Comparison of Two Rapid Strip Tests Based on IGFBP-1 and PAMG-1 for the Detection of Amniotic Fluid

Abstract

Our objective was to compare two rapid strip tests for the detection of amniotic fluid, based on the detection of insulin-like growth factor-binding protein-1 (IGFBP-1) and of placental alpha-microglobulin-1 (PAMG-1). Samples of amniotic fluid were taken in 20 pregnant women between 31 3/7 and 41 2/7 gestational weeks at elective cesarean section before delivery of the newborn. These samples were diluted with 0.9% saline solution in a dilution series down to concentrations of 1:320. Immunoassay strip tests were then compared in their ability to detect remaining concentrations of amniotic fluid. In 5 cases, both test methods showed the same results. In all remaining 15 cases, the test based on PAMG-1 proved to be superior by detecting amniotic fluid at least at one descending concentration below the test based on IGFBP-1. Thus, the rapid strip test based on PAMG-1 seems to be a more sensitive bedside test compared with the test based on IGFBP-1 for the detection of amniotic fluid.

Placental alpha microglobulin-1 (AmniSure® test) for detection of premature rupture of fetal membranes

“…Similar to the results of this study, Tagore et al and Chen et al concluded that PAMG-1 was the most accurate method to diagnose rupture of fetal membranes and it had the highest sensitivity, specificity, PPVs and NPVs than the other methods like IGFBP-1 [23,24]. Also, El-Messidi and Cameron [25] concluded that PAMG-1 is a novel technique which provides a future solution to diagnose PROM.…”

The diagnosis of rupture of fetal membranes (ROM): a meta-analysis

“…As Figure 4 shows, the PAMG-1 test performed better than the IGFBP-1 test in the equivocal group across sensitivity and specificity measures (sensitivity, 96.0 % vs. 73.9 % ; specificity, 98.9 % vs. 77.8 % ; PAMG-1 and IGFBP-1 tests, respectively) and also in the diagnostic odds ratio (P = 0.019). In vitro studies attempting to simulate the clinically relevant patient cases in which membrane rupture is not obvious have demonstrated that the PAMG-1 test will remain positive for several serial dilutions of amniotic fluid beyond the level at which the IGFBP-1 test first reads negative [7,39] . The disparate in vivo sensitivities of the two tests found in the present study in patients for whom membrane rupture is suspected, but not obvious, agree with the findings of the in vitro simulations of this same patient group.…”

“…The search yielded 36 articles, eight of which related specifically to the PAMG-1 test [5, 8, 29 -31, 36, 37, 43] , 24 to the IGFBP-1 test [1, 6, 9, 11, 14, 16, 18, 19, 21, 23, 24, 26 -28, 32 -34, 38, 40, 42, 46, 47, 49, 50] , and seven that were related to both [2,7,13,25,39,44,45] . The supplementary search of proceedings of perinatal meetings yielded three abstracts, all of which related specifically to the PAMG-1 test [31,36,43] .…”

Analyse comparative de deux tests diagnostiques de rupture prématurée des membranes dans les sécrétions cervico-vaginales

“…Si l'examinateur n'a pas anticipé la réalisation du test, un second examen sous spéculum sera imposé à la patiente.Le test AmniSure ® dont le principe est comparable à celui d'Actim TM Prom permet de détecter la protéine PAMG-1. Des données in vitro, sur des dilutions de liquide amniotique, montrent que comparativement au test Actim TM Prom, le test AmniSure ® reste positif à des dilutions plus importantes[19]. Au cours d'une étude clinique répertoriant une série de 203 patientes, Cousin et al trouvaient pour ce test une sensibilité de 98,9 %, une spécificité de 100 %, une valeur prédictive positive de 100 % et une valeur prédic-tive négative de 99,1 %…”