine use after neutropenia. Publication bias is an important limitation, however. Also, few reports clearly documented the presence or absence of an independent nonclozapine cause of the index neutropenia, which may have increased success rates. Furthermore, adverse events were not systematically recorded. Prospective studies are needed to determine safety because if agranulocytosis occurs on clozapine while supported by G-CSF, there is no obvious alternate rescue therapy to promote granulopoiesis. From the available data, it is not possible to recommend this course of action for someone with a true clozapine agranulocytosis.

Use of granulocyte-colony stimulating factor to prevent recurrent clozapine-induced neutropenia on drug rechallenge: A systematic review of the literature and clinical recommendations

BACKGROUND

Clozapine is the most effective medication for treatment-refractory schizophrenia; however, its use is contraindicated in people who have had previous clozapine-induced neutropenia. Co-prescription of granulocyte-colony stimulating factor may prevent recurrent neutropenia and allow continuation or rechallenge of clozapine.

OBJECTIVE AND METHODS

Systematic review of literature reporting the use of granulocyte-colony stimulating factor to allow rechallenge or continuation of clozapine in people with previous episodes of clozapine-induced neutropenia. The efficacy of granulocyte-colony stimulating factor and predictors of successful rechallenge will be determined to elucidate whether evidence-based recommendations can be made regarding the use of granulocyte-colony stimulating factor in this context.

RESULTS

A total of 17 articles were identified that reported on clozapine rechallenge with granulocyte-colony stimulating factor support. In all, 76% of cases were able to continue clozapine at median follow-up of 12 months. There were no clear clinical or laboratory predictors of successful rechallenge; however, initial neutropenia was more severe in successful cases compared to unsuccessful cases. Cases co-prescribed lithium had lower success rates of rechallenge (60%) compared to those who were not prescribed lithium (81%). The most commonly reported rechallenge strategy was use of filgrastim 150-480 µg between daily to three times a week. There were no medication-specific side effects of granulocyte-colony stimulating factor reported apart from euphoria in one case. Three cases who failed granulocyte-colony stimulating factor had bacterial infection at time of recurrent neutropenia. No deaths were reported.

CONCLUSION

Preliminary data suggest granulocyte-colony stimulating factor is safe and effective in facilitating rechallenge with clozapine. Clinical recommendations for use are discussed.

Lithium carbonate as a treatment for paliperidone extended-release-induced leukopenia and neutropenia in a patient with schizoaffective disorder; a case report

BACKGROUND

Antipsychotic drug treatment can potentially lead to adverse events such as leukopenia and neutropenia. Although these events are rare, they represent serious and life-threatening hematological side effects.

CASE PRESENTATION

We present a case study of a patient with schizoaffective disorder in a 50-year-old woman. We report a case of paliperidone extended-release (ER)-induced leukopenia and neutropenia in a female patient with schizoaffective disorder. Initiating lithium carbonate treatment and decreasing the dose of valproic acid improved the observed leukopenia and neutropenia. This treatment did not influence psychotic symptoms.

CONCLUSION

The combination of paliperidone ER and valproic acid induces increased paliperidone ER plasma levels. Lithium carbonate was successfully used to treat paliperidone ER-induced leukopenia and neutropenia.

Clozapine-Induced Late Agranulocytosis and Severe Neutropenia Complicated with Streptococcus pneumonia, Venous Thromboembolism, and Allergic Vasculitis in Treatment-Resistant Female Psychosis

Clozapine is a second-generation antipsychotic agent from the benzodiazepine group indicated for treatment-resistant schizophrenia and other psychotic conditions. Using clozapine earlier on once a case appears to be refractory limits both social and personal morbidity of chronic psychosis. However treatment with second-generation antipsychotics is often complicated by adverse effects. We present a case of a 33-year-old Caucasian woman with a 25-year history of refractory psychotic mania after switching to a 2-year clozapine therapy. She presented clozapine-induced absolute neutropenia, agranulocytosis, which were complicated by Streptococcus pneumonia and sepsis. Clozapine-induced thromboembolism of the common femoral and right proximal iliac vein, as well as allergic vasculitis, was diagnosed. She achieved full remission on granulocyte-colony stimulating factor and specific antibiotic treatment. Early detection of severe clozapine-induced absolute neutropenia and agranulocytosis enabled the effective treatment of two among its most severe complications. Additional evidence to the previously reported possible causal relation between clozapine and venous thromboembolism is offered. Finally, clozapine-induced allergic vasculitis is confirmed as a late adverse effect of clozapine therapy.

Clozapine treatment of refractory schizophrenia during essential chemotherapy: a case study and mini review of a clinical dilemma

BACKGROUND

Clozapine remains the antipsychotic of choice for refractory schizophrenia. Given the particular side effects of clozapine including neutropenia and myelosuppression, safety and efficacy of add-on chemotherapy for patients who are already under clozapine treatment remain unknown.

OBJECTIVE

We present evidence from a patient with a diagnosis of refractory schizophrenia on clozapine medication, who required essential chemotherapy for chronic lymphocytic leukemia (CLL). We have also reviewed literature regarding this challenging clinical dilemma.

METHOD

We report details about a patient with treatment-resistant schizophrenia who was given chemotherapy (fludarabine, cyclophosphamide and rituximab) for CLL in the course of concomitant treatment with clozapine and granulocyte-colony stimulating factor (G-CSFs). In addition, we have reviewed literature using the PUBMED data base.

RESULTS

Current evidence remains insufficient to provide authoritative guide to clinicians regarding the efficacy and safety of the combined use of clozapine and chemotherapy. However, general conclusion from our case and of the published evidence is that a combination of clozapine use and chemotherapeutic agents do not cause additional hematological worsening with no decreasing efficacy concerns raised.

CONCLUSION

Continuing with clozapine in the course of chemotherapy may be relatively safer for patients who responded well to clozapine concomitant with G-CSF treatment.

Continuing clozapine with granulocyte colony-stimulating factor in patients with neutropenia

BACKGROUND

The current guidelines dictate that clozapine should be stopped following the emergence of neutropenia. Various alternative approaches have been tried in the past, among them one rarely used alternative being to continue treatment with clozapine with coprescription of granulocyte colony-stimulating factor (G-CSF).

AIM AND METHOD

In this case series we aim to describe the treatment and progress of a number of patients in a secure psychiatric hospital in the UK. These patients were restarted on clozapine in combination with G-CSF, in spite of previous neutropenia associated with clozapine treatment.

DISCUSSION AND CONCLUSION

We hope that this case series will raise the profile of a potentially effective alternative to discontinuing clozapine after neutropenia.

Add-on filgrastim during clozapine rechallenge unsuccessful in preventing agranulocytosis

Granulocyte colony-stimulating factor agents such as filgrastim can be administered in order to reduce the duration of clozapine-induced agranulocytosis. Successful long-term combination treatment with filgrastim and clozapine in patients with previous clozapine-induced agranulocytosis has been described in several cases. We describe a patient with schizophrenia who developed agranulocytosis during treatment with clozapine and who did not respond to other antipsychotics. Add-on treatment with filgrastim during a clozapine rechallenge did not prevent the reoccurrence of agranulocytosis, and clozapine treatment had to be discontinued. Our case suggests that add-on filgrastim is a therapeutic option when clozapine is rechallenged, but physicians should be aware of the potential dangers especially severe clozapine-induced agranulocytosis.

Clozapine: key discussion points for prescribers

Clozapine is the most effective antipsychotic medication for treatment-refractory schizophrenia and is also approved for suicidality in schizophrenia patients. However, it can cause significant medical morbidity and requires intensive medical monitoring once prescribed. Perhaps due to lack of familiarity with its use, it is underused in clinical practice and its initiation often delayed. This article reviews the literature on clozapine in order to measure its potential effectiveness against its adverse effects and ultimately aims to serve as a useful summary for clinicians in their everyday prescribing.

When can patients with potentially life-threatening adverse effects be rechallenged with clozapine? A systematic review of the published literature

BACKGROUND

Clozapine is widely prescribed for treatment refractory patients with schizophrenia, but its use is limited by potentially life threatening adverse effects. Rechallenge after these complications has been occasionally attempted in patients with severe psychotic symptoms.

OBJECTIVE

To review the outcome of clozapine rechallenge after potentially life threatening adverse effects.

METHODS

Electronic, all-language, literature search (1972-2011) followed by demographic and clinical data extraction. The outcome of rechallenge was considered favorable when the lower bound of the 95% confidence interval (CI) of the proportion of patients who could continue clozapine was >50%.

RESULTS

Altogether, 138 patients (mean age: 36.3years, 65.7% male, 57.6% Caucasian, virtually all with schizophrenia spectrum diagnosis) underwent clozapine rechallenge after developing neutropenia (n=112), agranulocytosis (n=15), neuroleptic malignant syndrome (NMS) (n=5), myocarditis (n=4), pericarditis (n=1) and lupus erythematosus (n=1). Rechallenge strategies were heterogeneous and not systematically evaluated. Clozapine rechallenge was successful in 78/112 patients (69.6%, CI: 60.6-77.4) after neutropenia, 3/15 (20%, CI: 7.1-45.2) after agranulocytosis, 5/5 (100%, CI: 56-100) after NMS, 3/4 (75%, CI: 30-95) after myocarditis, 1/1 after pericarditis, and 0/1 after clozapine-induced lupus. Successfully rechallenged patients were followed for 16-96weeks. None of the rechallenged patients died.

CONCLUSIONS

Although controlled studies are clearly needed, using a priori, confidence interval-based criteria, case reports/series suggest that in refractory patients who benefited from clozapine, careful rechallenge can be considered after neutropenia and NMS, but not after agranulocytosis and myocarditis.

Lithium, trifluperazine and idiopathic leucopenia: Author and reviewer perspectives on how to write a good case report

BACKGROUND

The Indian Journal of Psychiatry receives many reports which, despite obvious academic worth, are too poorly written to be publishable. Such submissions tax manuscript reviewers and increase the editorial office workload without benefiting the authors with a publication.

METHODS

We describe an authentic and previously unpublished case of idiopathic leucopenia and psychosis. Leucocyte levels in this patient dropped upon challenge with different atypical antipsychotic drugs. Lithium pretreatment, however, permitted the safe and successful use of trifluperazine. Readers are invited to use a roughly-prepared version of the case report to draft a submission-worthy manuscript.

RESULTS

Two versions of the manuscript are presented. The first version is generally satisfactory but will trigger several queries during peer review; these queries are indicated. The second version would be considered acceptable by most reviewers.

CONCLUSIONS

Readers who work through the exercise provided in this article will better understand how authors should prepare their report and how reviewers may scrutinize their manuscript.

Idiosyncratic drug-induced agranulocytosis: possible mechanisms and management

The incidence of drug-induced neutropenia has not changed in the western hemisphere over the last 30 years. Yet, the drug panorama has changed considerably. This implies that host factors may play an intriguing role for this idiosyncratic reaction. The knowledge as to mechanisms for the reaction has advanced with emerging understanding of neutropoiesis and immune regulation. Nonetheless, it is still remarkably difficult to pinpoint why and how a drug causes this unexpected, severe adverse event in a patient. Patient characteristics, e.g. genetics, appear to be keys for better understanding, predictions and prevention. Am. J. Hematol. 2009. (c) 2009 Wiley-Liss, Inc.

Failure of filgrastim to prevent severe clozapine-induced agranulocytosis

Although a highly effective medication, the usage of clozapine is limited mostly by its 2.7% incidence of neutropenia. It is often a treatment of last resort for patients with severe psychiatric illnesses, and therefore often the only medication to which a patient has responded. There has thus been a great deal of interest in ways to continue the medication in spite of emergent blood dyscrasias. There have been several reports documenting the successful continuation of clozapine in spite of neutropenia by adding granulocyte colony-stimulating factors such as filgrastim. This strategy was unsuccessful for a 63-year-old man, resulting in severe, prolonged agranulocytosis. Although a promising strategy for such refractory patients, its inherent dangers should not be underestimated.

Clozapine-induced leukopenia successfully treated with lithium

PURPOSE

A case of clozapine-induced leukopenia successfully treated with lithium is reported.

SUMMARY

A 55-year-old man with paranoid schizophrenia who had been stable on clozapine for more than 10 years was admitted to an inpatient behavioral health unit with leukopenia associated with clozapine use. This patient's history was significant for four previous hospitalizations for psychiatric issues, none of which occurred while he was using clozapine. On admission, the patient's clozapine was discontinued and he was started on olanzapine. On hospital day 4, his white blood cell (WBC) count had risen to 3400/mm(3) and clozapine was resumed due to increasing auditory hallucinations and suicidal ideation. On hospital day 5, his WBC count decreased to 2900/mm(3) and clozapine was again stopped. The patient was given lithium carbonate 300 mg at bedtime, and olanzapine was discontinued. The next day, clozapine was restarted at 12.5 mg daily at bedtime. On hospital day 11, his WBC count had risen to 5400/mm(3). The patient was discharged on clozapine 25 mg at bedtime, with a WBC count of 3400/mm(3). The patient has not been rehospitalized and has not had significant changes in his WBC count or absolute neutrophil count (ANC) for more than 14 months.

CONCLUSION

A 55-year-old man with schizophrenia developed clozapine- induced leukopenia after more than 10 years of treatment. Lithium was used to stimulate leukocyte production, and clozapine was restarted successfully. The patient was maintained on clozapine and lithium without significant changes in his WBC count or ANC.

Restarting clozapine after neutropenia: evaluating the possibilities and practicalities

Clozapine remains the antipsychotic of choice for refractory schizophrenia despite its propensity for serious blood disorders. When neutropenia or agranulocytosis occur in people taking clozapine, cessation of treatment is mandated and relapse often results. Because such patients are usually unresponsive to other antipsychotics, many clinicians consider restarting clozapine, despite the risks involved. However, the risks of clozapine rechallenge vary according to the cause and nature of the blood dyscrasia. Neutropenia can arise because of factors unrelated or indirectly related to clozapine treatment. These include benign ethnic neutropenia, concomitant drug therapy, co-existing medical conditions and drug interactions. In such cases, clozapine may be restarted if non-clozapine causes of neutropenia are identified and eliminated, although concurrent treatment with lithium (to induce leukocytosis) is sometimes necessary. Close monitoring of the patient is essential because it is rarely possible to completely rule out the contribution of clozapine to the blood dyscrasia and because lithium does not protect against clozapine-related agranulocytosis. In cases of clozapine-induced neutropenia (as distinct from agranulocytosis, which may have a different pathology) rechallenge may also be considered and, again, lithium co-therapy may be required. Where clozapine is clearly the cause of agranulocytosis, rechallenge should not be considered or undertaken unless there are very exceptional circumstances (severe and prolonged relapse following clozapine discontinuation). In these cases, re-exposure to clozapine may rarely be attempted where there are facilities for very close and frequent monitoring. Granulocyte colony-stimulating factor is likely to be required as co-therapy, given the very high likelihood of recurrence. Uncertainty over the likely cause of blood dyscrasia in people taking clozapine, coupled with uncertainty over the mechanism by which clozapine causes both neutropenia and agranulocytosis, makes any attempt to restart clozapine a high-risk venture requiring the utmost caution.

Monitoring the safe use of clozapine: a consensus view from Victoria, Australia

Clozapine is an important antipsychotic agent that has a unique profile of clinical benefits, but that has also been associated with several serious and potentially life-threatening safety concerns. In order to minimise the impact of haematological adverse events, health professionals treating patients with clozapine are currently required to register their patients on a centrally administered data network and to conform to strict protocols. The consensus statement documented in this article extends existing protocols by recommending monitoring of patients treated with clozapine for additional adverse effects during treatment. This consensus statement reflects the current practice at five major public psychiatric hospitals in Victoria, Australia, for the monitoring and management of clozapine-related adverse events, and has been implemented at these sites because of emerging safety concerns associating clozapine with cardiovascular and metabolic adverse effects.

Prevention of clozapine-induced granulocytopenia/agranulocytosis with granulocyte-colony stimulating factor (G-CSF) in an intellectually disabled patient with schizophrenia

BACKGROUND

While clozapine is an effective treatment for refractory schizophrenia, its use is limited by haematological side effects. Treatment options that allow continued prescription of clozapine by tackling these side effects will greatly aid patients for whom this medication is all too often their only hope of recovery.

METHOD

In this case report, we describe what we believe are two 'firsts' in the clozapine literature: the use of granulocyte-colony stimulating factor on a prophylactic basis in an intellectually disabled patient receiving clozapine for refractory schizophrenia.

RESULT

Treatment with granulocyte-colony stimulating factor prevented discontinuation of clozapine, enabling our intellectually disabled patient's recovery from a schizophrenic illness.

Reviewing the use of antipsychotic drugs in people with intellectual disability

INTRODUCTION

Antipsychotics are the most widely prescribed drugs in people with intellectual disability even if schizophrenia and other psychotic disorders do not affect more than 3% of such population. Many authors outline the lack of studies on the efficacy of antipsychotics on schizophrenia or other psychotic disorders in people with intellectual disability.

MATERIALS AND METHODS

The aim of the present study is to review all evidences resulting from international trials selected by Medline, and compare efficacy and side effects of different antipsychotics in people with both intellectual disability and psychotic disorders and/or behavioural disorders.

RESULTS

195 studies were identified; 117 concern traditional antipychotics while 78 new generation ones. If we consider the type of studies, it results that only the 12.8% of all production is represented by meta-analyses, systematic reviews, and randomised and not controlled trials.

CONCLUSIONS

Randomised controlled trials and systematic reviews would be the golden standard for therapeutical studies; unfortunately they are really few in this field. It is anyway significative that all the studies reported focus on the use of antipsychotics in people with intellectual disability presenting behavioural problems. To increase the validity of these studies it is recommendable to proceed only with well-designed studies, possibly double-blind versus placebo or other medications. There is need to define precise inclusion criteria, precise symptomatological or behavioural targets and adaptative ability assessment, using valid and reliable diagnostic instruments.

Rechallenge with clozapine following leucopenia or neutropenia during previous therapy

BACKGROUND

Further treatment with clozapine is contraindicated in any patient who has previously experienced leucopenia or neutropenia during clozapine therapy.

AIMS

To investigate the results of such a rechallenge in 53 patients.

METHOD

An analysis was made of the demographic, haematological and outcome data of patients in the UK and Ireland who were rechallenged with clozapine following leucopenia or neutropenia during previous clozapine therapy.

RESULTS

Of 53 patients who were rechallenged, 20 (38%) experienced a further blood dyscrasia. In 17 of these 20 patients (85%) the second blood dyscrasia was more severe (P<0.001), in 12 (60%) it lasted longer (P=0.0368) and in 17 (85%) it occurred more quickly on rechallenge (P<0.001). Of the original 53 patients, 55% (29 patients) are still receiving clozapine.

CONCLUSIONS

No clear risk factor for repeat blood dyscrasias was identified. Despite this, after risks and benefits have been considered, rechallenge may well be justified in some patients.

N-desmethyl clozapine as purging agent of leukemic cells in vitro

Attempts have been made to improve the results of autologous transplant in leukemia by purging strategies to deplete malignant cells. Clozapine is an atypical antipsychotic agent, which has been associated with hematopoietic toxicity. It has been shown that N-desmethyl clozapine a metabolite of clozapine is toxic to the hematological precursors. There is also evidence that this toxicity is confined to precursors and does not affect hematopoietic stem cells. The metabolite of clozapine (N-desmethyl clozapine) has been found to be more toxic than clozapine itself. This suggests that perhaps this metabolite can be used for purging of leukemic cells. Here it is being hypothesized that N-desmethyl clozapine could be used as an in vitro purging agent for leukemia patients. This might improve the therapeutic efficacy of autologous transplantation in leukemic patients.

Correction par le lithium des neutropénies induites par la clozapine (deux cas)

Despite the availability of new treatments, the antipsychotic effectiveness of clozapine has not been matched yet. Unfortunately, its regulation is limited by the side effects. The most detrimental is the hematologic toxicity (neutropenia and agranulocytosis) which requires a regular biological monitoring. Treatment with clozapine must be stopped in those cases of secondary granulocytopenia for about 3% of the patients. The current psychiatric drug lithium carbonate has an opposite effect: it can induce leukocytosis. Thus, lithium carbonate is administered in leukopenia, as well as in many hematologic and immunological diseases. However, few teams have used lithium in order to alleviate clozapine-induced granulocytopenia. We report here 2 patients who developed severe neutropenia (neutrophil count<1.5 yen 10 (9)/L) and for whom the use of lithium enabled us to continue the treatment by clozapine. The first patient had a granulocyte rate constitutionally low which rapidly decreased with clozapine. Thanks to the administration of lithium, he recovered quickly a normal blood cell count, which in fact was much higher than his normal rate. According to our research, it's the first time that lithium is reported to be so efficacious in a patient with such a low rate of granulocytes before treatment. It may be that clozapine is not used for those kinds of patients. The second patient developed granulocytopenia after one year of treatment with clozapine. The use of lithium increased so much the number of granulocytes that we continued the treatment with clozapine alone. After 4 months, there is no reappearance of granulocytopenia. We must take into account the partial and contradictory reports in the literature. However, if this result is confirmed, it could be of a high interest to extend the prescription of clozapine, the most effective current antipsychotic drug.

Continuing clozapine treatment despite neutropenia

RATIONALE

Approximately 1-2% of patients treated with the atypical antipsychotic clozapine develop severe neutropenia and agranulocytosis. The usual recommendation is to discontinue treatment with the drug when the peripheral neutrophil count drops below 1,500/mm3.

METHODS

We have reviewed several reports describing procedures that allowed the patients to continue clozapine treatment despite the occurrence of these haematological side effects.

RESULTS

The therapeutic procedures described (symptomatic treatment of neutropenia by co-administration of lithium or granulopoiesis-stimulating factors, management of the adjunctive medication) seem to be efficient strategies that allow continuation of clozapine treatment despite the occurrence of neutropenia. However, these types of therapy have only been used in a limited number of cases, and the evidence supporting their use remains anecdotal.

CONCLUSION

Although the procedures adopted in the cases described in this review are uncommon, they potentially provide an alternative to the discontinuation of clozapine treatment in patients with complex symptomatologies for whom treatment with other antipsychotic medication is insufficient.

The use of clozapine in adults with intellectual disability

BACKGROUND

There are not many studies on the use of clozapine in patients with intellectual disability (ID). The authors describe a case series of patients treated with clozapine, drawn from a medium secure unit, a low secure assessment and treatment service and a community team in the London region.

METHOD

A retrospective file-review of patients treated in these three settings during the time period March-June 2002 was performed (n = 24). Information was collected using a semistructured proforma.

RESULTS

Of the 24 patients, 67% had schizophrenia, 17% had schizoaffective disorder and 8% had bipolar disorder. Patients had been unwell for a mean of 6 years and had been tried on a mean of four antipsychotics. The mean maximum dose of clozapine was 488 mg. The outcomes on the clinical global impression (CGI) scale showed 29% very much improved, 42% much improved, 21% minimally improved and 8% no change. 54% of the whole sample and 53% of those from the medium secure unit were discharged to homes in the community. The drug had to be stopped in four patients, of which three were because of neutropaenia.

CONCLUSION

Clozapine appears to be safe and efficacious in many people with ID. Careful monitoring of side-effects is needed during therapy.

Clozapine-induced neutropenia in children: management with lithium carbonate

Clozapine, an atypical antipsychotic, is the most effective medication for treatment-resistant schizophrenia, but its use is limited by the high risk of neutropenia and agranulocytosis. In children, the rate of clozapine-induced neutropenia is even higher than in adults. We report two cases of children 7- and 12-years old diagnosed with very early onset schizophrenia, who developed neutropenia when treated with clozapine. In both cases addition of lithium carbonate elevated the white blood count (WBC) allowing clozapine rechallenge. WBC and total neutrophil count remained stable long-term with coadministration of clozapine (400-425 mg per day) and lithium with the blood level of 0.8-1.1 microg/mL. This report supports the use of adjunct lithium for clozapine-induced neutropenia as a safe and successful strategy in children.

Long-term combination treatment with clozapine and filgrastim in patients with clozapine-induced agranulocytosis

Short-term treatment with granulocyte colony-stimulating factor has been successful in reducing the duration of clozapine-induced agranulocytosis. Long-term combination treatment with filgrastim and clozapine in patients with clozapine-induced agranulocytosis has only been described in two previous cases. We describe three patients with schizophrenia who developed granulocytopenia or agranulocytosis during treatment with clozapine and who did not respond to other antipsychotics. The patients received long-term combination treatment with clozapine and filgrastim. Using a combination treatment with filgrastim and clozapine, the psychotic symptoms were successfully controlled and no haematological complications were observed during the follow-up periods of 11, 30 and 48 months, respectively. Our cases suggest that long-term treatment with filgrastim might be a useful, but exceptional, treatment approach in patients who have developed clozapine-induced granulocytopenia or agranulocytosis.

Clinical experience with the management of schizophrenia in the general hospital

On the basis of experience with 74 psychiatric consultations involving patients with schizophrenia admitted to a general hospital medical or surgical ward over a 17-month period (3% of the psychiatric consultations during that period), the authors identified 10 types of problems leading to requests for consultation. The authors used these categories to organize recommendations for management of patients with schizophrenia in the general medical hospital. In addition to conducting conventional consultations, the consultation psychiatrist in such cases often has a role in educating hospital staff about schizophrenia and in serving as a physician for the mentally ill.

Agranulocytosis during clozapine therapy

Granulocytopenia and agranulocytosis are considered among the most dangerous adverse effects of clozapine. During the last 15-year period, this atypical antipsychotic agent has been administered to 750 patients managed at the Emergency Psychiatry Services and Clinical Pharmacology Unit of the National Institute of Psychiatry and Neurology (NIPandN; Budapest, Hungary). Granulocytopenia was ascertained in seven, whereas agranulocytosis was diagnosed in two patients of this population. The latter two comprised a 42-year-old female with schizoaffective psychosis and a 35-year-old male with paranoid schizophrenia. The female patient received clozapine in a daily dose of 400 mg, which induced agranulocytosis after 2 months. The male patient was treated with 225-mg/day clozapine and the time to the diagnosis of agranulocytosis was 6 weeks. These adverse reactions were recognized early and the appropriate treatment of agranulocytosis resulted in complete recovery in both cases.

Olanzapine-induced agranulocytosis: a case report and review of the literature

The novel antipsychotic olanzapine has structural and pharmacological properties similar to clozapine. Until recently, no haematological toxicity has been reported with olanzapine use and it was expected to be a safer alternative. The authors report a case of agranulocytosis induced by olanzapine and reviewed the 11 cases reported in the literature.

Psychopharmacology and mental retardation: a 10 year review (1990-1999)

We conducted a 10 year review of the literature pertaining to psychopharmacology and mental retardation. Studies were included or excluded from the review based on meeting one or more of the methodological criteria normally considered fundamental for sound scientific research. The vast majority of studies conducted in the last 10 years in this area had major methodological flaws. While a large number of medications were prescribed for various psychological disorders and behavior problems, most drug administrations were not based in science, were not evaluated appropriately, and generally did not follow best practices for treatment of persons with mental retardation. Very few medications prescribed were behavior or psychiatric symptom specific; that is, most medications were given to suppress a myriad of aberrant behaviors thus chemically restraining the individual in question. Practices such as these present serious problems for service providers due to the deleterious side effects of many psychotropic medications and the federal government's intervention into the care-provision practices of developmental centers, community homes, and other living arrangements for persons with mental retardation. Implications of our review are discussed.

A second trial of clozapine in a case of granulocytopenia

It is generally believed that agranulocytosis, a major problem with clozapine treatment, will tend to occur dose-dependently once it develops in an individual. Therefore, despite clinical progress obtained, the drug has to be discontinued and treatment shifts to another drug. We report on the case of a 29-year-old woman with DSM-IV undifferentiated schizophrenia who developed agranulocytosis after 5 years of 300 mg/day clozapine treatment. The drug was withdrawn and two trials with thioridazine and olanzapine were unsuccessful. Four months after clozapine suspension, we decided to make a further trial, reintroducing clozapine titrated up to 500 mg/day. The patient's symptoms improved and blood leukocytes remained within the normal range after eight months. Copyright 2000 John Wiley & Sons, Ltd.