Microarray analysis has no additional value in fetal aberrant right subclavian artery: description of 268 pregnancies and systematic literature review

OBJECTIVES

Fetal aberrant right subclavian artery (ARSA) is a relatively common sonographic finding. Several studies have reported a significant association between ARSA and Down syndrome, as well as 22q11.2 microdeletion. The objective of this study was to assess the risk of abnormal chromosomal microarray analysis (CMA) findings in a large cohort of pregnancies with fetal ARSA as an isolated, as well as a non-isolated, sonographic anomaly. A secondary objective was to review the literature, examining the frequency of chromosomal microarray aberrations in fetuses with isolated ARSA.

METHODS

Data from all pregnancies referred for invasive testing and CMA due to sonographic diagnosis of fetal ARSA, between 2013 and 2017, were obtained retrospectively from the computerized database of the Israeli Ministry of Health. The rate of clinically significant CMA findings in these fetuses was compared to that in a local control population of 2752 low-risk pregnancies with normal ultrasound and serum screening results. In addition, a literature search was conducted in PubMed, from inception to February 2018, of original studies in the English language describing the frequency and nature of microscopic and submicroscopic aberrations in fetuses with isolated ARSA.

RESULTS

Of 246 pregnancies with isolated ARSA that underwent CMA analysis, a clinically significant finding was detected in one (0.4%) pregnancy (trisomy 21). This rate did not differ significantly from that in the control population (P = 0.1574). Of 22 fetuses with non-isolated ARSA, one (4.5%) additional case of trisomy 21 was noted. The frequency of trisomy 21 in this cohort also did not differ from that in the control population (relative risk, 5.5 (95% CI, 0.8-37.6)). The literature search yielded 13 additional relevant papers, encompassing 333 cases of isolated ARSA. Of 579 cases overall (including those of the present study), 13 (2.2%) cases of trisomy 21 were detected, with no cases of 22q11.2 microdeletion.

CONCLUSION

While an association may exist between non-isolated ARSA and Down syndrome, isolated ARSA might better serve as a soft marker for Down syndrome, rather than a routine indication for invasive prenatal testing. Copyright © 2018 ISUOG. Published by John Wiley & Sons Ltd.

The outcome of ulcerative colitis patients undergoing pouch surgery is determined by pre-surgical factors

BACKGROUND

Pouch surgery, a common intervention for ulcerative colitis (UC) complications, is often associated with the development of pouchitis.

AIM

To identify predictors of pouch outcome in a cohort of patients with UC.

METHODS

We conducted a retrospective unmatched case-cohort study in a tertiary IBD referral centre. Adult patients with UC were classified into the worst phenotype throughout follow-up: normal pouch, a form of chronic pouchitis (either chronic pouchitis or Crohn's like disease of pouch [CLDP]), or episodic recurrent acute pouchitis (RAP). Risk factors for pouchitis (chronic forms) were detected using statistical models.

RESULTS

Two hundred and fifty-three pouch patients were followed up for 13.1±7.3 years. Only 71 patients (28.1%) maintained a favourable outcome of a sustained normal pouch. These patients were older at UC diagnosis (27.8±12.5 vs 23.0±11.4 years), had longer UC duration until surgery (13.4±9.5 vs 8.2±7.9 years), and had higher rates of referral to surgery due to nonrefractory (dysplasia/neoplasia) complications (42.3% vs 16.2%) compared with pouchitis patients. Median survival for sustained normal pouch was 10.8 years (95% CI 8.9-12.7 years), and it was longer in the nonrefractory group (20.3 vs 9.4 years for the refractory group, HR=2.37, 95% CI 1.25-3.52, P=.004).

CONCLUSIONS

Most patients with UC undergoing pouch surgery will develop pouchitis. Patients operated for nonrefractory indications have a more favourable outcome. These results may contribute to pre- and post-surgical decision-making. The findings imply that the processes determining UC severity may be similar to that causing pouchitis.

Spinal and Paraspinal Plexiform Neurofibromas in Patients with Neurofibromatosis Type 1: A Novel Scoring System for Radiological-Clinical Correlation

BACKGROUND AND PURPOSE

Neurofibromatosis type 1 is a common tumor predisposition syndrome. The aim of this study was to characterize the radiologic presentation of patients with neurofibromatosis type 1 with widespread spinal disease and to correlate it to clinical presentation and outcome.

MATERIALS AND METHODS

We conducted a historical cohort study of adult patients with neurofibromatosis type 1 with spinal involvement. Longitudinal clinical evaluation included pain and neurologic deficits. Radiologically, spinal involvement was classified according to a novel classification system, and a radiologic risk score was calculated.

RESULTS

Two hundred fifty-seven adult patients with neurofibromatosis type 1 are followed in our center. Thirty-four of these patients qualified for inclusion in this study. Three independent factors were found to be associated with increased risk for neurologic deficit: 1) bilateral tumors at the same level in the cervical region that approximated each other, 2) paraspinal tumors at the lumbar region, and 3) intradural lesions. On the basis of these factors, we calculated a combined risk score for neurologic deficits for each patient. We found a clear correlation between patient status and the calculated radiologic risk score. Patients with neurologic deficits were found to have a higher risk score (9 ± 8.3) than patients without neurologic deficits (2.5 ± 2.9, P < .05). Patients who progressed during the follow-up period had significantly higher scores at presentation than patients with stable conditions (9.9 ± 8.73 versus 3.9 ± 5.3, respectively; P < .05).

CONCLUSIONS

In this series, neurologic deficit is correlated with tumor burden and subtype. We found no direct correlation with tumor burden and pain. Our novel radiologic classification scoring system may be used to predict increased risk for neurologic morbidity.

Isotretinoin treatment of autosomal recessive congenital ichthyosis complicated by coexisting dysferlinopathy

Consanguinity is known to be associated with an increase in the prevalence of autosomal recessive disorders such as autosomal recessive congenital ichthyosis (ARCI). ARCI often responds well to retinoid treatment. We describe a patient with ARCI who improved under isotretinoin treatment. The patient subsequently developed elevated levels of serum creatinine phosphokinase (CPK), which led to the diagnosis of a second autosomal recessive disorder, dysferlinopathy, a rare myopathy characterized by muscle weakness, decreased tendon reflexes and marked elevation of CPK levels. This report demonstrates the need for physicians to remain alert to the possible coexistence of rare and mutually relevant disorders in populations with a high rate of consanguinity.

Androgen Receptor CAG Repeat Length in Relation to Phenotype Among Females with Nonclassical 21-Hydroxylase Deficiency

Nonclassical 21-hydroxylase deficiency (NC21OHD) manifests with various degrees of post natal virilization. The length of CAG repeats of the androgen receptor gene (AR) is inversely correlated to activity of the human androgen receptor (AR) and affects phenotype of several androgen-dependent disorders. The aim of the study was to investigate the associations between CAG repeat length and the phenotype of females with NC21OHD. CAG repeat length and AR inactivation were assessed in females with NC21OHD, and related to their clinical presentation. CAG repeat length and AR inactivation were assessed in 119 females with NC21OHD. Biallelic mean (BAM) of the CAG repeat length and the weighted BAM (WBAM) were related to various clinical parameters. Age at diagnosis and age of menarche positively correlated with BAM (r=0.22, p=0.02, and r=0.23, p=0.01, respectively). A shorter (<25) BAM was associated with younger age at diagnosis (14.8 vs. 21.4 years, p<0.01), at adrenarche (8.1 vs. 10.2 years, p<0.01) and gonadarche (9.9 vs. 11.2 years, p<0.01), and higher corrected height standard deviation score at diagnosis (0.77 vs. 0.15, p=0.01). Precocious pubarche and precocious puberty were more frequent in these with the shorter BAM. Results of WBAM were similar. The CAG repeat length of the AR gene contributes to the clinical diversity of the phenotype in females with NC21OHD.

[Androgen receptor polymorphism in relation to medical conditions characterized by hyper/hypoandrogenism]

An androgen receptor (AR) is a transcription factor consisting of four functional regions. The transactivation region contains a highly polymorphic area characterized by a variable number of CAG trinucleotide repeats encoding a polyglutamine tract. Several in vitro studies demonstrated a negative linear relation between the lengths of CAG repeats and relative AR transactivations. Numerous clinical studies then sought associations between the described polymorphism and clinical parameters of various medical conditions characterized by hyper/hypoandrogenism. In this article, we describe some of those interesting associations. We believe such links should be investigated in any medical condition involving androgens as a key element in its pathogenesis.

Microdeletion 15q13.3: a locus with incomplete penetrance for autism, mental retardation, and psychiatric disorders

BACKGROUND

Microdeletions within chromosome 15q13.3 are associated both with a recently recognised syndrome of mental retardation, seizures, and dysmorphic features, and with schizophrenia.

METHODS AND RESULTS

Based on routine diagnostic testing of approximately 8200 samples using array comparative genomic hybridisation, we identified 20 individuals (14 children and six parents in 12 families) with microdeletions of 15q13.3. Phenotypes in the children included developmental delay, mental retardation, or borderline IQ in most and autistic spectrum disorder (6/14), speech delay, aggressiveness, attention deficit hyperactivity disorder, and other behavioural problems. Both parents were available in seven families, and the deletion was de novo in one, inherited from an apparently normal parent in four, and inherited from a parent with learning disability and bipolar disorder in two families. Of the 14 children, six in five families were adopted, and DNA was available for only one of these 10 biological parents; the deletion was very likely inherited for one of these families with two affected children. Among the unavailable parents, two mothers were described as having mental retardation, another mother as having "mental illness", and one father as having schizophrenia. We hypothesise that some of the unavailable parents have the deletion.

CONCLUSIONS

The occurrence of increased adoption, frequent autism, bipolar disorder, and lack of penetrance are noteworthy findings in individuals with deletion 15q13.3. A high rate of adoption may be related to the presence of the deletion in biological parents. Unconfirmed histories of antisocial behaviours in unavailable biological parents raise the concern that future research may show that deletion 15q13.3 is associated with such behaviours.

Dominant versus recessive traits conveyed by allelic mutations - to what extent is nonsense-mediated decay involved?

Mutations in ROR2, encoding a receptor tyrosine kinase, can cause autosomal recessive Robinow syndrome (RRS), a severe skeletal dysplasia with limb shortening, brachydactyly, and a dysmorphic facial appearance. Other mutations in ROR2 result in the autosomal dominant disease, brachydactyly type B (BDB1). No functional mechanisms have been delineated to effectively explain the association between mutations and different modes of inheritance causing different phenotypes. BDB1-causing mutations in ROR2 result from heterozygous premature termination codons (PTCs) in downstream exons and the conveyed phenotype segregates as an autosomal dominant trait, whereas heterozygous missense mutations and PTCs in upstream exons result in carrier status for RRS. Given that the distribution of PTC mutations revealed a correlation between the phenotype and the mode of inheritance conveyed, we investigated the potential role for the nonsense-mediated decay (NMD) pathway in the abrogation of possible aberrant effects of selected mutant alleles. Our experiments show that triggering or escaping NMD may cause different phenotypes with a distinct mode of inheritance. We generalize these findings to other disease-associated genes by examining PTC mutation distribution correlation with conveyed phenotype and inheritance patterns. Indeed, NMD may explain distinct phenotypes and different inheritance patterns conveyed by allelic truncating mutations enabling better genotype-phenotype correlations in several other disorders.

Mode of delivery and neonatal hematocrit

The objective of this paper is to test the hypothesis that the 2-h hematocrit (HCT) is lower in infants born by cesarean section (CS) than in infants born vaginally and that the postnatal rise of HCT is lower in infants born by CS than in infants delivered vaginally. We prospectively studied 31 infants delivered by elective CS, 21 infants delivered by CS because of arrest of descent and 30 vaginally delivered (VD) infants. All pregnancies were term, uncomplicated in nonsmoking mothers. Apgar scores were > 7 at 1 and 5 min. In all infants umbilical cord was clamped early. Umbilical vein and 2-h peripheral venous micro-HCT were measured by centrifugation. Cord-blood HCT, 2-h HCT, and rise in HCT were similar in the two CS groups and significantly lower than in the VD group. In multiple regression, gestational age, Apgar score, or the presence or not of labor did not influence cord-blood HCT, 2-h HCT, or the rise in HCT. Infants born by CS have lower HCT than infants born vaginally. Prediction of 2-h HCT from cord-blood HCT must take into account the mode of delivery.