Facilitating prompt diagnosis and treatment of the neuroleptic malignant syndrome

Differentiating probable nitrofurantoin-induced drug fever from antipsychotic-induced hyperthermia in a patient receiving clozapine

Nitrofurantoin (NIT) is a commonly utilized antibiotic for the treatment of UTIs. Although well tolerated, NIT is not without potential adverse reactions. This case report details the observation of probable NIT-induced drug fever in a patient receiving clozapine. A 61-year-old female with treatment-refractory schizoaffective disorder was admitted to a psychiatric unit with paranoia and auditory hallucinations, prompting clozapine initiation during day 1 of hospitalization. Due to worsening hallucinations and anxiety, antibiotic therapy with NIT for a presumed UTI was initiated 8 days after admission. Febrile episodes were observed beginning on hospital day (HD) 9, leading to concern for possible neuroleptic malignant syndrome (NMS), which led to clozapine discontinuation. The patient received a total of 3 doses of NIT with continued fever until discontinuation on HD 10. No further complications were encountered, and clozapine was safely resumed on HD 13. Although sparsely described in the medical literature, occurrences of drug fever attributable to NIT are previously reported. A review of the medical literature identified only 5 previously published articles specific to NIT-induced drug fever, none of which specified interruptions of psychotropic therapy for a patient with acute psychiatric decompensation. This case highlights the differential diagnosis of fever related to NIT in a patient receiving clozapine when NMS was initially suspected.

Early detection of an atypical presentation of neuroleptic malignant syndrome: A case report

Neuroleptic malignant syndrome (NMS), which is considered a neurologic emergency, is believed to be caused by exposure to dopamine antagonist or withdrawal from a dopamine agonist. This article reports a case of suspected atypical NMS in a patient following rapid conversion of ziprasidone to risperidone without titration. While the initial presentation did not fully meet the Diagnostic and Statistical Manual of Mental Disorders, 5th edition, diagnostic features, a sequential treatment strategy was initiated and the patient appropriately responded to antipsychotic cessation in addition to combination therapy with dantrolene and bromocriptine. Neuroleptic malignant syndrome diagnostic criteria, treatment, and prognosis are discussed.

A Neuroleptic Malignant Syndrome Without Rigidity

Neuroleptic malignant syndrome (NMS) is an uncommon but potentially lethal idiosyncratic reaction which may emerge in the aftermath of the treatments with neuroleptics demonstrating itself with the symptoms of altered consciousness, high fever, impaired autonomic functions, and muscle rigidity. Although various risk factors have been identified for NMS, its etiology is not completely known. The mortality and morbidity related with NMS could be reduced by early diagnosis, interruption of the neuroleptics used within a short period and aggressive treatment. Our case is different from general NMS cases due to lack of rigidity. A NMS case which developed within a short time in the aftermath of multiple antipsychotic use and wherein no rigidity was observed shall be discussed in this case report.

Neuroleptic malignant syndrome and serotonin syndrome

The clinical manifestation of drug-induced abnormalities in thermoregulation occurs across a variety of drug mechanisms. The aim of this chapter is to review two of the most common drug-induced hyperthermic states, serotonin syndrome and neuroleptic malignant syndrome. Clinical features, pathophysiology, and treatment strategies will be discussed, in addition to differentiating between these two syndromes and differentiating them from other hyperthermic or febrile syndromes. Our goal is to both review the current literature and to provide a practical guide to identification and treatment of these potentially life-threatening illnesses. The diagnostic and treatment recommendations made by us, and by other authors, are likely to change with a better understanding of the pathophysiology of these syndromes.

Neuroleptic Malignant Syndrome with Delayed Onset of Fever Following Risperidone Administration

Objective:

To report and discuss a case of neuroleptic malignant syndrome (NMS) with delayed onset of fever in a patient taking risperidone.

Case Summary:

A 59-year-old white female presented with progressive weakness, confusion, and disorientation 10 days after restarting risperidone 2 mg/day therapy for bipolar disorder. She had taken risperidone for several years prior to this episode and had stopped it for approximately 3 weeks; risperidone was discontinued on admission. The patient's creatine kinase (CK) level was elevated (901 IU/L; reference range 39–162) on admission and increased to 1991 IU/L the following day. She was initially afebrile and had no muscular rigidity. Elevated temperature (38.1°C) did not occur until hospital day 2. The patient was successfully treated with diazepam, bromocriptine, and dantrolene and suffered no long-term sequelae.

Discussion:

Other clinicians have reported atypical presentations of NMS in patients taking newer neuroleptic agents. Although this patient met diagnostic criteria for NMS, the hallmark symptoms of fever and muscle rigidity were delayed in onset. Also, the patient never remained febrile for more than 24 hours and her maximum temperature was only 38.6°C. An objective causality assessment suggests that this case of NMS was probably related to restarting risperidone.

Conclusions:

Because of the life-threatening nature of this syndrome, clinicians should consider NMS in afebrile patients presenting with diaphoresis, changes in level of consciousness, mutism, tremors, tachycardia, leukocytosis, and elevated CK levels.

Diagnostic uncertainty in a case of neuroleptic malignant syndrome

Neuroleptic malignant syndrome (NMS) is a potentially life-threatening condition that has been associated with antipsychotic use. Most diagnostic criteria include fever and muscle rigidity, although NMS may present without either. Diagnostic uncertainty in such cases may result in delays in diagnosis and management, leading to adverse consequences for these patients. The differential diagnosis of NMS is broad and includes a number of neurological, medical and psychiatric conditions as well as substance and medication-induced disorders. A case is described that illustrates an atypical presentation of NMS and demonstrates some of the challenges in its diagnosis. Limitations of current NMS criteria are also examined, and suggestions for future criteria are presented.

Neurotoxic syndrome induced by clomipramine plus risperidone in a patient with autistic spectrum disorder: serotonin or neuroleptic malignant syndrome?

To the best of our knowledge, there are no case studies of serotonin syndrome (SS) in patients with autism spectrum disorder. We report the case of a 33-year-old male who presented SS under the combined use of clomipramine and risperidone. More specifically, within 2 days after clomipramine (10 mg/BID-two times a day) was added to risperidone (4 mg/OD-once a day), mirtazapine 45 mg/OD and alprazolam (0,5 mg/TID-three times a day) he began to present mental, neurological and autonomic symptoms. All his psychopathological manifestations and laboratory findings normalized after the above-mentioned drugs' discontinuation, and the administration of supportive medical care and lorazepam 2,5 mg/TID. The diagnosis of serotonin syndrome was challenging due to the relatively low dose of clomipramine, an increase of risperidone which had taken place before clomipramine administration and clinical symptoms which could be attributed to both serotonin and neuroleptic malignant syndrome.

Case reports of neuroleptic malignant syndrome in context of quetiapine use

A retrospective analysis was followed on 20 case reports covering the possible correlation between the atypical antipsychotic, quetiapine, and neuroleptic malignant syndrome (NMS), determined by the study of 7 different NMS criteria guidelines. A great majority (19) of the case studies did not meet the requirements of all 7 guidelines, frequently due to unreported information. Nor was quetiapine proven to be the sole cause of the possible NMS in the two age groups investigated. Only one case was found to have no other medication or medical conditions confounding the relationship of quetiapine and NMS symptoms, and that case was in the context of a significant quetiapine overdose. The other 19 cases demonstrated the difficulty of identifying the cause of NMS when polypharmacy and other medical conditions are involved. The authors note the need for caution in deciding both the presence of NMS and the causal factors of the symptoms.

From Bench to Bedside: Understanding the Science behind the Pharmacologic Management of MDMA- and other Sympathomimetic-Mediated Hyperthermia

Objective:

To evaluate the scientific rationale and efficacy of pharmacologic and nonpharmacologic treatments for sympathomimetic-induced hyperthermia and related sequelae.

Data Sources:

Literature was accessed through MEDLINE (1940-September 2010) using the terms MDMA [3,4-methylenedioxymethamphetamine], methamphetamine, toxicity, and hyperthermia. In addition, reference citations from identified publications were reviewed.

Study Selection and Data Extraction:

All articles written in English identified from data sources were evaluated.

Data Synthesis:

The treatment of sympathomimetic-induced hyperthermia is a challenging problem for health-care professionals. The lack of clinical trials further complicates the development of evidence-based treatment algorithms. Preclinical studies have mostly been with the sympathomimetic MDMA and have demonstrated a reversal of MDMA-induced hyperthermia with a mixed serotonin 5-HT1A agonist/5-HT2A antagonist or mixed α1- and β1,2,3-adrenergic receptor antagonists.

Conclusions:

Because of the nature by which patients are exposed to these agents, therapeutic interventions for sympathomimetic-mediated hyperthermia still lack evidence from clinical trials with human subjects. Pharmacologic treatments that should be avoided are antipyretics and the ryanodine receptor antagonist dantrolene. Promising future therapies may involve mixed 5-HT1A agonist/5-HT2A antagonists such as the atypical antipsychotic olanzapine, or mixed α1- and β1,2,3-adrenergic receptor antagonists such as carvedilol, as current preclinical research suggests.

Association Between Selective Serotonin-Reuptake Inhibitors, Second-Generation Antipsychotics, and Neuroleptic Malignant Syndrome

Objective

To review the published reports of neuroleptic malignant syndrome (NMS) associated with the use of selective serotonin-reuptake inhibitors (SSRIs) and second-generation antipsychotics.

Data Source:

Information was selected from a MEDLINE search of English-language literature (1950–May 2008). Manual search of all published cases indexed in MEDLINE (English language only) of NMS associated with second-generation antipsychotics was also performed.

Study Selection And Data Extraction:

Pertinent information from all reports obtained was included, with specific emphasis on patient age, sex, second-generation antipsychotic involved, SSRI or other antidepressant involved, time of onset of NMS symptoms in relation to medication changes, treatment administered, and outcome of the reaction.

Data Synthesis:

NMS has been reported with every second-generation antipsychotic agent. It is unclear whether concomitant therapy with other agents may increase the risk of NMS development via pharmacodynamic or pharmacokinetic mechanisms or both, The suggested pharmacodynamic mechanism for increased risk of NMS with concomitant use of SSRIs is the effect of serotonin on dopamine release. Serotonin further inhibits dopamine release and thereby may worsen a hypodopaminergic state induced by antipsychotics. Pharmacokinetic factors may also play a role in some NMS cases involving an SSRI by increasing antipsychotic concentrations. An examination of case reports seems to indícale that at least in some casos, a temporal relationship exists with the addition of an SSRI to existing antipsychotic therapy.

Conclusions:

The use of SSRIs may be associated with an increased risk of NMS development in (hose receiving second-generation antipsychotics. Clinicians should closely monitor patients for the potential development of NMS.

Bench-to-bedside review: mechanisms and management of hyperthermia due to toxicity

Body temperature can be severely disturbed by drugs capable of altering the balance between heat production and dissipation. If not treated aggressively, these events may become rapidly fatal. Several toxins can induce such non-infection-based temperature disturbances through different underlying mechanisms. The drugs involved in the eruption of these syndromes include sympathomimetics and monoamine oxidase inhibitors, antidopaminergic agents, anticholinergic compounds, serotonergic agents, medicaments with the capability of uncoupling oxidative phosphorylation, inhalation anesthetics, and unspecific agents causing drug fever. Besides centrally disturbed regulation disorders, hyperthermia often results as a consequence of intense skeletal muscle hypermetabolic reaction. This leads mostly to rapidly evolving muscle rigidity, extensive rhabdomyolysis, electrolyte disorders, and renal failure and may be fatal. The goal of treatment is to reduce body core temperature with both symptomatic supportive care, including active cooling, and specific treatment options.

Zuclopenthixol-induced neuroleptic malignant syndrome in an adolescent girl

We present the case of a 14-year-old female who had many characteristics of neuroleptic malignant syndrome (NMS) without pyrexia following a single depot injection of 200 mg of zuclopenthixol. The patient presented with a change in mental status that had progressed over the preceding 48 hours. Subsequently, she became increasingly agitated and confused, and developed diffuse muscular rigidity, mutism, tremor, tachycardia, diaphoresis, sialorrhea, and incontinence. Results of laboratory tests showed elevated CPK levels, leukocytosis, and a low serum iron level. Bromocriptine and diazepam were used as initial treatment of a probable NMS and provided significant improvement. During the next seven days, she clinically improved but continued to exhibit emotional lability, logorrhea, elevated mood, and increased psychomotor activity. Therefore, bromocriptine and diazepam were discontinued and lorazepam and lithium were administered as treatment of a bipolar disorder. Four weeks later, she was discharged in stable condition. The presentation of this case report suggests that the primary psychiatric diagnosis is important in antipsychotic usage in the pediatric population, and that young patients receiving neuroleptic treatment should be monitored for the early signs of NMS. Using the diagnostic criteria of a neuroleptic toxicity spectrum may result in greater clinical awareness and earlier recognition of NMS.

Hyperthermic Syndromes Induced by Toxins

Normal thermogenesis requires a complex interaction between systems that generate and dissipate heat. Serving as director of thermogenesis, the hypothalamus activates the sympathetic nervous system along with the thyroid and adrenal glands to respond to changes in body temperature. Working in concert, these systems result in heat generation by uncoupling of oxidative phosphorylation, combined with impaired heat dissipation through vasoconstriction. In this article, the authors discuss serotonin and sympathomimetic syndromes, neuroleptic malignant syndrome,and malignant hyperthermia and how these syndromes affect the hypothalamic and sympathetic nervous systems, resulting at times in severe hyperthermia. Current treatment recommendations and future trends in treatment are also discussed.

Toxin-induced hyperthermic syndromes

Toxin-induced hyperthermic syndromes are important to consider in the differential diagnosis of patients presenting with fever and muscle rigidity. If untreated, toxin-induced hyperthermia may result in fatal hyperthermia with multisystem organ failure. All of these syndromes have at their center the disruption of normal thermogenic mechanisms, resulting in the activation of the hypothalamus and sympathetic nervous systems.The result of this thermogenic dysregulation is excess heat generation combined with impaired heat dissipation. Although many similarities exist among the clinical presentations and pathophysiologies of toxin-induced hyperthermic syndromes, important differences exist among their triggers and treatments. Serotonin syndrome typically occurs within hours of the addition ofa new serotonergic agent or the abuse of stimulants such as MDMA or methamphetamine. Treatment involves discontinuing the offending agent and administering either a central serotonergic antagonist, such as cyproheptadine or chlorpromazine, a benzodiazepine, or a combination of the two. NMS typically occurs over hours to days in a patient taking a neuroleptic agent; its recommended treatment is generally the combination of a central dopamine agonist, bromocriptine or L-dopa, and dantrolene. In those patients in whom it is difficult to differentiate between serotonin and neuroleptic malignant syndromes, the physical examination may be helpful:clonus and hyperreflexia are more suggestive of serotonin syndrome,whereas lead-pipe rigidity is suggestive of NMS. In patients in whom serotonin syndrome and NMS cannot be differentiated, benzodiazepines represent the safest therapeutic option. MH presents rapidly with jaw rigidity, hyperthermia, and hypercarbia. Although it almost always occurs in the setting of surgical anesthesia, cases have occurred in susceptible individuals during exertion. The treatment of MH involves the use of dantrolene. Future improvements in understanding the pathophysiology and clinical presentations of these syndromes will undoubtedly result in earlier recognition and better treatment strategies.

The role of the sympathetic nervous system and uncoupling proteins in the thermogenesis induced by 3,4-methylenedioxymethamphetamine

Body temperature regulation involves a homeostatic balance between heat production and dissipation. Sympathetic agents such as 3,4-methylenedioxymethamphetamine (MDMA, ecstasy) can disrupt this balance and as a result produce an often life-threatening hyperthermia. The hyperthermia induced by MDMA appears to result from the activation of the sympathetic nervous system (SNS) and the hypothalamic-pituitary-thyroid/adrenal axis. Norepinephrine release mediated by MDMA creates a double-edged sword of heat generation through activation of uncoupling protein (UCP3) along with alpha1- and beta3-adrenoreceptors and loss of heat dissipation through SNS-mediated vasoconstriction. This review examines cellular mechanisms involved in MDMA-induced thermogenesis from UCP activation to vasoconstriction and how these mechanisms are related to other thermogenic conditions and potential treatment modalities.

Fulminant neuroleptic malignant syndrome after perioperative withdrawal of antiParkinsonian medication

Neuroleptic malignant syndrome is a rare complication when using neuroleptic drugs. We report the case of a patient with severe Parkinson's disease who developed neuroleptic malignant syndrome after withdrawal of his antiParkinsonian medication for elective coronary artery bypass grafting. Sodium dantrolene may be a therapeutic option in severe cases.

Drug-induced hyperthermia and muscle rigidity: a practical approach

Body thermoregulation can be violently offset by drugs capable of altering the balance between heat production and dissipation. Such events may rapidly become fatal. The drugs that are involved in the eruption of such syndromes include inhalation anaesthetics, sympathomimetic agents, serotonin antagonists, antipsychotic agents and compounds that exhibit anticholinergic properties. The resultant hyperthermia is frequently accompanied by an intense skeletal muscle hypermetabolic reaction that leads to rapidly evolving rigidity, extensive rhabdomyolysis and hyperkalemia. The differential diagnosis should, however, rule out non-drug-induced causes, such as lethal catatonia, central nervous system infection or tetanus, strychnine poisoning, thyrotoxic storm and pheochromocytoma. Prompt life-saving procedures include aggressive body temperature reduction. Patients with a suspected drug (or non-drug) hypermetabolic reaction should be admitted into an intensive care area for close monitoring and system-oriented supportive treatment. We present six conditions, in decreasing order of gravity and potential lethality, in which hyperthermia plays an essential role, and suggest a clinical approach in such conditions.

Atypical neuroleptic malignant syndrome associated with olanzapine

Neuroleptic malignant syndrome (NMS) is a potentially life-threatening adverse effect of antipsychotic agents. It generally is characterized by fever, altered mental status, rigidity, and autonomic dysfunction. A 53-year-old man developed NMS without rigidity while taking olanzapine. Such atypical cases may support either a spectrum concept of NMS or the theory that NMS secondary to atypical antipsychotics differs from that caused by conventional neuroleptics. More flexible diagnostic criteria than currently mandated by the the Diagnostic and Statistical Manual of Mental Disorders, Fourth Revision, may be warranted.

The use of clonidine in the management of autonomic overactivity in neuroleptic malignant syndrome

The aim of this study was to identify the effectiveness of clonidine in the recovery of patients with neuroleptic malignant syndrome and autonomic dysfunction, including blood pressure lability. Nine patients with neuroleptic malignant syndrome and autonomic dysfunction were treated with clonidine in the intensive care unit, according to a protocol, and the results were compared with those of seven patients with the same syndrome who were not treated with clonidine. Clonidine was administered until blood pressure stability was fully restored, and thereafter the dose was gradually reduced. There was a significant reduction in the duration of ventilation and stay in the intensive care unit in the clonidine group. Three patients from the nonclonidine group died. The data suggest that in the clonidine group, patients with neuroleptic malignant syndrome and autonomic dysfunction appear to have better and faster recovery, especially in blood pressure control, after intravenous clonidine treatment.

Acute basagran poisoning mimicking neuroleptic malignant syndrome

A 27-year-old robust man, without any medical and surgical history, attempted to commit suicide by consumption of 300 cc (44.1%, 132.3 g) basagran, a readily available herbicide. This poisoning resulted in vomiting, fever, sweating, pipe-like muscle rigidity, sinus tachycardia, drowsiness, leukocytosis, rhabdomyolysis and hepatorenal damage. Emperical treatment with bromocriptine was temporally associated with resolution of above signs and symptoms. His clinical presentations and the effect of bromocriptine may be indicative that basagran poisoning mimicks neuroleptic malignant syndrome.

A veteran with acute mental changes years after combat

A 49-year-old man presented with a five-week history of worsening confusion, agitation, and bizarre behavior. According to his mother and sister, who live with him, he had inexplicably jumped out of bed one day and complained of injuring his back. The pain apparently resolved within several days. Two weeks later, again just after awakening, he had experienced a period of confusion, lasting about 15 min. The latest episode occurred three days previously and included vivid hallucinations--at various times, he seemed to believe that he was talking to his brother on the telephone, drinking a glass of water, emptying the refrigerator, jumping into a foxhole, and stomping on rattlesnakes. He was disoriented to time as well as environment.

Atypical Neuroleptic Malignant Syndrome Presenting as Rhabdomyolysis, Altered Consciousness, and Leukocytosis

Objective:

To provide a clinically accurate description of an atypical form of neuroleptic malignant syndrome (NMS) induced by perphenazine, to underline the importance of early diagnosis of this atypical form of NMS, and to stimulate discussion of possible mechanisms of this adverse drug event.

Case Summary:

A 61-year-old man had received perphenazine for 5 years for treatment of schizophrenia. He presented with progressive muscle rigidity, difficulty walking, and lower back pain. He was found to be disoriented and confused with tardive dyskinesia and muscle weakness. The patient was afebrile and normotensive. Clinical workup and laboratory test results were consistent with a diagnosis of rhabdomyolysis. The patient was treated with rehydration and sodium bicarbonate. Perphenazine therapy was discontinued and the symptoms resolved within 3 days.

Discussion:

Rhabdomyolysis has been reported in patients receiving psychotropic drugs, but the frequency of the occurrence is not known. The most frequent cause of rhabdomyolysis in psychiatric patients is NMS; however, this patient had only part of the classical picture of NMS. Other cases of atypical presentation are reviewed.

Conclusions:

Muscle injury in the presence of psychotropic drugs can manifest in many different ways. This suggests a complex mechanism of injury, involving central mechanisms as well as direct injury to the muscle.

Fluoxetine and the serotonin syndrome

A 48-year-old man presented to the emergency department with confusion, agitation, diaphoresis, and muscle rigidity after beginning treatment with fluoxetine, a serotonin reuptake inhibitor. He had discontinued treatment with tranylcypromine, a monoamine oxidase inhibitor, 2 weeks earlier. The constellation of findings was diagnostic of the serotonin syndrome.

Neuroleptic Malignant Syndrome: A Review for Intensivists

Neuroleptic malignant syndrome (NAIS) is arare, potentially life-threatening disorder that results from the use of neuroleptics, a class of drugs that is being used with increasing frequency in intensive care units (ICUs). Unfortunately, critically ill patients typically have coexisting conditions that make accurate diagnosis of NAIS difficult and complicate treatment decisions. Diagnostic criteria, risk factors, and treatment options for NMS are discussed; case examples are provided.