Successful Diagnosis of Neuroleptic Malignant Syndrome in an Unconscious Patient Using Amplitude-Integrated Electroencephalography: A Case Report

Neuroleptic malignant syndrome (NMS) is a rare but life-threatening medical condition often characterized by altered consciousness and clinical features resembling seizures. This case report presents a unique and successful diagnosis of NMS in an unconscious patient with an unknown medical history. We demonstrate the potential utility of amplitude-integrated electroencephalography (aEEG) as a valuable tool for the differential diagnosis of seizure-like medical conditions, including NMS. The application of aEEG allowed for early diagnosis and prompt initiation of appropriate treatment, potentially contributing to improved patient outcomes.

What clinical analysis of antipsychotic-induced catatonia and neuroleptic malignant syndrome tells us about the links between these two syndromes: A systematic review

OBJECTIVES

Antipsychotic-induced catatonia (AIC) and neuroleptic malignant syndrome (NMS) are life-threatening adverse reactions to antipsychotic medication. We conducted a systematic review of literature following the PRISMA statement guidelines to obtain a description of these syndromes (population, context of occurrence, antipsychotic agents implicated) and draw conclusions about their links.

METHODS

We searched Medline and Web of science databases from January 1951 to May 2019 (further restricted from 2000 to 2019) using search terms including "catatonia", "neuroleptic malignant syndrome" and "antipsychotic agents" for case reports, case series and analytic studies. After screening 4082 records, 410 full-text articles (describing 555 events) were assessed for eligibility. We included events of AIC and/or NMS according to Diagnostic and Statistical Manual (DSM) criteria and extracted data about patients' characteristics, context of occurrence, antipsychotic agent(s) involved and treatment outcomes.

RESULTS

We included 165 events (16 AIC, 129 NMS and 20 AIC + NMS) from 144 case reports and case series. The most reported diagnosis was schizophrenia. Comorbid pre-existing conditions such as central nervous system diseases and acute medical events were common. Most of the events (63.3 %) occurred during antipsychotic monotherapy. Second-generation antipsychotics (SGAs, 63.8 %) were overall more implicated than first-generation antipsychotics (FGAs, 36.2 %).

DISCUSSION

Our findings highlight that any antipsychotic medication, even SGA monotherapy prescribed at recommended dose, is at risk for these side effects. FGAs and polypharmacy seem to represent risk factors for malignant catatonia in AIC. The clinical overlap observed between AIC and NMS events in our review suggests a clinical continuum between catatonia and NMS.

A fatal case of fulminant neuroleptic malignant syndrome: A case report

Background

Neuroleptic malignant syndrome (NMS), a rare but potentially life-threatening adverse reaction to treatment with antipsychotic drugs, is characterized by hyperthermia, muscle rigidity, impaired consciousness, and autonomic disturbances. Some reports have described rapidly progressing cases of NMS resulting in death within several days. This report describes a clinical course of fatal and fulminant NMS in a patient with schizoaffective disorder.

Case Presentation

A 67-year-old man had long been in a stable condition under antipsychotic pharmacotherapy. At 3 days before admission to our hospital, he complained of diarrhea, fatigue, and reduced appetite. On admission to our hospital, he showed fever, mild muscle rigidity at the four extremities, elevated heart rate, hypertension, excessive diaphoresis, and decreased percutaneous oxygen saturation (SpO2). He was diagnosed as having NMS. Within 3 days after the onset of NMS, he displayed severe hyperthermia up to 41.4°C and severe autonomic disturbances, including elevated heart rate and hypertension. Despite treatments with dantrolene and bromocriptine, he went into shock and died on the fourth day after admission.

Conclusion

The present case suggests that severe hyperthermia and severe autonomic disturbances at the early stage of the onset might be signs of fatal and fulminant NMS. It may be recommended that clinicians consider electro-convulsive therapy when treating fulminant NMS with these symptoms.

Neuroleptic malignant syndrome as part of an akinetic crisis associated with sepsis in a patient with Lewy body disease

A 65-year-old Japanese woman with Parkinson's disease, later diagnosed with Lewy body disease, presented with a 2-day history of systemic tremors. She also had fever without rigidity or creatine kinase (CK) elevation. She was diagnosed with sepsis caused by pyelonephritis with acute kidney injury and parkinsonism exacerbation. Although antibiotic and fluid therapy improved her pyuria and renal function, her fever and tremors persisted. On the fourth day, her symptoms worsened and resulted in cardiopulmonary arrest; however, quick resuscitation allowed the return of spontaneous circulation. Simultaneously, hyperthermia, altered consciousness, extrapyramidal symptoms, dysautonomia and CK elevation were noted. Thus, dantrolene administration was initiated with a tentative diagnosis of neuroleptic malignant syndrome (NMS). This caused her fever to subside, and her symptoms gradually improved. It was difficult to distinguish between parkinsonism exacerbation associated with sepsis and NMS. Physicians should consider NMS early on, even if the patient does not fulfil the diagnostic criteria.

Neuroleptic Malignant Syndrome: No Longer Exclusively a “Neuroleptic” Phenomenon

Objective:

To review the literature concerning the incidence of neuroleptic malignant syndrome (NMS) associated with the use of atypical antipsychotics.

Data Sources:

Cases were identified through a search of MEDLINE (1986–March 2004) using the terms neuroleptic malignant syndrome, antipsychotic, clozapine, risperidone, olanzapine, quetiapine, ziprasidone, and aripiprazole.

Study Selection and Data Extraction:

Case reports of possible NMS secondary to second-generation antipsychotics were selected for review. Reports meeting the Diagnostic and Statistical Manual of Mental Disorders, 4th edition, criteria for NMS were considered. Case reports in which 1 of the 2 major diagnostic criteria was met were also included in the analysis. Furthermore, at least one minor criterion was met. Case reports in which patients received traditional antipsychotics were excluded.

Data Synthesis:

NMS is a rare and sometimes fatal disease. Several theories exist as to how NMS develops, and an equally large amount of diagnostic criteria are available. However, the majority of available data are based on the first-generation neuroleptics and very few exist with regard to the second-generation antipsychotics.

Conclusions:

Although there are numerous case reports of NMS occurring secondary to the use of second-generation antipsychotics, the incidence has never been fully elucidated. While the reasons for this remain uncertain, not all cases of second-generation–induced NMS fulfill the diagnostic criteria established for traditional neuroleptics and therefore may not be reported as such.

Acute Dystonic Reaction and the Neuroleptic Malignant Syndrome

Up to 90% of patients on chronic antipsychotic therapy will experience adverse neurologic side effects, with many of these effects attributable to the dopamine-blocking properties of these drugs. Even the newer, “atypical” antipsychotics are increasingly associated with neurologic complications. In the acute care setting, these medications have broad application beyond the management of psychiatric illness. Given the extent of their use, clinicians should be familiar with the spectrum of neurological syndromes that can develop. Some are common, such as akathisia, acute dystonic reaction, tardive dyskinesia, and drug-induced parkinsonism. Others, such as the life-threatening neuroleptic malignant syndrome, are rare yet must be recognized early to affect survival and improve outcome. This discussion highlights 2 idiosyncratic syndromes, acute dystonic reaction and neuroleptic malignant syndrome. The differential diagnosis for both syndromes and their management is discussed.

Catatonia & neuroleptic malignant syndrome

The relationship between catatonia and neuroleptic malignant syndrome (NMS) has, in the last three decades, generated considerable interest and controversies. This article provides a critical overview of our understanding of the relationship between the two enigmatic syndromes. It examines various conceptualizations of NMS, published data supporting a close relationship between the two syndromes, hypotheses proposed and controversies generated regarding how the two are related, and the clinical and pathophysiological implications of the relationship.

Retrospective chart review on exposure to psychotropic medications associated with neuroleptic malignant syndrome

OBJECTIVE

To investigate the association between neuroleptic malignant syndrome (NMS) and levels of antipsychotic exposure.

METHOD

Electronic health record data systematically screened from a large mental health service provider in southeast London provided 67 NMS cases which were individually matched with 254 controls on age, gender, and primary psychiatric diagnosis. Data on psychotropic agents, combinations, dose, and dose change of antipsychotic prescriptions over the preceding 5 (oral agents) or 15 days (depot agents) were extracted and compared between groups using conditional logistic regression models.

RESULTS

NMS was associated with higher number of antipsychotic agents used, use of first-generation agents or aripiprazole, use of first-generation agents only or cross-generation agents, and higher mean and maximum daily doses. In further analyses, associations with antipsychotics type remained significant when adjusted for dose, but those with dose were attenuated following adjustment for type. The specific use of haloperidol, aripiprazole, depot flupentixol, and benzodiazepines was independently associated with NMS. Non-white ethnicity was also found to be associated with NMS.

CONCLUSION

NMS was primarily associated with type of antipsychotic and polypharmacy rather than overall dose. Variation in risk by ethnicity requires further research.

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.

Ascertaining instances of neuroleptic malignant syndrome in a secondary mental healthcare electronic medical records database: the SLAM BRC Case Register

OBJECTIVES

Neuroleptic malignant syndrome (NMS) is a rare but potentially fatal complication of antipsychotic treatment. However, there is no single diagnostic test and a variety of overlapping criteria exist. Using a large case register of secondary mental healthcare in Southeast London, we aimed to identify suspected cases and quantify the levels of agreement between six different diagnostic criteria previously published.

METHODS

Taking advantage of a recently developed case register sourced from full but anonymized electronic medical records (the South London and Maudsley NHS Foundation Trust), we applied text string searching to identify suspected NMS cases for which action had been taken to investigate or treat. Three psychiatrists manually reviewed case records for clinical data to compare diagnostic criteria.

RESULTS

Analysis of the case register revealed 183 suspected NMS cases, of which 43 fulfilled at least one set of the six diagnostic criteria. Agreement between criteria was poor (κ = 0.35 for all combined agreement; 95% confidence interval 0.31-0.39) and only one case fulfilled all six diagnostic criteria. However, among cases meeting any diagnostic criteria, pyrexia, extrapyramidal symptoms, altered consciousness, autonomic symptoms, and elevated CK concentrations were significantly more common than in cases not meeting diagnostic criteria (p < 0.01). On further analyses, the presence of two or more of these features significantly distinguished cases meeting criteria from those that did not (p < 0.01). Individual symptoms were also reported in suspected cases of NMS that did not fulfil any diagnostic criteria.

CONCLUSIONS

In a large sample of NMS cases recorded in medical records, relatively poor agreement was found among published diagnostic criteria for NMS. However, core features of NMS were observed significantly more often among cases meeting diagnostic criteria. Individual symptoms were also described in suspected cases that did not meet diagnostic criteria. These findings suggest a continued need for consensus on standard criteria for NMS.

Recognizing neuroleptic malignant syndrome in the emergency department: a case study

PURPOSE

A case study is presented to discuss the importance of accurate assessment of a patient in the emergency department (ED) who develops neuroleptic malignant syndrome (NMS).

CONCLUSIONS

There has been a significant increase in the number of patients with psychiatric emergencies seeking treatment in the ED. The most frequently used medication for treating these patients is a high-potency typical antipsychotic (neuroleptic). Although NMS is a rare condition, it is a potentially fatal complication of neuroleptic medications.

PRACTICE IMPLICATIONS

Early identification of this potentially life-threatening syndrome will lead to prompt treatment and improve the care of this vulnerable population.

Catatonia as a risk factor for the development of neuroleptic malignant syndrome: report of a case following treatment with clozapine

Catatonia is characterized by the predominance of psychomotor abnormalities and shares many clinical, biological and treatment response features with the neuroleptic malignant syndrome (NMS), a rare adverse reaction to psychoactive medications. It has been advocated that the two conditions should be placed along the same spectrum of disorders. A case of a 49-year-old woman, who developed NMS while on low dose clozapine soon after recovering from catatonia, is presented. The potential relationship between catatonia and NMS is discussed in the light of the existing literature, and attention is drawn to the risk for clozapine-induced NMS in catatonic patients.

Neuroleptic malignant syndrome associated with atypical antipsychotic drugs

Neuroleptic malignant syndrome (NMS) is a rare but potentially severe idiosyncratic adverse reaction usually seen in the context of treatment with antipsychotic drugs. Although NMS is historically associated with the classic or 'typical' antipsychotic drugs, it is also a potential adverse effect of atypical antipsychotic drugs. The widespread use of atypical antipsychotic drugs highlights the need to examine the data relating to the symptomatology, diagnosis, classification and management of NMS with these newer agents. We used MEDLINE and EMBASE to identify NMS case reports and systematic reviews published to June 2008 related to the atypical antipsychotic drugs clozapine, olanzapine, risperidone, paliperidone, aripiprazole, ziprasidone, amisulpride and quetiapine. Case reports and reviews were systematically examined. Our review suggests that, in general, NMS associated with atypical antipsychotic drugs manifests in a typical manner. One notable exception is clozapine-induced NMS, which appears less likely to manifest with extrapyramidal features, including rigidity and tremor. The available literature highlights the divergence of opinion relating to the core diagnostic features of NMS and its conceptualization as a categorical versus dimensional disorder. Both these issues have relevance for the identification of atypical or milder forms of NMS, which are sometimes seen with atypical antipsychotic drugs.

Neuroleptic malignant syndrome: risk factors, pathophysiology, and treatment

Neuroleptic malignant syndrome (NMS) is associated with the administration of antipsychotic agents and other drugs such as l-dopa, antidepressants, and antihistaminic agents. Unexpected changes in mental status, new-onset catatonia, episodic tachycardia, tachypnea, hypertension, dysarthria, dysphagia, diaphoresis, sialorrhea, incontinence, low-grade temperature elevations, and rigidity should arouse suspicion. Several lines of evidence provide support for the involvement of dopamine. Most of the drugs implicated in NMS are D2 dopamine receptor antagonists. Central noradrenergic activity is also possibly related to the disorder, as sympathetic hyperactivity is associated with the active phase of NMS. Currently, the definitive role of GABA deficiency in NMS is yet to be established. Differential diagnosis should include malignant hyperthermia, lethal catatonia, lithium toxicity, serotonin syndrome, and heat stroke. A high degree of suspicion and the discontinuation of antipsychotic agents even if the diagnosis is not established are essential for the safety of the patient. Treatment of NMS should be individualized and be based empirically on the character, duration, and severity of the clinical signs and symptoms noted. The initial step in the treatment of NMS is the removal of the offending agent. Full-blown NMS is a serious condition and requires immediate supportive, nutritive, and electrolyte therapies. The administration of drugs that can improve NMS, such as IV dantrolene and/or oral bromocriptine, may also be taken into consideration, based on the severity and nature of the NMS.

Serum creatine kinase levels in untreated hospitalized adolescents during acute psychosis

OBJECTIVE

Psychosis-associated creatine kinase (CK)-emia (PACK) is a common and pronounced laboratory abnormality that accompanies adult psychotic conditions. Adult PACK is a relatively consistent individual trait. The authors investigated whether psychotic adolescents also present with such PACK characteristics.

METHOD

Participants were 127 newly admitted, drug-free, psychotic Israeli adolescents. Measures were baseline psychotic severity, serum creatine kinase (CK0), lactate dehydrogenase (LDH0), glutamate oxaloacetate transaminase (SGOT0), white blood cell count (WBC0), urine myoglobulin, and the repeated CK (RepCK) measurements taken during recurrent psychotic episodes.

RESULTS

Schizophrenia was the prevalent diagnosis (53%). CK0 levels did not correlate with the severity of the psychotic symptoms. Twenty-one percent of patients had a CK0 level >1,000 IU/L. CK0 and RepCK levels were higher in males than in females (p < or = .001) and in Jewish Sephardi patients than in Ashkenazi patients (p < .007). There was no difference by diagnosis. Logarithmic (Ln) CK0 correlated with RepCK, SGOT0, LDH0, and WBC0 (r = +0.32-0.74, p < .001) but correlated inversely with serum cholesterol0 (r = -0.36, p = .002) in males. Even prominent PACK was not associated with myoglobinuria. These findings remained significant among the younger patients (aged <18 years). In males from this subgroup, LnCK0 also correlated with age (p < .007) but not with weight.

CONCLUSIONS

In psychotic adolescents, PACK is common, is more prevalent among males, is independent of diagnosis, is influenced by ethnicity, and tends to recur.

Electroconvulsive treatment of neuroleptic malignant syndrome: a review and report of cases

OBJECTIVE

Neuroleptic malignant syndrome (NMS) is a potentially lethal adverse effect of neuroleptic medication, with no satisfactory treatment currently available. Electroconvulsive therapy (ECT) has been anecdotally reported to be effective in its treatment. We review 45 published case reports of ECT for NMS and describe nine new cases, to examine its effectiveness, the likelihood of adverse reactions, and the theoretical implications of such treatment.

METHOD

The authors used Medline to identify reports in the English literature where ECT was used in cases of suspected NMS. In addition, the charts of patients referred to the second author for treatment of NMS were reviewed and cases in which ECT used were identified.

RESULTS

The case reports suggest that ECT is effective in many individuals with NMS, even when drug therapy has failed. The response is usually apparent after a few treatments, generally up to six. The response is not predictable on the basis of age, gender, psychiatric diagnosis or any particular feature of NMS including catatonia. Electroconvulsive therapy is a relatively safe treatment in NMS, although the risk of cardiovascular complications should be considered. Malignant hyperthermia due to the anaesthesia associated with ECT has not been reported in patients with NMS, and succinylcholine has been used safely with the exception of one report of fever and raised creatine kinase levels and another report of hyperkalemia.

CONCLUSIONS

Electroconvulsive therapy is the preferred treatment in severe NMS, cases where the underlying psychiatric diagnosis is psychotic depression or catatonia, and in cases where lethal catatonia cannot be ruled out. The effectiveness of ECT for the treatment of NMS has theoretical implications for the relationship between NMS and catatonia, and the possible pathophysiological mechanisms that underlie these disorders.

Droperidol-induced neuroleptic malignant syndrome

A 21-year-old female was admitted to the general medical wards via casualty with a suspected overdose of unknown amounts of procyclidine, diazepam and alcohol. She had been a known intravenous drug addict for 3 years.

On examination she was drowsy, agitated and smelling of alcohol. She had venepuncture sites in her antecubital fossae. Her cardiorespiratory observations were normal and her abdomen was soft and non-tender. Glasgow Coma Score was 9 (E4, M4, V1). Her pupils were dilated but equal and reacting to light. Her tone was normal, as was her temperature. Investigations revealed a normal urea and electrolyte screen and a normal full blood picture. Drug screen was positive for benzodiazepines but negative for paracetamol, salicylates, opiates and amphetamines. Electrocardiography showed a sinus rhythm.

She was initially treated with flumazenil 500 μg intravenously and naloxone 1.6 mg intravenously with some improvement in her conscious state. She was given droperidol 10 mg intramuscularly (IM) for agitation and was admitted to a medical ward.

Two days after admission she was increasingly unmanageable, requiring two staff members to control her at all times. She was having auditory and visual hallucinations and was restless. Further droperidol 10 mg IM was given. At this stage, cardiorespiratory observations were still normal, as was temperature. Pupils were dilated, equal and slow to react. Tone was normal. She was reviewed by the psychiatrists who diagnosed drug-induced psychosis, secondary to procyclidine. She was given further droperidol 30 mg IM and transferred to the psychiatric ward for observation. She developed an acute dystonic reaction which was treated with a total of 20 mg of procyclidine IM.

By day 3 she was sweaty, rigid and psychotic. Her temperature was 37.4°C, with a pulse rate of 120 and arterial pressure of 140/90 mm Hg. She was noted to have extensive bruising over her arms and legs. Creatinine phosphokinase was elevated at 1597 mmol/litre (normal < 170 mmol/litre).

During that evening she became tachycardic (pulse 140 beats per minute), hypotensive (blood pressure 50/30 mmHg), tachypnoeic (respiratory rate 50 breaths per minute) and hyperpyrexial, and was found to have a rectal temperature of 42°C. Her pupils were dilated, equal and reacting but she had generalized increased tone and was vasoconstricted. An arrest call was put out and after initial resuscitation she was rapidly transferred to the surgical intensive therapy unit, with a presumed diagnosis of neuroleptic malignant syndrome.

She was intubated and ventilated with 100% oxygen, and received a total of 120 mg dantrolene intravenously. Active cooling measures were initiated. Over several hours her temperature dropped from 42°C to 36.1°C. She was noted to be oliguric (urine output ≈10 ml/hr) with blood-stained urine, positive for myoglobin. She was oozing from venepuncture sites and had a coagulation screen consistent with acute fulminant disseminated intravascular coagulation (prothrombin time 34 secs (normal 12–14 secs), fibrinogen level 1.8 g/litre (normal 2.5–4 g/litre), platelets 100x109/litre (normal 150–400×109/litre), D-Dimer >8 mg/litre (normal <0.5 mg/litre), haemoglobin 99 g/litre (normal 110–115 g/litre)). She had a marked metabolic acidosis (H+ 49 mmol/litre (normal 36–43 mmol/litre) (base excess -10)). Her potassium was normal. Her urea and creatinine were 10.6 mmol/litre and 259 μmol/litre respectively (normal 2.5–7.5 mmol/litre and 40–130 μmol/litre). An infective screen was normal. She continued to deteriorate rapidly, despite inotropic support, volume replacement, frusemide infusion and transfusion of fresh frozen plasma, platelets and concentrated red cells.

Early next morning (day 4) she was diagnosed as having multisystem organ failure and developed fixed dilated pupils, the latter presumed due to cerebral haemorrhage. Active treatment was withdrawn and she died shortly afterwards. A post-mortem showed pulmonary oedema but no apparent cerebral haemorrhage.

Clozapine-associated neuroleptic malignant syndrome: two new cases and a review of the literature

BACKGROUND

Clozapine has recently been found to be associated with neuroleptic malignant syndrome (NMS). Our objective is to determine if clozapine causes NMS, if the presentation of clozapine-induced NMS differs from that of traditional agents, and which set of diagnostic criteria will most readily allow diagnosis of NMS associated with clozapine.

METHODS

Two new cases of clozapine-associated NMS are presented, along with previously reported cases from the literature, identified by using a MEDLINE search (1966-August 1998). From all cases, concomitant medications and washout periods were examined (if available) to assess clozapine as the likely cause of NMS. Characteristics of clozapine and traditional antipsychotic-induced NMS were compared. Different diagnostic criteria for NMS were applied to the cases to determine which were more likely to diagnose the syndrome.

RESULTS

Clozapine was deemed a highly probable cause of NMS in 14 cases, a medium probability cause in five cases, and a low probability cause in eight cases. The most commonly reported clinical features were tachycardia, mental status changes, and diaphoresis. Fever, rigidity, and elevated creatine kinase were less prominent than in NMS associated with classical neuroleptics.

CONCLUSIONS

Clozapine appears to cause NMS, although the presentation may be different than that of traditional antipsychotics. Levenson's original and Addonizio's modified criteria were more likely to diagnose NMS than were other criteria. Clozapine-associated NMS may present with fewer clinical features. Limitations are the lack of detailed information provided by many of the case reports and the use of "modified" diagnostic criteria for retrospective diagnosis.

High-dose vitamin E plus vitamin B6 treatment of risperidone-related neuroleptic malignant syndrome

We present a case of a 74-year-old patient with schizoaffective disorder, who developed risperidone-related neuroleptic malignant syndrome. This patient responded satisfactorily to the supportive management and vit E plus vit B6.

Recurrence pattern of serum creatine phosphokinase levels in repeated acute psychosis

BACKGROUND

Elevated serum creatine phosphokinase (CPK)MM level is frequently found in acute psychosis. Theories relate this CPKemia to psychomotor agitation and medication. We hypothesized that psychosis-related CPKemia observed in individual patients is relatively consistent.

METHODS

Ninety psychotic patients were studied; 83% were schizophrenics (Brief Psychiatric Rating Scale scores > or = 40) whose serum CPKMM levels were recorded during two or more different acute psychoses. The serum CPKMM levels used were the maximal levels monitored during the beginning of each hospitalization. The last CPK measurement in a circumscribed period was defined as the index serum CPK level (IndCPK). The mean of all other individual maximal CPK measurements during other psychotic episodes was defined as the average CPK (AvgCPK).

RESULTS

Multiple linear regression analysis showed a significant correlation of natural logarithm (Ln) of (IndCPK with Ln(AvgCPK), as well as with gender (coefficient = .65 and .63, p < .0001 and p < .01, respectively). There were significantly higher IndCPK levels among male patients than among female patients (p < or = .001). A relatively consistent individual pattern of serum CPKMM levels during repeated acute psychotic episodes was observed.

CONCLUSIONS

Serum CPKMM levels and gender were found to be good predictors of maximal serum CPKMM levels during every repeated acute psychotic episode. High IndCPK levels are probably risk factors for neuroleptic malignant syndrome.

Diaphoresis and dehydration during neuroleptic malignant syndrome: preliminary findings

Serum osmolality and its relationship to diaphoresis and polydipsic behavior were examined in a series of 38 episodes of neuroleptic malignant syndrome (NMS) in 29 patients. Clinical variables were associated with significantly higher serum osmolality, and diaphoresis tended to emerge earlier than polydipsia in the course of NMS. The findings of this study are consistent with the hypothesis that, at least in some NMS patients, diaphoresis leads to dehydration followed by physiologically appropriate thirst and increased oral water intake. It appears that intravenous hydration is often necessary to correct the significant free water deficit that can occur during the course of NMS.

Suspected neuroleptic malignant syndrome in a patient receiving clozapine

OBJECTIVE

To report a case of suspected neuroleptic malignant syndrome (NMS) associated with clozapine therapy.

CASE SUMMARY

A 42-year-old schizophrenic man treated with clozapine developed a temperature of 39.5 degrees C, diaphoresis, tachycardia, rigidity, and leukocytosis. His serum creatine kinase concentration was 25 000 U/L. A diagnosis of NMS was made. He was treated with bromocriptine and supportive therapy, and recovered within a week.

DISCUSSION

Despite earlier expectations that clozapine, with a pharmacologic profile differing from that of other antipsychotic medications, might not cause NMS, NMS remains the most likely diagnosis in this case.

CONCLUSIONS

NMS may be a possible complication of clozapine therapy.

Catatonia. II. Treatment with lorazepam and electroconvulsive therapy

Case material and retrospective studies support the use of both lorazepam and ECT in treating catatonia, but few prospective investigations exist and none employ quantitative monitoring of response. In this study we test their efficacy in an open, prospective protocol, and define a "lorazepam test' with predictive value for treatment. Twenty-eight patients with catatonia were treated systematically with parenteral and/or oral lorazepam for up to 5 days, and with ECT if lorazepam failed. Outcome was monitored quantitatively during the treatment phase with the Bush-Francis Catatonia Rating Scale (BFCRS). In 16 of 21 patients (76%) who received a complete trial of lorazepam (11 with initial intravenous challenge), catatonic signs resolved. A positive response to an initial parenteral challenge predicted final lorazepam response, as did length of catatonic symptoms prior to treatment. Neither demographic variables nor severity of catatonia predicted response to lorazepam. Four patients failing lorazepam responded promptly to ECT. It is concluded that lorazepam and ECT are effective treatments for catatonia. The rating scale has predictive value and displays sensitivity to change in clinical status.

Management of suspected neuroleptic malignant syndrome

OBJECTIVE

Neuroleptic Malignant Syndrome (NMS) is a rare but potentially lethal form of drug-induced hyperthermia. The objective of this paper is to provide data regarding early and suspected cases as well as offer guidelines for managing this condition. Knowledge of suspected cases will lead to early recognition and prompt management of this condition in the future.

METHOD

To address the gap in knowledge, we present 2 case reports of patients with early NMS-like symptoms. The case reports are followed by a brief review of the literature on differential diagnoses, risk factors, early signs and treatment data.

CONCLUSIONS

The most rational approach to treating NMS entails a hierarchy of interventions determined by the severity and progression of symptoms.

Acute rhabdomyolysis after concurrent administration of interleukin-2, interferon-alfa, and chemotherapy for metastatic melanoma

BACKGROUND

Acute rhabdomyolysis has been described to occur only rarely after systemic administration of cancer chemotherapy drugs, such as cytarabine and 5-azafluorene. A single case of rhabdomyolysis after treatment with alfa-interferon recently was reported, but to the authors' knowledge, there have been no published cases of clinically relevant rhabdomyolysis after systemic therapy with the other agents.

METHODS

The case of a 28-year-old woman with metastatic melanoma and no known history of neuromuscular disorders who developed severe myalgia followed by acute, extensive rhabdomyolysis with multiorgan failure after concurrent administration of systemic biologic therapy and chemotherapy consisting of alfa-interferon, interleukin-2, cisplatin, vinblastine, and dacarbazine is described.

RESULTS

The patient sustained considerable morbidity requiring hemodialysis and respiratory support but eventually recovered. Review of the literature revealed no reported cases of acute rhabdomyolysis after the systemic administration of these agents with the exception of alfa-interferon.

CONCLUSION

Acute rhabdomyolysis should be considered when evaluating patients receiving similar biochemotherapy regimens, particularly for those regimens that are alfa-interferon-based and for patients who develop myalgia along with evidence of multiorgan failure.

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.

Neuroleptic malignant syndrome

Neuroleptic malignant syndrome is a rare but potentially fatal reaction associated with neuroleptic drugs. It occurs in about 0.2% of patients treated with neuroleptics. Risk factors include previous episodes, dehydration, agitation, and the rate and route of neuroleptic administration. Although NMS has been reported in patients with diverse psychiatric diagnoses, as well as in normal subjects, patients with organic brain disorders or mood disorders, particularly when receiving lithium, may be at increased risk. Standardized criteria for the diagnosis of NMS have been developed and emphasize the classic findings of hyperthermia, muscle rigidity, mental status changes, and autonomic dysfunction. The syndrome lasts 7 to 10 days in uncomplicated cases receiving oral neuroleptics. Treatment consists primarily of early recognition, discontinuation of triggering drugs, management of fluid balance, temperature reduction, and monitoring for complications. Use of dopamine agonists or dantrolene or both should be considered and may be indicated in more severe, prolonged, or refractory cases. Electroconvulsive therapy has been used successfully in some cases and is particularly useful in the post-NMS patient. As a result of these measures, mortality from NMS has declined in recent years although fatalities still occur. Neuroleptics may be safely reintroduced in the management of the majority of patients recovered from an NMS episode, although a significant risk of recurrence does exist, dependent in part on time elapsed since recovery and dose or potency of neuroleptics used. Data drawn from clinical observations and basic studies support the primary role of an acute reduction in brain dopamine activity in the development of NMS. Additional studies of facilitating cofactors may lead to innovative risk-reduction strategies and the development of safer neuroleptic drugs.

Neuroleptic-induced catatonia as a stage in the progression toward neuroleptic malignant syndrome

Neuroleptic-induced catatonia is reported in an adolescent patient who responded successfully to lorazepam. The authors propose five discrete stages toward the progression of neuroleptic malignant syndrome, each with a separate treatment.