Spinocerebellar syndrome in patients infected with human T-lymphotropic virus types I and II (HTLV-I/HTLV-II): report of 3 cases from Panama.

Cerebellar symptoms at onset are unusual in HTLV-I/II-associated tropical spastic paraparesis (TSP). A prospective study of neurological disorders in Panama (1985-1990) revealed 13 patients with TSP and 3 with HTLV-I/II-associated spinocerebellar syndrome (HSCS) presenting at onset loss of balance, wide-based stance and gait, truncal instability, and mild leg ataxia (vermian cerebellar syndrome), with absent upper limb dysmetria but with postural tremor, downbeat nystagmus, and dysarthria. In 4-5 years, spinal cord manifestations of TSP developed, including spastic paraparesis, pyramidal signs, bladder and sphincter disturbances. Two patients were infected with HTLV-I and another one, a Guaymi Amerindian woman, with HTLV-II. Magnetic resonance imaging (MRI) demonstrated cerebellar atrophy involving predominantly the superior vermis. Mild axonal peripheral neuropathy in the lower limbs, dorsal column involvement and inflammatory myopathy were found by neurophysiology studies. There are 14 similar cases reported in Japan and Canada, but to our knowledge these are the first documented cases of HSCS in the tropics. A cerebellar syndrome constitutes another form of presentation of HTLV-I/II infection of the nervous system.

Gene-environment interactions in the Italy-Argentina "Colombo 2000" project.

The phenomenon of massive migration is a true "natural experiment" that offers opportunities for the study of gene-environment interactions in disease pathogenesis. Comparison of disease incidence, prevalence and mortality in the original population and in the migrant group, exposed to vastly different environmental influences, may reveal the presence of either risk factors or protective influences in one of the groups. As part of the "Colombo 2000" project to study the large Italian migration to Argentina, differences in mortality for neurological diseases have been found. Higher mortality rates for brain tumors, psychiatric diseases, Parkinson's disease, Alzheimer's disease, and motor neuron diseases were found in Italy while Argentina had mortality rates five times higher than Italy for alcohol-related deaths and two times higher for hemorrhagic strokes. Further study of these areas of difference is suggested using case-control, genetic, and cross-sectional studies in Italy and Argentina.

Epidemic neuropathy in Cuba: a public health problem related to the Cuban Democracy Act of the United States.

In 1992, the USA embargo on Cuba was tightened through the passage of the Cuban Democracy Act (CDA) that explicitly restricts food and medical supplies. The embargo has contributed to cause a number of public health problems in Cuba including: (1) an epidemic of more than 50,000 cases of optic and peripheral neuropathies in 1992-1993, resulting from dietary deficiency; (2) an epidemic of esophageal stenoses in toddlers who inadvertently drank liquid lye as a result of a soap shortage for which liquid lye was substituted; (3) an outbreak of Guillain-Barré syndrome in Havana, in June and July 1994, resulting from water contamination due to lack of chemicals for water treatment to eliminate Campylobacter sp.; (4) outbreaks of self-inflicted disease and injuries caused by rioting among Cubans detained at the US Naval base at Guantánamo Bay, and (5) a decline in medical practice standards and public health indicators in Cuba resulting from the enactment of the CDA, documented by the American Public Health Association in 1993 and confirmed in March 1997 by the American Association for World Health. Despite this evidence, the Cuban embargo remains a politically sensitive subject in the USA, resistant to public health concerns, as evidenced by the recent passage of the Helms-Burton Act. The public health effects of the CDA need to be reviewed with possible revocation or at least modification.

Ventana fleuropericardica por videotoracospia. Experiencia preliminar de tres casos / Fleuroperdicardial window for video thoracoscopy: prelimirary experience with three cases

Presenta este trabajo el resultado de tres ventanas pericárdicas realizadas por videotoracoscopía en la Primera Catedra de Clínica Quirúrgica entre marzo y setiembre de 1997. La edad ociló entre 18 y 60 años un varon y dos mujeres. Estas ultimas consultaron por derrame paraneoplásico posterior a cirugias por neoplasias de endometrio y cervix. El varon por ortopnea con antecedente de herida con arma blanca a niveldel precordio. Los tres fueron sometidosvideotoracoscopia izquierda colocando tres trócarescomo canales de trabajo, previa identificacióo y preservación delnervvio frenico se realizaron las ventanas entre 4 y6 cms.de diámetro. Los derrames fueronserohemáticos y el volumen ociló entre 900 y 200 ml,mejorando ostenciblemente la funcionalidad cardiaca.El tiempo operatorio promedio fue de 30 minutos Pensamos que la técnica es sencilla y permite la realización del procedimiento vajo visión directa

On politics and health: an epidemic of neurologic disease in Cuba.

Political decisions may cause disease. During 1992 and 1993, an epidemic of neuropathy in Cuba--largely overlooked by U.S. physicians--affected more than 50,000 persons and caused optic neuropathy, deafness, myelopathy, and sensory neuropathy. Patients with the neurologic disease responded to B group vitamins, and oral vitamin supplementation of the population curbed the epidemic. Dietary restrictions and excessive carbohydrate intake were the immediated cause of the epidemic; however, the primary cause might have been political. Political changes in eastern Europe had major repercussions on Cuba's economy and food supply. In turn, these changes compounded the effects of internal political decisions in the island, leading toward isolationism and economic dependence on the former Soviet Union. Also, for more than 30 years, the United States has maintained an economic embargo against Cuba. In 1992, the U.S. embargo was tightened by the Torricelli amendment (or the Cuba Democracy Act), which prohibited third-country subsidiaries of U.S. companies from trading with Cuba and prevented food and medicines from reaching the island; this amendment produced a virtual economic blockade. Penuries resulting from all these political events resulted in the largest epidemic of neurologic disease in this century. Physicians may need to use their influence to modify political decisions when these decisions result in adverse health consequences. The American Academy of Neurology has issued a plea to encourage physicians and other health personnel to support efforts leading to lifting of the U.S. embargo against Cuba for humanitarian reasons.

Childhood Guillain-Barré syndrome in Paraguay, 1990 to 1991.

During 1990 to 1991, through a national surveillance program for poliomyelitis, the Paraguayan Ministry of Health received reports of 50 children with incident acute flaccid paralysis (< 15 years old). On the basis of established criteria, 37 were diagnosed with Guillain-Barré syndrome. The average annual incidence rate for 1990 to 1991 was 1.1/100,000 children. The clinical course was more benign than reported in other pediatric series. There were low rates of hospitalization (57%), respiratory compromise (8%), and intubation (5%). The overall severity, however, was similar to that described in previous reports, with a 3% case-fatality rate and an 81% total recovery rate at 12 months. Seventy-six percent of patients had symptom onset during January to April, the warmest months of the year. Thirty percent of patients had definite or possible exposure to organophosphate pesticides, and the peak use coincides with the peak incidence of Guillain-Barré syndrome. There was no correlation between occurrence of Guillain-Barré syndrome and prior immunization.

An epidemic in Cuba of optic neuropathy, sensorineural deafness, peripheral sensory neuropathy and dorsolateral myeloneuropathy.

An epidemic outbreak of peripheral neuropathy affected Cuba in 1992-93 resulting in 50,862 cases (national cumulative incidence rate (CIR) 461.4 per 100,000). Clinical forms included retrobulbar optic neuropathy, sensory and dysautonomic peripheral neuropathy, dorsolateral myeloneuropathy, sensorineural deafness, dysphonia and dysphagia, spastic paraparesis, and mixed forms. For epidemiological purposes, cases were classified as optic forms (CIR 242.39) or peripheral forms (CIR 219.25). Increased risk was found among smokers (odds ratio (OR) 4.9), those with history of missing meals (OR 4.7) resulting in lower intake of animal protein, fat, and foods that contain B-vitamins, combined drinking and smoking (OR 3.5), weight loss (OR 2.8), excessive sugar consumption (OR 2.7) and heavy drinking (OR 2.3). Optic neuropathy was characterized by decreased vision, bilateral and symmetric central or cecocentral scotomata, and loss of color vision due to selective lesion of the maculopapillary bundles. Peripheral neuropathy was a distal axonopathy lesion affecting predominantly large myelinated axons. Deafness produced selective high frequency (4-8 kHz) hearing loss. Myelopathy lesions combined dorsal column deficits and pyramidal involvement of lower limbs with spastic bladder. Clinical features were those of Strachan syndrome and beriberi. Intensive search for neurotoxic agents, in particular organophosphorus esters, chronic cyanide, and trichloroethylene intoxication, yielded negative results. Treatment of patients with B-group vitamins and folate produced rewarding results. Most patients improved significantly and less than 0.1% of them remained with sequelae; there were no fatal cases. Supplementation of multivitamins to the entire Cuban population resulted in curbing of the epidemic. Overt malnutrition was not present, but a deficit of micronutrients, in particular thiamine, cobalamine, folate and sulfur amino acids appears to have been a primary determinant of this epidemic.

Epidemic neuropathy in Cuba: morphological characterization of peripheral nerve lesions in sural nerve biopsies.

More than 50,000 patients were affected in Cuba during an epidemic outbreak of peripheral neuropathy from January 1992 until September 1993. The disease presented as either a retrobulbar optic neuropathy, a predominantly sensory peripheral neuropathy, a dorsolateral myeloneuropathy, or as mixed forms. The morphological findings in sural nerve biopsies from 34 patients with various forms of the disease are presented here. Frozen, paraffin and semi-thin sections were prepared for light and electron microscopy, immunohistochemistry and morphometric analysis. Every case presented morphological alterations ranging from mild axonal dystrophy (9 cases, or 27%) to moderate and severe axonal damage (25 cases, or 73%). In 6 cases (18%), axonal damage was accompanied by perineural fibrosis and vascular abnormalities. Axonal regeneration was noted in 8 cases (23%) and remyelination in 9 (26%). Morphometric analysis showed a predominant loss of myelinated fibers in 92% of the patients. Quantification of myelinated fiber loss in 11 patients revealed a remarkable decrease in large caliber fibers. Scarce mononuclear cells were observed in 17 cases. No virus-like elements were seen. The morphological features found in this study indicate that, regardless of the clinical presentation, peripheral nerve lesions of the epidemic neuropathy in Cuba correspond to an axonal neuropathy. These lesions are compatible with nutritional, toxic, or metabolic etiologies. An inflammatory etiology would be unusual with these lesions.

Epidemic neuropathy in Cuba: a plea to end the United States economic embargo on a humanitarian basis.

During 1992-1993, an epidemic of neurologic disease in Cuba affected 50,862 patients with optic neuropathy, sensorineural deafness, predominantly sensory peripheral neuropathy, and dorsolateral myelopathy. The clinical syndromes were identical to those of prisoners of war subjected to nutritional restriction in tropical prison camps during World War II (Strachan's disease). A dietary deficiency of group B vitamins and sulfur-containing amino acids appears to have been the primary cause of the epidemic. This was a consequence of economic and political events in Cuba linked to the collapse of the Soviet Union and socialist countries. The recently toughened 30-year-old US economic embargo on Cuba contributed to these problems and hampered the investigation, treatment, and prevention of the epidemic. A plea is made to the neurologic community to request the lifting of the trade blockade on a humanitarian basis.

Human T-lymphotropic virus type I DNA in spinal cord of tropical spastic paraparesis with concomitant human T-lymphotropic virus type I negative Hodgkin's disease

We studied a 58 year old black women from Barbados who simultaneously developed myelopathy and lymphoma with human T-lymphotropic virus type I (HTLV-I) antibodies in serum and cerebrospinal fluid and died 3 years after onset. Neuropathological examination showed typical tropical spastic paraparesis (TSP). The polymerase chain reaction (PCR) demonstrated defective proviral genome retaining the HTLV-I pX and env regions in thoracic spinal cord, the level most severely affected. Defective HTLV-I in the nervous system retaining the pX region may be relevant to pathogenesis because circulating CD8+ cytotoxic lymphocytes specific for HTLV-I pX occur in HTLV-I myelopathy. This patient's lymph node biopsy specimen was consistent with Hodgkin's disease (HD), nodular sclerosis subtype, of B-cell origin. The PCR in the paraffin-embedded lymph node involved by HD failed to amplify HTLV-I proviral sequences. Complete HTLV-I proviral amplification was obtained in paraffin-embedded lymph node form positive controls (adults T-cells leukemia). To our knowledge the association of TSP and HD has not been reported previously. Despite claims the HD may be associated with HTLV-I, we demonstrated absence of HTLV-I infected T-cell in the lymphoid infiltrate of HD in this case, positive HTLV-I serology notwithstanding.(AU)

Skeletal muscle involvement in tropical spastic paraparesis/HTLV-1-associated myelopathy.

The frequency of muscle involvement in TSP/HAM is not known, nor is the precise role that HTLV-1 and the diverse cytokines play in the genesis of HTLV-1-associated diseases. In order to better define the frequency and characteristics of the skeletal muscle involvement in TSP/HAM, we studied 11 affected patients. EMG was performed in 9 patients and muscle biopsy was performed in all 11. Muscle tissue was analyzed using: reverse transcriptase PCR for interleukin-1 in 8; PCR for HTLV-1 proviral DNA in 5; and electron microscopy for viral particles in 3. We found pathologic alterations in all 11 patients. Four patients (36%) had a neurogenic process, while a primary muscle involvement was observed in the rest (64%). Four patients (36%) had polymyositis, and 3 (27%) had a noninflammatory myopathy. Muscle weakness in the upper limbs was significantly associated with inflammation in the muscle biopsy. EMG was abnormal in only 2 of 9 patients. Reverse transcriptase PCR did not demonstrate message for interleukin-1 in any sample examined. PCR did identify HTLV-1 proviral DNA in the muscle of 3 patients. Retroviral-like particles were found, by EM, in only one biopsy. HTLV-1 may play an important role in the pathogenesis of the frequent myopathies associated with HAM/TSP.

Therapy for neurocysticercosis: a reappraisal.

Accepted approaches to therapy for the different forms of neurocysticercosis are reviewed. Therapy must be individualized according to the level of disease activity and the location of the parasite. Patients with inactive disease should receive only symptomatic treatment. In contrast, patients with parenchymal brain cysts must receive a course of anticysticercal drugs. Both albendazole and praziquantel are useful; however, recent evidence favors the former as the drug of choice for this form of the disease. Albendazole (but not praziquantel) is also effective in the treatment of giant subarachnoid cysts; such medical treatment obviates surgery in some cases. Patients with ventricular cysts may also benefit from medical therapy; however, surgery is the current approach to this type of lesion, as it is to spinal cysticercosis. Although intraocular cysts have classically been resected by surgery, a recent study indicates that albendazole is equally effective. For patients with mixed forms of neurocysticercosis, therapeutic measures related to--but not directly targeting--the disease (i.e., steroid administration for brain edema or shunt placement for hydrocephalus) should be contemplated before therapy with anticysticercal drugs is instituted.

Neurological manifestations of malaria.

The involvement of the nervous system in malaria is reviewed in this paper. Cerebral malaria, the acute encephalopathy which complicates exclusively the infection by Plasmodium falciparum commonly affects children and adolescents in hyperendemic areas. Plugging of cerebral capillaries and venules by clumped, parasitized red cells causing sludging in the capillary circulation is one hypothesis to explain its pathogenesis. The other is a humoral hypothesis which proposes nonspecific, immune-mediated, inflammatory responses with release of vasoactive substances capable of producing endothelial damage and alterations of permeability. Cerebral malaria has a mortality rate up to 50%, and also a considerable longterm morbidity, particularly in children. Hypoglycemia, largely in patients treated with quinine, may complicate the cerebral symptomatology. Other central nervous manifestations of malaria include intracranial hemorrhage, cerebral arterial occlusion, and transient extrapyramidal and neuropsychiatric manifestations. A self-limiting, isolated cerebellar ataxia, presumably caused by immunological mechanisms, in patients recovering from falciparum malaria has been recognized in Sri Lanka. Malaria is a common cause of febrile seizures in the tropics, and it also contributes to the development of epilepsy in later life. Several reports of spinal cord and peripheral nerve involvement are also available. A transient muscle paralysis resembling periodic paralysis during febrile episodes of malaria has been described in some patients. The pathogenesis of these neurological manifestations remains unexplored, but offers excellent perspectives for research at a clinical as well as experimental level.