Fungal infections of the central nervous system: The clinical syndromes.

Fungal infections of the central nervous system (CNS) are being increasingly diagnosed both in immunocompromised and immunocompetent individuals. Sinocranial aspergillosis is more frequently described from countries with temperate climates, more often in otherwise immunocompetent individuals. The clinical syndromes with which fungal infections of the CNS can present are protean and can involve most part of the neuroaxis. Certain clinical syndromes are specific for certain fungal infections. The rhinocerebral form is the most common presenting syndrome with zygomycosis and skull-base syndromes are often the presenting clinical syndromes in patients with sinocranial aspergillosis. Subacute and chronic meningitis in patients with HIV infection is more likely to be due to cryptococcal infection. Early recognition of the clinical syndromes in an appropriate clinical setting is the first step towards achieving total cure in some of these infections.

Economic evaluation of seizures associated with solitary cysticercus granuloma.

BACKGROUND: Patients with solitary cysticercus granuloma (SCG) develop acute symptomatic seizures because of the inflammatory response of the brain and the seizures are self-limiting. Thus seizure disorder associated with SCG provides a good model to study the total cost of illness (COI). MATERIALS AND METHODS: COI of new-onset seizures associated with SCG was studied in 59 consecutive patients registered at the epilepsy clinic. Direct treatment-related costs and indirect costs, man-days lost and wages lost were evaluated. The relative cost was calculated as the percentage of per capita gross national product (GNP) at current prices for the year 1997-1998. RESULTS: The total COI, for treating seizure disorder associated with SCG per the period of CT resolution of the lesion per patient was INR 7273.7 (US$ 174.66, I$ 943.16) and he/she would be spending 50.9% of per capita GNP The direct cost per patient was INR 5916 (US$ 137.14, 41.4% of per capita GNP). If the patient had received only AEDs for the period of resolution of CT lesion, the cost would be INR 5702.48 (US$132.2, 40% of per capita GNP). The extra expenditure on albendazole and steroid was INR 213.72 (US$ 4.95), 3.6% of the total direct cost and 20.7% of the medication cost. Indirect cost (average wage loss) per patient was INR 1312.7 (US$ 30.42) and it accounted for 9% of per capita GNP. The one-time expenditure at present costs (adjusted for inflation) to the nation to treat all the prevalence cases is to the tune of INR 1.184 billion (US$ 2.605) and 0.0037% of GNP. CONCLUSIONS: This study suggests that seizure disorder associated with SCG, a potentially preventable disorder, is a good model to study the total COI. The one-time expenditure at present costs to the nation to treat all the prevalence cases of seizure disorder associated with SCG is to the tune of INR 1.184 billion (US$ 2.605 million) and 0.0037% of GNP.

Refractory status epilepticus.

Refractory status epilepticus (RSE) is a common problem in intensive care units and emergency departments. The important risk factor predisposing patients with SE to RSE is delay in receiving treatment. Self-sustaining SE is associated with progressive, time-dependent development of pharmacoresistance. Early termination of convulsive SE by aggressive treatment is the best way to prevent RSE. RSE once develop, requires more aggressive treatment as it is associated with higher mortality and morbidity. To date, no randomized controlled trials have been done for RSE. The most experience exists with coma inducing agents like pentobarbital, midazolam and propofol. New evidence suggests for the possible role of newer AEDs.

Valproate-induced hyperammonemic encephalopathy with normal liver function.

Hyperammonemic encephalopathy with normal liver function is an uncommon serious adverse effect of valproate therapy. We retrospectively analyzed the case records of 5 patients of epilepsy on valproate with hyperammonemic encephalopathy. Of the 5 patients, 3 were on monotherapy. The mean valproate dose was 1250 mg/day and the duration of therapy ranged between 4 and 90 days. Alteration in the sensorium was the presenting clinical feature. The risk factors included high initial dose (2), long-term valproate therapy (1), and long-term valproate therapy with concomitant topiramate (1). There was good correlation between the fall in serum ammonia levels and clinical improvement. Hyperammonemic encephalopathy should be suspected in patients on valproate with altered sensorium. Response to treatment is rewarding.

Myasthenic crisis: clinical features, complications and mortality.

BACKGROUND AND OBJECTIVE: Myasthenic crisis is a life-threatening complication of myasthenia gravis (MG) and when treated aggressively is associated with good outcome. MATERIALS AND METHODS: Retrospective study of case records of patients with episodes of myasthenic crisis. RESULTS: Twenty-one (22%) of the 95 patients with MG (9 with thymoma), experienced 23 episodes of myasthenic crisis, 3 (33%) in patients with thymoma. The crisis episodes occurred within 2 years of disease onset in 11 (52%) patients. Infection was the most common primary precipitant of the crisis occurring in 65%. The median duration of the crisis episode was 11 days (7-39 days), and the median neurological intensive care unit stay was 15 days (range 9-47 days). Fifteen (65%) episodes were treated with small volume plasma exchange (PE) and 8 (35%) episodes received intravenous immunoglobulin (IVIg). The time taken for disease stabilization, the median number of days for extubation, was 8 days (range 7-12) in the PE group and 10 days (range 7-39) in the IVIg group. Disease stabilization could not be achieved in one patient in the IVIg group. Ventilator-associated pneumonia (VAP) was the commonest complication, seen in 30%. Two (8%) of the 23 episodes of crisis were fatal, one resulting from VAP and septicemia, and the other due to crisis itself. All the 19 patients who survived to discharge had complete resolution of admission symptoms. CONCLUSIONS: In patients with myasthenic crisis, both therapeutic options, PE and IVIg, are equally effective in disease stabilization. To achieve good outcomes all efforts should be directed at decreasing the duration of intubation and also aggressively treating the associated medical complications.

Continuous EEG monitoring in the evaluation of non-convulsive seizures and status epilepticus.

Non-convulsive seizures (NCSzs) and non-convulsive status epilepticus (NCSE) occur in a substantial proportion of patients with acute brain injury. These acute seizure disorders are often unrecognized and under-diagnosed. Seizure semiology of NCSz is too subtle clinically to be noticed. Most often, mental status impairment is the presenting feature. Changes in the functions of the thalamo-cortical system in patients with impaired consciousness can be detected by continuous EEG (cEEG) monitoring. cEEG monitoring allows detection of the changes at a reversible stage, often when there are no clinical indications of such phenomena. In addition EEG provides reasonable spatial resolution and excellent temporal resolution. This makes cEEG an excellent method for supplementing single or serial recordings in the detection of NCSzs and NCSE. Recent advances in digital EEG have made cEEG monitoring in the neurological intensive care unit (NICU) technically feasible. Current evidence suggests that the common clinical denominator associated with electrographic seizures or NCSzs is mental status impairment. In NCSE, the duration of ictal activity and the time of delay to diagnosis are independent predictors of poor outcome. It will be prudent to do cEEG monitoring in any patient with impaired consciousness either in the setting of acute brain injury or with no clear explanation to detect NCSzs/NCSE. Early recognition and timely intervention is likely to be associated with good outcomes.

Brain abscess due to Entamoeba histolytica.

A patient of cerebral amoebiasis due to Entamoeba histolytica with no evidence of disease elsewhere is described. He made a complete recovery after surgical excision of the abscess along with metronidazole therapy.

Clinicopathological study of thymomas--correlation of histologic subtype to myasthenia gravis and prognosis.

Thymoma is the most common primary tumor of anterior superior mediastinum. Sixty cases of thymomas over a 12 year period were analysed and the histologic subtype, according to Marino and Muller-Hermilink, classification was correlated with presence or absence of myasthenia gravis (MG) and capsular invasion. Thirty four patients had myasthenia gravis associated with thymoma and there was one case of pure red cell aplasia. There were 3 (1) predominantly cortical, 28 (20) cortical, 12 (9) mixed, 16 (4) medullary thymomas and 1 (0) thymic carcinoma (Figures in parenthesis indicate number of cases associated with MG). Capsular invasion was seen in 25 cases. Association with myasthenia gravis and capsular invasion were seen predominantly in cortical and mixed thymomas which were also associated with aggressive behaviour.

Acute disseminated encephalomyelitis.

Acute disseminated encephalomyelitis (ADEM) is an uncommon inflammatory demyelinating disease of the central nervous system. The true incidence of the disease in India is undetermined and is likely to be more frequent than reported, as the common antecedent events, exanthematous fevers and Semple antirabies vaccination, which predispose to ADEM, are still prevalent. The existing evidence suggests that ADEM results from a transient autoimmune response towards myelin or other self-antigens, possibly via molecular mimicry, or by non-specific activation of auto-reactive T cell clones. ADEM is a monophasic illness with favourable long-term outcome. Involvement of neuroaxis is variable and can be diffuse or multifocal and site restricted. Magnetic resonance imaging (MRI) is highly sensitive in detecting white matter lesions and the lesions described are rather extensive and subcortical in location. Involvement of the deep gray matter, particularly basal ganglia, is more frequent. Oligoclonal bands in CSF are usually absent. No therapy has been established by controlled trials in ADEM. Use of high-dose methylprednisolone, plasma exchange, and IVIG are based on the analogy of the pathogenesis of ADEM with that of multiple sclerosis (MS). Differentiation of ADEM from the first attack of MS is important from prognostic as well as therapeutic point of view. However, in the absence of biological marker, at times differentiation of ADEM from the initial presentation of MS may not be possible even by combination of clinical, CSF analysis, and MRI. This differentiation is more relevant to India where the incidence of MS is low.

Surface mapping of spike potential fields: visual vs. quantitative EEG analysis.

Interictal EEG spike field potentials by visual and quantitative EEG analysis were studied in 17 patients with intractable localization related epilepsy. Quantitative EEG analysis was done using commercially available window based computer program (Focus) that displayed digitally acquired EEG data and performed spline mapping. Routine EEG localized 20 spikes. Fourteen spikes had excellent congruence between manual and computer generated mapping, 6 had good congruence, and 1 had fair congruence. This study clearly proves the usefulness of spline interpolation mapping technique in localizing and characterizing the epileptiform focus.

Primary cutaneous nocardiosis with epidural abscess caused by Nocardia brasiliensis: a case report.

Dissemination of primary cutaneous nocardiosis is a rare event. An interesting case of a 20 year old female labourer with progressive weakness in both the lower limbs and large multiple subcutaneous abscesses over the back, since 4 years, is presented. MRI showed an epidural abscess compressing the cord. Histopathology of skin lesions suggested a chronic suppurative lesion. Microbiological tests on the aspirate from the skin lesion identified the causative organism as Nocardia brasiliensis.

Severity-of-illness scoring systems and models: neurological and neurosurgical intensive care units.

Predicting the outcome of critically ill patients admitted to intensive care units (ICU) has undergone considerable evolution over the last two decades. Various general purpose severity-of-illness scoring systems, Acute Physiology and Chronic Health Evaluation score (APACHE II, APACHE III), Mortality Predicting Model (MPM II), and Simplified Acute Physiology Score (SAPS II), have been extensively validated for large groups of critical care patients with mixed diagnoses and found to correlate well with observed outcome in general. The general hypothesis underlying the use of severity-of-illness scoring systems is that clinical variables that can be assessed on ICU admission and subsequent days of stay in the ICU predict survival and other outcomes of critically ill patients. Variables included in severity-of-illness scoring systems measure specific clinical and physiological functions that are major determinants of mortality. These scoring systems may be used alone within a single disease category or any other independently defined patient group to perform relative risk stratification. Variation in death rates by disease reflects the nature of the underlying process. There is a need for using these scoring systems in specialized ICUs like neurological and neurosurgical ICU as they allow, in addition to predicting outcome, evaluation of new therapies, monitoring of resource utilization and quality assessment of intensive care units.

Neurological intensive care in India--disease spectrum and outcome.

In recent years neurological and neurosurgical intensive care (NNICU) has evolved into a well-recognized subspeciality world over. However it is still a novel concept in the developing world. The admission criteria are variable and flexible. The pattern of disease in the NNICU varies according to the admission policy. In the west, cerebrovascular diseases account for a significant proportion of admissions. In a few studies from the developing countries infections of central nervous system are additional causes requiring intensive care. At our center the disease admission pattern was similar to the pattern reported from the developed countries. Predictors of outcome of neurointensive care have not been systematically evaluated. Limited available data concerns patients of neurotrauma. In addition to the disease severity indices, pre-existing chronic illness, adverse events during ICU stay, and the 24-hour presence of a physician also influence patient outcome in the NNICU.

Sleep apnoea syndromes : clinical and polysomnographic study.

Sleep apnoea syndromes have been known since long, and frequently the presenting symptoms are neurological in nature. However, these disorders have not been systematically studied and reported in the Indian literature. Out of 12,000 neurology outpatients seen by authors in 2 years, 60 had primary sleep disturbances. All these 60 patients underwent clinical evaluation and video EEG polysomnography. In 8 out of 60 (13%) patients, sleep apnoea was documented. Five patients had obstructive sleep apnoea, 3 had mixed sleep apnoea and none had pure central sleep apnoea syndrome. Three-fourths of the patients were obese (mean weight 82kg) middle aged males (mean age 46.3 years). The main symptoms encountered were excessive daytime somnolence and snoring. The symptom severity was found to correspond directly with the duration of symptoms as well as obesity. Sleep apnoea syndromes must be seriously considered and documented in all patients complaining of excessive daytime somnolence.

Clinical, pathological and magnetic resonance imaging features of focal myositis: report of three cases.

Focal myositis is a rare idiopathic form of inflammatory myositis involving a single muscle. The presentation is often as a soft tissue pseudotumour. Magnetic resonance imaging (MRI) is a useful noninvasive imaging modality to demonstrate focal nature of the lesion. We describe three patients presenting as pseudotumour of the lower leg. MRI showed hyperintense signals in the involved muscle.