Chromosomal microarray vs. NIPS: analysis of 5541 low-risk pregnancies.

PURPOSE: To evaluate the diagnostic yield of chromosomal microarray (CMA) in pregnancies with normal ultrasound. METHODS: This retrospective cohort analysis included all pregnancies with normal ultrasound undergoing CMA testing between the years 2010 and 2016. We calculated the rate of detection of clinically significant CMA findings in the whole cohort and according to various indications. RESULTS: Of 5541 CMA analyses, clinically significant findings were yielded in 78 cases (1.4%). Of these, 31 (39.7%) variants could have theoretically been detected by karyotyping (e.g., sized above 10 Mb), and 28 (35.9%) by noninvasive prenatal screening aimed at five common aneuploidies. Of the 47 submicroscopic findings detectable by CMA only, the majority (37 cases, 78.7%) represented known recurrent syndromes. Detection of clinically significant CMA findings in women with no indication for invasive testing was 0.76% (21/2752), which was significantly lower compared with 1.8% in advanced maternal age group (41/2336), 2.8% in abnormal biochemical serum screening (6/211), and 4.1% (10/242) in fetuses with sonographic soft markers. CONCLUSION: Clinically significant CMA aberrations are detected in 1 of 71 pregnancies with normal ultrasound, and in 1 of 131 women with no indication for invasive testing. Thus, CMA might be recommended a first-tier test in pregnancies with normal ultrasound.

When genotype is not predictive of phenotype: implications for genetic counseling based on 21,594 chromosomal microarray analysis examinations.

PurposeTo compare the frequency of copy-number variants (CNVs) of variable penetrance in low-risk and high-risk prenatal samples and postnatal samples.MethodsTwo cohorts were categorized according to chromosomal microarray analysis (CMA) indication: group I, low-risk prenatal-women with uneventful pregnancy (control group); group II, high-risk prenatal-women whose fetuses had congenital malformations; and group III, postnatal-individuals with unexplained developmental delay/intellectual disability, autism spectrum disorders, or multiple congenital anomalies. CNVs were categorized based on clinical penetrance: (i) high (>40%), (ii) moderate (10-40%), and (iii) low (<10%).ResultsFrom 2013 to 2016, 21,594 CMAs were performed. The frequency of high-penetrance CNVs was 0.1% (21/15,215) in group I, 0.9% (26/2,791) in group II, and 2.6% (92/3,588) in group III. Moderate-penetrance CNV frequency was 0.3% (47/15,215), 0.6% (19/2,791), and 1.2% (46/3,588), respectively. These differences were statistically significant. The frequency of low-penetrance CNVs was not significantly different among groups: 0.6% (85/15,215), 0.9% (25/2,791), and 1.0% (35/3,588), respectively.ConclusionHigh-penetrance CNVs might be a major factor in the overall heritability of developmental, intellectual, and structural anomalies. Low-penetrance CNV alone does not seem to contribute to these anomalies. These data may assist pre- and posttest CMA counseling.

Cytogenetic analysis in fetuses with late onset abnormal sonographic findings.

OBJECTIVE: To determine the rate of chromosomal cytogenetic abnormalities in fetuses with late onset abnormal sonographic findings. DESIGN: Retrospective cohort of women who underwent amniocentesis at or beyond 23 weeks of gestation, for fetal karyotype and chromosomal microarray analysis, indicated due to late onset abnormal sonographic findings. RESULTS: All 103 fetuses had a normal karyotype. Ninety-five women also had chromosomal microarray analysis (CMA) performed. The detection rate of abnormal CMA (5/95, 5.3%) was similar to that of women who underwent amniocentesis due to abnormal early onset ultrasound findings detected at routine prenatal screening tests during the first or early second trimester (7.3%, P=0.46) and significantly higher than that for women who underwent amniocentesis and CMA upon request, without a medical indication for CMA (0.99%, P<0.0001). CONCLUSIONS: Late onset sonographic findings are an indication for amniocentesis, and if performed, CMA should be applied to evaluate fetuses with late onset abnormal sonographic findings.

Neurologic complications of thiamine (B1) deficiency following bariatric surgery in adolescents.

BACKGROUND: The prevalence of obesity among children and adolescents is rising and poses a major health concern. Bariatric surgery is well established in adults and has become an option for adolescents. Thiamine (B1) deficiency is common following bariatric surgery in adults. It may present as Beri-Beri, Wernicke encephalopathy, or Korsakoff psychosis. OBJECTIVE: Our aim was to describe the clinical features, diagnosis, and treatment of adolescents who presented with B1 deficiency after bariatric surgery at one center, and to summarize the data from the literature. PATIENTS: Three adolescents with morbid obesity (two boys and one girl, aged 15.5 to- 17-years-old), presented at Schneider Children's Medical Center of Israel with progressive lower limb pain and weakness 2-3 month following a bariatric procedure (sleeve gastrectomy or narrowing of a bariatric band). The girl also had upper limb involvement and cerebellar signs. All three were non-compliant with micronutrient supplementation. After admission, they received intravenous B1 and oral multivitamin supplementation, and their symptoms improved considerably. CONCLUSIONS: Micronutrient supplementation following bariatric surgery is crucial to prevent deficiencies. In adolescents, compliance with micronutrient supplementation should be assessed before and after such surgery. Thiamine deficiency may cause polyneuropathy, among other symptoms. Treatment reduces the severity of neurological complications.