Intracervical lakes as sonographic marker of placenta accreta spectrum disorder in patients with placenta previa or low-lying placenta.

OBJECTIVE: To evaluate the diagnostic accuracy of a new ultrasound sign, intracervical lakes (ICL), in predicting the presence of placenta accreta spectrum (PAS) disorder and delivery outcome in patients with placenta previa or low-lying placenta. METHODS: This was a retrospective multicenter study of women with placenta previa or low-lying placenta at ≥ 26 weeks' gestation, who were referred to three Italian tertiary units from January 2015 to September 2018. The presence of ICL, defined as tortuous anechoic spaces within the cervix which appeared to be hypervascular on color Doppler, was evaluated on ultrasound images obtained at the time of referral. The primary aim was to explore the diagnostic accuracy of ICL in detecting the presence and depth of PAS disorder. The secondary aim was to explore the accuracy of this sign in predicting total estimated blood loss, antepartum bleeding, major postpartum hemorrhage at the time of Cesarean section and need for Cesarean hysterectomy. The diagnostic accuracy of ICL in combination with typical sonographic signs of PAS disorder, was assessed by computing summary estimates of sensitivity, specificity, positive and negative predictive values, positive and negative likelihood ratios and diagnostic odds ratios (DOR). RESULTS: A total of 332 women with placenta previa or low-lying placenta were included in the analysis, with a median maternal age of 33.0 (interquartile range, 29.0-37.0) years. ICL were noted in 15.1% of patients. On logistic regression analysis, the presence of ICL was associated independently with major postpartum hemorrhage (odds ratio (OR), 3.3 (95% CI, 1.6-6.5); P < 0.001), Cesarean hysterectomy (OR, 7.0 (95% CI, 2.1-23.9); P < 0.001) and placenta percreta (OR, 2.8 (95% CI, 1.3-5.8); P ≤ 0.01), but not with the presence of any PAS disorder (OR, 1.6 (95% CI, 0.7-3.5); P = 0.2). Compared with the group of patients without ultrasound signs of PAS disorder, the presence of at least one typical sonographic sign of PAS disorder in combination with ICL had a DOR of 217.2 (95% CI, 27.7-1703.4; P < 0.001) for placenta percreta and of 687.4 (95% CI, 121.4-3893.0; P < 0.001) for Cesarean hysterectomy. CONCLUSION: ICL may represent a marker of deep villus invasion in women with suspected PAS disorder on antenatal sonography and anticipate the occurrence of severe maternal morbidity. Copyright © 2019 ISUOG. Published by John Wiley & Sons Ltd.

Los espacios intracervicales como marcador ecográfico de trastornos del espectro de la placenta acreta en pacientes con placenta previa o placenta baja OBJETIVO: Evaluar la precisión del diagnóstico de un nuevo indicio de ultrasonido, los espacios intracervicales (EIC), para predecir la presencia de trastornos del espectro de la placenta acreta (EPA) y el resultado del parto en pacientes con placenta previa o placenta baja. MÉTODOS: Este fue un estudio multicéntrico retrospectivo de mujeres con placenta previa o placenta baja a ≥ 26 semanas de gestación, que se remitieron a tres unidades terciarias italianas desde enero de 2015 a septiembre de 2018. Se evaluó la presencia de EIC, definida como espacios anecoicos tortuosos dentro del cuello uterino que parecían ser hipervasculares en el Doppler a color, en imágenes de ecografías obtenidas en el momento de la remisión. El objetivo principal fue estudiar la precisión del diagnóstico mediante EIC en la detección de la presencia y la profundidad de un trastorno del EPA. El objetivo secundario fue explorar la precisión de este indicador para predecir la pérdida total estimada de sangre, la hemorragia antes del parto, la hemorragia puerperal importante en el momento de la cesárea y la necesidad de una histerectomía por cesárea. La precisión diagnóstica de EIC, en combinación con los indicios ecográficos típicos de los trastornos del EPA, se evaluó calculando estimaciones estadísticas descriptivas de la sensibilidad, la especificidad, los valores predictivos positivos y negativos, los cocientes de verosimilitud positivos y negativos y las razones de momios del diagnóstico (RMD). RESULTADOS: En el análisis se incluyó un total de 332 mujeres con placenta previa o placenta baja, con una mediana de la edad materna de 33,0 años (rango intercuartil, 29,0-37,0). Se observaron EIC en el 15,1% de las pacientes. En el análisis de regresión logística, la presencia de EIC se asoció de forma independiente con la hemorragia puerperal grave (razón de momios (RM), 3,3 (IC 95%, 1,6-6,5); P<0,001), la histerectomía por cesárea (RM, 7,0 (IC 95%, 2,1-23,9); P<0,001) y la placenta percreta (RM, 2,8 (IC 95%, 1,3-5,8); P≤0,01), pero no con la presencia de ningún trastorno del EPA (RM, 1,6 (IC 95%, 0,7-3,5); P=0,2). En comparación con el grupo de pacientes sin indicios de ultrasonido de algún trastorno del EPA, la presencia de al menos un indicio ecográfico típico de trastorno del EPA en combinación con EIC tuvo una RMD de 217,2 (IC 95%, 27,7-1703,4; P<0,001) para la placenta percreta y de 687,4 (IC 95%, 121,4-3893,0; P<0,001) para la histerectomía por cesárea. CONCLUSIÓN: Los EIC pueden representar un marcador de invasión profunda de las vellosidades en mujeres con sospecha de algún trastorno del EPA basado en la ecografía prenatal y anticipar la presencia de una morbilidad materna grave.

Value of first-trimester ultrasound in prediction of third-trimester sonographic stage of placenta accreta spectrum disorder and surgical outcome.

OBJECTIVES: To explore whether early first-trimester ultrasound can predict the third-trimester sonographic stage of placenta accreta spectrum (PAS) disorder and to elucidate whether combining first-trimester ultrasound findings with the sonographic stage of PAS disorder can stratify the risk of adverse surgical outcome in women at risk for PAS disorder. METHODS: This was a retrospective analysis of prospectively collected data from women with placenta previa, and at least one previous Cesarean delivery (CD) or uterine surgery, for whom early first-trimester (5-7 weeks' gestation) ultrasound images could be retrieved. The relationship between the position of the gestational sac and the prior CD scar was assessed using three sonographic markers for first-trimester assessment of Cesarean scar (CS) pregnancy, reported by Calí et al. (crossover sign (COS)), Kaelin Agten et al. (implantation of the gestational sac on the scar vs in the niche of the CS) and Timor-Tritsch et al. (position of the center of the gestational sac below vs above the midline of the uterus), by two different examiners blinded to the final diagnosis and clinical outcome. The primary aim of the study was to explore the association between first-trimester ultrasound findings and the stage of PAS disorder on third-trimester ultrasound. Our secondary aim was to elucidate whether the combination of first-trimester ultrasound findings and sonographic stage of PAS disorder can predict surgical outcome. Logistic regression analysis and area under the receiver-operating-characteristics curve (AUC) were used to analyze the data. RESULTS: One hundred and eighty-seven women with vasa previa were included. In this cohort, 79.6% (95% CI, 67.1-88.2%) of women classified as COS-1, 94.4% (95% CI, 84.9-98.1%) of those with gestational-sac implantation in the niche of the prior CS and 100% (95% CI, 93.4-100%) of those with gestational sac located below the uterine midline, on first-trimester ultrasound, were affected by the severest form of PAS disorder (PAS3) on third-trimester ultrasound. On multivariate logistic regression analysis, COS-1 (odds ratio (OR), 7.9 (95% CI, 4.0-15.5); P < 0.001), implantation of the gestational sac in the niche (OR, 29.1 (95% CI, 8.1-104); P < 0.001) and location of the gestational sac below the midline of the uterus (OR, 38.1 (95% CI, 12.0-121); P < 0.001) were associated independently with PAS3, whereas parity (P = 0.4) and the number of prior CDs (P = 0.5) were not. When translating these figures into diagnostic models, first-trimester diagnosis of COS-1 (AUC, 0.94 (95% CI, 0.91-0.97)), pregnancy implantation in the niche (AUC, 0.92 (95% CI, 0.89-0.96)) and gestational sac below the uterine midline (AUC, 0.92 (95% CI, 0.88-0.96)) had a high predictive accuracy for PAS3. There was an adverse surgical outcome in 22/187 pregnancies and it was more common in women with, compared to those without, COS-1 (P < 0.001), gestational-sac implantation in the niche (P < 0.001) and gestational-sac position below the uterine midline (P < 0.001). On multivariate logistic regression analysis, third-trimester ultrasound diagnosis of PAS3 (OR, 4.3 (95% CI, 2.1-17.3)) and first-trimester diagnosis of COS-1 (OR, 7.9 (95% CI, 4.0-15.5); P < 0.001), pregnancy implantation in the niche (OR, 29.1 (95% CI, 8.1-79.0); P < 0.001) and position of the sac below the uterine midline (OR, 6.6 (95% CI, 3.9-16.2); P < 0.001) were associated independently with adverse surgical outcome. When combining the sonographic coordinates of the three first-trimester imaging markers, we identified an area we call high-risk-for-PAS triangle, which may enable an easy visual perception and application of the three methods to prognosticate the risk for CS pregnancy and PAS disorder, although it requires validation in large prospective studies. CONCLUSIONS: Early first-trimester sonographic assessment of pregnancies with previous CD can predict reliably ultrasound stage of PAS disorder. Combination of findings on first-trimester ultrasound with second- and third-trimester ultrasound examination can stratify the surgical risk in women affected by a PAS disorder. Copyright © 2019 ISUOG. Published by John Wiley & Sons Ltd.

Interobserver agreement in MRI assessment of severity of placenta accreta spectrum disorders.

OBJECTIVE: To evaluate the level of agreement in the prenatal magnetic resonance imaging (MRI) assessment of the presence and severity of placenta accreta spectrum (PAS) disorders between examiners with expertise in the diagnosis and management of these conditions. METHODS: This was a secondary analysis of a prospective study including women with placenta previa or low-lying placenta and at least one prior Cesarean delivery or uterine surgery, who underwent MRI assessment at a regional referral center for PAS disorders in Italy, between 2007 and 2017. The MRI scans were retrieved from the hospital electronic database and assessed by four examiners, who are considered to be experts in the diagnosis and surgical management of PAS disorders. The examiners were blinded to the ultrasound diagnosis, histopathological findings and clinical data of the patients. Each examiner was asked to assess 20 features on the MRI scans, including the presence, depth and topography of placental invasion. Depth of invasion was defined as the degree of adhesion and invasion of the placenta into the myometrium and uterine serosa (placenta accreta, increta or percreta) and the histopathological examination of the removed uterus was considered the reference standard. Topography of the placental invasion was defined as the site of placental invasion within the uterus in relation to the posterior bladder wall (posterior upper bladder wall and uterine body, posterior lower bladder wall and lower uterine segment and cervix or no visible bladder invasion) and the site of invasion at surgery was considered the reference standard. The degree of interrater agreement (IRA) was evaluated by calculating both the percentage of observed agreement among raters and the Fleiss kappa (κ) value. RESULTS: Forty-six women were included in the study. The median gestational age at MRI was 33.8 (interquartile range, 33.1-34.0) weeks. A final diagnosis of placenta accreta, increta and percreta was made in 15.2%, 17.4% and 50.0% patients, respectively. There was excellent agreement between the four examiners in the assessment of the overall presence of a PAS disorder (IRA, 92.1% (95% CI, 86.8-94.0%); κ, 0.90 (95% CI, 0.89-1.00)). However, there was significant heterogeneity in IRA when assessing the different MRI signs suggestive of a PAS disorder. There was excellent agreement between the examiners in the identification of the depth of placental invasion on MRI (IRA, 98.9% (95% CI, 96.8-100.0%); κ, 0.95 (95% CI, 0.89-1.00)). However, agreement in assessing the topography of placental invasion was only moderate (IRA, 72.8% (95% CI, 72.7-72.9%); κ, 0.56 (95% CI, 0.54-0.66)). More importantly, when assessing parametrial invasion, which is one of the most significant prognostic factors in women affected by PAS, the agreement was substantial and moderate in judging the presence of invasion in the coronal (IRA, 86.6% (95% CI, 86.5-86.7%); κ, 0.69 (95% CI, 0.59-0.71)) and axial (IRA, 78.6% (95% CI, 78.5-78.7%); κ, 0.56 (95% CI, 0.33-0.60)) planes, respectively. Likewise, interobserver agreement in judging the presence and the number of newly formed vessels in the parametrial tissue was moderate (IRA, 88.0% (95% CI, 88.0-88.1%); κ, 0.59 (95% CI, 0.45-0.68)) and fair (IRA, 66.7% (95% CI, 66.6-66.7%); κ, 0.22 (95% CI, 0.12-0.37)), respectively. CONCLUSIONS: MRI has excellent interobserver agreement in detecting the presence and depth of placental invasion, while agreement between the examiners is lower when assessing the topography of invasion. The findings of this study highlight the need for a standardized MRI staging system for PAS disorders, in order to facilitate objective correlation between prenatal imaging, pregnancy outcome and surgical management of these patients. Copyright © 2019 ISUOG. Published by John Wiley & Sons Ltd.

Prenatal ultrasound staging system for placenta accreta spectrum disorders.

OBJECTIVES: To develop a prenatal ultrasound staging system for placenta accreta spectrum (PAS) disorders in women with placenta previa and to evaluate its association with surgical outcome, placental invasion and the clinical staging system for PAS disorders proposed by the International Federation of Gynecology and Obstetrics (FIGO). METHODS: This was a secondary retrospective analysis of prospectively collected data from women with placenta previa. We classified women according to the following staging system for PAS disorders, based upon the presence of ultrasound signs of PAS in women with placenta previa: PAS0, placenta previa with no ultrasound signs of invasion or with placental lacunae but no evidence of abnormal uterus-bladder interface; PAS1, presence of at least two of placental lacunae, loss of the clear zone or bladder wall interruption; PAS2, PAS1 plus uterovescical hypervascularity; PAS3, PAS1 or PAS2 plus evidence of increased vascularity in the inferior part of the lower uterine segment potentially extending into the parametrial region. We explored whether this ultrasound staging system correlates with surgical outcome (estimated blood loss (EBL, mL), units of packed red blood cells (PRBC), fresh frozen plasma (FFP) and platelets (PLT) transfused, operation time (min), surgical complications defined as the occurrence of any damage to the bladder, ureters or bowel, length of hospital stay (days) and admission to intensive care unit (ICU)) and depth of placental invasion. The correlation between the present ultrasound staging system and the clinical grading system proposed by FIGO was assessed. Prenatal and surgical management were not based on the proposed prenatal ultrasound staging system. Linear and multiple regression models were used. RESULTS: Two-hundred and fifty-nine women were included in the analysis. Mean EBL was 516 ± 151 mL in women with PAS0, 609 ± 146 mL in those with PAS1, 950 ± 190 mL in those with PAS2 and 1323 ± 533 mL in those with PAS3, and increased significantly with increasing severity of PAS ultrasound stage. Mean units of PRBC transfused were 0.05 ± 0.21 in PAS0, 0.10 ± 0.45 in PAS1, 1.19 ± 1.11 in PAS2 and 4.48 ± 2.06 in PAS3, and increased significantly with PAS stage. Similarly, there was a progressive increase in the mean units of FFP transfused from PAS1 to PAS3 (0.0 ± 0.0 in PAS1, 0.25 ± 1.0 in PAS2 and 3.63 ± 2.67 in PAS3). Women presenting with PAS3 on ultrasound had significantly more units of PLT transfused (2.37 ± 2.40) compared with those with PAS0 (0.03 ± 0.18), PAS1 (0.0 ± 0.0) or PAS2 (0.0 ± 0.0). Mean operation time was longer in women with PAS3 (184 ± 32 min) compared with those with PAS1 (153 ± 38 min) or PAS2 (161 ± 28 min). Similarly, women with PAS3 had longer hospital stay (7.4 ± 2.1 days) compared with those with PAS0 (3.4 ± 0.6 days), PAS1 (6.4 ± 1.3 days) or PAS2 (5.9 ± 0.8 days). On linear regression analysis, after adjusting for all potential confounders, higher PAS stage was associated independently with a significant increase in EBL (314 (95% CI, 230-399) mL per one-stage increase; P < 0.001), units of PRBC transfused (1.74 (95% CI, 1.33-2.15) per one-stage increase; P < 0.001), units of FFP transfused (1.19 (95% CI, 0.61-1.77) per one-stage increase; P < 0.001), units of PLT transfused (1.03 (95% CI, 0.59-1.47) per one-stage increase; P < 0.001), operation time (38.8 (95% CI, 31.6-46.1) min per one-stage increase; P < 0.001) and length of hospital stay (0.83 (95% CI, 0.46-1.27) days per one-stage increase; P < 0.001). On logistic regression analysis, increased severity of PAS was associated independently with surgical complications (odds ratio, 3.14 (95% CI, 1.36-7.25); P = 0.007), while only PAS3 was associated with admission to the ICU (P < 0.001). All women with PAS0 on ultrasound were classified as having Grade-1 PAS disorder according to the FIGO grading system. Conversely, of the women presenting with PAS1 on ultrasound, 64.1% (95% CI, 48.4-77.3%) were classified as having Grade-3, while 35.9% (95% CI, 22.7-51.6%) were classified as having Grade-4 PAS disorder, according to the FIGO grading system. All women with PAS2 were categorized as having Grade-5 and all those with PAS3 as having Grade-6 PAS disorder according to the FIGO system. CONCLUSION: Ultrasound staging of PAS disorders is feasible and correlates with surgical outcome, depth of invasion and the FIGO clinical grading system. Copyright © 2019 ISUOG. Published by John Wiley & Sons Ltd.

Influence of prenatal diagnosis of abnormally invasive placenta on maternal outcome: systematic review and meta-analysis.

OBJECTIVE: To ascertain the impact of prenatal diagnosis on surgical outcome of women affected by abnormally invasive placenta (AIP). METHODS: MEDLINE, EMBASE, CINAHL and Cochrane databases were searched. Observed outcomes included: gestational age at birth (weeks), amount of blood loss (L), units of red blood cells (RBC), platelets (PLT) and fresh frozen plasma (FFP) transfused, length of stay in hospital and the intensive care unit (ICU) (days), urinary tract injury and infection. Only studies reporting the occurrence of any of the explored outcomes in women with a prenatal compared with an intrapartum diagnosis of AIP were considered eligible for inclusion. Random-effect head-to-head meta-analyses were used to analyze the data. RESULTS: Thirteen studies were included. Women with a prenatal diagnosis of AIP had less blood loss during surgery (mean difference (MD), -0.87; 95% CI, -1.5 to -0.23), had fewer units of RBC (MD, -1.45; 95% CI, -2.9 to -0.04) and FFP (MD, -1.73; 95% CI, -3.3 to -0.2) transfused, and delivered earlier (MD, 1.33 weeks; 95% CI, -2.23 to -0.43) compared with those with an intrapartum diagnosis. The risk of admission to an ICU and length of in-hospital and in-ICU stay were not different between the groups. Prenatal diagnosis of AIP was associated with a higher risk of urinary-tract injury (odds ratio, 2.5; 95% CI, 1.3-4.6), mainly due to the higher prevalence of placenta percreta in the group with AIP diagnosed prenatally. CONCLUSION: Prenatal diagnosis of AIP is associated with reduced hemorrhagic morbidity compared with cases in which such anomalies are detected at delivery. Copyright © 2018 ISUOG. Published by John Wiley & Sons Ltd.

Diagnostic accuracy of first-trimester ultrasound in detecting abnormally invasive placenta in high-risk women with placenta previa.

OBJECTIVE: To ascertain the diagnostic accuracy of ultrasound in detecting abnormally invasive placenta (AIP) during the first trimester of pregnancy (11-14 weeks' gestation) in women at risk for this condition. METHODS: This was a retrospective analysis of data collected prospectively from women at risk for AIP based upon the presence of at least one prior Cesarean section (CS) and/or uterine surgery and placenta previa, who had ultrasound assessment for AIP at the time of the 11-14-week scan. The ultrasound signs explored in the present study were: loss of the clear zone, placental lacunae, bladder wall interruption and uterovesical hypervascularity. The potential of ultrasound and different ultrasound signs to predict the different types of AIP was assessed by computing summary estimates of sensitivity, specificity, diagnostic odds ratio (DOR) and positive (LR+) and negative (LR-) likelihood ratios. RESULTS: One hundred and eighty-eight women with placenta previa and at least one previous CS or uterine surgery were included in the study. All the explored ultrasound signs were associated significantly with the occurrence of AIP. Overall, when at least one ultrasound sign was used to make the diagnosis, ultrasound had a sensitivity of 84.3% (95% CI, 74.7-91.4%), specificity of 61.9% (95% CI, 51.9-71.2%), DOR of 8.6 (95% CI, 4.1-19.3), LR+ of 2.2 (95% CI, 1.7-2.9) and LR- of 0.3 (95% CI, 0.1-0.4) in detecting AIP. Using two ultrasound signs to label a case as positive increased the diagnostic accuracy in terms of specificity, although it did not affect sensitivity. Among the different ultrasound signs, loss of the clear zone had a sensitivity of 84.3% (95% CI, 74.7-91.4%) and a specificity of 81.9% (95% CI, 73.2-88.7%) in detecting AIP, while sensitivities for placental lacunae and bladder wall interruption were 78.3% (95% CI, 67.9-86.6%) and 75.9% (95% CI, 65.3-84.6%), respectively, and specificities were 81.0% (95% CI, 72.1-88.0%) and 99.1% (95% CI, 94.8-100.0%), respectively. The optimal combination of sensitivity and specificity was achieved when at least two imaging signs of AIP were used in the diagnostic algorithm. CONCLUSIONS: AIP can be detected from the first trimester of pregnancy in women at risk for this condition, and ultrasound performed between 11 and 14 weeks' gestation has an overall good diagnostic accuracy for detecting all types of AIP. However, these findings are applicable only to women with placenta previa and prior uterine scar. Copyright © 2018 ISUOG. Published by John Wiley & Sons Ltd.

Outcome of Cesarean scar pregnancy managed expectantly: systematic review and meta-analysis.

OBJECTIVE: To explore the outcome in women managed expectantly following the diagnosis of Cesarean scar pregnancy (CSP). METHODS: An electronic search of MEDLINE, EMBASE and ClinicalTrials.gov databases was performed utilizing combinations of relevant medical subject headings for 'Cesarean scar pregnancy' and 'outcome'. Reference lists of relevant articles and reviews were hand-searched for additional reports. Observed outcomes included: severe first-trimester vaginal bleeding; clinical symptoms (abdominal pain, vaginal bleeding) requiring treatment; uncomplicated miscarriage; complicated miscarriage requiring intervention; first- or second-trimester uterine rupture or hysterectomy; third-trimester bleeding, uterine rupture or hysterectomy; maternal death; incidence of abnormally invasive placenta (AIP); prevalence of placenta percreta; ultrasound signs suggestive of AIP; and live birth. Meta-analyses of proportions using a random-effects model were used to combine data. Cases were stratified based on the presence or absence of embryonic/fetal heart activity at the time of diagnosis. RESULTS: A total of 17 studies (69 cases of CSP managed expectantly, 52 with and 17 without embryonic/fetal heart beat) were included. In women with CSP and embryonic/fetal heart activity, 13.0% (95% CI, 3.8-26.7%) experienced an uncomplicated miscarriage, while 20.0% (95% CI, 7.1-37.4%) required medical intervention. Uterine rupture during the first or second trimester of pregnancy occurred in 9.9% (95% CI, 2.9-20.4%) of cases, while hysterectomy was required in 15.2% (95% CI, 3.6-32.8%) of all cases. Forty (76.9% (95% CI, 65.4-86.5%)) women progressed to the third trimester of pregnancy, of whom 39.2% (95% CI, 15.4-66.2%) experienced severe bleeding. Finally, 74.8% (95% CI, 52.0-92.1%) had a surgical or pathological diagnosis of AIP at delivery and around two-thirds (69.7% (95% CI, 42.8-90.1%)) of them had placenta percreta. In women with CSP but no embryonic/fetal cardiac activity, an uncomplicated miscarriage occurred in 69.1% (95% CI, 47.4-87.1%) of cases, while surgical or medical intervention during or immediately after miscarriage was required in 30.9% (95% CI, 12.9-52.6%). Uterine rupture during the first trimester of pregnancy occurred in 13.4% (95% CI, 2.7-30.3%) of cases, but hysterectomy was not required in any case. CONCLUSIONS: CSP with positive embryonic/fetal heart activity managed expectantly is associated with a high burden of maternal morbidity including severe hemorrhage, early uterine rupture, hysterectomy and severe AIP. Despite this, a significant proportion of pregnancies complicated by CSP may progress to, or close to, term, thus questioning whether termination of pregnancy should be the only therapeutic option offered to these women. Expectant management of CSP with no cardiac activity may be a reasonable option in view of the low likelihood of maternal complications requiring intervention, although close surveillance is advisable to avoid adverse maternal outcome. Copyright © 2017 ISUOG. Published by John Wiley & Sons Ltd.

First-trimester prediction of surgical outcome in abnormally invasive placenta using the cross-over sign.

OBJECTIVE: Ultrasound assessment of the relationship between the ectopic gestational sac and the endometrial line (cross-over sign; COS) in Cesarean scar pregnancy (CSP) has been shown to be useful in predicting the evolution of CSP towards different types of abnormally invasive placenta (AIP). The aim of this study was to ascertain whether the COS can be used to predict surgical outcome in women with AIP. METHODS: A retrospective analysis was performed of early first-trimester (6-8 weeks' gestation) ultrasound images of women with AIP managed in the third trimester of pregnancy. We hypothesized that assessment of COS may identify cases of AIP at higher risk of intra- or postsurgical morbidity. Outcomes explored were estimated blood loss during surgery, need for and amount of packed red blood cells and fresh frozen plasma units required either during or after surgery, operative time, intrasurgical complications, gestational age at birth, delivery < 34 weeks of gestation, length of hospital stay and admission to intensive care unit. Differences in the explored outcomes were assessed among women with different types of COS variant (COS-1, COS-2+ or COS-2-) as observed on first-trimester ultrasound examination. RESULTS: Sixty-eight pregnancies were included in the study. Mean estimated blood loss was higher in AIP pregnancies with COS-1 than in those with COS-2+ (P = 0.039) or COS-2- (P = 0.01). Mean number of packed red blood cell units required during or after the operation was higher in women with COS-1 compared with those with COS-2+ (P = 0.001) and COS-2- (P = 0.029), while there was no difference between pregnancies with COS-2+ and those with COS-2- (P = 0.797). Mean operative time was longer in AIP pregnancies with COS-1 than in those with COS-2+ (P = 0.039) or COS-2- (P = 0.017). Finally, pregnancies with COS-1 were delivered earlier than those with COS-2+ (P = 0.0001) or COS-2- (P = 0.0001). CONCLUSION: First-trimester ultrasound assessment of the relationship between the ectopic gestational sac and the endometrial line (COS) may identify women with AIP who are at higher risk of intra- or postsurgical morbidity. Copyright © 2017 ISUOG. Published by John Wiley & Sons Ltd.

First-trimester detection of abnormally invasive placenta in high-risk women: systematic review and meta-analysis.

OBJECTIVES: The primary aim of this systematic review was to ascertain whether ultrasound signs suggestive of abnormally invasive placenta (AIP) are present in the first trimester of pregnancy. Secondary aims were to ascertain the strength of association and the predictive accuracy of such signs in detecting AIP in the first trimester. METHODS: An electronic search of MEDLINE, EMBASE, CINAHL and Cochrane databases (2000-2016) was performed. Only studies reporting on first-trimester diagnosis of AIP that was subsequently confirmed in the third trimester either during operative delivery or by pathological examination were included. Meta-analysis of proportions, random-effects meta-analysis and hierarchical summary receiver-operating characteristics curve analysis were used to analyze the data. RESULTS: Seven studies, involving 551 pregnancies at high risk of AIP, were included. At least one ultrasound sign suggestive of AIP was detected in 91.4% (95% CI, 85.8-95.7%) of cases with confirmed AIP. The most common ultrasound feature in the first trimester of pregnancy was low implantation of the gestational sac close to a previous uterine scar, which was observed in 82.4% (95% CI, 46.6-99.8%) of cases. Anechoic spaces within the placental mass (lacunae) were observed in 46.0% (95% CI, 10.9-83.7%) and a reduced myometrial thickness in 66.8% (95% CI, 45.2-85.2%) of cases affected by AIP. Pregnancies with a low implantation of the gestational sac had a significantly higher risk of AIP (odds ratio, 19.6 (95% CI, 6.7-57.3)), with a sensitivity and specificity of 44.4% (95% CI, 21.5-69.2%) and 93.4% (95% CI, 90.5-95.7%), respectively. CONCLUSIONS: Ultrasound signs of AIP can be present during the first trimester of pregnancy, even before 11 weeks' gestation. Low anterior implantation of the placenta/gestational sac close to or within the scar was the most commonly seen early ultrasound sign suggestive of AIP, although its individual predictive accuracy was not high. Copyright © 2017 ISUOG. Published by John Wiley & Sons Ltd.

Natural history of Cesarean scar pregnancy on prenatal ultrasound: the crossover sign.

OBJECTIVE: Advances in prenatal imaging techniques have led to an increase in the diagnosis of Cesarean scar pregnancy (CSP). However, antenatal counseling when CSP is diagnosed is challenging, and current evidence is derived mainly from small series reporting high rates of adverse maternal outcomes. The aim of this study was to ascertain the performance of prenatal ultrasound in predicting the natural history of CSP using a new sonographic sign, the crossover sign (COS). METHODS: This was a retrospective analysis of early first-trimester (6-8 weeks' gestation) ultrasound images in women with morbidly adherent placenta (MAP) managed in the third trimester of pregnancy. The relationship between the gestational sac of the CSP, anterior uterine wall and Cesarean scar, defined as the COS, was analyzed to determine whether it could predict evolution in these cases. Odds ratios (ORs) were calculated and logistic regression analysis was performed to investigate the association between different types of COS (COS-1, COS-2+ or COS-2-) and the occurrence of MAP. RESULTS: Sixty-eight pregnancies with MAP were included. The risk of placenta percreta was significantly higher in pregnancies with COS-1 than in those with COS-2 (OR, 6.67 (95% CI, 1.3-33.3)). When evaluating the two variants of COS-2 separately, the risk of placenta percreta was significantly higher in pregnancies with COS-1 vs COS-2+ (OR, 5.83 (95% CI, 1.1-30.2)) and this risk was even higher when comparing cases with COS-1 vs COS-2- (OR, 12.0 (95% CI, 1.9-75.7)). Logistic regression analysis showed that COS-1 was associated independently with severe forms of MAP, such as placenta percreta and increta (OR, 12.85 (95% CI, 2.0-84.0)), while COS-2+ was associated independently with placenta accreta (OR, 4.37 (95% CI, 1.1-17.0)). CONCLUSIONS: Ultrasound assessment of the relationship between the gestational sac of a CSP and the endometrial line (the COS) may help to determine whether a CSP will progress towards a less severe form of MAP, amenable to postnatal treatment, and successful pregnancy outcome. Large prospective studies are needed to confirm our findings and elucidate the natural history of this condition. Copyright © 2016 ISUOG. Published by John Wiley & Sons Ltd.

Counseling in fetal medicine: evidence-based answers to clinical questions on morbidly adherent placenta.

Although the incidence of morbidly adherent placenta (MAP) has risen progressively in the last two decades, there remains uncertainty about the diagnosis and management of this condition. The aim of this review is to provide up-to-date and evidence-based answers to common clinical questions regarding the diagnosis and management of MAP. Different risk factors have been associated with MAP; however, previous Cesarean section and placenta previa are the most frequently associated. Ultrasound is the primary method for diagnosing MAP and has a good overall diagnostic accuracy for its detection. When considering the different ultrasound signs of MAP, color Doppler seems to provide the best diagnostic performance. Magnetic resonance imaging has the same accuracy in diagnosing MAP as does ultrasound examination; its use should be considered when a resective procedure, such as hysterectomy, is planned as it can provide detailed information about the topography of placental invasion and predict difficulties that may arise in surgery. The optimal gestational age for delivery in pregnancies with MAP is yet to be established; planning surgery between 34 and 36 weeks of gestation provides the best balance between fetal maturity and the risk of unexpected episodes of heavy bleeding, which are more likely to occur with delivery after this timepoint, especially in severe cases of MAP. The optimal surgical approach to MAP depends on multiple factors, including availability of an experienced team, specific surgical skills and hospital resources. Copyright © 2015 ISUOG. Published by John Wiley & Sons Ltd.

Foley balloon catheter to prevent or manage bleeding during treatment for cervical and Cesarean scar pregnancy.

OBJECTIVE: To demonstrate the efficacy of placement and inflation of Foley balloon catheters prophylactically to prevent, or as an adjuvant therapy to control, bleeding in women undergoing treatment for Cesarean scar pregnancy (CSP) or cervical pregnancy (CxP). METHODS: This was a retrospective study of 18 women with either CSP (n = 16) or CxP (n = 2), who underwent Foley balloon catheter placement under continuous transvaginal or transabdominal ultrasound guidance to prevent or manage bleeding following treatment, which in most cases comprised local (intragestational sac) and intramuscular (IM) methotrexate (MTX) injections. In eight cases, the balloon catheter was placed immediately following local and/or IM MTX treatment, either because of bleeding or prophylactically; in eight cases, the catheter was placed as part of a two-step protocol, with patients first treated with local and IM MTX injection, then suction aspiration on Day 4 or 5, followed by planned insertion of a balloon catheter; in one patient the balloon was placed on Day 21 after local and IM MTX treatment, due to sudden bleeding; and in one case of a heterotopic pregnancy, one intrauterine and one cervical, the balloon was placed due to severe bleeding. Human chorionic gonadotropin (hCG) levels were evaluated weekly following MTX injection. RESULTS: Gestational ages at balloon placement ranged between 5 and 12 + 2 weeks. All embryos/fetuses, with the exception of the cervical heterotopic one, had heart activity and catheter placement was well-tolerated by all women. The balloon tamponade effectively reduced or prevented maternal vaginal bleeding in all except one patient; this woman had a heterotopic CxP and required abdominal robotic cerclage to control the bleeding. Catheters were kept in place for a mean of 3.6 (range, 1-6) days. hCG levels returned to low or zero levels within 19-82 days following MTX injection. Fifteen women required antibiotic treatment following the procedure. One woman with CSP developed an arteriovenous malformation requiring uterine artery embolization. CONCLUSION: Ultrasound-guided placement and inflation of Foley balloon catheters was easy to perform and well-tolerated by patients undergoing treatment for CSP or CxP, and successfully prevented or helped in the management of bleeding complications. Based on our experience and previous publications we suggest having the option of balloon catheter insertion available when local treatment of CSP or CxP is undertaken.

Morbidly adherent placenta: evaluation of ultrasound diagnostic criteria and differentiation of placenta accreta from percreta.

OBJECTIVES: To evaluate the diagnostic accuracy of two-dimensional (2D) gray-scale and color Doppler and three-dimensional (3D) power Doppler sonographic criteria for morbidly adherent placenta (MAP), and to identify criteria to help distinguish placenta accreta from placenta percreta. METHODS: We enrolled 187 patients with placenta previa and history of uterine surgery and performed transabdominal and transvaginal ultrasound examination for early detection of MAP. With 2D gray-scale transabdominal and transvaginal ultrasonography, we investigated loss/irregularity of the echolucent area between the uterus and the placenta ('clear space'), thinning or interruption of the hyperechoic interface between the uterine serosa and the bladder wall and the presence of turbulent placental lacunae with high-velocity flow (>15 cm/s). Using transabdominal 3D power Doppler, we evaluated the hypervascularity of the uterine serosa-bladder wall interface and irregular intraplacental vascularization. Ultrasound findings were reviewed against the final diagnosis made during Cesarean section (CS). RESULTS: MAP was detected on CS in 41 patients. All of them had an anterior placenta previa (34 major and seven minor) and had undergone at least one previous CS. The evaluated sonographic criteria showed good diagnostic performance; in MAP patients at least two out of five criteria were detected, with at most one of the criteria present in patients without MAP. Loss/irregularity of clear space used as a single criterion was responsible for the most false positives, demonstrating a low positive predictive value. Irregular intraplacental vascularization with tortuous confluent vessels affecting the entire width of the placenta, and hypervascularity of the entire uterine serosa-bladder wall interface, were only detected, on 3D power Doppler, in cases of placenta percreta. CONCLUSIONS: The reviewed ultrasound criteria may be useful for the prenatal diagnosis of MAP and to differentiate between placenta accreta and placenta percreta; 3D power Doppler techniques were an important aid in the diagnosis.

ETHE1 mutations are specific to ethylmalonic encephalopathy.

Mutations in ETHE1, a gene located at chromosome 19q13, have recently been identified in patients affected by ethylmalonic encephalopathy (EE). EE is a devastating infantile metabolic disorder, characterised by widespread lesions in the brain, hyperlactic acidaemia, petechiae, orthostatic acrocyanosis, and high levels of ethylmalonic acid in body fluids. To investigate to what extent ETHE1 is responsible for EE, we analysed this gene in 29 patients with typical EE and in 11 patients presenting with early onset progressive encephalopathy with ethylmalonic aciduria (non-EE EMA). Frameshift, stop, splice site, and missense mutations of ETHE1 were detected in all the typical EE patients analysed. Western blot analysis of the ETHE1 protein indicated that some of the missense mutations are associated with the presence of the protein, suggesting that the corresponding wild type amino acid residues have a catalytic function. No ETHE1 mutations were identified in non-EE EMA patients. Experiments based on two dimensional blue native electrophoresis indicated that ETHE1 protein works as a supramolecular, presumably homodimeric, complex, and a three dimensional model of the protein suggests that it is likely to be a mitochondrial matrix thioesterase acting on a still unknown substrate. Finally, the 625G-->A single nucleotide polymorphism in the gene encoding the short chain acyl-coenzyme A dehydrogenase (SCAD) was previously proposed as a co-factor in the aetiology of EE and other EMA syndromes. SNP analysis in our patients ruled out a pathogenic role of SCAD variants in EE, but did show a highly significant prevalence of the 625A alleles in non-EE EMA patients.

Evidence that elongation of the catalytic loop of the Azotobacter vinelandii rhodanese changed selectivity from sulfur- to phosphate-containing substrates.

Recent investigations have shown that the rhodanese domains, ubiquitous structural modules which might represent an example of conserved structures with possible functional diversity, are structurally related to the catalytic subunit of Cdc25 phosphatase enzymes. The major difference characterizing the active-site of the Azotobacter vinelandii rhodanese RhdA, with respect to the closely related Cdc25s (A, B, C), is that in Cdc25 phosphatases the active site loop [His-Cys-(X)5-Arg] is one residue longer than in RhdA [His-Cys-(X)4-Arg]. According to the hypothesis that the length of the RhdA active-site loop should play a key role in substrate recognition and catalytic activity, RhdA scaffold was the starting point for producing mutants with single-residue insertion to generate the catalytic loop HCQTHAHR (in RhdA-Ala) and HCQTHSHR (in RhdA-Ser). Analyses of the catalytic performances of the engineered RhdAs revealed that elongation of the catalytic loop definitely compromised the ability to catalyze sulfur transfer reactions, while it generated 'phosphatase' enzymes able to interact productively with the artificial substrate 3-O-methylfluorescein phosphate. Although this study is restricted to an example of rhodanese modules (RhdA), it provided experimental evidence of the hypothesis that a specific mutational event (a single-residue insertion or deletion in the active-site loop) could change the selectivity from sulfur- to phosphate-containing substrates (or vice versa).

Bread wheat gliadin cytotoxicity: a new three-dimensional cell model.

BACKGROUND: In an attempt to clarify the role of gliadin toxicity in the pathogenesis of gluten intolerance (celiac disease), previous in vitro studies have been based on two-dimensional human cell cultures. However, the specific morphological and biochemical properties of in vivo tissue are better maintained in three-dimensional cell cultures (multicellular spheroids, MCS). The aim of this study was to develop a three-dimensional in vitro model to investigate the effects of gliadin on epithelial cells and broaden our understanding of the early tissue damage occurring in celiac disease. METHODS: The three-dimensionally growing Lovo cell line was exposed to increasing concentrations of peptic-tryptic-digested bread wheat gliadin (from 125 to 1000 microg/mL) for 7 days in order to evaluate cell viability (colony-forming assay), and at the standard concentration of 500 microg/mL for 7 days in order to evaluate MCS diameters, volumes and cell morphology using light and electron microscopy. RESULTS: In comparison with the controls, the cell viability of the gliadin-treated MCS was significantly reduced (20-80%), but there was no difference in size. Various degrees of cell damage (autophagic vacuoles and intra-cytoplasmic lipid-like droplets) were detected by both light and electron microscopy. CONCLUSION: This is the first study investigating the effects of gliadin on MCS. Lovo MCS seem to be responsive to gliadin exposure, thus confirming previous results obtained using two-dimensional cell cultures. The data suggest that three-dimensional cell cultures may be useful in broadening our understanding of some of the early effects of gliadin peptides on epithelial cells.

In vitro cytotoxic effect of bread wheat gliadin on the LoVo human adenocarcinoma cell line.

The pathogenesis of celiac disease is not completely understood but, although the initial step of the process is still unclear, an altered immune response seems to play a major role. Previous studies of the biological properties of gliadin have highlighted its cytotoxic effects, and the aim of this study was to develop an in vitro technique to study them. The LoVo (human colon adenocarcinoma) cell line grown in two-dimensional cultures was exposed to different concentrations of digested bread wheat gliadin (62, 125, 250, 500 and 750 microg/ml) for 48 h, after which cell growth and oxidative balance (the content of reduced glutathione (GSH), and peroxidase, transferase and reductase activity) was evaluated. Other food proteins were used as controls. Our data revealed a statistically significant inhibition of cell growth in proportion to the gliadin concentration (from 26 to 100%), combined with a decrease in GSH content (-38% at 500 microg/ml) and reduced enzymatic activity (-30% at 500 microg/ml). The controls did not show any noxious effect. Our results confirm the usefulness of LoVo cells in evaluating gliadin cytotoxicity and that they can be used to investigate the biological properties of gliadin.

A persulfurated cysteine promotes active site reactivity in Azotobacter vinelandii Rhodanese.

Active site reactivity and specificity of RhdA, a thiosulfate:cyanide sulfurtransferase (rhodanese) from Azotobacter vinelandii, have been investigated through ligand binding, site-directed mutagenesis, and X-ray crystallographic techniques, in a combined approach. In native RhdA the active site Cys230 is found persulfurated; fluorescence and sulfurtransferase activity measurements show that phosphate anions interact with Cys230 persulfide sulfur atom and modulate activity. Crystallographic analyses confirm that phosphate and hypophosphite anions react with native RhdA, removing the persulfide sulfur atom from the active site pocket. Considering that RhdA and the catalytic subunit of Cdc25 phosphatases share a common three-dimensional fold as well as active site Cys (catalytic) and Arg residues, two RhdA mutants carrying a single amino acid insertion at the active site loop were designed and their phosphatase activity tested. The crystallographic and functional results reported here show that specific sulfurtransferase or phosphatase activities are strictly related to precise tailoring of the catalytic loop structure in RhdA and Cdc25 phosphatase, respectively.

Properties of the Escherichia coli rhodanese-like protein SseA: contribution of the active-site residue Ser240 to sulfur donor recognition.

The product of Escherichia coli sseA gene (SseA) was the subject of the present investigation aimed to provide a tool for functional classification of the bacterial proteins of the rhodanese family. E. coli SseA contains the motif CGSGVTA around the catalytic cysteine (Cys238). In eukaryotic sulfurtransferases this motif discriminates for 3-mercaptopyruvate:cyanide sulfurtransferase over thiosulfate:cyanide sulfurtransferases (rhodanese). The biochemical characterization of E. coli SseA allowed the identification of the first prokaryotic protein with a preference for 3-mercaptopyruvate as donor substrate. Replacement of Ser240 with Ala showed that the presence of a hydrophobic residue did not affect the binding of 3-mercaptopyruvate, but strongly prevented thiosulfate binding. On the contrary, substitution of Ser240 with an ionizable residue (Lys) increased the affinity for thiosulfate.