[Implementation of nine quality indicators in a hospital emergency clinical laboratory]. / Implementación de 9 indicadores de calidad en un laboratorio hospitalario.

BACKGROUND: Quality indicators are tools used to monitor specific activities within a process and improve it. In the area of clinical laboratories, the National Accreditation Standards for Providers of Health and the ISO 15189 standard recommend the implementation of indicators that monitor the test cycle with emphasis on those that contribute to a safer health care. AIM: To describe the implementation of nine indicators in a hospital clinical laboratory and their measurement during one year. MATERIAL AND METHODS: The indicators implemented and measured were four of the pre-analytical phase (number of rejected samples, times of transport, blood culture contamination and blood cultures inoculated with adequate blood volumes), two of the analytical phase (coherence of Gram stains of blood culture with microorganism cultured and correct results in external quality control surveys) and three of the post-analytical phase (compliance with order to report lapse goals, corrected reports and alert values report). RESULTS: Two indicators of pre-analytical phase did not meet the per determined targets: number of rejected samples and blood cultures inoculated with adequate blood volume. All indicators of the analytical and post analytical phases were within the pre-determined targets. CONCLUSIONS: Coordinated work should be initiated especially with the nursing service to correct the two indicators that did not meet the target. The incorporation of quality indicators to monitor critical processes within the laboratory was undoubtedly an opportunity to identify areas for improvement.

Implementación de 9 indicadores de calidad en un laboratorio hospitalario / Implementation of nine quality indicators in a hospital emergency clinical laboratory

Background: Quality indicators are tools used to monitor specific activities within a process and improve it. In the area of clinical laboratories, the National Accreditation Standards for Providers of Health and the ISO 15189 standard recommend the implementation of indicators that monitor the test cycle with emphasis on those that contribute to a safer health care. Aim: To describe the implementation of nine indicators in a hospital clinical laboratory and their measurement during one year. Material and Methods: The indicators implemented and measured were four of the pre-analytical phase (number of rejected samples, times of transport, blood culture contamination and blood cultures inoculated with adequate blood volumes), two of the analytical phase (coherence of Gram stains of blood culture with microorganism cultured and correct results in external quality control surveys) and three of the post-analytical phase (compliance with order to report lapse goals, corrected reports and alert values report). Results: Two indicators of pre-analytical phase did not meet the per determined targets: number of rejected samples and blood cultures inoculated with adequate blood volume. All indicators of the analytical and post analytical phases were within thepre-determined targets. Conclusions: Coordinated work should be initiated especially with the nursing service to correct the two indicators that did not meet the target. The incorporation of quality indicators to monitor critical processes within the laboratory was undoubtedly an opportunity to identify areas for improvement.

[Troponin in the diagnosis of myocardial infarction: An approach from the Clinical Laboratory]. / Troponina en el diagnóstico de infarto al miocardio: Consideraciones desde el laboratorio clínico.

Among the many biomarkers studied to evaluate myocardial damage, troponin is considered the most sensitive and specific. However, current methodologies present pre-analytical, analytical and post-analytical problems, of which the more significant are the lack of standardization and a high uncertainty in the level of decision or cut-off. It is hoped that a new generation of assays called "ultra sensitive" will improve analytical performance characteristics of the technique and achieve compliance with the internationally recommended quality specifications.

Troponina en el diagnóstico de infarto al miocardio: consideraciones desde el laboratorio clínico / Troponin in the diagnosis of myocardial infarction: an approach from the clinical laboratory

Among the many biomarkers studied to evaluate myocardial damage, troponin is considered the most sensitive and specific. However, current methodologies present pre-analytical, analytical and post-analytical problems, of which the more significant are the lack of standardization and a high uncertainty in the level of decision or cut-off. It is hoped that a new generation of assays called "ultra sensitive" will improve analytical performance characteristics of the technique and achieve compliance with the internationally recommended quality specifications.

Entre los múltiples biomarcadores estudiados para evaluar daño miocárdico, la troponina se considera el más sensible y específico. Sin embargo, la mayoría de las metodologías actuales utilizadas para su determinación presentan problemas tanto pre-analíticos, analíticos como post-analíticos, de los cuales los más relevantes son la falta de estandarización y una imprecisión alta en el nivel de decisión o de corte. Se espera que una nueva generación de ensayos para la determinación de troponina, denominados ultrasensibles, mejoren las características de desempeño de la técnica y logren cumplir con las especificaciones de calidad recomendadas internacionalmente.

[Laboratory alert value reporting by the clinical laboratory at an academic medical network]. / Aviso de valores de alerta por parte del laboratorio clínico en una red de salud universitaria.

BACKGROUND: An alert value is a result suggesting that the patient is at imminent danger unless appropriate remedial actions begin promptly. Report of alert values (AV) by the clinical laboratories has taken special relevance in recent years due to its contribution to patient's care. AIM: To report results of AV informed during 2007 within the Health Network of the Pontificia Universidad Católica de Chile. MATERIAL AND METHODS: Analysis of AV recorded in a centralized database of the laboratories of the health network, between January and December, 2007. RESULTS: Total number of AV was 5.366, which represented 0.3% of total examinations and corresponded mainly to the clinical chemistry area. Potassium levels generated the higher number of AV detected, followed by positive blood cultures. Eighty two percent of AV corresponded to hospitalized patients. The greater number of AV was reported to intermediate and intensive care services. Thirty two percent of AV was informed to the physician or professional in charge of the patient within 5 minutes of obtaining the results and 79% within 30 minutes. CONCLUSIONS: To obtain a real impact on patient management, it is fundamental to shorten the lapse between the obtainment of tests results and the warning, supported on appropriate computerized systems, and to spread the procedure to all personnel involved in patient's care.

[Are blood glucose measurements made with portable glucometers reliable?]. / ¿Podemos confiar en una glicemia realizada en un glucómetro al lado de la cama del enfermo?

Examinations performed beside the bed of patients ("Point-of-care testing, POCT") provide immediate results and are simple to perform. The most common of these tests is the self control of blood glucose levels in diabetic patients. The use of these devices at the hospital level, introduces a new set of requirements to health institutions, which should monitor all aspects of the process, including training of final users, proper quality control, development of written procedures for use and even participation in surveys of external quality control, avoiding the generation of errors and guaranteeing patient safety.

Aviso de valores de alerta por parte del laboratorio clínico en una red de salud universitaria / Laboratory alert value reporting by the clinical laboratory at an academic medical network

Background: An alert value is a result suggesting that the patient is at imminent danger unless appropriate remedial actions begin promptly. Report of alert values (AV) by the clinical laboratories has taken special relevance in recent years due to its contribution to patient's care. Aim: To report results of AV informed during 2007 within the Health Network of the Pontificia Universidad Católica de Chile. Material and methods: Analysis of AV recorded in a centralized database of the laboratories of the health network, between January and December, 2007. Results: Total number of AV was 5.366, which represented 0.3 percent of total examinations and corresponded mainly to the clinical chemistry area. Potassium levels generated the higher number of AV detected, followed by positive blood cultures. Eighty two percent of AV corresponded to hospitalized patients. The greater number of AV was reported to intermediate and intensive care services. Thirty two percent of AV was informed to the physician or professional in charge of the patient within 5 minutes of obtaining the results and 79 percent within 30 minutes. Conclusions: To obtain a real impact on patient management, it is fundamental to shorten the ¡apse between the obtainment of tests results and the warning, supported on appropriate computerized systems, and to spread the procedure to all personnel involved in patient's care (RevMéd Chile 2009; 137: 1137-44).

¿Podemos confiar en una glicemia realizada en un glucómetro al lado de la cama del enfermo? / Are blood glucose measurements made with portable glucometers reliable?

Examinations performed beside the bed of patients ("Point-ofcare testing, POCT") provide immediate results and are simple to perform. The most common of these tests is the self control of blood glucose levels in diabetic patients. The use of these devices at the hospital level, introduces a new set of requirements to health institutions, which should monitor all aspects of the process, including training of final users, proper quality control, development of written procedures for use and even participation in surveys of external quality control, avoiding the generation of errors and guaranting patient safety (Rev Méd Chile 2009; 137:1261-4).

Los exámenes realizados al lado de la cama del enfermo ("Point of care testing, POCT") tienen como mayor ventaja la rapidez en la entrega de resultados y la simplicidad de uso, siendo su principal aplicación el autocontrol de la glicemia en pacientes diabéticos. El uso de estos equipos a nivel hospitalario introduce exigencias a las instituciones de salud, las cuales deben monitorizar todos ¡os aspectos del proceso, incluyendo la capacitación de los usuarios, el adecuado control de calidad, el desarrollo de procedimientos escritos para su uso e inclusive la participación en encuestas de control de calidad externo, evitando la generación de errores y colaborando así con la seguridad del paciente.

Nueva serie sobre Laboratorio Clínico en la Revista Médica de Chile: [editorial] / New series on Clinical Laboratory in Revista Médica de Chile: [editorial]

The Chilean Autonomous Commission for Medical Specialties Certification recognized Clinical Laboratory as a specialty in 1994. This decision was based on the great development of the specialty that incorporated new methodologies and developed automatic computerized methods. The main objective of the Clinical Laboratory specialist is to work as a consultant to define the laboratory diagnostic strategies that have the best cost effectiveness ratio. He must also select and assess diagnostic methods, supervise their implementations and assure the quality of the results generated. He must also be an efficient laboratory director and administrator.

[Diagnosis of congenital syphilis at delivery: maternal serum or cord blood?]. / Pesquisa de sífilis congénita al momento del parto: Suero materno o sangre de cordón?

UNLABELLED: Congenital syphilis (CS) is an important health problem in Chile, with a rate of 0.25/1,000 live newborn (NB) during year 2004. In 2000, the Chilean Ministry of Public Health recommended to perform a screening in cord blood at the moment of delivery. Instead, the Centers for Disease Control and Prevention guidelines recommend the screening in maternal serum since cord blood has up to 5% of false (-) versus 0.5% of maternal serum, both with respect to the NB serum. OBJECTIVE: Maternal serum and NB cord blood were studied during one year to determine the best screening method at delivery. METHODS: RPR was performed and positive results were confirmed by treponemic test (immunochromatographyDetermine, ELISA Captia, Ig and IgM, and MHA-Tp). Serologically confirmed patients were evaluated by the specialist to define CS cases. RESULTS: Between June 1999 and August 2000 2,741 binomies were studied; of these, 37 (1.3%) were RPR reactive and 2.704 were non-reactive. In 11 of the 37 reactive cases, mother and NB were RPR reactive (Group I), in 9 cases the NB was RPR reactive and the mother was non-reactive (Group II), and the other 17 were NB non-reactive and mother reactive (Group III). In group I, 7/11 (64%) were true (+)s and 4/11(36%)) false (+)s of RPR. In group II, 9/9 (100%) corresponded to false (+)s of RPR in cord blood, and in group III, 11/17 (65%) corresponded to false (+)s of RPR in maternal blood but 6/17 (35%) were found to be cases of syphilis during pregnancy. Three of them were not treated opportunely and were designed as CS. In total 9 NB corresponded to CS (6 in group I and 3 in group III). If the screening had been performed only in cord blood, three NB with CS would have not been diagnosed. CONCLUSION: Even when maternal serum has a high rate of false (+)s, it has better sensitivity than cord blood for the diagnosis of CS, thus it is suggested to perform the screening at delivery with maternal serum instead of cord blood samples.

Pesquisa de sífilis congénita al momento del parto: ¿Suero materno o sangre de cordón? / Diagnosis of congenital syphilis at delivery: Maternal serum or cord blood?

La sífilis congénita (SC) es un problema importante en Chile, con una tasa de 0,25/1.000 recién nacidos (RNs) vivos en el año 2004. En el año 2000, el Ministerio de Salud recomendaba como tamizaje al momento del parto una muestra de sangre de cordón. El Centro de Control y Prevención de Enfermedades, (CDC), Atlanta, E.U.A. recomendó, desde 1998, el tamizaje al parto con suero materno ya que respecto del suero del RN, la sangre de cordón y el suero materno tienen respectivamente hasta 5 y 0,5 por ciento> de falsos negativos. Objetivo: Determinar el mejor tamizaje al momento del parto. Métodos: Se estudiaron muestras de suero materno y sangre de cordón de los RNs durante un año. Se realizó RPR y de ser positiva, pruebas treponémicas confirmatorias (imunocromatográfico Determine®, ELISA Captia® IgG e IgM y microhemaglutinación). Todos los pacientes confirmados fueron vistos por el especialista para definir los casos de SC. Resultados: Entre junio de 1999 y agosto del 2000 se estudiaron 2.741 binomios madre-RN; de éstos 37/2.704 (1,3 por ciento) fueron RPR reactivos. Once eran RPR reactivo en la madre y en el RN (Grupo I), 9 eran RPR reactivo en el RN y no reactivo en la madre (Grupo II) y 17 eran RN con RPR no reactivo y reactivo en la madre (Grupo III). En el Grupo I hubo 64 por ciento> (7/11) de verdaderos (+)s y 36 por ciento (4/11) de falsos (+)s del RPR. En el Grupo II, 9/ 9 (100 por cientoo), correspondieron a falsos (+)s del RPR en sangre de cordón y en el Grupo III, 11/17 (67 por ciento>) correspondieron a falsos (+)s del RPR en sangre materna pero hubo 6/17 (35 por ciento>) que correspondían a sífilis durante el embarazo y en tres de ellas no hubo tratamiento intra-embarazo, por lo que fueron catalogadas como SC y los RNs debieron ser tratados. En total hubo 9 RNs que correspondieron a SC (6 del grupo I y 3 del grupo III). Si sólo se hubiese realizado tamizaje en sangre de cordón, 3 RNs con SC no se hubiesen....

Congenital syphilis (CS) is an important health problem in Chile, with a rate of 0.25/1,000 live newborn (NB) during year 2004. In 2000, the Chilean Ministry of Public Health recommended to perform a screening in cord blood at the moment of delivery. Instead, the Centers for Disease Control and Prevention guidelines recommend the screening in maternal serum since cord blood has up to 5 percent of false (-) versus 0.5 percent of maternal serum, both with respect to the NB serum. Objective: Maternal serum and NB cord blood were studied during one year to determine the best screening method at delivery. Methods: RPR was performed and positive results were confirmed by treponemic test (immunochromatographyDetermine®, ELISA Captia®, Ig and IgM, and MHA-Tp). Serologically confirmed patients were evaluated by the specialist to define CS cases. Results: Between June 1999 and August 2000 2,741 binomies were studied; of these, 37 (1.3 percent) were RPR reactive and 2.704 were non-reactive. In 11 of the 37 reactive cases, mother and NB were RPR reactive (Group I), in 9 cases the NB was RPR reactive and the mother was non-reactive (Group II), and the other 17 were NB non-reactive and mother reactive (Group III). In group I, 7/11 (64 percent) were true (+)s and 4/11(36 percent)) false (+)s of RPR. In group II, 9/9 (100 percent) corresponded to false (+)s of RPR in cord blood, and in group III, 11/17 (65 percent) corresponded to false (+)s of RPR in maternal blood but 6/17 (35 percent) were found to be cases of syphilis during pregnancy. Three of them were not treated opportunely and were designed as CS. In total 9 NB corresponded to CS (6 in group I and 3 in group III). If the screening had been performed only in cord blood, three NB with CS would have not been diagnosed. Conclusion: Even when maternal serum has a high rate of false (+)s, it has better sensitivity than cord blood for the diagnosis of CS, thus it is suggested to perform the screening ...

Biomarcadores coronarios y evolución clínica alejada en pacientes con síndromes coronarios agudos sin elevación del segmento ST / Coronary biomarkers and long-term clinical outcome in acute coronary syndrome without ST segment elevation

Background: The use of new biomarkers improved risk stratification for patients with acute coronary syndromes (ACS). Aim: To evaluate the relationship between multiple biomarkers and long-term clinical outcome in ACS without ST segment elevation. Patients and Methods: Consecutive patients presenting with suspected ACS were studied. On admission to the emergency room, serum was obtained to determine highly sensitive C reactive protein (hsCRP), erythrocyte sedimentation rate (ESR), lipoprotein (a) (LPa) and soluble P selectin (sPS). Clinical endpoints were mortality and a composite endpoint of major adverse cardiovascular events (MACE) including death, re-infarction, and angina. Results: Seventy patients, aged 63±13 years, 54 males, were studied. Final diagnosis was unstable angina in 71% and non-ST-segment elevation myocardial infarction in 29%. MACE and mortality rate were 17% and 5.8%, respectively. We found higher plasma levels of hsCRP, ESR and Lp(a) in patients with MACE (p=0.032, p=0.015 and p=0.010, respectively). Plasma levels of hsCRP and ESR were also higher in patients who died during the follow up (p=0.002 y p=0.045, respectively). Conclusion: Plasma levels of inflammatory markers and atherosclerosis biomarkers are associated with a worse long-term clinical outcome in ACS without ST segment elevation. The inclusion of these biomarkers in the routine blood test on admission, could improve risk stratification of patients with ACS in the future.

[Coronary biomarkers and long-term clinical outcome in acute coronary syndrome without ST segment elevation]. / Biomarcadores coronarios y evolución clínica alejada en pacientes con síndromes coronarios agudos sin elevación del segmento ST.

BACKGROUND: The use of new biomarkers improved risk stratification for patients with acute coronary syndromes (ACS). AIM: To evaluate the relationship between multiple biomarkers and long-term clinical outcome in ACS without ST segment elevation. PATIENTS AND METHODS: Consecutive patients presenting with suspected ACS were studied. On admission to the emergency room, serum was obtained to determine highly sensitive C reactive protein (hsCRP), erythrocyte sedimentation rate (ESR), lipoprotein (a) (LPa) and soluble P selectin (sPS). Clinical endpoints were mortality and a composite endpoint of major adverse cardiovascular events (MACE) including death, re-infarction, and angina. RESULTS: Seventy patients, aged 63+/-13 years, 54 males, were studied. Final diagnosis was unstable angina in 71% and non-ST-segment elevation myocardial infarction in 29%. MACE and mortality rate were 17% and 5.8%, respectively. We found higher plasma levels of hsCRP, ESR and Lp(a) in patients with MACE (p=0.032, p=0.015 and p=0.010, respectively). Plasma levels of hsCRP and ESR were also higher in patients who died during the follow up (p=0.002 y p=0.045, respectively). CONCLUSION: Plasma levels of inflammatory markers and atherosclerosis biomarkers are associated with a worse long-term clinical outcome in ACS without ST segment elevation. The inclusion of these biomarkers in the routine blood test on admission, could improve risk stratification of patients with ACS in the future.

Inmunogenicidad de una vacuna recombinante anti hepatitis B en personal de salud / Immune response to hepatitis B vaccine in health care workers

El virus de hepatitis B (HB) es capaz de persistir en un porcentaje de los infectados produciendo enfermedad hepática crónica a largo plazo. El personal de salud es un grupo especialmente expuesto a contraer esta infección. Actualmente se dispone de vacunas HB inmunogénicas, eficaces y seguras. Aunque la mayoría de las personas responde de una forma adecuada, un porcentaje bajo no son respondedores. Con el objeto de evaluar la respuesta inmune a una vacuna recombinante e identificar potenciales factores de riesgo de una respuesta inadecuada, se realizó un estudio prospectivo en funcionarios de la salud. A los 6 meses de recibir 3 dosis de vacuna contra HB (0-1-6 meses) se les midió título de anticuerpos contra antígeno de superficie de hepatitis B (anti HBs). Se estudiaron 485 sujetos con una relación mujer: hombre de 2.6:1 y una edad promedio de 35.8 años. De los 485, 409 (84.3 por ciento) funcionarios presentaron niveles mayores de 100 mUI/ml, 55 (11.3 por ciento) mostraron niveles entre 10 y 100 mUI/ml y 21 (4.3 por ciento) bajo 10 mUI/ml (4.3 por ciento). Un análisis multivariado de estos 3 grupos mostró que a mayor edad, los niveles de anti HBs eran menores (p< 0.01). No se encontró esta asociación con sexo e índice de masa corporal. Estos resultados muestran una adecuada inmunogenicidad de la vacuna recombinante ya que 95.7 por ciento de los individuos vacunados presentó niveles anti HBs considerados como protectores (> 10 mUI/ml)

Utilidad de la citocentrifugación en el diagnóstico bacteriológico microscópico de fluidos corporales / Utility of cytocentrifugation in the microscopic bacterial diagnosis of body fluids

El diagnóstico rápido de microorganismos presentes en fluidos corporales estériles es de gran importancia clínica. La tinción de Gram constituyela principal herramienta para el diagnóstico de estas infecciones, pero la sensibilidad de está técnica varía segín el tipó de muestray la carga bacteriana presente en ella. La concentración de la muestra previa a la tinción, mejora el rendimiento pero requiere volúmenes significativos de la muestra. La citocentrifugación resulta útilya que requiere de escaso volumen de muestra y permite obtener preparaciones uniformemente concentradas. Con el objetivo de evaluar la cito centrifugación en el diagnóstico de fluidos corporales, se estudiaron 52 muestras de fluidos de cavidades estériles recividas en el Laboratorio de Urgencia del Servicio de Laboratorios Clínicos de la Red de Salud UC. Las muestras fueron separadas para centrifugación convencional (CC) a 3000 rpm por 5 minutos (centrifuga Jouan CR3i r) y para citocentrifugación (CT) a 2000 rpm por 10 minutos (Citocentrifuga Cytospin Shandon Inc r). Del sedimento obtenido por CC se realizó un frotis para tición de Gram y cultivo. De la CT se obtuvo una mono capa celular concentrada en un área de 6 mm de diámetro para tinción de Gram. Ambos frotis fueron leídos por el mismo observador. De las 52 muestras analizadas, 18 fueron sugerentes de infección clínica. La sensibilidad para CT v CC fue de 89 por ciento y 61 por ciento, respectivamente. La especificidad fue de 100 por ciento para ambas técnicas. En una evaluación cuantitativa de la celularidad de las muestras, se observó un aumento de los leucocitos en la CT con respecto a CC. Estos resultados muestran que la CT puede ser de gran ayuda en el diagnóstico rápido de las infecciones de fluidos corporales con baja carga bacteriana. Presenta una mayor sensibilidad y facilita la visualización de bacterias, especialmente en muestras con bajo recuento celular

Transferrina carbohidrato deficiente, gammaglutamil transferasa y volumen corpuscular medio en la evaluación de la ingesta alcohólica reciente de bebedores excesivos / Carbohydrate deficient transferrin for the assessment of recent alcohol intake in excessive drinkers

Background: There are no reliable markers to detect heavy drinking or as a tool to control abstinence compliance in alcoholic treatments. The Mean Corpuscular Volume (MCV), and the gammaglutamyl transpeptidase (GGT), are widely used although their predictive value is somewhat limited due to their low specificity. On the other hand, the Carbohydrate-deficient transferrin (CDT) described in the eighties is highly specific and would be of value in early detection of problem drinking. Aim: To compare the sensitivity and specificity of CDT, GGT, and MCV in order to evaluate their single and combined use as markers for detection of heavy drinking behaviour. Patients and Methods : CDT, GGT, and MCV values were determined in blood samples from (a) alcoholics (drinking more than 100 9 alcohol/day; n=47) and (b) healthy volunteers, teetotalers from the Church of Saints of Later Days (n=34). At the time of sampling alcoholics were presently drinking or had been abstinents for no more than six weeks. ROC curves were used to determine the best cut-off point for each marker. Results: Sensitivity was found to be similar for all three markers. Specificity was found higher for GGT (90.9 percent) and CDT (91.0 percent). The combined use of MCV, GGT and CDT, that is, when at least one of the markers is altered, was shown to detect 83 percent of the patients. No correlation was observed between the markers and the level of alcohol intake. Conclusions: CDT could be of value as a marker to detect heavy drinking when used with GGT and MCV values combined. CDT is particularly higher in drinking alcoholics and remains significantly high for at least six weeks after they stop drinking

Evaluación de métodos diagnósticos para sífilis congénita / Evaluation of diagnostic methods for congenital syphilis

La sífilis congénita es un problema relevante en nuestro país. Actualmente no existen exámenes de uso rutinario que permitan confirmar su diagnóstico. En este estudio prospectivo multicéntrico se evaluaron 60 binomios madre-RN que presentaban test no treponémicos (TNT) reactivos. En todas las muestras se realizaron 2 TNT (VDRL y RPR) y 7 test treponémicos (TT): dos evaluaban IgM, uno IgG y cuatro IgM + IgG. La concordancia entre los tests que evaluaban IgG o IgG + IgM fue de 90 por ciento y entre los que evaluaban IgM fue de 87,5 por ciento. Un resultado IgG positivo se observó en 100 por ciento de los binomios cuyas madres presentaron sífilis durante el embarazo o portaban serología residual. La IgM fue positiva en 64 por ciento de las madres con sífilis adecuadamente tratada durante el embarazo, siendo sus neonatos todos IgM negativa. Aquellas madres con un tratamiento inadecuado tuvieron IgM positiva en 82.3 por ciento y sus RN tuvieron IgM positivas en 11,8 por ciento. En conclusión, la IgM materna no aporta al diagnóstico de sífilis congénita, pues su positividad no se correlaciona con el riesgo de que el RN presente este cuadro. La Igm en el RN es útil para el diagnóstico precoz de sífilis congénita, pero su ausencia no descarta esta patología

Diarrea asociada a clostridium difficile: evaluación de varios métodos de diagnóstico / Diarrhea associated to clostridium difficile: evaluation of several diagnostic methods

Clostridium difficile es el principal patógeno asociado a diarrea por uso de antibióticos y/o colitis psedomembranosa en pacientes hospitalizados. El diagnóstico se basa en la sospecha clínica y presencia de un test de laboratorio positivo para la detección de toxina de C. difficile, considerándose como confirmatorio el test de citotoxicidad. Recientemente se han introducido varios inmunoensayos que permiten el diagnóstico rápido; sin embargo, presentan sencibilidad y especificidad variables por lo que requiere ser evaluados por el método de referencia. El objetivo de este trabajo fue evaluar la correlación entre cinco inmunoensayos y el test confirmatorio de citotoxicidad. Para esto se estudiaron las muestras de deposiciones de 60 pacientes hospitalizados con sospecha clínica de diarrea por C. difficile mediante 4 inmunoensayos: 3 ELISA (ToxA Meridian©, Tox A Becton Dickinson© y Tox A + B TechLab© y 1 ensayo inmunocromatográfico tipo tarjeta: Inmunocard Tox A Meridian©. Cuarenta y seis muestras de las 60 se evaluaron por un test tipo tarjeta de reciente introducción: C. difficile ToxA Oxoid©. Como test confirmatorio se consideró el test de citotoxicidad. La sencibilidad fueron respectivamente: para ToxA Meridian© 95,7 y 78.8 por ciento, Tox A Becton Dickinson© 100 y 94,4 por ciento, Tox A + B TechLab© 91.3 y 86,5 por ciento. Inmunocard Tox A Meridian© 87 y 94,6 por ciento y C. difficile ToxA Oxoid© 94,7 y 96,3 por ciento. De acuerdo a los resultados, los test más recomendables serían Tox A Becton Dickinson© y C. difficile ToxA Oxoid©. Según el equipamiento y requerimientos de tiempos de respuestas de cada laboratorio, se debe establecer el tipo de inmunoensayo a utilizar

Comparación entre dos métodos de determinación del test del sudor en el diagnóstico de la fibrosis quística / Comparison of 2 methods of determining the sweat test in the diagnosis of cystic fibrosis

El diagnóstico de fibrosis (FQ) ha sido documentado tradicionalmente por el método de iontoforesis de pilocarpina cuantitiva. Se ha invocado recientemente que un nuevo sistema de recolección y análisis del sudor es fácil de realizar y que daría resultados muy similares al método tradicional. Nuestro objetivo fue evaluar el sistema de recolección macroduct© y análisis del sudor a través del método de conductividad (c) comparándolo con el método de referencia de fotometría de llama (FL) .Se estudiaron 74 niños enviados a estudios al laboratorio,60 en que se descarto FQ (sanos) con edad de 2,7 ñ 3,2 años(x ñ DE), y 14 con FQ previamente diagnosticada, con edad 6,1 ñ 6,3 años en quienes se obtuvo con el sistema Macroduc169© que consiste en la estimulación cutánea con iontoferesis de pilocarpina con recolección directa del sudor en un dispositivo plástico que lo recoge en un capilar flexible dispuesto en espiral. Las muestras se analizaron con método de C y de FL que estima las concentraciones de sodio (Na) y potasio (K) derivadas de la medición de la intensidad de la longitud de onda especifica de cada ion. En los niños sanos, el valor de C fue de 28, ñ 7,9 (rango: 19-55 mmol/l y el de FL de 27,4 ñ 10,1 (p=ns; r=0,98, p < 0,001). En los pacientes con FQ la C fue de 113,4 ñ 9,4 mmol/l (98-128 mmol/l) y por FL de 116,3 ñ 12,8 mmol/l (92-139); (p= ns; r= 0,98; p < 0,001). Utilizando Macroduct© no hubo pacientes con FQ con C menor de 98 mmol/l, en cambio en los normales la C mayor fue 55 mmol/l. Los resultados confirman que el sistema de recolección Macroprod© y análisis del sudor por conductividad es un método simple, confiable y rápido de realizar, lo que puede ser de gran utilidad para mejorar el diagnostico de fibrosis quistica en el país