Memantine and catatonia: a case report and literature review

The Clinical Course of a Severe Case of Malignant Catatonia

Catatonia is a psychomotor syndrome predominantly associated with mental illness disorders, most commonly bipolar disorder and schizophrenia. Catatonia is classified as malignant when, in addition to catatonic symptoms, dysautonomia is present. Autonomic abnormalities can include changes in temperature, labile blood pressure, and changes in heart and respiratory rates. Because malignant catatonia is life-threatening, prompt recognition and management are essential to prevent mortality. We present a severe case of catatonia with malignant features that highlight the importance of early diagnosis and treatment.

Life-threatening altered mental status secondary to memantine in an adolescent undergoing cranial radiotherapy for medulloblastoma

INTRODUCTION

Memantine is used for neurocognitive protection in patients undergoing cranial radiotherapy for central nervous system tumors and is reported to be well-tolerated.

CASE REPORT

Presented is a case of memantine-induced altered mental status requiring an intensive care unit admission. An 18-year-old male with relapsed, progressive medulloblastoma presented with severe altered mental status shortly after the first fraction of palliative whole brain radiotherapy. At the time, the patient was on day five of memantine therapy, which had been prescribed to reduce neurocognitive toxicity risk.

MANAGEMENT & OUTCOME

Memantine was withheld while dexamethasone, valproate, and morphine were continued for headache. Approximately 50 h after admission, the patient's confusion significantly improved. Evaluation of acute altered mental status was unrevealing, including but not limited to negative urinary toxicology screen and lack of disease progression on imaging. Whole brain radiotherapy was resumed after a two-day cessation and he was discharged home after four days with complete resolution of symptoms.

DISCUSSION

Clinicians should be aware of and consider the risk of altered mental status with memantine, given the increased utilization and upcoming clinical trials in pediatric patients.

Molecular and cellular mechanisms leading to catatonia: an integrative approach from clinical and preclinical evidence

This review aims to describe the clinical spectrum of catatonia, in order to carefully assess the involvement of astrocytes, neurons, oligodendrocytes, and microglia, and articulate the available preclinical and clinical evidence to achieve a translational understanding of the cellular and molecular mechanisms behind this disorder. Catatonia is highly common in psychiatric and acutely ill patients, with prevalence ranging from 7.6% to 38%. It is usually present in different psychiatric conditions such as mood and psychotic disorders; it is also a consequence of folate deficiency, autoimmunity, paraneoplastic disorders, and even autistic spectrum disorders. Few therapeutic options are available due to its complexity and poorly understood physiopathology. We briefly revisit the traditional treatments used in catatonia, such as antipsychotics, electroconvulsive therapy, and benzodiazepines, before assessing novel therapeutics which aim to modulate molecular pathways through different mechanisms, including NMDA antagonism and its allosteric modulation, and anti-inflammatory drugs to modulate microglia reaction and mitigate oxidative stress, such as lithium, vitamin B12, and NMDAr positive allosteric modulators.

Is Memantine Effective as an NMDA-Receptor Antagonist in Adjunctive Therapy for Schizophrenia?

Memantine, an n-methyl-d-aspartate (NMDA) receptor antagonist approved for treating Alzheimer's disease, has a good safety profile and is increasingly being studied for possible use in a variety of non-dementia psychiatric disorders. There is an abundance of basic and clinical data that support the hypothesis that NMDA receptor hypofunction contributes to the pathophysiology of schizophrenia. However, there are numerous randomized, double-blind, placebo-controlled clinical trials showing that add-on treatment with memantine improves negative and cognitive symptoms, particularly the negative symptoms of schizophrenia, indicating that memantine as adjunctive therapy in schizophrenia helps to ameliorate negative symptoms and cognitive deficits. It remains unclear why memantine does not show undesirable central nervous system (CNS) side effects in humans unlike other NMDA receptor antagonists, such as phencyclidine and ketamine. However, the answer could lie in the fact that it would appear that memantine works as a low-affinity, fast off-rate, voltage-dependent, and uncompetitive antagonist with preferential inhibition of extrasynaptic receptors. It is reasonable to assume that the effects of memantine as adjunctive therapy on negative symptoms and cognitive deficits in schizophrenia may derive primarily, if not totally, from its NMDA receptor antagonist activity at NMDA receptors including extrasynaptic receptors in the CNS.

Alternative treatment strategies for catatonia: A systematic review

BACKGROUND

Catatonia is a commonly encountered syndrome, affecting 10-20% of various psychiatric populations and carrying significant medical co-morbidities. However, there are few established alternative treatment strategies when benzodiazepines are ineffective and electroconvulsive therapy is unavailable.

OBJECTIVE

The authors systematically review evidence for alternative treatment strategies for catatonia using Preferred Reporting Items for Systematic reviews and Meta-Analyses (PRISMA) guidelines.

METHOD

The authors conducted a search of PubMed database from 1983 to August 2016 to identify articles. Eligible reports presented cases involving treatment of catatonia using modalities other than benzodiazepines or electroconvulsive therapy.

RESULTS

The authors identified 72 articles, comprising 98 individual cases. N-methyl-d-aspartate-receptor antagonists, anti-epileptic drugs, and atypical antipsychotic agents appeared to have the largest number of reports supporting their effectiveness and safety in treating catatonia patients.

CONCLUSIONS

Based on the case report literature, the authors propose an updated algorithm for catatonia treatment in cases where benzodiazepines fail and electroconvulsive therapy is not available.

Commentary on 2 Cases Involving Psychiatric Problems Following Organ Transplantation

Organ transplantation may be complicated by a range of psychiatric difficulties. We present 1 case reporting that tacrolimus-induced catatonic delirium after liver transplant responded to memantine, and another case illustrating the need for ongoing psychosocial assessment and support after heart transplant.

Prolonged Delirium With Catatonia Following Orthotopic Liver Transplant Responsive to Memantine

A 59-year-old man with nonalcoholic steatohepatitis cirrhosis underwent an orthotopic liver transplant and experienced a complicated postoperative course, including a prolonged delirium. After discharge to rehabilitation, he had 2 subsequent admissions for delirium. On the first readmission, the transplant team started the patient on risperidone and resumed treatment with sertraline. On his second readmission, neurology and psychiatry were consulted. On evaluation, the patient demonstrated signs of catatonia. On the basis of recommendations from psychiatry, the risperidone and sertraline were stopped, and the patient was started on mirtazapine. He failed to demonstrate improvement within the next 48 hours. Extensive work-up demonstrated a multifactorial etiology for his delirium, including calcineurin-related neuropsychiatric toxicity from tacrolimus leading to possible posterior reversible encephalopathy syndrome. However, after the initiation of memantine on hospital day 3-before the cessation of tacrolimus-the patient demonstrated marked improvement in mental status and motor symptoms. His magnetic resonance imaging, in addition to findings that raised concerns about posterior reversible encephalopathy syndrome, had demonstrated bilateral basal ganglia abnormalities on T1 imaging of uncertain origin. It is postulated that these findings served as predisposing factors for the patient's catatonic symptoms. Although it has been described in case reports following liver transplant, catatonia remains an underrecognized neuropsychiatric complication following liver transplant. This case demonstrates the effectiveness of memantine, an N-methyl-D-aspartic acid antagonist that decreases glutamine excitotoxicity, as a potential treatment for catatonia in postliver transplant patients.

Unrecognized catatonia as a cause for delayed weaning in Intensive Care Unit

The cause of altered sensorium in critical care settings includes metabolic derangements, drug and toxin overdose, central nervous system infections, neurodegenerative disorders, vascular events, hypo-perfusion states, and septic encephalopathy. Here, we present a case of an elderly woman who presented to us with altered sensorium with respiratory failure requiring mechanical ventilation. Her metabolic parameters, imaging, and cerebrospinal fluid study were all normal despite that she continued to remain in altered sensorium and had an unrecognized behavioral state that delayed her weaning.

Movement disorders in catatonia

Catatonia is a complex neuropsychiatric syndrome characterised by a broad range of motor, speech and behavioural abnormalities. 'Waxy flexibility', 'posturing' and 'catalepsy' are among the well-recognised motor abnormalities seen in catatonia. However, there are many other motor abnormalities associated with catatonia. Recognition of the full spectrum of the phenomenology is critical for an accurate diagnosis. Although controlled trials are lacking benzodiazepines are considered first-line therapy and N-Methyl-d-aspartate receptor antagonists also appears to be effective. Electroconvulsive therapy is used in those patients who are resistant to medical therapy. An underlying cause of the catatonia should be identified and treated to ensure early and complete resolution of symptoms.

Anti-NMDA receptor antibodies in patients with a first episode of schizophrenia

BACKGROUND

Encephalitis with antibodies against N-methyl-D-aspartate receptor (NMDA-R) is classified as an autoimmune disorder with psychotic symptoms, which are frequently dominant. However, it remains unclear how frequently NMDA-R antibodies lead to a condition that mimics psychosis and first-episode schizophrenia. In our work, we investigated the presence of antibodies against NMDA-R in patients with first-episode psychosis (FEP) in comparison with healthy volunteers.

METHODS

This study included 50 antipsychotic-naïve patients with FEP (including 21 women) and 50 healthy volunteers (including 21 women). The mean age of the patients was 27.4 (±7.4) years and that of the healthy controls was 27.0 (±7.3) years. Antibodies against NMDA-R in the serum were detected by immunofluorescence.

RESULTS

None of the investigated patients with an FEP and none of the healthy controls showed positive antibodies against NMDA-Rs.

CONCLUSION

According to results of studies, a small proportion of patients with an FEP possess antibodies against NMDA-R. However, the extent to which this finding contributes to the etiopathogenesis of the response to antipsychotic medication and whether immunomodulatory therapy is indicated in these cases remains uncertain.

Memantine: New prospective in bipolar disorder treatment

We review preclinical and clinical evidences strongly suggesting that memantine, an old drug currently approved for Alzheimer's dementia, is an effective treatment for acute mania and for the prevention of manic/hypomanic and depressive recurrences of manic-depressive illness. Lithium remains the first line for the treatment and prophylaxis of bipolar disorders, but currently available treatment alternatives for lithium resistant patients are of limited and/or questionable efficacy. Thus, research and development of more effective mood stabilizer drugs is a leading challenge for modern psychopharmacology. We have demonstrated that 21 d administration of imipramine causes a behavioural syndrome similar to a cycle of bipolar disorder, i.e., a mania followed by a depression, in rats. Indeed, such treatment causes a behavioural supersensitivity to dopamine D2 receptor agonists associated with an increase sexual activity and aggressivity (mania). The dopamine receptor sensitization is followed, after imipramine discontinuation, by an opposite phenomenon (dopamine receptor desensitization) and an increased immobility time (depression) in the forced swimming test of depression. Memantine blocks the development of the supersensitivity and the ensuing desensitization associated with the depressive like behavior. On the basis of these observations we have suggested the use of memantine in the treatment of mania and in the prophylaxis of bipolar disorders. To test this hypothesis we performed several naturalistic studies that showed an acute antimanic effect and a long-lasting and progressive mood-stabilizing action (at least 3 years), without clinically relevant side effects. To confirm the observations of our naturalistic trials we are now performing a randomized controlled clinical trial. Finally we described the studies reporting the efficacy of memantine in manic-like symptoms occurring in psychiatric disorders other than bipolar.

LIMITATIONS

A randomized controlled clinical trial is needed to confirm our naturalistic observations.

CONCLUSION

We believe that this review presents enough pharmacological and clinical information to consider the administration of memantine in the treatment of bipolar disorders that no respond to standard mood stabilizers.

Prevalence of anti-N-methyl-D-aspartate (NMDA) receptor [corrected] antibodies in patients with schizophrenia and related psychoses: a systematic review and meta-analysis

BACKGROUND

Anti-N-methyl-D-aspartate (NMDA) receptor encephalitis is an autoimmune condition caused by immunoglobulin (Ig)G antibodies directed against the NR1 subunit of the NMDA glutamate receptor. Approximately 65% of cases present with psychiatric symptoms, particularly psychosis. It remains to be established whether anti-NMDA receptor antibodies can cause a 'purely' psychotic illness without overt neurological symptoms.

METHOD

We conducted a systematic literature search to establish what proportion of patients with schizophrenia and related psychoses have antibodies directed against the NMDA receptor. Studies were included if (a) subjects had a diagnosis of schizophrenia, schizophrenia spectrum disorder or first-episode psychosis (FEP) using standard criteria, (b) serum was analysed for the presence of anti-NMDA receptor antibodies; and (c) the purpose of the study was to look for the presence of anti-NMDA receptor antibodies in patients with a primary psychiatric diagnosis without clinical signs of encephalitis.

RESULTS

Seven studies were included, comprising 1441 patients, of whom 115 [7.98%, 95% confidence interval (CI) 6.69-9.50] were anti-NMDA receptor antibody positive. Of these, 21 (1.46%, 95% CI 0.94-2.23) patients were positive for antibodies of the IgG subclass. Prevalence rates were greater in cases than controls only for IgG antibodies; other subclasses are of less certain aetiological relevance. There was significant heterogeneity in terms of patient characteristics and the antibody assay used.

CONCLUSIONS

A minority of patients with psychosis are anti-NMDA receptor antibody positive. It remains to be established whether this subset of patients differs from antibody-negative patients in terms of underlying pathology and response to antipsychotic treatment, and whether immunomodulatory treatments are effective in alleviating psychotic symptoms in this group.

Catatonia in the ICU: an important and underdiagnosed cause of altered mental status. a case series and review of the literature*

OBJECTIVE

Catatonia is a neuropsychiatric syndrome with motor and behavioral symptoms occurring in patients with or without a history of psychiatric illness. Although it is associated with significant morbidity and mortality, the prevalence of catatonia in the ICU setting is unknown. The diagnosis and management of catatonia in the critically ill patient raises unique challenges. Furthermore, the diagnosis and management are not included in most critical care curricula. The objective of this retrospective study is to increase the awareness of this clinically important condition among critical care providers.

DESIGN

Retrospective case series study.

SETTING

Multiple critical care units at a university-affiliated tertiary care hospital.

PATIENTS

Five critically ill patients with catatonia, aged 17 to 78.

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

All notes, laboratory data, imaging results, other diagnostic studies, therapeutic interventions, and responses to treatment were reviewed for five critically ill patients with catatonia. No unifying cause of catatonia or predisposing conditions were identified for these patients. Currently available diagnostic criteria for catatonia were found to be nonspecific in the ICU setting. New diagnostic criteria for catatonia specific to the critically ill patient are proposed.

CONCLUSIONS

Catatonia can occur in a wide variety of critical care settings, with or without precedent psychiatric illness, and it may be exacerbated or induced by common intensive care practices. Psychomotor findings are imperative in examination of critically ill patients with altered mental status in order to diagnose catatonia.

Current electroconvulsive therapy practice and research in the geriatric population

Electroconvulsive therapy (ECT) is utilized worldwide for various severe and treatment-resistant psychiatric disorders. Research studies have shown that ECT is the most effective and rapid treatment available for elderly patients with depression, bipolar disorder and psychosis. For patients who suffer from intractable catatonia and neuroleptic malignant syndrome, ECT can be life saving. For elderly patients who cannot tolerate or respond poorly to medications and who are at a high risk for drug-induced toxicity or toxic drug interactions, ECT is the safest treatment option. Organic causes are frequently associated with late-life onset of neuropsychiatric conditions, such as parkinsonism, dementia and stroke. ECT has proven to be efficacious even when these conditions are present. During the next decade, research studies should focus on the use of ECT as a synergistic therapy, to enhance other biological and psychological treatments, and prevent symptom relapse and recurrence.

A clinical review of the treatment of catatonia

Catatonia is a severe motor syndrome with an estimated prevalence among psychiatric inpatients of about 10%. At times, it is life-threatening especially in its malignant form when complicated by fever and autonomic disturbances. Catatonia can accompany many different psychiatric illnesses and somatic diseases. In order to recognize the catatonic syndrome, apart from thorough and repeated observation, a clinical examination is needed. A screening instrument, such as the Bush-Francis Catatonia Rating Scale, can guide the clinician through the neuropsychiatric examination. Although severe and life-threatening, catatonia has a good prognosis. Research on the treatment of catatonia is scarce, but there is overwhelming clinical evidence of the efficacy of benzodiazepines, such as lorazepam, and electroconvulsive therapy.

A 10-week memantine treatment in bipolar depression: a case report. Focus on depressive symptomatology, cognitive parameters and quality of life

Memantine and other glutamatergic agents have been currently investigated in some off-label indications due to glutamatergic involvement in several psychoneurological disorders. We assumed that memantine similarly to ketamine may positively influence mood, moreover having a potential to improve cognition and general quality of life. We report a case of a 49-year-old male hospitalized during a manic and a subsequent moderate depressive episode. After an ineffective use of lithium, olanzapine and antidepressive treatment with mianserin, memantine was added up to 20 mg per day for 10 weeks. The mental state was assessed using the Hamilton Depression Rating Scale, the Young Mania Rating Scale, the Hamilton Anxiety Scale, the Clinical Global Inventory, the World Health Organization Quality of Life Scale and psychological tests. After 10 weeks the patient achieved a partial symptomatic improvement in mood, anxiety and quality of sleep, but his activity remained insufficient. We also observed an improvement in the parameters of cognitive functioning and quality of life. There was neither significant mood variations during the memantine use nor mood changes after its termination. No significant side effects were noted during the memantine treatment. We conclude that using memantine in bipolar depression may improve mood, cognitive functioning and quality of life.

The role of memantine in the treatment of psychiatric disorders other than the dementias: a review of current preclinical and clinical evidence

Memantine, a non-competitive NMDA receptor antagonist approved for Alzheimer's disease with a good safety profile, is increasingly being studied in a variety of non-dementia psychiatric disorders. We aimed to critically review relevant literature on the use of the drug in such disorders. We performed a PubMed search of the effects of memantine in animal models of psychiatric disorders and its effects in human studies of specific psychiatric disorders. The bulk of the data relates to the effects of memantine in major depressive disorder and schizophrenia, although more recent studies have provided data on the use of the drug in bipolar disorder as an add-on. Despite interesting preclinical data, results in major depression are not encouraging. Animal studies investigating the possible usefulness of memantine in schizophrenia are controversial; however, interesting findings were obtained in open studies of schizophrenia, but negative placebo-controlled, double-blind studies cast doubt on their validity. The effects of memantine in anxiety disorders have been poorly investigated, but data indicate that the use of the drug in obsessive-compulsive disorder and post-traumatic stress disorder holds promise, while findings relating to generalized anxiety disorder are rather disappointing. Results in eating disorders, catatonia, impulse control disorders (pathological gambling), substance and alcohol abuse/dependence, and attention-deficit hyperactivity disorder are inconclusive. In most psychiatric non-Alzheimer's disease conditions, the clinical data fail to support the usefulness of memantine as monotherapy or add-on treatment However, recent preclinical and clinical findings suggest that add-on memantine may show antimanic and mood-stabilizing effects in treatment-resistant bipolar disorder.