Novel Splicing Variant in the PMM2 Gene in a Patient With PMM2-CDG Syndrome Presenting With Pericardial Effusion: A Case Report

Congenital disorders of glycosylation (CDG) are a rapidly growing family of genetic diseases with the phosphomannomutase 2 (PMM2)-CDG being the most common form of CDG. Most of these monogenic diseases are autosomal recessive and have multi-systemic manifestations, mainly psychomotor retardation, facial dysmorphisms, characteristic distribution of the fat pads, and variable coagulation abnormalities. The association of fetal hydrops with CDG has been reported, and pericardial effusion was also rarely observed in patients with PMM2-CDG. Here we describe an infant boy with PMM2-CDG. The diagnosis was suspected based on inverted nipples, fat pads, and combined coagulopathy. However, the primary symptom was progressive pericardial effusion leading to patient death at the age of 3 months. Screening for CDG performed by the use of isoelectric focusing of serum transferrin showed a typical PMM2-CDG pattern. Exome sequencing revealed one common pathogenic variant (c.691G > A/p.Val231Met) and one novel variant (c.447 + 3dupA) in the PMM2 gene. Both PMM2 variants were further confirmed by Sanger sequencing in both the proband and the parents’ DNA. The novel variant was predicted to result in loss of donor splice site, and the analysis at mRNA level confirmed that it leads to exon five skipping (r.348_447del) and causes premature termination of translation to the protein (p.G117Kfs^∗4), therefore is classified as likely pathogenic. Although there is no curative therapy for the PMM2-CDG at the moment, the other supportive care options are available to be offered. The definite diagnosis of PMM2-CDG can also assist in the process of genetic counseling, family planning, and preimplantation genetic diagnosis.

Fetal hemodynamic response to aortic valvuloplasty and postnatal outcome: a European multicenter study

OBJECTIVE

Fetal aortic stenosis may progress to hypoplastic left heart syndrome. Fetal valvuloplasty (FV) has been proposed to improve left heart hemodynamics and maintain biventricular (BV) circulation. The aim of this study was to assess FV efficacy by comparing survival and postnatal circulation between fetuses that underwent FV and those that did not.

METHODS

This was a retrospective multicenter study of fetuses with aortic stenosis that underwent FV between 2005 and 2012, compared with contemporaneously enrolled natural history (NH) cases sharing similar characteristics at presentation but not undergoing FV. Main outcome measures were overall survival, BV-circulation survival and survival after birth. Secondary outcomes were hemodynamic change and left heart growth. A propensity score model was created including 54/67 FV and 60/147 NH fetuses. Analyses were performed using logistic, Cox or linear regression models with inverse probability of treatment weighting (IPTW) restricted to fetuses with a propensity score of 0.14-0.9, to create a final cohort for analysis of 42 FV and 29 NH cases.

RESULTS

FV was technically successful in 59/67 fetuses at a median age of 26 (21-34) weeks. There were 7/72 (10%) procedure-related losses, and 22/53 (42%) FV babies were delivered at < 37 weeks. IPTW demonstrated improved survival of liveborn infants following FV (hazard ratio, 0.38; 95% CI, 0.23-0.64; P = 0.0001), after adjusting for circulation and postnatal surgical center. Similar proportions had BV circulation (36% for the FV cohort and 38% for the NH cohort) and survival was similar between final circulations. Successful FV cases showed improved hemodynamic response and less deterioration of left heart growth compared with NH cases (P ≤ 0.01).

CONCLUSIONS

We report improvements in fetal hemodynamics and preservation of left heart growth following successful FV compared with NH. While the proportion of those achieving a BV circulation outcome was similar in both cohorts, FV survivors showed improved survival independent of final circulation to 10 years' follow-up. However, FV is associated with a 10% procedure-related loss and increased prematurity compared with the NH cohort, and therefore the risk-to-benefit ratio remains uncertain. We recommend a carefully designed trial incorporating appropriate and integrated fetal and postnatal management strategies to account for center-specific practices, so that the benefits achieved by fetal therapy vs surgical strategy can be demonstrated clearly. Copyright © 2017 ISUOG. Published by John Wiley & Sons Ltd.

Fetal aortopulmonary window: case series and review of the literature

Aortopulmonary window is a rare congenital cardiac anomaly characterized by communication between the aorta and the pulmonary artery above the semilunar valves. Prenatal diagnosis is rare. We report four fetuses with aortopulmonary window and review the relevant literature. Approximately half of the reported cases had additional cardiac defects. None had chromosomal abnormalities. In cases with normal cardiac connections, the diagnosis can be made prenatally on the standard three-vessel view, as seen in two of our cases. In one fetus with complete transposition of the great arteries, the diagnosis was made retrospectively on sagittal views. In the remaining case, the window was seen postnatally but could not be identified retrospectively due to the abnormal superoinferior relationship of the ventricles and vessels. Copyright © 2016 ISUOG. Published by John Wiley & Sons Ltd.

Does First-Trimester Screening Modify the Natural History of Congenital Heart Disease?

Background:

The study analyzed the impact of first-trimester screening on the spectrum of congenital heart defects (CHDs) later in pregnancy and on the outcome of fetuses and children born alive with a CHD.

Methods:

The spectrum of CHDs, associated comorbidities, and outcome of fetuses, either diagnosed with a CHD in the first trimester (Group I, 127 fetuses) or only in the second-trimester screening (Group II, 344 fetuses), were analyzed retrospectively between 2007 and 2013. Second-trimester fetuses diagnosed with a CHD between 2007 and 2013 were also compared with Group III (532 fetuses diagnosed with a CHD in the second trimester from 1996 to 2001, the period before first-trimester screening was introduced).

Results:

The spectrum of CHDs diagnosed in the first and second trimesters in the same time period differed significantly, with a greater number of comorbidities ( P <0.0001), CHDs with univentricular outcome ( P <0.0001), intrauterine deaths ( P =0.01), and terminations of pregnancy ( P <0.0001) in Group I compared with Group II. In Group III, significantly more cases of CHDs with univentricular outcome ( P <0.0001), intrauterine demise ( P =0.036), and early termination ( P <0.0001) were identified compared with fetuses diagnosed with CHDs in the second trimester between 2007 and 2013. The spectrum of CHDs seen in the second-trimester groups differed after first-trimester screening was implemented.

Conclusions:

First-trimester screening had a significant impact on the spectrum of CHDs and the outcomes of pregnancies with CHDs diagnosed in the second trimester. Early detection of severe forms of CHDs and significant comorbidities resulted in an increased pregnancy termination rate in the first trimester.

Secondary Combined Immunodeficiency in Pediatric Patients after the Fontan Operation: Three Case Reports

The Fontan operation or total cavopulmonal connection (TCPC) is a palliative surgical correction of rare and complex inborn cardiac malformations that are characterized by univentricular circulation. Protein-losing enteropathy (PLE) develops in 4-13% of patients after the Fontan procedure. Fontan-related PLE leads to secondary combined immunodeficiency marked by hypogammaglobulinemia and predominantly CD4+ lymphocytopenia. Here, we present 3 case reports of patients with secondary immunodeficiency after the Fontan operation. The severity of hypogammaglobulinemia correlated with the nature of the infectious complications; however, clinical manifestations of T cell deficiency such as severe viral or opportunistic infections were not observed. The clinical consequences of the secondary combined immunodeficiency were modified by immunoglobulin replacement treatment and antibiotic prophylaxis. Heart transplantation led to the resolution of PLE signs and the restitution of IgG levels in 1 transplanted patient. Our experience shows that the immunological follow-up was delayed in all 3 patients. We suggest that all patients should be followed regularly by a clinical immunologist after the Fontan surgery.

Natural history of 107 cases of fetal aortic stenosis from a European multicenter retrospective study

OBJECTIVES

Fetal aortic valvuloplasty (FV) aims to prevent fetal aortic valve stenosis progressing into hypoplastic left heart syndrome (HLHS), which results in postnatal univentricular (UV) circulation. Despite increasing numbers of FVs performed worldwide, the natural history of the disease in fetal life remains poorly defined. The primary aim of this study was to describe the natural history of fetal aortic stenosis, and a secondary aim was to test previously published criteria designed to identify cases of emerging HLHS with the potential for a biventricular (BV) outcome after FV.

METHODS

From a European multicenter retrospective study of 214 fetuses with aortic stenosis (2005-2012), 107 fetuses in ongoing pregnancies that did not undergo FV were included in this study and their natural history was reported. We examined longitudinal changes in Z-scores of aortic and mitral valve and left ventricular dimensions and documented direction of flow across the foramen ovale and aortic arch, and mitral valve inflow pattern and any gestational changes. Data were used to identify fetuses satisfying the Boston criteria for emerging HLHS and estimate the proportion of these that would have been ideal FV candidates. We applied the threshold score whereby a score of 1 was assigned to fetuses for each Z-score meeting the following criteria: left ventricular length and width > 0; mitral valve diameter > -2; aortic valve diameter > -3.5; and pressure gradient across either the mitral or aortic valve > 20 mmHg. We compared the predicted circulation with known survival and final postnatal circulation (BV, UV or conversion from BV to UV).

RESULTS

Among the 107 ongoing pregnancies there were eight spontaneous fetal deaths and 99 livebirths. Five were lost to follow-up, five had comfort care and four had mild aortic stenosis not requiring intervention. There was intention-to-treat in these 85 newborns but five died prior to surgery, before circulation could be determined, and thus 80 underwent postnatal procedures with 44 BV, 29 UV and seven BV-to-UV circulatory outcomes. Of newborns with intention-to-treat, 69/85 (81%) survived ≥ 30 days. Survival at median 6 years was superior in cases with BV circulation (P = 0.041). Those with a postnatal UV circulation showed a trend towards smaller aortic valve diameters at first scan than did the BV cohort (P = 0.076), but aortic valve growth velocities were similar in both cohorts to term. In contrast, the mitral valve diameter was significantly smaller at first scan in those with postnatal UV outcomes (P = 0.004) and its growth velocity (P = 0.008), in common with the left ventricular inlet length (P = 0.004) and width (P = 0.002), were reduced significantly by term in fetuses with UV compared with BV outcome. Fetal data, recorded before 30 completed gestational weeks, from 70 treated neonates were evaluated to identify emerging HLHS. Forty-four had moderate or severe left ventricular depression and 38 of these had retrograde flow in the aortic arch and two had left-to-right flow at atrial level and reversed a-waves in the pulmonary veins. Thus 40 neonates met the criteria for emerging HLHS and BV circulation was documented in 13 (33%). Of these 40 cases, 12 (30%) had a threshold score of 4 or 5, of which five (42%) had BV circulation without fetal intervention.

CONCLUSIONS

The natural history in our cohort of fetuses with aortic stenosis and known outcomes shows that a substantial proportion of fetuses meeting the criteria for emerging HLHS, with or without favorable selection criteria for FV, had a sustained BV circulation without fetal intervention. This indicates that further work is needed to refine the selection criteria to offer appropriate therapy to fetuses with aortic stenosis. Copyright © 2016 ISUOG. Published by John Wiley & Sons Ltd.

Sonographic predictors of surgery in fetal coarctation of the aorta

OBJECTIVES

Isolated fetal coarctation of the aorta (CoA) has high false-positive diagnostic rates by cardiologists in tertiary centers. Isthmal diameter Z-scores (I), ratio of isthmus to duct diameters (I:D), and visualization of CoA shelf (Shelf) and isthmal flow disturbance (Flow) distinguish hypoplastic from normal aortic arches in retrospective studies, but their ability to predict a need for perinatal surgery is unknown. The aim of this study was to determine whether these four sonographic features could differentiate prenatally cases which would require neonatal surgery in a prospective cohort diagnosed with CoA by a cardiologist.

METHODS

From 83 referrals with cardiac disproportion (January 2006 to August 2010), we identified 37 consecutive fetuses diagnosed with CoA. Measurements of I and I:D were made and the presence of Shelf or Flow recorded. Sensitivity, specificity and areas under receiver-operating characteristics curves, using previously reported limits of I < - 2 and I:D < 0.74, as well as Shelf and Flow were compared at first and final scan. Associations between surgery and predictors were compared using multivariable logistic regression and changes in measurements using ANCOVA.

RESULTS

Among the 37 fetuses, 30 (81.1%) required surgery and two with an initial diagnosis of CoA were revised to normal following isthmal growth, giving an 86% diagnostic accuracy at term. The median age at first scan was 22.4 (range. 16.6-7.0) weeks and the median number of scans per fetus was three (range, one to five). I < - 2 at final scan was the most powerful predictor (odds ratio, 3.6 (95% CI, 0.47-27.3)). Shelf was identified in 66% and Flow in 50% of fetuses with CoA.

CONCLUSION

Incorporation of these four sonographic parameters in the assessment of fetuses with suspected CoA at a tertiary center resulted in better diagnostic precision regarding which cases would require neonatal surgery than has been reported previously.

Isolated Atrioventricular Block in the Fetus

Background—

Isolated complete atrioventricular block in the fetus is a rare but potentially lethal condition in which the effect of steroid treatment on outcome is unclear. The objective of this work was to study risk factors associated with death and the influence of steroid treatment on outcome.

Methods and Results—

We studied 175 fetuses diagnosed with second- or third-degree atrioventricular block (2000–2007) retrospectively in a multinational, multicenter setting. In 80% of 162 pregnancies with documented antibody status, atrioventricular block was associated with maternal anti-Ro/SSA antibodies. Sixty-seven cases (38%) were treated with fluorinated corticosteroids for a median of 10 weeks (1–21 weeks). Ninety-one percent were alive at birth, and survival in the neonatal period was 93%, similar in steroid-treated and untreated fetuses, regardless of degree of block and/or presence of anti-Ro/SSA. Variables associated with death were gestational age <20 weeks, ventricular rate ≤50 bpm, fetal hydrops, and impaired left ventricular function at diagnosis. The presence of ≥1 of these variables was associated with a 10-fold increase in mortality before birth and a 6-fold increase in the neonatal period independently of treatment. Except for a lower gestational age at diagnosis in treated than untreated (23.4±2.9 versus 24.9±4.9 weeks; P =0.02), risk factors were distributed equally between treatment groups. Two-thirds of survivors had a pacemaker by 1 year of age; 8 children developed cardiomyopathy.

Conclusions—

Risk factors associated with a poor outcome were gestation <20 weeks, ventricular rate ≤50 bpm, hydrops, and impaired left ventricular function. No significant effect of treatment with fluorinated corticosteroids was seen.

Morphological and Physiological Predictors of Fetal Aortic Coarctation

Background— Prenatal diagnosis of aortic coarctation suffers from high false-negative rates at screening and poor specificity.

Methods and Results— This retrospective study tested the applicability of published aortic arch and ductal Z scores (measured just before the descending aorta in the 3-vessel and tracheal view) and their ratio on 200 consecutive normal controls at a median of 22±0 gestational weeks (range, 15±4 to 38±4 weeks). Second, this study tested the ability of serial Z scores to distinguish fetuses with coarctation within a cohort with ventricular and/or great arterial disproportion detected at screening or fetal echocardiography. Third, it evaluated the diagnostic significance of associated cardiac lesions, coarctation shelf, and isthmal flow disturbance. We studied 44 fetuses with suspected coarctation at 24±0 weeks (range, 17±3 to 37±4 weeks). Receiver-operating characteristic curves were created. Logistic regression tested the association between z scores, additional cardiac diagnoses, and coarctation. Good separation was found of isthmal Z scores for cases requiring surgery from controls and false-positive cases, and receiver-operating characteristic curves showed an excellent area under the curve for isthmal Z score (0.963) and isthmal-to-ductal ratio (0.969). Serial isthmal Z scores improved to >−2 in suspected cases with normal outcomes; those requiring surveillance or surgery remained <−2. Minor lesions did not increase the diagnostic specificity of coarctation, but isthmal flow disturbance increased the odds ratio of true coarctation versus arch hypoplasia 16-fold.

Conclusions— Isthmal Z scores and isthmal-to-ductal ratio are sensitive indicators of fetal coarctation. Serial measurements and abnormal isthmal flow patterns improve diagnostic specificity and may reduce false positives.