Brain-stem auditory evoked potentials in human immunodeficiency virus-seropositive patients with and without acquired immunodeficiency syndrome.

Brain-stem auditory evoked potentials were recorded in 35 human immunodeficiency virus (HIV)-seropositive subjects from the Centers for Disease Control groups III and IV, 24 HIV-negative drug abusers, and 62 normal healthy controls. None of the patients had evidence of neurological complications. History of alcohol consumption was an exclusion criterion. The values of central conduction times I-V and III-V showed significant differences between the HIV-seropositive subjects and normal healthy controls, as well as between the HIV-seropositive subjects and HIV-negative drug abusers. Central conduction times I-III showed no differences between groups, except in the left ear of Centers for Disease Control group IV compared with controls. No statistical differences were found in the central conduction times between HIV-negative drug abusers and normal healthy controls. The results suggest a subclinical involvement of the upper brain stem in HIV infection. It could be produced by direct action of the virus on central nervous system structures.

Reliability of the NINDS Myotatic Reflex Scale.

The assessment of deep tendon reflexes is useful for localization and diagnosis of neurologic disorders, but only a few studies have evaluated their reliability. We assessed the reliability of four neurologists, instructed in two different countries, in using the National Institute of Neurological Disorders and Stroke (NINDS) Myotatic Reflex Scale. To evaluate the role of training in using the scale, the neurologists randomly and blindly evaluated a total of 80 patients, 40 before and 40 after a training session. Inter- and intraobserver reliability were measured with kappa statistics. Our results showed substantial to near-perfect intraobserver reliability, and moderate-to-substantial interobserver reliability of the NINDS Myotatic Reflex Scale. The reproducibility was better for reflexes in the lower than in the upper extremities. Neither educational background nor the training session influenced the reliability of our results. The NINDS Myotatic Reflex Scale has sufficient reliability to be adopted as a universal scale.

Accuracy of clinical criteria for the diagnosis of progressive supranuclear palsy (Steele-Richardson-Olszewski syndrome).

We assessed the validity and interrater reliability of neurologists who, using four different sets of previously published criteria for the clinical diagnosis of progressive supranuclear palsy (PSP), also called Steele-Richardson-Olszewski syndrome, rated 105 autopsy-proven cases of PSP (n = 24), Lewy body disease (n = 29), corticobasal ganglionic degeneration (n = 10), postencephalitic parkinsonism (n = 7), multiple system atrophy (n = 16), Pick's disease (n = 7), and other parkinsonian or dementia disorders (n = 12). Cases were presented in random order to six neurologists. Information from each patient's first and last visits to the medical center supplying the case was presented sequentially to the rater, and the rater's diagnosis was compared with the neuropathologic diagnosis of each case. Interrater agreement for the diagnosis of PSP varied from substantial to near perfect, but none of the criteria had both high sensitivity and high predictive value. Because of these limitations, we used a logistic regression analysis to identify the variables from the data set that would best predict the diagnosis. This analysis identified vertical supranuclear palsy with downward gaze abnormalities and postural instability with unexplained falls as the best features for predicting the diagnosis. From the results of the regression analysis and the addition of exclusionary features, we propose optimal criteria for the clinical diagnosis of PSP.

Polymerase chain reaction used to detect candidemia in patients with candiduria.

OBJECTIVES: Candiduria has been shown to be an early marker of disseminated fungal infection in critically ill patients who have undergone surgery. The management of candidemia and disseminated candidiasis depends on rapid and definitive identification of Candida. Routine or fungus-specific blood cultures are unreliable and require a large quantity of blood for incubation. We describe the importance of the polymerase chain reaction (PCR) procedure in the early detection of candidemia in critically ill patients who develop candiduria and the favorable outcome in treating these patients with systemic antifungal therapy. METHODS: We compared the results of cultures and PCR to detect the presence of C. albicans in the blood of two critically ill patients with clinical candidiasis and candiduria. RESULTS: PCR detected the presence of C. albicans deoxyribonucleic acid (DNA) in urine and blood specimens of both patients in spite of negative blood cultures and did not detect fungal DNA after systemic antifungal therapy. CONCLUSIONS: Candiduria manifests as an early sign of candidemia, and systemic antifungal therapy timed appropriately based on the clinical condition and onset of candiduria will improve outcome. Detection of fungal DNA in blood by PCR is of value in establishing the diagnosis. Additional studies with a larger sample size are required to evaluate the specificity and sensitivity of PCR as a routine diagnostic test for candidemia.

Impaired insight in Alzheimer's disease.

We studied insight into illness in 41 patients with probable Alzheimer's disease. An impaired insight score was developed by measuring discrepancies between patient report and caregiver report on standard instruments of activities of daily living. Insight was more impaired in subjects with greater dementia severity and subjects with paranoid delusions. In a multivariate analysis, the best neuropsychological predictors of impaired insight were the Continuous Performance Test and the Visual Reproduction Test. We speculate that the impaired insight of Alzheimer's disease has two components: confabulation reflecting prefrontal dysfunction and anosognosia reflecting right-hemisphere dysfunction.

Treatment of Tourette's syndrome with calcium antagonists.

Six males and one female with chronic tic disorders, whose ages ranged from 12 to 31 years, were evaluated before treatment, after 1 month on placebo, after a single 10 mg nifedipine dose (three patients), and monthly while on flunarizine 10-15 mg (mean dose of 13 mg). None of the patients receiving nifedipine improved, but treatment with flunarizine significantly decreased both motor and phonic tic severity and frequency in all but one patient. Side effects included mild transient headaches in one patient, depression in one, and bradykinesia in two. Although a double-blind study is essential to validate our findings, results suggest that flunarizine is a useful drug in the treatment of Gilles de la Tourette syndrome.

Quantitative measurement of delta activity in Alzheimer's disease.

Quantitative measurements of delta activity were made in 10 healthy elderly controls and 31 subjects with Alzheimer's disease. Delta activity did not discriminate between the healthy elderly controls and the early mild Alzheimer's disease subjects. However, delta activity was a significantly greater percentage of total EEG power in the moderate-to-advanced Alzheimer's subjects when compared to either the healthy controls or mild Alzheimer subjects. In the T3 and T4 electrodes, delta activity in the moderate-to-advanced Alzheimer subjects was 78.3% and 47.6% higher, respectively, than in control subjects. Furthermore, delta activity was an excellent predictor of dementia severity within the 31 subjects with Alzheimer's disease.

Vascular dementias in the elderly.

In this review, challenging and controversial aspects of vascular dementias in the elderly are examined. Topical discussions underscore diagnostic criteria, epidemiology, clinical syndromes and diagnosis, prognosis and treatment. The need for a reappraisal of dementias with a shift from broad categorization to identification of specific vascular mechanisms that contribute to cognitive impairment and the need for more basic epidemiological studies are highlighted. With this information, a substantial scientifically-based approach to prevention and treatment can be undertaken.

Loss of motor units in Alzheimer's disease.

Little attention has been paid in the literature to the state of the peripheral nervous system (PNS) in Alzheimer's disease (AD). We conducted a comprehensive electrophysiological study in 15 AD patients looking for functional abnormalities within their PNSs. A reduction of the number of functioning motor units (MU) was found in the thenar and soleus muscles of most of these patients without enlargement of the remaining MUs territories, while the motor and sensory conduction velocities of the peripheral nerves were preserved. These results suggest dysfunction of the spinal motoneurones in patients afflicted with this condition.

Hereditary essential tremor in Buenos Aires (Argentina).

A descriptive trial of essential tremor in Buenos Aires city is proposed. It may be considered as the first one like this in Latin America. During a 15 year period, sixteen families with essential tremor diagnosis have been examined, making a total of 39 patients (20 males and 19 females). The disease was basically studied from its semiological, clinico-evolutive and therapeutical view point, following a protocol. Our results indicate -- a. The clinico-evolutive characteristics: its frequency (according to race, sex, social status, age of beginning and physiopathological type), morbidity and mortality, evolution, prognosis, triggering factors, longevity and multiparity. b. The different treatment given to our patients with discussion of their pharmacokinetic and pharmacodynamic basis and evaluation of the best responses. In this matter, it is concluded that both primidone (750 mg/daily) and/or propranolol (160-240 mg/daily) are undeniably the drugs of first choice for the treatment of this disease. A comparison of the clinico-therapeutic features of this tremor in Buenos Aires and other cities is done. The study of this syndrome in Buenos Aires does not give different results from those obtained in Europe and USA.

Cognitive impairment in human chronic Chagas' disease.

UNLABELLED: We proposed to investigate subclinical cognitive impairment secondary to chronic Chagas' disease (CCD). No similar study was previously done. The neuropsychological performance of 45 chronic Chagasic patients and 26 matched controls (age, education place and years of residency in endemic area) was compared using the Mini Mental State Exam (MMSE), Weschler Memory Scale (WMS) and the Weschler Adult Intelligent Scale (WAIS). Non-parametric tests and Chi2 were used to compare group means and multivariate statistics in two way frequency tables for measures of independence and association of categorical variables with the disease. RESULTS: Chagasic patients showed lower MMSE scores (p < .004), poor orientation (p < .004), and attention (p < .007). Lower WMS MQ were associated with CCD (Chi2 5.9; p < .01; Fisher test p < .02). Lower WAIS IQ were associated with CCD (Chi2 6.3, p < .01; Fisher test p < .01) being the digit symbol (p < .03), picture completion (p < .03), picture arrangement (p < .01) and object assembly (p < .03) subtests the most affected. The impairment in non-verbal reasoning, speed of information processing, problem solving, learning and sequencing observed in chronic Chagas disease patients resembles the cognitive dysfunction associated with white matter disease.

[Clinical heterogeneity of Alzheimer's disease. Different clinical profiles can predict the progression rate]. / Heterogeneidad clinica de la enfermedad de Alzheimer. Diferentes perfiles clinicos pueden predecir el intervalo de progresion.

INTRODUCTION: Alzheimer's disease (AD) is a degenerative dementia that may disclose different cognitive, behavioral, psychiatric and functional symptoms since onset. These distinct cognitive profiles support the conception of clinical heterogeneity and account for AD's highly variable rate of progression. In spite of strict diagnostic criteria NINCS ADRDA's and DSM IV the clinical certainty is only about 85%. Mayeux define 4 subtypes: a). Benign: mild cognitive and functional impairment without focal signs and late onset behavioral signs, slow progression; b). Myoclonic: usually of presenile onset with severe cognitive deterioration, mutism and early onset myoclonus; c). Extrapyramidal: early onset akineto rigid signs with severe cognitive, behavioral and psychiatric involvement; d). Typical: gradual and progressive cognitive, behavioral and functional impairment. The differentiation of these subtypes will allow us to define discrete patterns of progression, to define prognostic subgroups, and to homogenize them for clinical research and drug trials. DEVELOPMENT: We examined 1000 charts of probable AD patients from the Santojanni Center. We found 42% extrapyramidal, 35% typical, 15% benign and 8% myoclonic. The early onset of parkinsonism and myoclonus predict a rapidly evolving cognitive impairment and a more severe rate of progression with psychiatric disorders and dependency in activities of daily living. (DADL) Patients with low level of education, low cognitive performance at entry as well as those with rapid rate of cognitive deterioration had a faster rate of progression to DADL. CONCLUSION: Delusions, low level of education, extrapyramidal signs and motor hyperactivity but not hallucinations, and anosognosia were the best non cognitive predictors of DADL.

Dementia in Argentina and other Latin-American countries: An overview.

Latin-American countries are expected to experience an expansion of the elderly population, as life expectancy increases. We reviewed the literature to determine the frequency of dementia in our region and surveyed selected Latin-American countries to determine the availability of diagnostic and treatment services and long-term care facilities. Latin-American countries face a challenge to develop public health strategies to cope with the anticipated heightened number of elderly with cognitive impairment.

Presenilin 1 Met146Leu variant due to an A --> T transversion in an early-onset familial Alzheimer's disease pedigree from Argentina.

Most of the cases of early-onset familial Alzheimer's disease (FAD) are related to missense mutations in the presenilin 1 (PS-1) gene on chromosome 14. Although PS-1 mutations are distributed throughout the entire open reading frame, most mutations are found in transmembrane region II and hydrophilic loop VI encoded by exons 5 and 8, respectively. These two groups of substitutions are associated with an age of onset of 40-43 years for exon 5 and 45-55 years for exon 8, respectively. We have previously described a South American pedigree from Argentina with early-onset FAD (mean age of onset 38.9 +/- 3.9 years) with no mutations in exons 16 and 17 of the beta-protein precursor gene (betaPP770 transcript). Here we report the identification of an A --> T transversion at the first position of codon 146 of PS-1 in these patients. This missense mutation results in a Met --> Leu substitution, as reported for the Italian pedigrees Tor1.1 and FAD4. The significant differences in ages of onset and death among members of generations II-III and IV suggest that other genetic and/or environmental factors may influence disease phenotype in this pedigree.

Vascular dementia: the Latin American perspective.

Population aging is a process that is especially accelerated in some parts of the world. One example is in Latin America. As with other developing regions, Latin America has to confront population "graying" in the context of an emerging economy. As a result of this and of their health history, the prevalence and incidence of age-related pathologies are different than those in the developed world. The burden of dementia is significant for patients, families, health systems, and public health. The aim of this paper was to summarize data from the scarce dementia epidemiological studies available in Latin America, the diagnostic criteria used in most countries and the most widely used diagnostic tools and neuropsychological assessment instruments (some of them translated, validated, and harmonized). Reference is made to the approval process and availability in Argentina of dementia and cognitive decline-related drugs.

A double-blind, randomized, fixed-dose trial of fluoxetine vs. amitriptyline in the treatment of major depression complicating Alzheimer's disease.

The objective of this study was to determine the relative efficacy and safety of fluoxetine and amitriptyline in the treatment of major depression complicating Alzheimer's disease (AD). The sample included 37 patients with AD and major depression. The study design was a double-blind, fixed-dose, randomized clinical trial with 45 days of follow-up. The outcome measures were the Hamilton Depression Rating Scale (Ham-D), the Mini-Mental State Exam (MMSE), and the number of dropouts from each arm of the study. Efficacy was similar for fluoxetine and amitriptyline. At Day 45, there was a mean 9.4-point reduction in Ham-D scores (t[df,62] = 9.68, P < 0.0001) and a 2.4-point mean increase in MMSE scores as compared to baseline (t[df,2] = 2.69, P = 0.009). Eleven (58%) of the amitriptyline-treated patients dropped out, compared with 4 (22%) of the fluoxetine-treated patients (chi 2[df,2] = 8.9, P = 0.017). The authors conclude that antidepressant treatment for major depression complicating AD is effective. While fluoxetine and amitriptyline are equally effective, fluoxetine is better tolerated.