Neuroleptic malignant syndrome and malignant hyperthermia. Important issues for the medical consultant

Treatment with Botulinum Toxin for Refractory Fever Caused by Severe Spasticity: A Case Series

Introduction

Brain and spinal cord injuries may cause very severe spasticity that occasionally may be associated with persistent fever.

Case Series

We present 14 patients with spasticity and persistent fever, treated with botulinum toxin type A. Their spasticity improved and the fever resolved within a period no greater than 48 h. In all cases, infectious and other non-infectious causes were ruled out.

Conclusions

When sustained tonic muscular activity is associated with a significant increase in body temperature and is refractory to the usual drugs used for hyperpyrexia, type A botulinum toxin may be an effective treatment option to control both spasticity and fever.

Atypical Neuroleptic Malignant Syndrome Associated with Use of Clozapine

The Neuroleptic Malignant Syndrome (NMS) is a medical emergency of infrequent presentation in the emergency department, which is associated with the use of psychiatric drugs, such as typical and atypical antipsychotics. Our case addresses a 55-year-old patient diagnosed with undifferentiated schizophrenia for 10 years, who had been receiving clozapine and clonazepam as part of their treatment. This patient presents the symptoms of Neuroleptic Malignant Syndrome without fever, which improves with treatment especially with the withdrawal of clozapine. In the absence of fever and clinical improvement, the patient is considered to have an atypical presentation of this disease.

Fluphenazine-Induced Neuroleptic Malignant Syndrome in a Schizophrenic Patient

OBJECTIVE:

To report a case of neuroleptic malignant syndrome (NMS) associated with fluphenazine in a schizophrenic patient and review the literature related to this condition.

CASE SUMMARY:

A 21-year-old African American male with schizophrenia came to our medical intensive care unit from the crisis intervention unit (CIU). He was hyperthermic (oral temperature 40.6 °C), diaphoretic, tachycardic (heart rate 140 beats/min), and tachypneic (respiratory rate 22 breaths/min), with severe muscle rigidity and shaking tremors. He had an extensive psychiatric history significant for schizophrenia and multiple past hospital admissions, starting at age 14 years. Two days prior to admission to the CIU, he had been given 25 mg of fluphenazine decanoate injection intramuscularly in addition to his regular psychotropic regimen of thioridazine and haloperidol after reportedly making several verbal threats and displaying aggressive behavior toward the personnel at the group home where he resided. Laboratory studies showed elevated creatine kinase, aspartate aminotransferase, alanine aminotransferase, and lactate dehydrogenase levels, as well as azotemia, hyperphosphatemia, hypocalcemia, and leukocytosis.

DISCUSSION:

NMS is a rare but potentially fatal reaction associated with neuroleptic drugs. It occurs in approximately 0.07–2.2% of patients treated with neuroleptics. Risk factors include previous episodes, dehydration, agitation, polypharmacy, and the rate and route of neuroleptic administration.

CONCLUSIONS:

An objective causality assessment revealed that fluphenazine was the probable cause of NMS in this patient. There was no reaction associated with thioridazine and/or haloperidol. Clinicians need to be aware of this drug-induced condition and the potential increased risk associated with concurrent use of multiple psychotropics.

Drug fever

Drug fever is a common condition that is frequently misdiagnosed. It is a febrile response that coincides temporally with the administration of a drug and disappears after discontinuation of the offending agent. Drug fever is usually suspected when no other cause for the fever can be elucidated, sometimes after antimicrobial therapy has already been started. In nonsensitized individuals receiving a drug for the first time, the onset of fever is highly variable and differs among drug classes, but most commonly appears after 7-10 days of drug administration and rapidly reverses after discontinuation of the drug. Early diagnosis may reduce inappropriate and potentially harmful and expensive diagnostic and therapeutic interventions. Rechallenge with the offending agent will usually cause recurrence of fever within a few hours, confirming the diagnosis. Rechallenge is controversial and should be performed with extreme caution, since there is a potential for a more severe drug reaction. We describe the mechanisms in the pathophysiology of drug fever and summarize the results of published case reports on the wide variety of agents that are implicated in causing drug fever. Special attention is paid to the role of antimicrobial agents in drug fever.

Approach to the febrile patient in the ICU

Fever is a normal adaptive brain response to infectious and noninfectious causes involving a cytokine-mediated response, the generation of acute phase reactants, and the activation of numerous physiologic, endocrinologic and immunologic systems. Ninety percent of patients with severe sepsis in the intensive care unit (ICU) will experience fever during their hospitalization, while the half of the new detected febrile episodes are of noninfectious origin. In the ICU, fever should be treated in cardiorespiratory and neurosurgical patients and in those in whom temperature exceeds 40 degrees C (104 degrees F). Antipyretic therapy must be justified regardless of the metabolic cost (if fever exceeds its physiologic benefit), the result (if the symptomatic relief adversely affects the course of the febrile illness) and the side effects.

Neuroleptic malignant syndrome from central nervous system insult: 4 cases and a novel treatment strategy. Clinical article

Neuroleptic malignant syndrome (NMS) is a potentially life-threatening entity characterized by hyperthermia, autonomic deregulation, decreased mental status, increased muscle tone, and, frequently, by renal failure due to rhabdomyolysis. Classically, it follows administration of antipsychotic medication. The authors report on 4 patients (2 children and 2 adults) in whom NMS was diagnosed after a CNS insult. No patient was receiving antipsychotic medication. The patients' hospital and clinic charts, radiographic data, and follow-up telephone conversations were reviewed retrospectively. All 4 patients met diagnostic criteria for NMS. Three patients presented with shunt failure, and 1 patient had undergone a functional hemispherectomy 2 days earlier. One patient with shunt failure received the diagnosis retrospectively. An endoscopic third ventriculostomy alleviated his shunt failure and he remains free of NMS. The other 2 patients underwent treatment for shunt failure, but NMS remained. These 2 patients and the one who had undergone hemispherectomy underwent a trial of intrathecal baclofen, and the NMS resolved. Subsequently, an intrathecal baclofen infusion device was placed in all 3 patients, and the NMS resolved. The 2 patients in shunt failure had a lumbar intrathecal baclofen infusion device. The patient who had undergone hemispherectomy had an intracranial baclofen catheter. Neuroleptic malignant syndrome is a rare, life-threatening disorder that can occur without the administration of neuroleptic medications. Alleviation of any CNS insult is the first order of treatment. Some patients with persistent symptoms of NMS may benefit from intrathecal delivery of baclofen.

Olanzapine-induced neuroleptic malignant syndrome in a patient with paranoid schizophrenia

A case of a male patient with schizophrenic illness who developed neuroleptic malignant syndrome (NMS) following treatment with olanzapine is reported. Although typical neuroleptics are more frequently associated with NMS, atypical antipsychotics may also cause NMS. Case reports have been published concerning NMS and clozapine,(1) risperidone(2) and olanzapine.(3-6) This case report emphasizes the importance of being cautious when rapidly increasing doses of olanzapine are used in patients with psychiatric illnesses.

Guidelines for evaluation of new fever in critically ill adult patients: 2008 update from the American College of Critical Care Medicine and the Infectious Diseases Society of America

OBJECTIVE

To update the practice parameters for the evaluation of adult patients who develop a new fever in the intensive care unit, for the purpose of guiding clinical practice.

PARTICIPANTS

A task force of 11 experts in the disciplines related to critical care medicine and infectious diseases was convened from the membership of the Society of Critical Care Medicine and the Infectious Diseases Society of America. Specialties represented included critical care medicine, surgery, internal medicine, infectious diseases, neurology, and laboratory medicine/microbiology.

EVIDENCE

The task force members provided personal experience and determined the published literature (MEDLINE articles, textbooks, etc.) from which consensus was obtained. Published literature was reviewed and classified into one of four categories, according to study design and scientific value.

CONSENSUS PROCESS

The task force met twice in person, several times by teleconference, and held multiple e-mail discussions during a 2-yr period to identify the pertinent literature and arrive at consensus recommendations. Consideration was given to the relationship between the weight of scientific evidence and the strength of the recommendation. Draft documents were composed and debated by the task force until consensus was reached by nominal group process.

CONCLUSIONS

The panel concluded that, because fever can have many infectious and noninfectious etiologies, a new fever in a patient in the intensive care unit should trigger a careful clinical assessment rather than automatic orders for laboratory and radiologic tests. A cost-conscious approach to obtaining cultures and imaging studies should be undertaken if indicated after a clinical evaluation. The goal of such an approach is to determine, in a directed manner, whether infection is present so that additional testing can be avoided and therapeutic decisions can be made.

Neuroleptic Malignant Syndrome Associated with Colon-Cancer

Neuroleptic malignant syndrome (NMS), a potentially hazardous side effect of antipsychotic agents, usually develops within 10 days after receiving these agents. We describe a 65-year-old male who developed NMS after taking neuroleptics for alcohol dependence syndrome for several years. He was successfully treated by stopping these agents but three months later, an advanced sigmoid colon cancer was detected. He underwent surgery and the clinical course was uneventful. The present case is rare in that he developed NMS after long-term neuroleptic therapy and concurrent alimentary tract malignancy can be a risk factor for the development of NMS.

The postoperative cardiovascular arrest of a 5-year-old male: an initial presentation of Duchenne's muscular dystrophy

Anesthesia may be administered to patients with Duchenne's muscular dystrophy, but cases are reported in which apparently healthy children suffer hyperkalemic cardiac arrest. We present the case of a 5-year-old boy whose muscular dystrophy was discovered following a fatal, perioperative cardiac arrest in the postanesthesia care unit.

The evaluation and management of patients with neuroleptic malignant syndrome

NMS is a rare but fatal syndrome that needs to be considered in the perioperative period. Although many aspects remain unexplored and controversial, with greater awareness of the condition, new concepts are coming into light. Definitive treatment guidelines remain an important issue to be addressed. Efforts have been initiated in that direction and all cases can be reported on a toll-free hotline ( 1-888-667-8367) or online (www.nmsis.org).

[Rhabdomyolysis and myoglobinuria]

Rhabdomyolysis is a disorder characterized by acute damage of the sarcolemma of the skeletal muscle leading to release of potentially toxic muscle cell components into the circulation, most notably creatine phosphokinase (CK) and myoglobin, and is frequently accompanied by myoglobinuria. Therefore, the term myoglobinuria is often used interchangeably with the term rhabdomyolysis. This disorder may result in potential life-threatening complications such as acute myoglobinuric renal failure, hyperkalemia and cardiac arrest, disseminated intravascular coagulation, and compartment syndrome. The condition is etiologically heterogeneous and may result from a large variety of diseases affecting muscle membranes, membrane ion channels, and muscle energy supply including acquired causes (e.g., exertion, crush injury and trauma, alcoholism, drugs, and toxins) and hereditary causes (e.g., disorders of carbohydrate metabolism, disorders of lipid metabolism, or diseases of the muscle associated with malignant hyperthermia). In many patients with idiopathic recurrent rhabdomyolysis, specific inherited metabolic defects have not been recognized up to now.

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.

Malignant syndrome in Parkinson's disease: concept and review of the literature

We reviewed literature on malignant syndrome occurring in patients with Parkinson's disease (PD) during the course of drug therapy. Clinical features were high fever, marked rigidity, consciousness disturbance, autonomic dysfunction, and elevation of serum creatine kinase. The clinical features were essentially similar to those of neuroleptic malignant syndrome. The immediate triggering event was, most often, discontinuation or reduction of anti-parkinsonian drugs, particularly of levodopa. But no anti-parkinsonian drug was the exception to the induction of malignant syndrome. Serious complications were severe pneumonia, disseminated intravascular coagulation, and acute renal failure. Early treatment with intravenous fluid infusion and external body cooling are essential for good recovery. Bromocriptine and dantrolene sodium were used frequently. It has been claimed that they are effective; however, randomized controlled studies are needed to explicitly prove the efficacy of these drugs in malignant syndrome associated with PD.

Rhabdomyolysis: a review

Rhabdomyolysis, a syndrome of skeletal muscle breakdown with leakage of muscle contents, is frequently accompanied by myoglobinuria, and if sufficiently severe, acute renal failure with potentially life-threatening metabolic derangements may ensue. A diverse spectrum of inherited and acquired disorders affecting muscle membranes, membrane ion channels, and muscle energy supply causes rhabdomyolysis. Common final pathophysiological mechanisms among these causes of rhabdomyolysis include an uncontrolled rise in free intracellular calcium and activation of calcium-dependent proteases, which lead to destruction of myofibrils and lysosomal digestion of muscle fiber contents. Recent advances in molecular genetics and muscle enzyme histochemistry may enable a specific metabolic diagnosis in many patients with idiopathic recurrent rhabdomyolysis.

[Malignant hyperthermia susceptibility in 3 patients with malignant neuroleptic syndrome]

Hyperthermia, skeletal muscle rigidity, rhabdomyolysis, acidosis and multiple system insufficiency characterize malignant hyperthermia. Anaesthetic malignant hyperthermia follows halogenated volatile agents and/or depolarizing muscle relaxants utilization. Diagnosis is based on in vitro muscle contracture in response to halothane and/or caffeine exposure. Neuroleptic malignant syndrome affects patients taking neuroleptic drugs; clinical findings include hyperthermia, extrapyramidal rigidity, acidosis, neurovegetative instability and neurological signs. We report three neuroleptic malignant syndrome patients with positive muscle contracture tests which shows that muscle from neuroleptic malignant syndrome patients may in some instances show alterations similar to those of anaesthetic malignant hyperthermia.

Muscle changes in the neuroleptic malignant syndrome

AIMS

To characterise the skeletal muscle changes in the neuroleptic malignant syndrome (NMS).

METHODS

Detailed light and ultrastructural examination was carried out on skeletal muscle from three cases of NMS, two associated with recreational drugs (3,4-methlenedioxymethylamphetamine (MDMA, Ecstasy) and lysergic acid diethylamide (LSD)) and one with antipsychotic drugs (fluoxetine (Prozac) and remoxipride hydrochloride monohydrate (Roxiam)).

RESULTS

The muscles were grossly swollen and oedematous in all cases, in one with such severe local involvement that the diagnosis of sarcoma was considered. On microscopy, there was conspicuous oedema. In some fascicles less than 10% of fibres were affected whereas in others more than 50% were pale and enlarged. There was a spectrum of changes: tiny to large vacuoles replaced most of the sarcoplasm and were associated with necrosis. A striking feature in some fibres was the presence of contraction bands separating segments of oedematous myofibrils. Severe endomysial oedema was also detectable. There was a scanty mononuclear infiltrate but no evidence of regeneration.

CONCLUSIONS

The muscle changes associated with NMS are characteristic and may be helpful in differential diagnosis.

Local anesthesia and malignant hyperthermia: review of the literature and recommendations for the dermatologic surgeon

BACKGROUND

Malignant hyperthermia (MH) is a rare syndrome that is a major cause of anesthetic-related morbidity and mortality in otherwise well patients. The role of local anesthetics, stress, and epinephrine in inducing this syndrome has been subjected to controversy.

OBJECTIVE

To examine the role of local anesthetics, stress, and epinephrine in producing clinically relevant adverse effects in patients with MH.

METHODS

A critical review of the literature.

RESULTS

Local anesthesia is safe for use in usual doses in MH-susceptible patients. The role of stress and epinephrine in precipitating episodes of MH is likely minimal, but controversy remains in the anesthesia and dental literature.

CONCLUSION

Recommendations for diagnosis, treatment, and safety precautions to be taken by dermatologic surgeons when treating MH patients are made.

Differential diagnosis of thyroid crisis and malignant hyperthermia in an anesthetized porcine model

The intra-operative differential diagnosis between thyroid crisis and malignant hyperthermia can be difficult. Also stress alone can trigger MH. The purposes of this study were: 1) to investigate the metabolic and hemodynamic differences between thyroid crisis and MH, 2) determine how thyroid crisis affects the development of MH, and 3) determine if the stress of thyroid crisis can trigger MH in susceptible individuals. We studied MH susceptible and normal swine. Two groups of animals (MH susceptible and normal) were induced into thyroid crisis (critical core hyperthermia, sustained tachycardia and increase in oxygen consumption) by pretreatment with intraperitoneal triiodothyronine (T3) followed by large hourly intravenous injections of T3. Two similar groups were given intravenous T3 but no pretreatment. These animals did not develop thyroid crisis and served as controls. Thyroid crisis did not result in metabolic changes or rigidity characteristic of an acute episode of MH. When the animals were subsequently challenged with MH triggering agents (halothane plus succinylcholine) dramatic manifestations of fulminant MH episodes (acute serious elevation in exhaled carbon dioxide, arterial CO2, rigidity and acidemia) were noted only in the MH susceptible animals. Although thyroid crisis did not trigger MH in the susceptible animals it did decrease the time to trigger MH (14.1 +/- 7.2 minutes versus 47.2 +/- 17.7 minutes, p < 0.01) in susceptible animals. Hormone induced elevations in temperature and possibly other unidentified factors during thyroid crisis may facilitate the triggering of MH following halothane and succinylcholine challenge.

Psychiatric and behavioral problems

In an emergency setting, many neurologic conditions present with psychiatric and behavioral symptoms. These symptoms may either be the first manifestation of the neurologic illness or a later occurrence in the progression of the disease. It is important for clinicians evaluating patients with psychiatric symptoms to identify the signs indicating associated neurologic illness and to have strategies for managing the acute, potentially dangerous, neuropsychiatric manifestations of the disease. This article addresses emergency evaluation and management of depression, anxiety, psychosis, mania, suicide attempts, neuroleptic malignant syndrome and other hypermetabolic and amnestic syndromes, somatoform disorders, aggression, and legal issues, such as capacity to accept or refuse treatment.

Hyperthermia, rhabdomyolysis, and disseminated intravascular coagulation associated with baclofen pump catheter failure

A 29-year-old man with C6 tetraplegia (ASIA A) using an implanted baclofen pump and intrathecal catheter infusion system for spasticity control developed severe spasticity, hyperthermia, hypotension, rhabdomyolysis, and disseminated intravascular coagulation after catheter disconnection. Tracheal intubation and mechanical ventilation were necessary. Extensive workup for a concurrent infection was negative except for urine cultures. The patient remained febrile for 10 days despite empirical antibiotic trials. Administration of high-dose benzodiazepines was inadequate for spasticity control. Spasticity control and his clinical condition, including body temperature, did not improve until his catheter was surgically replaced and intrathecal baclofen administration was resumed. The pharmacopathology of abrupt baclofen withdrawal and the similarities between this presentation, sepsis, neuroleptic malignant syndrome, and malignant hyperthermia are discussed. High-dose dantrolene was not used; however, based on similarities between this patient's presentation and neuroleptic malignant syndrome, it may have been the drug of choice.

The neuroleptic malignant syndrome: a logical approach to the patient with temperature and rigidity

The neuroleptic malignant syndrome is a rare, potentially fatal, adverse reaction to neuroleptic drugs characterised by severe rigidity, high temperature and autonomic dysfunction. In the light of the hypothesized pathophysiology of this condition, a rational approach to the management of patients presenting with temperature and rigidity is provided. The aims of this approach are three-fold: to reduce the incidence of the condition, to be able to recognise it early so as to treat before life-threatening complications arise, and to be able to recognise early those conditions which mimic neuroleptic malignant syndrome, so as not to delay their specific treatment.

Drug-induced hyperthermia

Drug-related causes of hyperthermia can often be overlooked in the setting of elevated body temperature. This article reviews the pathophysiology, presentation, and treatment of several drug-induced hyperthermia syndromes: malignant hyperthermia, neuroleptic malignant syndrome, sympathomimetic poisoning, and anticholinergic toxicity. Although the general approach is similar, specific management strategies may be required for each syndrome.

Development of an animal model for neuroleptic malignant syndrome: heat-exposed rabbits with haloperidol and atropine administration exhibit increased muscle activity, hyperthermia, and high serum creatine phosphokinase level

The neuroleptic malignant syndrome (NMS) is a life-threatening complication of neuroleptic treatment. To elucidate the pathogenesis of NMS, an animal model has been developed. Experimental rabbits treated with haloperidol (1 mg/kg) by intramuscular injection, were studied for the diagnostic symptoms of increased muscle rigidity, elevated body temperature, and high serum creatine phosphokinase (CPK) level. Administration of haloperiodol (1 mg/kg) and atropine (0.4 mg/kg), and exposure to high ambient temperature (35 degrees C) induced a significant increase in electromyographic activity with muscle rigidity similar to that observed in patients with NMS. Such rabbits also showed elevated body temperature and serum CPK value. In addition to the similarity of the signs and symptoms, all parameters measured (muscle rigidity, body temperature, and serum CPK level) were normalized by dantrolene treatment. The effectiveness of dantrolene in the experimental animal partially confirms the validity of this animal model for NMS. This experimental animal model for NMS may be useful to elucidate the pathogenesis of NMS.

Hyponatremia, convulsions and neuroleptic malignant syndrome in a male with schizoaffective disorder

OBJECTIVE

The aim of the study was to highlight the diagnostic difficulties occurring when hyponatremia presents concurrently with neuroleptic malignant syndrome (NMS). Diagnostic issues in the differentiation between hyponatremia and NMS are discussed.

CLINICAL PICTURE

A case of dilutional hyponatremia (DH) secondary to psychogenic polydipsia (PP) associated with NMS occurring in a male with schizoaffective disorder is described. The clinical picture was complicated by convulsions, perhaps due to clonazepam withdrawal and possible lithium toxicity.

TREATMENT

The patient was treated with supportive medical measures.

OUTCOME

The patient made a full recovery.

CONCLUSIONS

Hyponatremia and NMS have been found to be associated. This association may be due to an undefined common pathogenesis, or may be coincidental. Hyponatremia may also hinder the diagnosis of NMS.

Neuroleptic malignant syndrome in a trauma patient

Neuroleptic malignant syndrome is a rare complication of antipsychotic medications. This paper describes the case of a trauma patient who received haloperidol and droperidol for severe agitation, developed neuroleptic malignant syndrome, and was treated successfully with dantrolene sodium, and also provides a review of the literature.

Hyperpyrexia associated with sustained muscle contractions: an alternative diagnosis to central fever

Muscle activity is the principal source of body heat production, and elevated core body temperatures may occur in healthy exercising persons. Hyperpyrexia from sustained tonic muscle contractions can also occur in a number of pathological conditions. The present case of hyperpyrexia associated with dystonic posturing and sustained muscle contraction in a child with encephalopathy illustrates the importance of recognizing muscular activity in the generation of fever of unknown origin following central nervous system injury. The pathophysiology, clinical features, and management of this uncommon cause of fever are discussed.