Magnitudes biológicas que tiene interés medir de modo urgente / Biological markers in emergency laboratory

No disponible

¿Es útil la reevaluación de cristales en el líquido sinovial? / Reassessment of crystals in synovial fluid: is it helpful?

Introducción. El recuento celular, el análisis de cristales y el estudio microbiológico del líquido sinovial (LS), son piezas claves en el diagnóstico y manejo del derrame articular pues conducen a decisiones clínicas y terapéuticas. El análisis de cristales suele realizarse en campo claro y con luz polarizada compensada (LPC). Depende de la experiencia del examinador y del número de cristales presentes. Para aumentar el rendimiento, se puede analizar el sedimento tras centrifugación. Hay autores que sugieren que la maduración in vitro de los cristales facilita su identificación tras 24 horas de la extracción. Otros sugieren que dicha demora deteriora la muestra. Nuestro objetivo es valorar si el re-examen del LS a las 24 horas puede aumentar el rendimiento diagnóstico para cristales. Material y métodos. Se analizaron durante 4 meses las muestras de LS remitidas para su análisis con LP y microscopía de campo claro; se realizó reevaluación a las 24 horas en todos los casos posibles. Resultados. Recibimos 174 LS, de los cuales 138 (79,3%) fueron negativos para el primer análisis y 36 positivos. En 84 casos (60,8%) se pudo realizar una evaluación a las 24 horas. En 10 casos (11,9%) se observaron cristales que no habían sido vistos en el primer análisis. Siempre se trató de cristales de pirofosfato cálcico dihidratado. El incremento de muestras positivas tras el segundo examen fue de un 27,8% (IC 95%: 13,1-42,4). Conclusión. El reanálisis de cristales en LS a las 24 horas debe considerarse en los casos de sospecha de artropatía microcristalina con primer examen negativo (AU)

Background. White blood cell counts, analysis of crystals in synovial fluid (SF) and microbiological studies are key measurements in the diagnosis and management of joint effusion. The results may lead to clinical and therapeutic decisions. The diagnosis of crystals in SF, usually performed by examination with compensated polarised light microscopy (PL), is not easy. It depends on the experience of the examiner and amount of crystals in the sample, which is sometimes very small. In order to increase the performance, analysis may be performed on the sediment after centrifugation. Some authors suggest that due to in vitro maturation of crystals, they can be more easily identified 24hours after extraction. Others suggest that the sample deteriorates. We question whether re-examination of SF can increase the diagnostic yield of this test. Methods. Over a 4 month period we analysed crystals in SF received in the laboratory using a PL and ordinary light microscopy. Where this was possible, the SF was examined again after 24hours. Results. We received 174 SF; 138 (79.3%) were negative for the first analysis. In 84 cases (60.8%) a re-evaluation could be made after 24hours by trained staff. In 10 cases (11.9%) crystals that had not been seen previously became apparent. In all cases they were calcium pyrophosphate dihydrate crystals. The number of positive fluids increased by 27.8% (95% CI: 13.1-42.4) after a second assay. Conclusions. The re-analysis of crystals in SF at 24hours should be considered in cases of high suspicion of microcrystalline arthropathy when the first test is negative (AU)

[Relation between intermediate troponin T values and diagnosis of cardiac disease]. / Relación de los valores intermedios de troponina T con el diagnóstico de enfermedad cardíaca.

BACKGROUND AND OBJECTIVE: Troponins are useful tools in management of patients with acute coronary syndrome (ACS). Small increases do not guarantee a desirable precision (CV < 10%) and there is a "grey zone" between 99 percentile and clinical cut off. Our objective was to evaluate if "grey zone" troponin values reflect heart damage or they are only "analyzer noise". PATIENTS AND METHOD: Final diagnoses of patients with "grey zone" values attended during 2001 and 2002 were reviewed (group Tn). Control group (Cn): patients with negative values (four months randomly chosen during the same period). Admitted patients were classified in: A, ACS; B, non ischemic heart disease, and C, non heart disease. RESULTS: Tn group (n = 521): admitted, 330 (63.3%); A (53.9%), B (30.9%), C (15.2%). Cn group (n = 652): admitted, 156 (23.9%); A (41%), B (24.4%), C (34.6%). Odds ratio for admittance (Tn vs Cn) was 4.82 (95% CI, 3.68-6.31); OR for diagnosis A, B and C (Tn vs Cn) were: A (1.56) (95% CI, 1.04-2.34), B (1.43) (95% CI, 0.90-2.25), C (0.38) (95% CI, 0.24-0.6). CONCLUSIONS: Intermediate troponin values are associated with diagnosis of heart disease, especially ACS.

Relación de los valores intermedios de troponina T con el diagnóstico de enfermedad cardíaca / Relation between intermediate troponin T values and diagnosis of cardiac disease

FUNDAMENTO Y OBJETIVO: Las troponinas son útiles en el diagnóstico del síndrome coronario agudo (SCA). Pequeños incrementos no garantizan la imprecisión recomendable (CV < 10%).Así, existe una «zona gris» de valores intermedios entre el valor superior de la normalidad yel punto de corte de decisión clínica. Evaluamos si estos valores de cTnT reflejan lesión miocárdica o son «ruido» del analizador. PACIENTES Y MÉTODO: Estudiamos a pacientes de urgencias con valores intermedios de cTnT durante 2001-2002 (grupo Tn). Grupo control (Cn): muestra de pacientes del mismo período con cTnT negativa. Grupos diagnósticos finales: A, relacionados con SCA; B, relacionados con patología cardíaca no isquémica; C, enfermedades no cardíacas. RESULTADOS: Grupo Tn (n = 521): ingresos, 330(63,3%); A (53,9%), B (30,9%), C (15,2%).Grupo Cn (n = 652): ingresos, 156 (23,9%); A(41%), B (24,4%), C (34,6%). Odds ratio para ingresos en grupo Tn frente al Cn, 4,82 (IC del95%, 3,68-6,31); para los diagnósticos: A 1,56(IC del 95%, 1,04-2,34), B 1,43 (IC del 95%,0,90-2,25), C 0,38 (IC del 95%, 0,24-0,6).CONCLUSIONES: Los valores intermedios de cTnT se asocian con patología cardíaca, especialmente SCA

BACKGROUND AND OBJECTIVE: Troponins are useful tools in management of patients with acute coronary syndrome (ACS). Small increases do not guarantee a desirable precision (CV < 10%) and there is a «grey zone» between 99 percentile and clinical cut off. Our objective was to evaluate if «grey zone» troponin values reflect heart damage or they are only «analyzer noise». PATIENTS AND METHOD: Final diagnoses of patients with «grey zone» values attended during2001 and 2002 were reviewed (group Tn).Control group (Cn): patients with negative values(four months randomly chosen during the same period). Admitted patients were classifiedin: A, ACS; B, non ischemic heart disease, and C, non heart disease. RESULTS: Tn group (n = 521): admitted, 330(63.3%); A (53.9%), B (30.9%), C (15.2%).Cn group (n = 652): admitted, 156 (23.9%);A (41%), B (24.4%), C (34.6%). Odds ratio for admittance (Tn vs Cn) was 4.82 (95% CI,3.68-6.31); OR for diagnosis A, B and C (Tnvs Cn) were: A (1.56) (95% CI, 1.04-2.34), B(1.43) (95% CI, 0.90-2.25), C (0.38) (95%CI, 0.24-0.6).CONCLUSIONS: Intermediate troponin values are associated with diagnosis of heart disease, especially ACS