Determinación de enterovirus en casos con diagnóstico de síndrome de Guillain-Barré mediante la utilización de la técnica de concentración ácida / Determination of enterovirus in cases with a Guillain-Barré syndrome diagnosis using the acid concentration technique

El propósito de este trabajo fue determinar la presencia de enterovirus en materia fecal mediante la utilización de la técnica de concentración ácida (TCA). Para esto se analizaron muestras de 58 niños menores de cinco años con diagnóstico de Síndrome de Guillain-Barré (SGB), tanto por la técnica de rutina como por la técnica propuesta. Se utilizaron como testigos nueve muestras que salieron positivas con la técnica de rutina. En estas nueve muestras y en 22 más (31 casos) se aislaron e identificaron enterovirus tipo no polio mediante la TCA (53 por ciento), por lo tanto, se obtuvo 38 por ciento más de aislamientos utilizando la TCA. El aislamiento celular fue más exitoso en la línea celular RD (59 por ciento) que en la Hep-2c (41 por ciento), aunque los títulos virales que se obtuvieron fueron bajos en su mayoría (71 por ciento). La TCA mejora la detección de enterovirus, sin embargo, por ser más costosa y más laboriosa, únicamente se recomienda su uso en casos de importancia epidemiológica como: los compatibles a polio y cuyo resultado sea negativo al utilizar la técnica de rutina o en casos cuya muestra proviene de un caso de fallecimiento; siempre y cuando las muestras sean tomadas en los primeros 15 días después del inicio de la sintomatología.

Age, renal perfusion and function in island-dwelling indigenous Kuna Amerinds of Panama.

BACKGROUND/AIMS: Among possible contributors to a progressive fall in renal perfusion and function with increasing age, some hypotheses have invoked the rise in blood pressure that occurs with age, and a high-protein diet typical of urban cultures. Kuna Amerinds residing in isolated islands off the Panamanian Coast have a very low protein intake and show no tendency for blood pressure to rise with age, thus providing an opportunity to test these hypotheses. METHODS: We measured renal plasma flow and glomerular filtration rate (PAH and inulin clearance) in 16 Kuna Indians ranging in age from 18 to 86 years (51 +/- 6 years) who have resided on Ailigandi, an isolated Panamanian island for all of their lives. Inulin and PAH were infused with a battery-driven pump for 60 min, and a metabolic clearance rate used to calculate inulin and PAH clearance. For comparison, we employed identical techniques in 29 residents of Boston, ranging in age from 19 to 79 years (52 +/- 4 years), all normotensive and free of disease or medication use. Twenty-four were Caucasian. RESULTS: The Bostonian controls showed the anticipated fall in PAH clearance with age (y = 806 - 4.9 x; r = -0.82; f = 38.0; p < 0.0001). Our hypothesis was that the absence of a blood pressure rise with age and the low protein intake would flatten the slope relating renal perfusion to Kuna age. Our finding was a numerically steeper slope relating age and renal plasma flow in the Kuna (y = 936 - 6.48x; r = -0.81; p < 0.001). Filtration fraction rose with age in both populations, and again the rise was steeper in the Kuna. GFR in the Kuna, on the other hand, was very much higher at any age (139 +/- 4 ml/min/1.73 m2) than in Bostonians (112 +/- 3 ml/min/1.73 m2; p < 0.001). CONCLUSION: The findings are not in accord with the hypothesis that age-related changes in renal perfusion and glomerular filtration rate reflect an important contribution from blood pressure rise and a high protein intake, typical of modern, urban life.

Aging, acculturation, salt intake, and hypertension in the Kuna of Panama.

The indigenous Kuna who live on islands in the Panamanian Caribbean were among the first communities described with little age-related rise in blood pressure or hypertension. Our goals in this study were to ascertain whether isolated island-dwelling Kuna continue to show this pattern, whether migration to Panama City and its environs changed the patterns, and whether the island-dwelling Kuna have maintained their normal blood pressure levels despite partial acculturation, reflected in an increased salt intake. We enrolled 316 Kuna participants who ranged in age from 18 to 82 years. In 50, homogeneity was confirmed by documentation of an O+ blood group. In 92 island dwellers, diastolic hypertension was not identified and blood pressure levels were as low in volunteers over 60 years of age as in those between 20 and 30 years of age. In Panama City, conversely, hypertension prevalence was 10.7% and exceeded 45% in those over 60 years of age (P < .01), blood pressure levels were higher in the elderly, and there was a statistically significant positive relationship between age and blood pressure (P < .01). In Kuna Nega, a Panama City suburb designed to maintain a traditional Kuna lifestyle but with access to the city, all findings were intermediate. Sodium intake and excretion assessed in 50 island-dwelling Kuna averaged 135 +/- 15 mEq/g creatinine per 24 hours, exceeding substantially other communities free of hypertension and an age-related rise in blood pressure. Despite partial acculturation, the island-dwelling Kuna Indians are protected from hypertension and thus provide an attractive population for examining alternative mechanisms.