Revista Brasileira de Ginecologia e Obstetrícia (Feb 2010)
Rastreamento de cardiopatias congênitas associadas ao diabetes mellitus por meio da concentração plasmática materna de frutosamina Congenital cardiopathies screening associated with diabetes mellitus using maternal fructosamine plasma concentration
Abstract
OBJETIVO: avaliar a importância da concentração plasmática materna de frutosamina como indicador de cardiopatias congênitas fetais, em gestações complicadas pelo diabetes mellitus. MÉTODOS: o estudo retrospectivo incluiu 91 gestantes portadoras de diabetes mellitus, as quais foram submetidas à ecocardiografia fetal de rotina em centro universitário de referência em Medicina Fetal. Foram selecionadas 65 pacientes que apresentavam diabete pré-gestacional e registro em prontuário médico de frutosamina plasmática anterior ao exame ultrassonográfico. A primeira dosagem registrada foi confrontada com o resultado da ecocardiografia fetal de rotina, realizada por médico especialista do serviço. A presença ou ausência de achados ecográficos de cardiopatia congênita (AECC) foi relacionada aos níveis plasmáticos de frutosamina, por meio de teste de médias, e sua acuidade para AECC verificada por curva ROC. Foram discutidos como pontos de corte os valores da concentração plasmática materna de frutosamina de 2,68, 2,9 e 2,23 mmol/L, que são, respectivamente, o valor de referência local do laboratório, o do kit de dosagem empregado e o de maior acurácia global. RESULTADOS: o AECC foi encontrado em 52,3% dos fetos. A primeira dosagem de frutosamina durante o pré-natal aconteceu em média com 20,4±8,0 semanas de gestação. A capacidade da concentração materna de frutosamina em identificar fetos com AECC foi significante (pPURPOSE: to evaluate the importance of maternal plasma concentration of fructosamine as an indicator of fetal congenital cardiopathies in pregnancies complicated by diabetes mellitus. METHODS: this was a retrospective study conducted on 91 pregnant women with diabetes mellitus who underwent routine fetal echocardiography at a university reference center in fetal medicine. Sixty-five patientes who presented pre-gestational diabetes mellitus and plasma fructosamine level were registered in the medical records prior to the ultrasound exam. The first measurement recorded was compared with the result of routine fetal echocardiography, carried out by a specialist physician of the service. The presence or absence of echocardiographic findings of congenital cardiopathies (EFCC) was related to plasma levels of fructosamine by the mean t-test and its accuracy for EFCC was verified by the ROC curve. Plsama fructosamine concentrations of 2.68, 2.9 and 2.23 mmol/L, which are, respectively, the local reference laboratory values, the value of the kit employed for measurement and the one of highest overall accuracy, were discussed as the cut-off values. RESULTS: EFCC was found in 52.3% of the fetuses. The first measurement of fructosamine, during the prenatal care period, was performed, on average, at 20.4±8.0 weeks of pregnancy. The maternal concentration ability of the fructosamine to identify fetuses with EFCC was significant (p<0.0001) and had an area under the ROC curve of 0.78 (95%CI=0.66-0.89). The 2.9 mmol/L plasma concentration of fructosamine revealed EFCC with better specificity, but with a higher percentage of false-negative results (96.8 and 55.9%). Values above 2.68 mmol/L were associated with a probability of 4.6 to identify fetuses with EFCC compared with lower values, with 58.8% of sensitivity and 87.1%, specificity. The value of 2.23 mmol/L proved to be the most overall accurate of the three values suggested, with a sensitivity of 88.2% in the identification of fetuses with echocardiographic abnormalities. CONCLUSIONS: it is possible to use a second trimester plasma fructosamine level to refer high risk pregnant women to a reference center of fetal echocardiography. These findings are important for the management of women with diabetes mellitus who initiate late prenatal care.
Keywords
