[Factors associated with the hospital at home workload: A Delphi consensus study]

OBJECTIVES

To identify and prioritize a list of factors that contribute to the workload of the hospital at home (HaH) professionals.

MATERIAL AND METHODS

A qualitative methodology study performed between January and December 2019 in the 10 HAH units of the Basque Country. The data were obtained in 4phases: 1. Systematic literature search and review; 2. Expert group meeting; 3. Consensus method: Delphi technique (2 survey rounds) and nominal group meeting; 4. Meeting of the research team.

RESULTS

In the systematic literature search and review 85 factors were initially identified. These were reduced to 38 after the 8-person expert group meeting, in which 10 new factors were added. After the 2 Delphi rounds (106 and 57 professionals, respectively), 17 factors were maintained and 12 remained in doubt. The latter were evaluated at the nominal group meeting, consisting of 13 professionals who decided to eliminate 5 factors, include 3, and keep 3 as doubt. After the 8-person research team meeting, 14 potential factors were finally selected. They are related to the place of residence, the health state and social situation of the patients, as well as the health care provided at home.

CONCLUSIONS

The identified factors could serve for improving the organization and optimize the daily word of the HaH professionals.

Immunomodulatory properties of molecules from animal venoms

The immune system can amplify or decrease the strength of its response when it is stimulated by chemical or biological substances that act as immunostimulators, immunosuppressants, or immunoadjuvants. Immunomodulation is a progressive approach to treat a diversity of pathologies with promising results, including autoimmune disorders and cancer. Animal venoms are a mixture of chemical compounds that include proteins, peptides, amines, salts, polypeptides, enzymes, among others, which produce the toxic effect. Since the discovery of captopril in the early 1980s, other components from snakes, spiders, scorpions, and marine animal venoms have been demonstrated to be useful for treating several human diseases. The valuable progress in fields such as venomics, molecular biology, biotechnology, immunology, and others has been crucial to understanding the interaction of toxins with the immune system and its application on immune pathologies. More in-depth knowledge of venoms' components and multi-disciplinary studies could facilitate their transformation into effective novel immunotherapies. This review addresses advances and research of molecules from venoms that have immunomodulatory properties.

HEALTH STATUS AND LIFESTYLE HABITS OF VULNERABLE, COMMUNITY-DWELLING OLDER PEOPLE DURING THE COVID-19 LOCKDOWN

This study evaluated the health status and lifestyle habits of vulnerable, community-dwelling older adults during the first COVID-19 lockdown in Spain. A telephone assessment was carried out in 38 individuals (71% women), with a Barthel index ≥85 who were frail or had a high risk of falls. Data were compared with those from an assessment performed 9 months earlier. In the latter part of the lockdown, a high percentage of the studied individuals showed difficulties in walking up 10 steps and reported sleep problems (66%) and pain (74%). On the other hand, participants were not anxious/depressed (71%) and the majority did not report loneliness (60%). Compared to the earlier assessment, we identified a decline in functional capacity and worsening of nutritional status, but an increase in family support. Efforts should be made to implement intervention programs seeking to avoid accelerated decline under the current pandemic situation, and especially during possible new lockdowns.

Antivenom effect on lymphatic absorption and pharmacokinetics of coral snake venom using a large animal model

Context: Historically, administration and dosing of antivenom (AV) have been guided primarily by physician judgment because of incomplete understanding of the envenomation process. As demonstrated previously, lymphatic absorption plays a major role in the availability and pharmacokinetics (PK) of coral snake venom injected subcutaneously, which suggests that absorption from subcutaneous tissue is the limiting step for venom bioavailability, supporting the notion that the bite site is an ongoing venom depot. This feature may underlie the recurrence phenomena reported in viperid envenomation that appear to result from a mismatch between venom and AV PK. The role of lymphatic absorption in neutralization of venom by AV administered intravenously remains unclear. Methods: The effect of AV on systemic bioavailability and neutralization of Micrurus fulvius venom was assessed using a central lymph-cannulated sheep model. Venom was administered by subcutaneous injection in eight sheep, four with and four without thoracic duct cannulation and drainage. Two hours after venom injection, AV was administered intravenously. Venom and AV concentrations in serum and lymph were determined by ELISA assay from samples collected over a 6-h period and in tissues harvested post-mortem. Results: After AV injection, venom levels in serum fell immediately to undetectable with a subsequent increase in concentration attributable to non-toxic venom proteins. In lymph, AV became detectable 6 min after treatment; venom levels dropped concurrently but remained detectable 4 h later. Post-mortem samples from the venom injection site confirmed the presence of venom near the point of injection. Neither venom nor AV was detected at significant concentrations in major organs or contralateral skin. Conclusions: Intravenous AV immediately neutralizes venom in the bloodstream and can extravasate to neutralize venom absorbed by lymph but this neutralization seems to be slow and incomplete. Residual venom in the inoculation site demonstrates that this site functions as a depot where it is not neutralized by AV, which allows the venom to remain active with slow delivery to the bloodstream for ongoing systemic distribution.

Availability and use of healthcare resources in prisons according to the transference model: a comparative study in Spain

OBJECTIVE

In most European countries, correctional healthcare provision is under strain or in the process of change regarding its management model and the implications that such modifications may entail for the improvement of inmates' health. This paper compares the functioning and the results of health management in a facility whose healthcare service is integrated within an autonomic health system and others which depend on the department of corrections.

MATERIALS AND METHODS

Cross-sectional study where the study unit is the facility itself. From the data collected from the record of Monthly Health Statistics of Penitentiary Institutions we have constructed a series of indicators according to the recommendations of the National Health System.

RESULTS

The physician to nurse ratio per inmate is higher in the transferred facility. Only the transferred establishment has telemedicine resources. Attendance to primary health services is higher that in all non-transferred establishments, while the mean attendance to specialized consultation in the transferred facility doubles that of the remaining centers.

DISCUSSION

We have observed greater access to specialized care in the correctional facility managed by the community health system when compared to that of the facilities managed by Penitentiary Institutions. This statement is based on a series of effectivity indicators and results that have provided significantly improved outcome in the transferred facility.

Building Bridges for Innovation in Ageing: Synergies between Action Groups of the EIP on AHA

The Strategic Implementation Plan of the European Innovation Partnership on Active and Healthy Ageing (EIP on AHA) proposed six Action Groups. After almost three years of activity, many achievements have been obtained through commitments or collaborative work of the Action Groups. However, they have often worked in silos and, consequently, synergies between Action Groups have been proposed to strengthen the triple win of the EIP on AHA. The paper presents the methodology and current status of the Task Force on EIP on AHA synergies. Synergies are in line with the Action Groups' new Renovated Action Plan (2016-2018) to ensure that their future objectives are coherent and fully connected. The outcomes and impact of synergies are using the Monitoring and Assessment Framework for the EIP on AHA (MAFEIP). Eight proposals for synergies have been approved by the Task Force: Five cross-cutting synergies which can be used for all current and future synergies as they consider overarching domains (appropriate polypharmacy, citizen empowerment, teaching and coaching on AHA, deployment of synergies to EU regions, Responsible Research and Innovation), and three cross-cutting synergies focussing on current Action Group activities (falls, frailty, integrated care and chronic respiratory diseases).

Operational Definition of Active and Healthy Ageing (AHA): A Conceptual Framework

Health is a multi-dimensional concept, capturing how people feel and function. The broad concept of Active and Healthy Ageing was proposed by the World Health Organisation (WHO) as the process of optimizing opportunities for health to enhance quality of life as people age. It applies to both individuals and population groups. A universal Active and Healthy Ageing definition is not available and it may differ depending on the purpose of the definition and/or the questions raised. While the European Innovation Partnership on Active and Healthy Ageing (EIP on AHA) has had a major impact, a definition of Active and Healthy Ageing is urgently needed. A meeting was organised in Montpellier, France, October 20-21, 2014 as the annual conference of the EIP on AHA Reference Site MACVIA-LR (Contre les Maladies Chroniques pour un Vieillissement Actif en Languedoc Roussillon) to propose an operational definition of Active and Healthy Ageing including tools that may be used for this. The current paper describes the rationale and the process by which the aims of the meeting will be reached.

[Cross-cultural adaptation into Spanish of the Nursing Home Survey on Patient Safety Culture questionnaire]

OBJECTIVE

This article presents the first phase of a research project aimed at adapting a tool for assessing safety culture in nursing homes into Spanish.

MATERIAL AND METHODS

The Nursing Home on Patient Safety Culture of the Agency for Health Care Research and Quality was translated and culturally adapted. The International Quality of Life Assessment protocol was followed, which included, translation, conceptual equivalence evaluation, back-translation, content validity and a pilot study.

RESULTS

Three of the 42 items were modified with respect to the original version. The remaining modifications were introduced in the F Section, containing sociodemographic information and job related questions.

CONCLUSIONS

The adapted questionnaire will help to assess the level of safety of the resident culture among healthcare professionals in these centres, to identity areas for improvement, and to analyze how to evolve when organizational changes are introduced.

Lymphatic route of transport and pharmacokinetics of Micrurus fulvius (coral snake) venom in sheep

The contribution of the lymphatic system to the absorption and systemic bioavailability of Micrurus fulvius venom after subcutaneous (SC) administration was assessed using a central lymph-cannulated sheep model. Micrurus fulvius venom was administered either by intravenous bolus (IV) or subcutaneous injection (SC) in 12 sheep with and without thoracic duct cannulation and drainage. Venom concentration in serum and lymph was determined by a sandwich enzyme-linked immunosorbent assay (ELISA) in samples collected over a 6-hour period and in tissues harvested at the end of the experiment. Pharmacokinetic parameters were determined by a non-compartmental analysis. In the lymphatic cannulated group, over the 6 hours after the venom was administered, 69% of administered dose was accounted for in blood (45%) and lymph (25%). Negligible levels of venom were detected in organs and urine implying that the steady state observed after SC administration is maintained by a slow absorption process. Comparison of kinetics of the thoracic duct cannulated and non-cannulated groups showed that lymphatic absorption contributed in an important way to maintenance of this steady state. These results show that the limiting process in the pharmacokinetics of Micrurus fulvius venom following SC administration is absorption, and that the lymphatic system plays a key role in this process.

[Late effects of radiofrequency fulguration: report of five cases]

Radiofrequency fulguration is the definitive treatment of several supraventricular and ventricular arrhythmias. During radiofrequency application, the conduction in a specific zone is interrupted as a consequence of cellular necrosis and edema. The disappearance of edema, minutes or hours after the procedure, allows the reappearance of conduction and arrhythmias. On the other hand, the definitive lesion is larger than the one caused acutely, due to the progression of the scar. We report five patients, in whom there was an apparent failure of the fulguration, since at the end of the procedure there was conduction in the fulgurated zone, the tachycardia was inducible or pre excitation and arrhythmias reappeared during the follow up. All five were subjected to a new electrophysiological study and in all, fulguration had been effective. We conclude that these late effects of fulguration are due to the slow progression of fibrosis, that continues days or weeks after the procedure.

[Ventricular reentry tachycardia within the bundle branches. Report of 3 cases]

Vientricular tachycardia due to reentry within the bundle branches occurs in the presence of left ventricular dilatation and conduction alterations in the His-Purkinje system. A macro-reentry is formed by the His bundle, left and right bundles and ventricular myocardium. The anatomical substrate of this arrhythmia is ventricular dilatation. However, it may appear in healthy hearts. Alterations of intraventricular conduction are reflected by a prolongation of PR interval and bundle branch block in the surface EKG and prolongation of HV interval in the endocavitary registry. During tachycardia, His activation precedes ventricular activation. We report three patients aged 55, 58 and 78 years old with a dilated cardiomyopathy and ventricular tachycardia due to reentry within the bundle branches. All had a left bundle branch block and a prolonged HV internal. The arrhythmia was induced during the study in two patients. All were subjected to radiofrequency fulguration of the right branch of the His bundle. After fulguration, two remained with a pattern of complete right bundle branch block and one with a complete intermittent AV block. All three are free of arrhythmic events.

[Radiofrequency ablation of right accessory pathways]

BACKGROUND

Accessory pathways are muscular connections between auricles and ventricles, present in different points of mitral and tricuspid annuluses. These pathways participate in 50% of paroxysmal supraventricular tachycardias and the definitive cure of the arrhythmia is their ablation.

AIM

To report our experience in patients with right accessory pathways.

PATIENTS AND METHODS

Fifty consecutive patients treated between 1990 and 1996 are reported. Eight had a history of syncope, two had a diagnosis of Ebstein disease and 36 had a pre-excitation in the surface electrocardiogram.

RESULTS

Fifty four accessory pathways were identified, since four patients had two pathways. Twenty four pathways were posteroseptal, 15 were lateral, 9 were medioseptal and 6 were anteroseptal. One patient had also a nodal reentry tachycardia. Fulguration was attempted in 39 patients and it was finally successful in 32. Three patients required more than one session. There were six relapses and all were successfully ablated in a second session. A mean of 28 radiofrequency applications were done (range 1-76), mean laboratory time was 6 hours and mean radioscopy time was 70 min. Four patients had a transient atrioventricular conduction blockade.

CONCLUSIONS

Radiofrequency ablation of accessory pathways has a high degree of success and a low rate of complications.

Ventricular tachycardia and fibrillation in normal hearts

Although ventricular tachyarrhythmias usually occur in the setting of definable heart disease, up to 15% of ventricular tachycardias and 10% of ventricular fibrillation occur in patients without heart disease. Of the various clinical entities comprising these idiopathic ventricular tachyarrhythmias, a few well-defined clinical syndromes have been described, such as idiopathic right ventricular outflow tract tachycardia, idiopathic left posterior fascicular ventricular tachycardia, and the right bundle branch block and ST segment elevation syndrome of idiopathic ventricular fibrillation. Many advances have been made in the past few years in our understanding and treatment of idiopathic ventricular tachyarrhythmias, and these advances are the subject of this review.

[Supraventricular paroxysmal tachycardia with ventriculo-atrial dissociation. Report of one case]

Nodal reentrant supraventricular paroxysmal tachycardia corresponds to a reentry circuit established between fibers with different conduction velocities and refractory periods in the atrioventricular node. These are the slow and fast nodal pathways. That ventricular tissue does not form part of the circuit of this arrhythmia is accepted nowadays, and the involvement of atrial tissue is discussed. We report a 57 years old male with a nodal reentrant tachycardia. In the electrophysiological study he presented an atrial and ventricular dissociation during the tachycardia. These findings allow a better understanding of the electrophysiological substrate of this arrhythmia.

[Idiopathic tachycardia originated in left ventricle]

BACKGROUND

Idiopathic ventricular tachycardia occurs in patients with no structural heart disease and may originate in left of right ventricle.

AIM

To report our experience with this condition.

PATIENTS AND METHODS

We report six patients (five male), aged 35 years old as a mean, with idiopathic left ventricular tachycardia that were subjected to conventional electrophysiological studies with atrial and ventricular stimulation programs and radiofrequency fulguration, between December 1993 and May 1996.

RESULTS

The mean lapse of disease was 24 months and five patients received antiarrhythmic medications previously. All tachycardias had a morphology with an image of right bundle branch block. Radiofrequency fulguration was done after obtaining a satisfactory pace mapping of at least 11 of the 12 superficial EKG derivations. The procedure was successful in five patients and two had a relapse. One of the relapsed patients was successfully fulgurated again.

CONCLUSIONS

Radiofrequency fulguration for idiopathic ventricular tachycardias is a safe and effective therapeutic procedure.

[Cardiovascular effects of AV interval shortening with electrical stimulation in dilated cardiomyopathy]

BACKGROUND

A temporal alteration between atrial and ventricular contraction, in which the last one would be abnormally retarded, could exist in patients with dilated cardiomyopathy. This alteration could have adverse hemodynamic effects.

AIM

To study the hemodynamic modifications caused by an artificial shortening of AV interval in patients with dilated cardiomyopathy.

PATIENTS AND METHODS

Nine patients with dilated cardiomyopathy were studied. Hemodynamic and tissular perfusion values, echocardiographic and radioisotopic ventricular function parameters were measured before and after six hours of AV interval shortening with electrical stimulation of the heart.

RESULTS

After electrical stimulation, cardiac output increased from 3.38 +/- 0.8 to 3.87 +/- 0.79 l/min (p< 0.05). Pulmonary capillary pressure decreased from 23.8 +/- 8.9 to 19.8 +/- 9.2 mm Hg (p = NS). There were no significant changes in ventricular function parameters or in systemic and pulmonary pressures.

CONCLUSIONS

Electrical shortening of AV interval in patients with dilated cardiomyopathy increases cardiac output but does not change ventricular function parameters.

[Radiofrequency catheter ablation in patients with common atrial flutter]

BACKGROUND

Type 1 atrial flutter is produced by a reentry circuit located in the right atrium that can be interrupted applying radiofrequency in the inferior cava-tricuspid valve isthmus.

AIM

To report our experience in the treatment of atrial flutter with radiofrequency ablation.

PATIENTS AND METHODS

Nine patients (eight male) whose ages ranged from 6 to 72 years old were studied. Two patients had an operated congenital cardiopathy, two had high blood pressure, one was subjected previously to radiofrequency ablation due to a left paraspecific pathway, one developed a cardiac failure secondary to tachycardia and three did not have evidences of cardiopathy.

RESULTS

In two patients, atrial flutter was not interrupted. In the other seven patients, radiofrequency ablation was successful. There were three relapses in the first month after the procedure, of these, two patients were successfully treated again. After a mean follow up of 4.5 months, these patients are asymptomatic and without antiarrhythmic drugs. Analysis of obtained signals, showed that radiofrequency that interrupted atrial flutter always occurred in zones of double potentials.

CONCLUSIONS

Radiofrequency ablation is an effective treatment for atrial flutter and the zone of successful ablation is associated to the presence of double atrial potentials.

[Radiofrequency fulguration for supraventricular tachycardia in pediatrics]

Supraventricular tachycardias (SVT) are the most frequent cause of tachycardia in children. Its pharmacological treatment has adverse effects, is not curative, and is not always effective. During the last few years radiofrequency ablation (RF-A) has changed the treatment. The purpose of this study is to evaluate our experience in RF-A in children with SVT. Between 1990 and 1995, 92 patients (1 month to 17 years old) underwent electrophysiological study after the diagnosis of SVT. RF-A was attempted in 55 patients with accessory pathways (AP), slow-pathway of the atrioventricular node, or ectopic focus. The site of ablation was decided according to the electrical signals and the catheter position. The success of the RF-A was confirmed by the interruption of the tachycardia, the change in the sequence of activation of the intracardiac signals, the regression of the preexcitation, and the inability to reinduce tachycardia. RF-A was successful in 81% of the patients; 88% in those with a left AP, 56% in those with a right AP, and 100% in those with nodal reentry. Complications were seen in 7% of the patients: 3 with arterial obstruction, one with a minimal pneumothorax, and one with cardiac tamponade. During a follow up of 16.6 months there was no relapse nor late complications. We conclude that RF-A is a safe and effective procedure in pediatric patients with SVT.

[Fulguration with radiofrequency of the slow nodal pathway: experience in 30 consecutive cases]

Atrioventricular nodal reentry tachycardia (AVNRT) is one of the most frequent mechanisms of paroxysmal supraventricular tachycardia. In these patients tachycardia is maintained due to anterograde conduction through a slow pathway and retrograde conduction to the atrium via a fast pathway. We present herein our experience in ablation of the slow pathway. Since January 1993, 30 consecutive patients with AVNRT underwent attempted catheter ablation of the slow pathway. Mean age was 35 +/- 3.7 years. All patients had symptomatic tachycardia and six had history of syncope. Electrophysiologic studies revealed AVNRT in all patients, in addition, two patients had a left accessory pathway. Slow pathway ablation was performed with a Mansfield 7 F catheter, guided by both fluoroscopic positioning and endocardial signals. A mean of 13 bursts were applied. In the 30 patients conduction through the slow pathway was interrupted, and thus tachycardia was no longer inducible. Retrograde conduction post ablation was evaluated in 17 of the 30 patients, significant changes were observed in three of them. One patient developed second degree AV block and a permanent pacemaker was implanted. Another patient had recurrence of tachycardia three months post ablation. After a second attempt she is arrhythmia free. Patients have been followed for a mean of 15.7 +/- 2.5 months and are asymptomatic in the absence of antiarrhythmic therapy.

[Junctional reciprocating tachycardia: clinical and electrophysiological characteristics, and the role of fulguration in 5 cases]

The permanent form is a variety of junctional reciprocating tachycardia that is refractory to medical treatment. The anterograde arm of the circuit is formed by the His Purkinje bundle and the retrograde conduction is through a slow conduction Accessory Atrioventricular Pathway. We report five patients with this type of arrhythmia, subjected to electrophysiological assessment. Their mean age was 37 years, all suffered from palpitations and several medical treatments had failed. During tachycardia, electrocardiogram had a negative P wave in inferior leads and RP interval was bigger than PR interval. Accessory Pathway were located in the right postero-septal region in three patients, in the left postero-septal region in one and in the left lateral in one. Specific bundle fulguration was successfully attempted in four patients, in whom arrhythmias did not recur without medical treatment.

[Diltiazem versus intravenous nitroglycerin in the treatment of unstable angina pectoris. A randomized study]

Prognosis of unstable angina pectoris is related to admission EKG changes and prompt symptom control. The aim of this study was to compare the clinical effects of intravenous diltiazem (DTZ) or nitroglycerin (NTG) in patients with unstable angina pectoris. We studied 43 patients admitted to the hospital with a history of rest angina within the last 48 hours, associated with EKG evidence of ischemia. All subjects received intravenous heparin and oral aspirin, 23 were randomly assigned to receive intravenous DTZ and 20 to receive intravenous NTG. Both groups had similar baseline features and the endpoints of treatment were recurrence of angina, myocardial infarction, death during hospitalization and secondary side effects. Treatment with DTZ, when compared to NTG, resulted in a significant reduction of recurrent angina (8.7 and 59% respectively; p < 0.005), number of angina episodes per patient (0.18 +/- 0.5 and 0.9 +/- 1.2 respectively; p < 0.05) and lower need for dose increment to control symptoms (3 and 9 patients respectively; p < 0.05). The most common side effects observed were cephalea with NTG (60% of patients) and asymptomatic sinus bradicardia with DTZ (28% of patients). In each group, one patient had a myocardial infarction and one patient died. It is concluded that intravenous DTZ reduces myocardial ischemia to a greater extent than NTG and can be safely used in patients with unstable angina pectoris.

[Arrhythmogenic right ventricular dysplasia. Options of treatment during a 12-year follow-up of a patient]

The replacement of muscle by fibrous and adipose tissue leads to arrhythmogenic right ventricular dysplasia. We report the clinical features and therapeutic options of a 50 years old male with the disease followed during 12 years. The latter included pharmacological therapy, surgical pseudoaneurysmal resection and radiofrequency fulguration of a second arrhythmogenic focus that appeared 10 after the surgical procedure. The patient remained asymptomatic after each therapy, until the disease progressed again. This follow up is one of the longest reported and documents the disease's clinical presentation, evolution and treatment.

[Hypertrophic cardiomyopathy with two episodes of recuperated sudden death. Report of the first implantable defibrillator cardioverter inserted in Chile]

We report a 29 years old male with a non obstructive hypertrophic cardiomyopathy that survived two episodes of cardiac arrest and with a familiar history of the disease and sudden death. He had an implant of an automatic implantable cardioverter defibrillator by a left anterior thoracotomy with intraoperative electrophysiology. The postoperative outcome was uneventful. After one year of follow up, the patient is in good functional capacity and the implanted device has not performed defibrillations.

[Radiofrequency fulguration of accessory pathways]

Between August 1991 and August 1993, 75 patients (42 male) with Wolff Parkinson White syndrome (43 concealed) were subjected to radiofrequency ablation of accessory pathways at our institution. 55 had left, 8 postero septal, 2 anteroseptal and 10 right accessory pathways. A retrograde aortic technique with placement of the ablation catheter in close proximity to the mitral annulus was used for most of the patients with left accessory pathways and for some with posteroseptal pathways. The right, anteroseptal and some posteroseptal pathways were ablated using a right heart approach placing the ablation catheter in the tricuspid annulus. Ablation was successful in 61 patients (81%). One subject developed a fatal cardiac tamponade after a transeptal catheterization and was unrelated to the ablation per se. It is concluded that radiofrequency ablation of accessory pathways is a curative procedure for a great majority of patients with Wolf Parkinson White syndrome.

Natural history of spinal cord infarction caused by nucleus pulposus embolism

Nucleus pulposus embolism causing spinal cord infarction is exceptional. A 16-year-old girl was seen with sudden onset of interscapular pain and paraplegia from fatal ischemic transverse myelopathy due to arterial and venous occlusions by fibrocartilaginous embolism. In 32 cases of nucleus pulposus embolism, females predominated (69%) and age distribution was bimodal with peaks at 22 and 60 years (median, 38.5). Embolization was either arterial and venous (50%) or purely arterial (50%). Myelopathy predominated in cervical (69%) and lumbosacral (22%) segments. Schmorl's nodes, larger volume and vascularization of nucleus pulposus in the young, and spinal arteriovenous communications, trauma, and degenerative changes in older patients could be important pathogenetic factors. Diagnosis requires histopathologic confirmation. Nucleus pulposus embolism may be an underlying cause in cases diagnosed as transverse myelitis and ischemic infarction of spinal cord.

Acute ischemic stroke from fibrocartilaginous embolism to the middle cerebral artery

BACKGROUND AND PURPOSE

Fibrocartilaginous embolism from the nucleus pulposus has been reported as a rare cause of spinal cord ischemia. We were unable to find previous reports of embolism from this source to cerebral arteries.

CASE DESCRIPTION

A previously healthy 17-year-old girl fell during a basketball game. Left hemiparesis and unresponsiveness developed followed by signs of right uncal herniation and death over a 3-day period. There was no evidence of neck, head, or spine trauma, and cardiac evaluation was normal. Neuropathological examination showed extensive ischemic infarction of the right middle cerebral artery territory, brain edema, and herniation. Complete embolic occlusion of the right middle cerebral artery by fibrocartilaginous material, consistent with nucleus pulposus, was documented. Small, terminal coronary artery branches also showed embolism by the same material and limited areas of myocardial infarction.

CONCLUSIONS

Acute cerebral embolism after minor trauma in a young patient may be rarely due to fibrocartilaginous embolism from the nucleus pulposus. The pathogenesis of this problem remains poorly understood, but systemic embolism appeared to have occurred in this case.

[Polymorphic reticulosis: a type of lymphoma? Report of 3 cases]

Three patients seen at the Medicine Department of Del Salvador Hospital between 1986 and 1990 are reported. All had a history of purulent or bloody nasal discharge and recurrent sinusitis, before the appearance of progressive and painful destructive phenomena that affected the rhino faucial region. The diagnosis was made with the histopathological study that disclosed and angiocentric polymorphic infiltrates and perivascular necrosis. The three patients received similar treatment consistent in prednisone 1 mg/kg/day per os, cyclophosphamide 2 mg/kg/day per os and local radiotherapy. The response to therapy was bad and survival was less than three months. It is concluded that although this entity is infrequent, its severity requires and aggressive workup and management by a multidisciplinary team. Notwithstanding the mortality remains to be high.

Wilson's disease, a reversible dementia: case report

A case of advanced Wilson's disease with clear dementing features is presented. Neuropsychological evaluation before treatment revealed intellectual deterioration particularly in memory and performance tasks. The patient was treated with Penicillamine, a copper-chelating agent, for 7 months, with notable improvement in her dementia and in her motor signs. A second battery of neuropsychological tests demonstrated the improvement in the mental aspects. These findings support the concept of Wilson's disease being a reversible dementia.

Ventral root nonmedullated fibers: proportion, calibers, and microtubular content

Proportion, caliber, and microtubular content of the L7 ventral root nonmedullated fibers were studied in the cat. Nonmedullated fibers constituted 28% of the axonal population at the far end of the root. The number of myelinated profiles at the far end of the root and in the vicinity of the ventral surface of the cord (1-2 mm distance) was the same whereas the number of nonmedullated fibers decreased toward the proximal site of the root by 42%. Caliber and microtubular content of nonmedullated fibers were assessed only at the far end of the ventral root. Nearly 90% of the axons were smaller than 0.3 micron2. The average cross-sectional area was 0.15 micron2, a value 35% below that of the L7 dorsal root fibers. The microtubular density was highest in the finest fibers (116 microtubules/micron2 in fibers smaller than 0.1 micron2) and decreased with the increase in cross-sectional area (25 microtubules/micron2 for 0.7-0.8 micron2 axons). The number of microtubules per axon in axons of both roots was similar in fibers smaller than 0.3 micron2; in larger axons, composing about 10% of the population, ventral root fibers had more microtubules than dorsal root fibers. The ventral and dorsal nonmedullated fibers differ slightly but significantly in caliber and microtubule content. However, they are similar in contrast to peripheral nonmedullated fibers, which are three to four times as big and contain two to three times as many microtubules as radicular fibers. Our results confirm the presence of a large admixture of nonmedullated profiles in the L7 ventral root of the cat, support the notion that a number of these fibers make a U turn in the ventral root, and suggest that these arise from the central process of the primary sensory axon.

Topography of the hemi-inattention syndrome

The hemi-inattention syndrome was studied in 15 right-handed adults, 12 men and 3 women. One patient had a pontic-mesencephalic lesion, 3 had right hemisphere damage, 7 had left-hemisphere lesion and 4 had bilateral lesions. All lesions were confirmed by CT-scan. Different criteria of hemi-inattention were used. All patients presented extinction, inattention and in 13 visuomotor akinesia; 5 of the left and all of the right and bilateral lesion patients presented spatial neglect. CT-scans were superimposed. The posterior parietal region was the most important in producing contralateral hemi-inattention. Results are discussed with relation to the literature and the educational factor and cerebral asymmetry are discussed with regard to hemi-inattention.

Neuroparalytic accidents of antirabies vaccination with suckling mouse brain vaccine. Clinical and pathologic study of 21 cases

Twenty-one cases of neuroparalytic accidents of rabies vaccination (with suckling mouse brain vaccine), 11 of them fatal, were observed, occurring predominantly in men; the mean age of the patients was 29 years. On the average, 13 doses of the vaccine were used. Only three patients received less than seven doses. The mean latent period was 14 days (range, 4 to 24 days). In 16 patients (76%), a Guillain-Barré syndrome occurred that was moderate in three, severe in seven, and fatal in six. Pathologically, this was shown to be a typical polyradiculoneuritis. Five patients had fatal involvement of the central nervous system. Three had an acute disseminated perivenous leukoencephalopathy, with concurrent rabies encephalitis in one case. One patient had a perivenous myeloradiculopathy and one a chronic encephalomyelopathy of six years' duration with demyelinating plaques in the periventricular white matter, cerebellum, and spinal cord. Since the reduction of postexposure rabies vaccination to seven doses, no new cases have been observed in Colombia.