Intervenciones cognitivas a través de realidad virtual en personas con Deterioro Cognitivo Leve: Una Revisión Sistemática

Introducción: La posibilidad de reversión del Deterioro Cognitivo Leve (DCL) ha generado diversas investigaciones en búsqueda de tratamiento, entre ellas la estimulación cognitiva a través de realidad virtual (RV). No obstante su uso, no existe aún evidencia acerca de las modalidades y efectos en personas con DCL. Objetivo: Sistematizar las características de los estudios que han utilizado intervenciones cognitivas con RV en personas con DCL, describir sus efectos y establecer recomendaciones para futuras investigaciones en base a las limitaciones reportadas. Métodos: revisión sistemática de estudios publicados entre 2010 y 2020, en las bases de datos Web of Science, Scopus y Pubmed. Resultados: Se identificaron 14 estudios con programas que emplearon mayoritariamente RV de tipo inmersiva, con el "supermercado" como escenario virtual más frecuente. En siete trabajos se intervino una función cognitiva, siendo la memoria y las funciones ejecutivas las más intervenidas. Los instrumentos de evaluación se concentraron en medidas cognitivas, con escasa evaluación de variables neuropsiquiátricas y de calidad de vida. Trece estudios informaron mejoras a nivel cognitivo general o por dominio específico. Conclusiones: La utilización de RV, inmersiva y no inmersiva, ha tenido resultados positivos en el rendimiento cognitivo general o específico por dominio, de personas con DCL, sin embargo, debido a la incipiente y limitada evidencia de su uso en personas con esta patología, no es posible determinar la sostenibilidad de estos resultados y la generalización de estas intervenciones hacia las actividades de la vida diaria. Se recomienda realizar intervenciones con entornos reales y seguimiento post-intervención.

Introduction: The possibility of Mild Cognitive Impairment (MCI) reversal has generated numerous studies in search of treatment, including cognitive stimulation through virtual reality (VR). Despite its use, there is still no evidence about the modalities and effects in people with MCI. Aim: To systematize the characteristics of the studies that have used cognitive interventions with VR cognitive in people with MCI, describe their effects and to establish recommendations for future research based on the limitations reported. Methods: systematic review of studies published between 2010 and 2020, in the Web of Science, Scopus and Pubmed databases. Results: 14 studies were identified with programs that mostly used immersive VR, with the "supermarket" as the most frequent virtual scenario. In seven studies only one cognitive function was involved, with memory and executive functions being the most intervened. The assessment instruments focused on cognitive measures, with little assessment of neuropsychiatric and quality of life variables. Thirteen studies reported improvements on the general cognitive level or by specific domain. Conclusions: The use of immersive and non-immersive VR has had positive results in the general or domain-specific cognitive performance of people with MCI, however, due to the incipient and limited evidence of its use in people with this pathology, it is not possible to determine the sustainability of these results and the generalization of these interventions regarding daily living activities. Interventions with real environments and post-intervention follow-up are recommended.

Variables psicológicas y su relación con la evolución del índice de masa corporal en personas sometidas a cirugía bariátrica / Psychological variables and their relationship with the evolution of the body mass index in people undergoing bariatric surgery

Resumen Introducción La cirugía bariátrica es una de las opciones efectivas para la reducción del peso corporal, sin embargo, no existe claridad respecto de la evolución de la baja de peso corporal, más aún, algunos hallazgos sugieren amplia variabilidad individual en la curva de variación del Índice de Masa Corporal (IMC). Los factores asociados a este fenómeno no son claros aún. Objetivo Esta investigación buscó identificar la influencia de factores psicológicos: autoeficacia alimentaria, patrones de alimentación y apoyo social percibido, en la variación del IMC en pacientes sometidos a cirugía bariátrica. Materiales y Método Participaron 31 pacientes intervenidos en un hospital público del sur de Chile. Se utilizó la curva de crecimiento de Gompertz para modelar las curvas de variación de IMC y regresión no lineal para conocer la influencia de las variables de estudio. Resultados El porcentaje máximo de reducción de IMC, se produjo al noveno mes tras la cirugía. El IMC de inicio mostró una influencia significativa en la reducción del IMC (p = 0,04) lo mismo que el apoyo social percibido, subfactor amigos (p = 0,03). Las variables psicológicas estudiadas, tratadas individualmente, no afectaron la curva de variación de IMC, sin embargo, tratadas de modo agrupado lograron predecir el porcentaje máximo de reducción de IMC y su velocidad, incluso controlando el IMC de inicio. Discusión: Se confirman hallazgos previos respecto de que la variabilidad individual en la evolución del IMC postcirugía se ve afectada por factores psicológicos. Conclusión Variables psicológicas y no exclusivamente biomédicas, inciden en la evolución del IMC postcirugía, por lo que se sugiere atender a estos aspectos, tanto en la evaluación prequirúrgica como en el seguimiento postcirugía.

Background Bariatric surgery is one of the effective options for the reduction of body weight, however, there is no clarity regarding the postoperative weight loss curve, moreover, there are findings that suggest wide individual variability and the factors associated with this phenomenon are not clear yet. Aim This study sought to identify the influence of psychological factors such as eating self-efficacy, eating patterns and social support on the variation of BMI in patients who have undergone bariatric surgery through the surgical technique of vertical sleeve gastrectomy. Materials and Method A total of 31 operated patients in a public hospital in southern Chile participated in the study. The Gompertz growth curve was used to model BMI variation curves and nonlinear regression to ascertain the influence of the study variables. Results The maximum weight loss occurs around the ninth month after surgery. The initial BMI shows a significant difference in the reduction of BMI (p = 0.04) as well as the social support perceived and the sub-factor friends (p = 0.03). The psychological variables, treated individually, had no effect on the weight variation curve; however, when treated as a group, they were able to predict the maximum of weight loss and its speed, even controlling for the initial BMI. Discussion According to previous studies, these findings confirm that the individual variability in the evolution of BMI after surgery is affected by psychosocial factors. Conclusion Pre-surgical assessment and post-surgery follow-up are recommended, taking into account not only biomedical variables but also psychological factors.

Percepción de autoeficacia y rendimiento en tareas de memoria operativa: Comparación entre adultos mayores y jóvenes / Perception of self-efficacy and actual performance in working memory tasks: A comparison between older and younger adults

Resumen La vejez se ha caracterizado por la existencia de una declinación natural de la memoria, como asimismo de su autoeficacia. La relación entre ambas ha sido objeto de varias investigaciones que confirman que la autoeficacia de la memoria afecta el rendimiento en tareas de memoria. Sin embargo, existe un grupo menor de investigaciones donde no se presenta dicha relación. El objetivo del estudio fue comparar la percepción de autoeficacia de la memoria con el rendimiento en tareas de memoria en adultos mayores y jóvenes. Los participantes fueron 200 adultos mayores y 111 jóvenes universitarios quienes respondieron dos instrumentos: uno de percepción de autoeficacia de memoria, y otro de rendimiento en tareas memoria operativa y/o memoria de corto plazo, ambos instrumentos fueron construidos y adaptados de forma tal que fueran comparables entre sí. Los resultados muestran que los adultos mayores presentan un menor rendimiento en casi todas las tareas de memoria y una leve superioridad en la percepción de autoeficacia de la memoria, existe una relación significativa entre ambas medicinas. En cambio, en los jóvenes su percepción de autoeficacia fue levemente inferior, pero su rendimiento fue superior.

Aging has been characterized by a natural decline of memory, as well as by a decline in the perception of memory self-efficacy. The relationship between these two variables has been the subject of several studies, confirming that the perception of mnemonic self-efficacy affects actual performance on memory tasks. However, there is a smaller group of studies where this relationship has not been found. The objective of the present study was to compare the perception of self-efficacy of memory with performance in memory tasks in older and younger adults. Two hundred older adults and 111 university students participated in the study by responding two instruments: one Perception of Memory Self-Efficacy, and another one on Performance in Operational Memory tasks. Both instruments were constructed and adapted so that they be comparable. The results showed that older adults have a lower performance in almost all memory tasks and a slight superiority in the perception of memory self-efficacy, and a significant relationship was found between the two. On the other hand, in younger people's beliefs about their memory were slightly lower, but they performed better.

Schwannoma of the eyelid. A case report. / Schwannoma de párpado, a propósito de un caso.

The case is presented of a 57 year-old man with a one-year history of enlargement of the left upper eyelid. An excisional biopsy was performed, and the histological and immunohistochemical study confirmed the diagnosis of schwannoma. Schwannomas are benign peripheral nerve sheath tumours, derived from a Schwann cells proliferation. Eyelid involvement is extremely uncommon. To make the diagnosis, a detailed histopathological and immunohistochemical study is essential. This case suggests that schwannomas should be included within the differential diagnosis of any solid eyelid lesion.

Percepción de autoeficacia y rendimiento en tareas de memoria operativa: comparación entre adultos mayores y jóvenes / Perception of self-efficacy and actual performance in working memory tasks: a comparison between older and younger adults

Resumen La vejez se ha caracterizado por la existencia de una declinación natural de la memoria, como asimismo de su autoeficacia. La relación entre ambas ha sido objeto de varias investigaciones que confirman que la autoeficacia de la memoria afecta el rendimiento en tareas de memoria. Sin embargo, existe un grupo menor de investigaciones donde no se presenta dicha relación. El objetivo del estudio fue comparar la percepción de autoeficacia de la memoria con el rendimiento en tareas de memoria en adultos mayores y jóvenes. Los participantes fueron 200 adultos mayores y 111 jóvenes universitarios quienes respondieron dos instrumentos: uno de percepción de autoeficacia de memoria, y otro de rendimiento en tareas memoria operativa y/o memoria de corto plazo, ambos instrumentos fueron construidos y adaptados de forma tal que fueran comparables entre sí. Los resultados muestran que los adultos mayores presentan un menor rendimiento en casi todas las tareas de memoria y una leve superioridad en la percepción de autoeficacia de la memoria, existe una relación significativa entre ambas medicines. En cambio, en los jóvenes su percepción de autoeficacia fue levemente inferior, pero su rendimiento fue superior.

Aging has been characterized by a natural decline of memory, as well as by a decline in the perception of memory self-efficacy. The relationship between these two variables has been the subject of several studies, confirming that the perception of mnemonic self-efficacy affects actual performance on memory tasks. However, there is a smaller group of studies where this relationship has not been found. The objective of the present study was to compare the perception of self-efficacy of memory with performance in memory tasks in older and younger adults. Two hundred older adults and 111 university students participated in the study by responding two instruments: one Perception of Memory Self-Efficacy, and another one on Performance in Operational Memory tasks. Both instruments were constructed and adapted so that they be comparable. The results showed that older adults have a lower performance in almost all memory tasks and a slight superiority in the perception of memory self-efficacy, and a significant relationship was found between the two. On the other hand, in younger people's beliefs about their memory were slightly lower, but they performed better.

Retinitis pigmentosa unilateral a propósito de un caso / Unilateral retinitis pigmentosa. A case report

Caso clínico: Mujer de 27 años con historia de nictalopía y constricción de campo visual del ojo derecho. El examen oftalmológico, campo visual y electrorretinograma (ERG) fueron compatibles con una retinitis pigmentosa (RP) unilateral. Al seguimiento de un año, permanecía la afección unilateral. Discusión: La RP unilateral es un trastorno infrecuente, con una frecuencia entre el 0,2-5% de las RP. Afecta principalmente a mujeres, y en edades más avanzadas que las bilaterales. Para dar un diagnóstico definitivo tiene que haber un fondo de ojo y ERG alterados unilateralmente, y excluir causas infecciosas, inflamatorias y vasculares (AU)

Clinical case: A 27-year-old woman with a history of nyctalopia and constriction of visual field of the right eye. The ophthalmological examination showed a visual field and electroretinogram that were compatible with unilateral retinitis pigmentosa (RP). After a one year follow-up, the unilateral condition remained. Discussion: Unilateral retinitis pigmentosa is a rare condition, with a frequency between 0.2%-5% of the RP. It mainly affects women and older age groups than bilateral RP. For a definitive diagnosis, it is necessary to have a funduscopy and electroretinogram (ERG) altered unilaterally, and exclude infectious, inflammatory, and vascular causes (AU)

Unilateral retinitis pigmentosa. A case report. / Retinitis pigmentosa unilateral a propósito de un caso.

CLINICAL CASE: A 27-year-old woman with a history of nyctalopia and constriction of visual field of the right eye. The ophthalmological examination showed a visual field and electroretinogram that were compatible with unilateral retinitis pigmentosa (RP). After a one year follow-up, the unilateral condition remained. DISCUSSION: Unilateral retinitis pigmentosa is a rare condition, with a frequency between 0.2%-5% of the RP. It mainly affects women and older age groups than bilateral RP. For a definitive diagnosis, it is necessary to have a funduscopy and electroretinogram (ERG) altered unilaterally, and exclude infectious, inflammatory, and vascular causes.

Rocuronium pharmacokinetics and pharmacodynamics in the adductor pollicis and masseter muscles.

BACKGROUND: The aim of this study was to characterize the dose-effect relationship of rocuronium at the adductor pollicis and masseter muscles. METHODS: Ten, ASA I, adult patients, received a bolus dose of rocuronium 0.3 mg/kg during propofol based anesthesia. Train-of-four (TOF) was simultaneously monitored at the masseter and the adductor pollicis muscles until recovery. Rocuronium arterial serum concentrations were measured during 120 min. The first twitch of the TOF response was used to characterize the time-effect profile of both muscles using pharmacokinetic-pharmacodynamic analysis in NONMEM. A decrease in NONMEM objective function (∆OFV) of 3.84 points for an added parameter was considered significant at the 0.05 level. RESULTS: Onset time at the masseter (mean ± SD, 1.5 ± 0.9 min) was faster than at the adductor pollicis (2.7 ± 1.4 min, P < 0.05). Recovery, measured as the time to TOF ratio = 0.9 was similar between muscles 29.9 ± 6.7 (adductor pollicis) vs. 29.3 ± 8.1 (masseter). (P = 0.77). The estimated pharmacodynamic parameters [mean (95% CI)] of the adductor pollicis muscle and the masseter muscle were; plasma effect-site equilibration half-time (teq) 3.25 (2.34, 3.69) min vs. 2.86 (1.83, 3.29) min, (∆OFV 383.665); Ce50 of 1.24 (1.13, 1.56) mg/l vs. 1.19 (1.00, 1.21) mg/l, (∆OFV 184.284); Hill coefficient of 3.97 (3.82, 5.62) vs. 4.68 (3.83, 5.71), (∆OFV 78.906). CONCLUSIONS: We found that the masseter muscle has faster onset of blockade and similar recovery profile than adductor pollicis muscle. These findings were best, explained by a faster plasma effect-site equilibration of the masseter muscle to rocuronium.

Percepción de mujeres consultantes de atención primaria sobre el abandono del tratamiento de depresión / Perception of female patients in a primary care service regarding quitting the treatment of depression

El tratamiento oportuno de los trastornos depresivos es considerado una prioridad sanitaria. Un obstáculo en el logro de este propósito es la baja adherencia o el abandono del tratamiento que realizan algunos consultantes. El objetivo de esta investigación fue comprender la percepción de personas que desertaron de su tratamiento en atención primaria respecto de los factores que motivaron ese abandono. Investigación de orientación cualitativa. Las participantes fueron mujeres entre 18 y 65 años, diagnosticadas de depresión, que ingresaron y abandonaron el Programa Nacional de Diagnóstico y Tratamiento de Depresión en el primer semestre del año 2008 y año 2009 en dos centros de salud familiar de la Octava Región, Chile. Se realizaron 15 entrevistas en profundidad semiestructuradas. las que fueron codifcadas y analizadas a través del método de comparación constante. Las principales razones de abandono del tratamiento se concentraron en la existencia de obstáculos en el acceso o continuidad de la atención y en aspectos relacionados con una percepción negativa del tratamiento recibido, especialmente del farmacológico, pero también del psicológico. Se observó en las consultantes que su implicación en el tratamiento era baja debido a desconocimiento del diagnóstico recibido o una discordancia entre el tratamiento recibido respecto a sus expectativas y creencias. Estos resultados indican que los profesionales de la enfermería podrían tener un rol clave en favorecer la permanencia de los consultantes en el tratamiento al poner una mayor consideración de las expectativas, creencias y necesidades de los propios consultantes.

Early treatment of depressive disorders is considered a health priority. One obstacle in achieving this purpose is the low adherence or abandonment of treatment performed by some consultants. The aim of this research is to understand the perception of people who deserted their treatment in primary care settings on the factors that led to the abandonment. The research uses an inductive strategy and qualitative approach as methodological basis. Participants were women aged 18 to 65 years, diagnosed with depression, who entered and left the National Program for Diagnosis and Treatment of Depression in the first half of 2008 and 2009 in two family care centers at the 8th Region, Chile. A total of 15 in-depth interviews were conducted and thereafter analyzed using the constant comparison method. The reasons for the abandonment referred to obstacles in the access and lack of continuity in the treatment, as well as factors related to negative perception of the treatment not only the pharmacological but also the psychological one. It was observed that consultants´ involvement in treatment was low due to scarce knowledge of their diagnosis received or a discrepancy between the treatment received regarding their expectations and beliefs. These results indicate that nurses could play a key role in improving the adherence to the treatment by considering patients’ expectations, beliefs and needs.

Relation between genetic markers of drug resistance and susceptibility profile of clinical Neisseria gonorrhoeae strains.

The main goal of this work is to clarify the predictive value of known genetic markers of Neisseria gonorrhoeae resistance to penicillin, tetracycline, and fluoroquinolones. The correlation between the presence of certain genetic markers and susceptibility of N. gonorrhoeae isolates to penicillin, tetracycline, and fluoroquinolones has been analyzed by means of statistical methods. Susceptibility testing with penicillin, tetracycline, and fluoroquinolones was performed by the agar dilution method. N. gonorrhoeae genomic DNA was isolated. The presence of bla(TEM-1) and tet(M) genes was analyzed by PCR. A novel method of polymorphism discovery based on a minisequencing reaction followed by matrix-assisted laser desorption ionization-time-of-flight mass spectrometry was applied for the analysis of chromosomal N. gonorrhoeae genes involved in antimicrobial resistance development. Clinical N. gonorrhoeae isolates (n = 464) were collected. Susceptibility levels to penicillin, tetracycline, and fluoroquinolones were found to be 25.9%, 35.9%, and 54.1%, respectively. Among the 19 N. gonorrhoeae isolates with penicillin MICs of > or =4 microg/ml, the bla(TEM-1) gene was detected in 12. The Tet(M) determinant was found in 4 of 12 N. gonorrhoeae isolates with tetracycline MICs of > or =16 microg/ml. The chromosomal genetic markers of penicillin and tetracycline resistance were detected especially in isolates with penicillin MICs of 0.25 to 2.0 microg/ml and tetracycline MICs of 0.5 to 4 microg/ml. Mutations in GyrA and ParC were found in 208 of 211 quinolone-resistant N. gonorrhoeae isolates. This work is the first representative molecular research of the N. gonorrhoeae population in Russia. Information about the prevalence of antibiotic resistance mechanisms and the positive predictive value of certain genetic determinants is given. The positive predictive values of the analyzed genetic markers were found to be different for fluoroquinolones (90.3%), penicillin (91.1%), and tetracycline (81.9%).

Estimation of the plasma effect-site equilibration rate constant (ke0) of rocuronium by the time of maximum effect: a comparison with non-parametric and parametric approaches.

BACKGROUND: The first order plasma-effect-site equilibration rate constant (k(e0)) links the pharmacokinetics (PK) and pharmacodynamics (PD) of a given drug. For the calculation of the k(e0), one method uses a single point of the response curve corresponding to the time to peak effect of a drug (t(peak)); however, it has not been validated. This study compares the k(e0) calculated with the method of t(peak) and the k(e0) calculated with traditional non-parametric and parametric methods. METHODS: Fifteen adult patients receiving total intravenous anaesthesia (TIVA) were studied. All patients were monitored with an NMT Monitor 221 (GE Healthcare, Helsinki, Finland) to obtain the evoked compound EMG of the adductor pollicis to a train-of-four stimuli at 10 s intervals. During TIVA, rocuronium 0.15 mg kg(-1) was given i.v. as a bolus, and the neuromuscular response was recorded until recovery from block. Using the t(peak) and the complete response curve, k(e0) of rocuronium was calculated with the three methods using the predicted plasma concentrations of rocuronium from a PK model. Values of k(e0) are median (range). RESULTS: The k(e0)s obtained were 0.19 min(-1) (0.09-0.72) with the 't(peak)' method, 0.20 min(-1) (0.14-0.44) with the non-parametric method, and 0.19 min(-1) (0.11-0.38) [typical value (range)] with the parametric method (NS). CONCLUSIONS: If the t(peak) can be adequately estimated from the data, the 't(peak) method' is a valid alternative to traditional methods to calculate the k(e0).

[Neuraxial analgesia during labor in a patient with Arnold-Chiari type I malformation and syringomyelia]. / Malformación de arnold-chiari tipo I con siringomielia, trabajo de parto y analgesia neuroaxial.

Chiari type I malformation is a caudal displacement of the cerebellum with tonsillar herniation through the foramen magnum, frequently associated with syringomyelia, a syndrome characterized by cyst-like cavities in the spinal cord; each of the conditions leads to characteristic neurologic abnormalities. Pregnant patients with these types of malformation are considered to have an increased risk of brainstem compression and/or progression of the disease during labor. We present the case of a patient in labor with a diagnosis of syringomyelia associated with Chiari type I malformation and describe the anesthetic management. The patient revealed during labor that she had syringomyelia associated with Chiari type I malformation, after having made no mention of it in previous history taking. Finally, we review the pathology observed in these patients.

Malformación de Arnold-Chiari tipo I con siringomielia, trabajo de parto y analgesia neuroaxial / Neuraxial analgesia during labor in a patient with Arnold-Chiari type I malformation and syringomyelia

La malformación de Chiari tipo I es un desplazamientocaudal del cerebelo con herniación amigdalinapor debajo del foramen magno, frecuentemente asociadocon la siringomielia, un síndrome caracterizado por lapresencia de cavidades quísticas dentro de la médulaespinal; cada una de las cuales produce alteraciones neurológicascaracterísticas. Se considera que las pacientesembarazadas con este tipo de malformaciones tienen unriesgo aumentado de enclavamiento y/o progresión de laenfermedad durante el trabajo de parto. Presentamos elcaso de una paciente en trabajo de parto con el diagnósticode siringomielia con una malformación de Chiaritipo I asociada y el manejo anestésico. Al ingreso no refirióantecedentes, sin embargo, durante el parto reveló elhecho de tener una siringomielia y malformación deChiari tipo I asociada. Finalmente, realizamos una revisiónde la patología en esta población en particular

Chiari type I malformation is a caudal displacement of ;;the cerebellum with tonsillar herniation through the ;;foramen magnum, frequently associated with syringomyelia, ;;a syndrome characterized by cyst-like cavities in the spinal ;;cord; each of the conditions leads to characteristic neurologic ;;abnormalities. Pregnant patients with these types of ;;malformation are considered to have an increased risk of ;;brainstem compression and/or progression of the disease ;;during labor. We present the case of a patient in labor with ;;a diagnosis of syringomyelia associated with Chiari type I ;;malformation and describe the anesthetic management. The ;;patient revealed during labor that she had syringomyelia ;;associated with Chiari type I malformation, after having ;;made no mention of it in previous history taking. Finally, we ;;review the pathology observed in these patients

Reversible nitrous oxide myelopathy and a polymorphism in the gene encoding 5,10-methylenetetrahydrofolate reductase.

We present a case of a patient who received nitrous oxide on two occasions within a period of 8 weeks and who subsequently developed a diffuse myelopathy, characterized by upper extremity paresis, lower extremity paraplegia and neurogenic bladder. Laboratory testing revealed hyperhomocysteinaemia and low levels of vitamin B(12). Because of this uncommon clinical presentation, we analysed the patient's DNA, and found a polymorphism in the MTHFR gene that is associated with the thermolabile isoform of the 5,10-methylenetetrahydrofolate reductase enzyme, which explained the myelopathy experienced by the patient after being exposed to nitrous oxide. Soon after initiating supplementary therapy with folic acid and vitamin B(12), the neurological symptoms subsided.

[Current prevalence of trichinosis in Santiago, Chile (1992). A study on 500 corpses]. / Prevalencia actual de la triquinosis en Santiago, Chile (1992). Estudio en 500 cadáveres.

In August-December 1992, 500 diaphragm muscle samples taken at random from people who were autopsied at the Santiago Medico-Legal Service, were submitted to phototrichinoscopy to search for encysted larvae of Trichinella spiralis. For each sample seven small pieces were examined. Three hundred and eighty nine (77.8%) cadavers corresponded to males and one hundred and eleven (22.2%) to females. Ages ranged from 1 to 90 years. Ten (2.0%) of the individuals examined resulted positive, the higher frequencies corresponding to individuals over 20 years of age. The prevalence rate of T. spiralis infection found is rather similar to those detected in 1966-1967, 1972 and 1982, with percentages of 2.2, 3.4 and 2.8 respectively.