Rabies in the critical care unit: diagnostic and therapeutic approaches

Worldwide, human rabies is prevalent where there is endemic dog rabies, but the disease may present unexpectedly in critical care units when suggestive clinical features have passed. In North America transmission from bats is most common and there is often no history of a bat bite or even contact with bats. Laboratory diagnostic evaluation for rabies includes serology plus skin biopsy, cerebrospinal fluid, and saliva specimens for rabies virus antigen and/or RNA detection. Rare patients have survived rabies, and most received rabies vaccine prior to the onset of illness. Therapeutic coma (midazolam and phenobarbital), ketamine, and antiviral therapies (dubbed the "Milwaukee Protocol") were given to a rabies survivor, but this therapy was likely not directly responsible for the favorable outcome. There have been many subsequent failures of similar therapeutic approaches. There is no scientific rationale for the use of therapeutic coma in human rabies. New approaches to treating human rabies need to be developed.     

A case of acute disseminated encephalomyelitis after renal transplantation]

We report a patient of acute disseminated encephalomyelitis (ADEM) in a recipient of renal transplantation. A 43-year-old man suffered from generalized convulsion and consciousness disturbance followed by coma on day 53 of after the transplantation. He was receiving several immunosuppressants, and an increase of serum antigen for cytomegalovirus was observed one day before the ictus. T2 and diffusion-weighted image of MRI showed high intensity lesions in the bilateral cerebral white matter, basal ganglia, thalamus, midbrain, pons and cerebellum. Examination of cerebrospinal fluid revealed elevated myelin basic protein level. The patient was diagnosed as having ADEM and was treated with methylpredonisolone pulse therapy in combination with intravenous immune globulin. He gradually recovered and became capable to eat and sit on a wheel chair. White matter lesions on MRI were also diminished. ADEM may occur in recipients of organ transplantation even if they have immunosuppressive treatment.     

Valproate-induced coma with ketosis and carnitine insufficiency

We observed two patients who developed coma following administration of valproate in dosages of 32 to 40 mg/kg per day. Valproate levels were within the therapeutic range, and results of liver function studies were normal. Both patients had ketosis and adipic aciduria. Plasma free carnitine levels were decreased during coma and after recovery. One patient excreted ethylmalonic acid, butyrylcarnitine, and glutarylcarnitine during and after resolution of coma, suggesting a multiple acyl coenzyme A dehydrogenation defect. Low serum carnitine levels may predispose patients to development of altered consciousness when treated with valproate.     

Treatment of subacute sclerosing panencephalitis with interferon-alpha,ribavirin, and inosiplex

Subacute sclerosing panencephalitis is an almost universally fatal late complication of measles infection for which there is no established treatment. We report a patient with subacute sclerosing panencephalitis who was bed-bound and ataxic and had a left hemiparesis and frequent myoclonus. He was started on a new regimen consisting of intraventricular interferon-alpha (starting at 100,000 U/m2/day, building up to 1 million U/m2/day), ribavirin (60 mg/kg/day intravenously), and inosiplex (3 g/day) and improved markedly. At 10 weeks, the intraventricular reservoir was removed because of bacterial infection, and he was discharged home on oral ribavirin (1200 mg/kg/day) and inosiplex. He continued to improve as judged by neurologic examination, functional independence measurement, neuropsychometry and single photon emission computed tomography (SPECT) imaging. However, after 10 months, he deteriorated suddenly and died before further intraventricular treatment could be instituted. Further trials are needed to evaluate long-term combination therapy in subacute sclerosing panencephalitis.     

Dose-dependent down-regulation of beta-adrenergic receptors after chronic intravenous infusion of antidepressants

1. The effects of intravenous infusion of desipramine (1, 3, 10, and 60 mg/kg/day), amitriptyline, zimelidine, iprindole (3, 10, 30, 60, and 100 mg/kg/day each), imipramine (10, 30, and 100 mg/kg/day), or U-48753E (1, 3, 10, and 30 mg/kg/day) on the density of central beta-adrenergic receptors (beta-AR) were investigated in female Sprague-Dawley rats. 2. Desipramine, amitriptyline, zimelidine, iprindole, imipramine, and U-48753E dose-dependently reduced the density of beta-AR in the cerebral cortex. 3. The time of onset of down-regulation of beta-AR was negatively correlated with the doses of drugs. 4. At equipotent doses, antidepressants seem to have a similar profile for the time of onset of reduction in the density of beta-AR. 5. The results indicate that down-regulation of beta-AR may be involved in mediating the therapeutic effects of antidepressants, and this effect can be rapidly achieved by intravenous infusion of drugs.     

Oral high-dose phenobarbital therapy for early infantile epileptic encephalopathy

We report oral high-dose phenobarbital therapy for a patient with early infantile epileptic encephalopathy with suppression bursts (Ohtahara syndrome). At 1 month of age, many series of tonic spasms, with raising limbs and crying lasting for a few minutes, developed and increased up to approximately 300 times per day. Initially intravenous midazolam (0.5 mg/kg/hour) slightly decreased the seizures, although oral vitamin B6, valproic acid, clonazepam, and zonisamide had little effect. Oral high-dose phenobarbital therapy was begun at a dosage of 15 mg/kg/day, and the seizures markedly decreased to 5-10 times per day and the epileptic discharges on electroencephalogram greatly decreased. Serum phenobarbital levels ranged between 60 and 100 mg/dL. High-dose phenobarbital therapy should be considered for the treatment of early infantile epileptic encephalopathy with suppression bursts.     

Chronic inflammatory demyelinating polyradiculoneuropathy of childhood: treatment with high-dose intravenous immunoglobulin

We treated four children with chronic inflammatory demyelinating polyradiculoneuropathy (CIDP) with high-dose intravenous immunoglobulin (IVIG). All patients received 400 mg/kg of IVIG a day for 5 days during relapses, and one patient received additional periodic infusions of 400 mg/kg. All patients showed excellent recovery of motor strength following each relapse that was treated with IVIG. Compared with plasmapheresis (which was used to treat relapses earlier), recovery of function with IVIG treatments was similar, and in two patients it was superior, to plasmapheresis. There were no side effects with IVIG treatments as compared with plasmapheresis with which two children had infection of central lines with Staphylococcus epidermidis, one had profuse bleeding from accidental extrusion of a central line, and one had multiple episodes of major venous thromboses. High-dose IVIG was a safe and effective adjunctive therapy for childhood CIDP in these four patients.     

A case of steroid-resistant polymyositis who made a good response to high dose intravenous immunoglobulins (IVIG)]

We report a 69-year-old woman with steroid-resistant polymyositis who made a good response to high dose intravenous immunoglobulins (IVIG). She was diagnosed as polymyositis by muscle weakness of her extremities and bulbar muscles, higher level of serum CK and muscle biopsy findings of her biceps brachii muscle. Because of the coexistence of pulmonary tuberculosis and interstitial pneumonia, she was initially treated with 40 mg (1 mg/kg)/day of oral prednisolone, and methylprednisolone pulse therapy 500 mg/day intravenous drip (d.i.v.) x 3 days, 750 mg/day d.i.v. x 3 days. Since her condition deteriorated in spite of these conventional therapies, IVIG therapy 15 g (375 mg/kg)/day d.i.v. x 3 days was administrated. She showed remarkable improvement of serum CK level and muscle strength. Although corticosteroid is the mainstay of therapy for polymyositis, our case study showed that IVIG is also an efficacious therapy for polymyositis, especially resistant to the conventional treatment.     

Treatment of electrical status epilepticus during slow-wave sleep with high-dose corticosteroid

A 4-year-old female patient with epilepsy with continuous spike-and-waves during slow-wave sleep not classified as Landau-Klefner syndrome, refractory to antiepileptic drugs including valproate, benzodiazepines, and lamotrigine, was treated successfully with high-dose intravenous methylprednisolone therapy. Valproate, clobazam, and lamotrigine were continued at the same dose during and after high-dose intravenous corticosteroid therapy. During corticosteroid therapy, awake and sleep electroencephalogram was recorded every day. On day 7, a dramatic clinical and electroencephalographic response was observed. After high-dose intravenous methylprednisolone, prednisolone was administered orally (2 mg/kg daily) for 2 months, then gradually withdrawn. After the withdrawal of corticosteroid therapy, the patient maintained the clinical improvement in behavior, and no continuous spike-and-wave electrical status epilepticus during slow-wave sleep occurred on routine monthly sleep electroencephalogram performed for the last 6 months. In the present case, an add-on high-dose intravenous corticosteroid seems to be effective in the treatment of patients with electrical status epilepticus during slow-wave sleep syndrome, especially when antiepileptic drugs fail.     

The clinical usefulness of high-dose intravenous immunoglobulin therapy for chronic inflammatory demyelinating polyneuropathy and multifocal motor neuropathy]

To explore the optimum dose of intravenous immunoglobulin (i.v.Ig) for treating patients with chronic inflammatory demyelinating polyrneuropathy and multifocal motor neuropathy, we compared the usefulness of i.v.Ig among 3 treatment doses. Fifty-nine patients were randomly divided into three treatment dosage groups: 20 patients for Group I using 50 mg/kg/day x 5 days, 19 patients Group II using 200 mg/kg/day x 5 days, and 20 patients Group III using 400 mg/kg/day x 5 days. We assessed clinically and electrophysiologically the effectiveness of the treatment at 5 weeks after the initial infusion. For patients in Group I and II who had not improved (or worsened) with the first treatment, we gave a one-step larger dose in the second treatment (i.e. 200 mg/kg/day x 5 days for those who had been given 50 mg/kg/day x 5 days, 400 mg/kg/day x 5 days for those who had been given 200 mg/kg/day x 5 days) after more than 9 weeks. We found that 15% of the patients in Group I, 21% in Group II and 60% in Group III improved dose-dependently with the first intravenous immunoglobulin treatment. Seven (47%) of 16 patients in Group I and 4 (40%) of 11 patients in Group II improved after the second treatment with larger doses. Adverse reactions including chill sensation, fever, skin eruption and increase in blood GOT and GPT levels were transient and mild. One patient in Group III developed left hemiparesis showing the small infarction in the right thalamus during the course of the treatment, but the symptom was mild. In conclusion, the high-dose intravenous immunoglobulin therapy (400 mg/kg/day x 5 days) is useful for treating patients with CIDP and MMN, although care must be taken of the risk of causing cerebral infarctions.     

Successful use of intravenous immunoglobulin as initial monotherapy in Landau-Kleffner syndrome

PURPOSE: There is a need for new and more effective therapies for Landau-Kleffner syndrome. In this article we present the first case in which a patient with Landau-Kleffner syndrome was given intravenous immunoglobulin (IVIG) as his first and only therapy and responded to it. METHODS: This previously healthy, left-handed boy presented at 31 months of age with a 3-month history of auditory agnosia, behavioral abnormalities, and progressive, eventually complete loss of speech. Electroencephalography (EEG) showed frequent and, in sleep, continuous right central and temporal spike slow wave discharges. Metabolic workup, magnetic resonance imaging, and auditory evoked potentials were normal. Cerebrospinal fluid IgG index was high (18%). The patient was treated with IVIG, as his initial and only therapy, receiving 500 mg/kg/day over four consecutive days. RESULTS: On the third day of IVIG, the patient started using single words, and on the fourth, two-word sentences. Two weeks later his speech and behavior returned to normal. At the end of 4 days of IVIG therapy, EEG was within normal limits. Two months later, however, he had a severe relapse clinically and by EEG. He promptly responded to another course of IVIG. A subsequent cerebrospinal fluid IgG index showed normalization (6%). Three months later he had essentially normal speech and behavior. CONCLUSIONS: Repeated, immediate, and remarkable clinical and EEG responses of this patient suggest that IVIG was helpful as first-line therapy in the treatment of Landau-Kleffner syndrome. It also supports the hypothesis that immunological mechanisms contributed to his symptoms.     

Kinetics of CSF phenytoin in children

The efficacy of intravenous phenytoin for the treatment of status epilepticus is related to the rapid entry of phenytoin into brain parenchyma. There is no information concerning the correlation between phenytoin serum and CSF concentrations in children, and the application of CSF data to clinical use. We report 7 children (2-11 yrs) who were treated or exposed to phenytoin in doses between 10.5-230 mg/kg. Lumbar puncture was performed 9 times in 6 of the patients. In one patient, an intraventricular catheter permitted successive assessment of CSF phenytoin concentrations. The ratio of CSF/serum phenytoin concentrations was 0.16 +/- 0.08, with gradual increase over the first 8 hours as the serum phenytoin concentration decreased. There was good correlation between therapeutic outcome and CSF phenytoin levels higher than 2 mcg/ml. In one patient the coma state secondary to phenytoin intoxication was associated with high CSF concentration (6 mcg/ml).     

Case of prolonged recovery from serotonin syndrome caused by paroxetine]

We report a case of serotonin syndrome in a patient being treated with paroxetine for depression. Despite prompt discontinuation of medication, his serotonin syndrome continued for 10 days before full consciousness was restored. The patient was a 48-year-old male with chief complaints of hypobulia and suicidal thoughts. He consulted as a psychiatric outpatient, and oral paroxetine 20 mg/day, etizolam 1.0 mg/day, and brotizolam 0.25 mg/day were immediately started. Upsurge of feeling and disinhibition state were noted the following day, then on treatment day 6 his condition deteriorated to substupor state and he was admitted for further treatment. On admission, change of mental condition (consciousness disturbance), perspiration, hyperreflexia, myoclonus and tremor were seen, and serotonin syndrome caused by paroxetine was suspected. Paroxetine was thus discontinued, and under intravenous drip his condition gradually improved. However, it was not until the 10th hospital day that he became fully alert. In examinations, no infectious, metabolic or organic diseases were detected. The patient's condition often improves with in 24 hours of discontinuation of the causative medication in serotonin syndrome. Symptoms continued for 10 days in this patient, however, perhaps because paroxetine was administered for 6 days before discontinuation. In addition, interaction with other medications may have occurred. Therefore, when serotonin syndrome is suspected, prompt discontinuation of the suspected causative medication, followed by close monitoring of the pharmacokinetics is warranted.     

Enoxaparin monotherapy without oral anticoagulation to treat acute symptomatic pulmonary embolism

Conventional anticoagulation for symptomatic pulmonary embolism consists of continuous intravenous unfractionated heparin as a "bridge" to oral anticoagulation. This strategy requires 5 days or more of intravenous heparin while oral vitamin K antagonists gradually achieve a therapeutic effect. Oral vitamin K antagonists require frequent blood testing to optimize dosing, and their interactions with other medications and foods make regulation difficult. Therefore we tested a different approach to therapy: long-term enoxaparin monotherapy. We randomized 60 symptomatic pulmonary embolism patients in a 2:1 ratio to 90 days of enoxaparin as monotherapy without warfarin (N=40) or to intravenous unfractionated heparin as a "bridge" to warfarin, target INR 2.0-3.0 (N=20). Enoxaparin patients received 1 mg/kg twice daily for 14 days during the acute phase followed by randomized assignment during the chronic phase to 1.0 mg/kg vs. 1.5 mg/kg once daily. In an intention-to-treat analysis, 3 of the 40 enoxaparin patients developed recurrent venous thromboembolism compared with 0 of 20 standard therapy patients (p = 0.54). One of the 40 enoxaparin patients had a major hemorrhagic complication compared with 2 of the 20 standard therapy patients (p = 0.26). Median hospital length of stay was shorter with enoxaparin compared to standard therapy (4 vs. 6 days) (p = 0.001). Following our study we can conclude that extended 3-month treatment with enoxaparin as monotherapy for symptomatic, acute pulmonary embolism is feasible and warrants further study in a large clinical trial.     

Five cases of new onset refractory status epilepticus (NORSE) syndrome: Outcomes with early immunotherapy

Cryptogenic new onset refractory status epilepticus (NORSE) syndrome has been described in both adults and children, and is often associated with poor outcome. A variety of terms have been used in the literature to refer to this syndrome. The condition may be triggered by as yet unidentified infections or an immunological mechanism. We present a series of 5 patients with NORSE syndrome treated at 2 neuroscience centres in the North of England, in whom early use of immunotherapy appears to be associated with good neurological outcomes.MethodsCase note review of the index case and four other patients was undertaken to obtain details of clinical presentation, imaging and CSF findings, infectious/inflammatory tests, management of seizures, immunotherapy and outcome.ResultsCase 1 was a 26 year old male with a prodrome of headache and vomiting. He developed refractory multifocal and generalised seizures, which required admission to intensive care unit and administration of general anaesthetic. Seizures recurred on withdrawal of barbiturate anaesthetic until day 29. MR imaging, CSF examination and serological tests for viral and autoimmune aetiologies were normal apart from positive anti-TPO antibodies: the patient had previously treated hyperthyroidism. He was initially treated with aciclovir and antibacterials. IV steroids were administered day 12 and IV immunoglobulin day 18. He made a good recovery being discharged home 2 months after admission. Seizures recurred on withdrawal of steroid therapy, and required longer term immunosuppressant treatment with azathioprine. Clinical features and investigations of the four other patients were similar. Two were given early immunotherapy with steroids and intravenous immunoglobulins and survived with few deficits. One patient who was not given immunotherapy died from complications associated with prolonged ICU stay. Outcome was not known for the fourth patient as she was repatriated to her home country in thiopentone coma.ConclusionIn our experience, early immunotherapy has been associated with good outcomes in NORSE. Multicentre collaboration is required to establish the diagnostic criteria and appropriate management of patients presenting with NORSE.     

The effect of prophylactic therapy with valproate sodium and phenobarbital in two patients with cyclic vomiting syndrome

Cyclic vomiting syndrome (CVS) is a disorder characterized by recurrent, stereotypic episodes of incapacitating nausea, vomiting, and other symptoms, separated by intervals of comparative wellness. Associated symptoms include nausea, abdominal pain, headache, and motion sickness. Recently, CVS was categorized as a migraine. Case 1 was a girl aged 4 years and 11 months, who had frequent and severe episodes of vomiting since she was 3 years old. The diagnosis of CVS was established on the basis of clinical symptoms and laboratory data. Her electroencephalogram was normal. Prophylactic therapy using a single drug such as amitriptyline, carbamazepine, phenytoin, cyproheptadine, valproate sodium or phenobarbital was not effective. However, her recurring vomiting disappeared with prophylactic therapy using valproate sodium and phenobarbital. Case 2 was a boy aged 10 years and 7 months, who had frequent episodes of vomiting since he was 1 year and 10 months old. He had been receiving intravenous hyperalimentation therapy at home since infancy because of frequent vomiting and failure to thrive. His electroencephalogram showed no abnormality. Prophylactic therapy using a single drug such as diazepam, phenytoin, valproate sodium or phenobarbital was not effective. However, his recurring vomiting disappeared with prophylactic therapy using valproate sodium and phenobarbital. There were no adverse effects in both patients. The combination therapy with valproate sodium (20 - 26 mg/kg/day) and phenobarbital (4 - 5 mg/kg/day) was effective as a prophylactic therapy in these two patients. The combination therapy with valproate sodium and phanobarbital for prophylaxis of vomiting may be helpful in patients with intractable CVS.     

Dramatic effects of high-dose intravenous gammaglobulin in each patient with intractable dermatomyositis and polymyositis

A high-dose intravenous gamma-globulin (IVGG) therapy was given to two children; one with intractable dermatomyositis (case 1) and the other with polymyositis (case 2). Case 1, a 3-year-6-month-old girl, only poorly responded to the standard oral prednisolone therapy and a pulse therapy with high-dose methyl-prednisolone. This patient showed a complete remission after a course IVGG therapy, 100 mg/kg/day iv. for 5 days, which has been maintained for 6 months up to the present. Case 2, a 13-year-6-month-old girl, also showed little improvement after the oral prednisolone therapy, and transient improvement during plasma exchange therapy. This patient showed fairly good response after three repeated courses of IVGG therapy, but not complete remission.     

Treatment of infantile spasms with zonisamide.

We determined the efficacy of and tolerability to zonisamide (ZNS) in newly diagnosed patients with infantile spasms. ZNS, 4-20 mg/kg per day, was introduced as an add-on therapy or monotherapy in 27 children with infantile spasms (cryptogenic, 2; symptomatic, 25). The dosage was initially 2-4 mg/kg per day, and then was increased by 2-5 mg/kg every 2-4 days until the seizures disappeared. Nine (33.3%) out of the 27 patients who were administered ZNS exhibited the disappearance of seizures. ZNS was effective in all the cryptogenic cases and seven (28.0%) of the symptomatic cases. The effective daily doses were 5-12.5 mg/kg (mean, 7.8 mg/kg), and the daily dosages were 40-100 mg (mean, 61.1 mg). The steady-state plasma ZNS concentrations were almost within the therapeutic range. The mean time interval between the start of ZNS therapy and the seizure disappearance was 5.0 days. Six (75.0%) of eight effective cases, the exception being one for whom EEG was not performed after the therapy, showed the disappearance of hypsarrhythmia. The recurrence of seizures were observed in four of the nine cases. No adverse reaction to ZNS was noted in any patient. In conclusion, ZNS treatment is considered to be worthwhile trying, for early stage therapy for infantile spasms.     

Low-dose therapy with carbamazepine for convulsions associated with mild gastroenteritis

We investigated the effect of carbamazepine on convulsions associated with mild gastroenteritis. Sixteen infants and young children (aged 9 months to 3 years) who experienced repetitive convulsions associated with mild gastroenteritis were admitted to our hospital. We treated the sixteen affected patients with 5 mg/kg of carbamazepine once per day until the diarrhea had stopped. Thirteen of the sixteen patients were subjected to intravenous and/or suppository administration of diazepam (0.3-0.5 mg/kg/time), and one patient suppository administration of 0.5 mg/kg diazepam and 5.7 mg/kg phenobarbital before the administration of carbamazepine. In all patients who were given diazepam and/or phenobarbital, the convulsions recurred after the administration of these medicines. The convulsions occurred 2 to 8 times (mean, 4.1 times) before the administration of carbamazepine. Fifteen of the sixteen patients had no seizures after the administration of carbamazepine. One patient had one convulsion 15 min after the administration of carbamazepine. All patients were treated with 5 mg/kg of carbamazepine once per day until the diarrhea had stopped, i.e. for 2 to 9 days (mean, 6.4 days). Low dose therapy with carbamazepine once per day is thus effective for convulsions associated with mild gastroenteritis.