Missed opportunities for ovarian salvage in children: an 8-year review of surgically managed ovarian lesions at a tertiary pediatric surgery centre.

INTRODUCTION: The aetiology and management of ovarian pathology in children differs between antenatal and postnatal lesions. However, all lesions may present acutely due to adnexal torsion. In this setting, opportunities to preserve fertility with ovary-sparing surgery (OSS) may be missed. Some studies suggest that pediatric and adolescent gynaecology (PAG) input in care is associated with OSS. METHODS: A retrospective cohort study of children undergoing surgery for ovarian pathology at a tertiary pediatric surgery centre over an 8-year period (2011-2018). Patient factors, lesion characteristics and PAG involvement were examined for association with OSS using multivariate logistic regression. RESULTS: Thirty-five patients with ovarian pathology managed surgically were included. Ten were infants with lesions detected antenatally; all were managed by pediatric surgeons (PS) alone at median age 2 weeks (1 day-25 weeks). Twenty-five patients presented postnatally at median age 11 (0.75-15) years. In total, there were 16 cases of adnexal torsion, each managed primarily by PS. Twelve underwent oophorectomy and six (50%) of these cases had viable ovarian tissue on histology. Furthermore, two infants with large simple cysts were similarly managed by unnecessary oophorectomy based on histology. Overall rate of OSS was 46% and PAG involvement was the only factor associated with ovarian salvage. CONCLUSION: Differences in surgical management between PAGs and PS may be attributable to the different patient populations they serve. We recommend improving the knowledge of PS trainees in OSS approaches for adnexal torsion and large benign lesions.

PERCUTANEOUS BALLOON COMPRESSION OF GASSERIAN GANGLION FOR THE TREATMENT OF TRIGEMINAL NEURALGIA: AN EXPERIENCE FROM INDIA.

Trigeminal neuralgia (TN) is characterized by unilateral, lancinating, paroxysmal pain in the dermatomal distribution area of trigeminal nerve. Percutaneous balloon compression (PBC) of Gasserian ganglion is an effective, comparatively cheaper and simple therapeutic modality for treatment of TN. Compression secondary to PBC selectively injures the large myelinated A-alfa (afferent) fibers that mediate light touch and does not affect A-delta and C-fibres, which carry pain sensation. Balloon compression reduces the sensory neuronal input, thus turning off the trigger to the neuropathic trigeminal pain. In this current case series, we are sharing our experience with PBC of Gasserian Ganglion for the treatment of idiopathic TN in our patients at an academic university-based medical institution in India. During the period of August 2012 to October 2013, a total of twelve PBCs of Gasserian Ganglion were performed in eleven patients suffering from idiopathic TN. There were nine female patients and two male patients with the age range of 35-70 years (median age: 54 years). In all patients cannulation of foramen ovale was done successfully in the first attempt. In eight out of eleven (72.7%) patients ideal 'Pear-shaped' balloon visualization could be achieved. In the remaining three patients (27.3%), inflated balloon was 'Bullet-shaped'. In one patient final placement of Fogarty balloon was not satisfactory and it ruptured during inflation. This case was deferred for one week when it was completed successfully with 'Pear-shaped' balloon inflation. During the follow up period of 1-13 months, there have been no recurrences of TN. Eight out of eleven patients (72.7%) are completely off medicines (carbamazepine and baclofen) and other two patients are stable on very low doses of carbamazepine. All patients have reported marked improvement in quality of life. This case series shows that percutaneous balloon compression is a useful minimally invasive intervention for the treatment of trigeminal neuralgia.

Epidemiological, clinical and biomarker profile of pediatric patients infected with COVID-19.

BACKGROUND: Given the limited and diverse nature of published literature related to COVID-19 in pediatrics, it is imperative to provide evidence-based summary of disease characteristics for guiding policy decisions. We aim to provide comprehensive overview of epidemiological, clinical and biomarker profile of COVID-19 infection in pediatric population. METHODS: For this umbrella review, published systematic reviews from PubMed and pre-print databases were screened. Literature search was conducted from December 2019 to April 2021. Details of clinical, radiological and laboratory features were collected from each review. Qualitative observations were synthesized and pooled prevalence of mortality and asymptomatic cases were assessed using meta-analysis. RESULTS: Evidence synthesis of 38 systematic reviews included total 1145 studies and 334 398 children and adolescents. Review revealed that COVID-19 is relatively milder with better prognosis in pediatrics. However, patients with comorbidity are at higher risk. Meta-analysis of reviews showed that 21.17% (95% CI: 17.818-24.729) of the patients were asymptomatic and mortality rate was 0.12% (95% CI: 0.0356-0.246). Though there was no publication bias, significant heterogeneity was observed. Fever (48-64%) and cough (35-55.9%) were common symptoms, affecting almost every alternate patient. Ground-glass opacities (prevalence range: 27.4-61.5%) was most frequent radiographic observation. Rise in C-reactive protein, lactate dehydrogenase and D-dimer ranged from 14% to 54%, 12.2-50% and 0.3-67%, respectively. Some of the included reviews (44.7%-AMSTAR; 13.2%-GRADE) were of lower quality. CONCLUSION: Current umbrella review provides most updated information regarding characteristics of COVID-19 infection in pediatrics and can be used to guide policy decision regarding vaccination prioritization, early screening and identification of at-risk population.

SPRED1 mutations (Legius syndrome): another clinically useful genotype for dissecting the neurofibromatosis type 1 phenotype.

OBJECTIVE: Mutations of the SPRED1 gene, one of a family of Sprouty (Spry)/Spred proteins known to "downregulate" mitogen activated protein kinase (MAPK) signalling, have been identified in patients with a mild neurofibromatosis type 1 (NF1) phenotype with pigmentary changes but no neurofibromas (Legius syndrome).To ascertain the frequency of SPRED1 mutations as a cause of this phenotype and to investigate whether other SPRED/SPRY genes may be causal, a panel of unrelated mild NF1 patients were screened for mutations of the SPRED1-3 and the SPRY1-4 genes. METHODS: 85 patients with a mild NF1 phenotype were screened for SPRED1 mutations. 44 patients negative for both NF1 and SPRED1 mutations were then screened for SPRED2-3 and SPRY1-4 mutations. Complexity analysis was applied to analyse the flanking sequences surrounding the identified SPRED1 mutations for the presence of direct and inverted repeats or symmetric sequence elements in order to infer probable mutational mechanism. RESULTS: SPRED1 mutations were identified in 6 cases; 5 were novel and included 3 nonsense (R16X, E73X, R262X), 2 frameshift (c.1048_c1049 delGG, c.149_1152del 4 bp), and a single missense mutation (V44D). Short direct or inverted repeats detected immediately adjacent to some SPRED1 mutations may have led to the formation of the microdeletions and base pair substitutions. DISCUSSION: The identification of SPRED1 gene mutation in NF1-like patients has major implications for counselling NF1 families.

Germline and somatic NF1 gene mutation spectrum in NF1-associated malignant peripheral nerve sheath tumors (MPNSTs).

About 10% of neurofibromatosis type 1 (NF1) patients develop malignant peripheral nerve sheath tumors (MPNSTs) and represent considerable patient morbidity and mortality. Elucidation of the genetic mechanisms by which inherited and acquired NF1 disease gene variants lead to MPNST development is important. A study was undertaken to identify the constitutional and somatic NF1 mutations in 34 MPNSTs from 27 NF1 patients. The NF1 germline mutations identified in 22 lymphocytes DNA from these patients included seven novel mutations and a large 1.4-Mb deletion. The NF1 germline mutation spectrum was similar to that previously identified in adult NF1 patients without MPNST. Somatic NF1 mutations were identified in tumor DNA from 31 out of 34 MPNSTs, of which 28 were large genomic deletions. The high prevalence (>90%) of such deletions in MPNST contrast with the =or<20% found in benign neurofibromas and is indicative of the involvement of different mutational mechanisms in these tumors. Coinactivation of the TP53 gene by deletion, or by point mutation along with NF1 gene inactivation, is known to exacerbate disease symptoms in NF1, therefore TP53 gene inactivation was screened. DNA from 20 tumors showed evidence for loss of heterozygosity (LOH) across the TP53 region in 11 samples, with novel TP53 point mutations in four tumors.

Congenital disseminated neurofibromatosis type 1: a clinical and molecular case report.

Neurofibromatosis type 1 (NF1) is an autosomal dominant condition with a birth incidence of 1/3,500. Around 50% of cases are due to new mutations. The NF1 gene maps to 17q11.2 and encodes neurofibromin. NF1 is a "classical" tumor suppressor gene. Congenital disseminated NF1 is rare with just two cases previously reported. We present a deceased baby with congenital disseminated NF1 in whom we performed molecular studies. A germline mutation (R461X) in exon 10a of the NF1 gene was found. A 2 bp deletion (3508delCA) in codon 1170 of exon 21 was identified in DNA derived from some tumor tissue. Loss of heterozygosity in NF1 and TP53 was observed in other tumor samples. No microsatellite instability was observed in the tumor samples. This is the first report of molecular analysis of the NF1 locus in a patient with disseminated congenital neurofibromatosis. This case had a de novo germline mutation in NF1 and three documented somatic mutations in the NF1 and TP53 genes in tumor specimens.

A large patient study confirming that facioscapulohumeral muscular dystrophy (FSHD) disease expression is almost exclusively associated with an FSHD locus located on a 4qA-defined 4qter subtelomere.

Facioscapulohumeral muscular dystrophy (FSHD), an autosomal dominant disorder, represents the third most common human muscular dystrophy. The FSHD disease locus, at chromosome 4q35, is associated with large contractions of the polymorphic repeat sequence array D4Z4. In addition to FSHD disease association with large D4Z4 deletions, a biased interaction with a specific 4qter subtelomeric sequence has been described in patients. Two distinct 4qter subtelomeres, defined as types 4qA and 4qB, have been identified and shown to be equally prevalent in the Caucasian population. In almost all 4q35-linked patients with FSHD, however, disease expression only occurs when large D4Z4 deletions are located on 4qA-defined 4qter subtelomeres. Conversely, large D4Z4 repeat contractions situated on 4qB-defined subtelomeres either are not disease-causing or exhibit a greatly reduced disease penetrance. This study was initiated to confirm this direct FSHD disease association data by measuring the frequency of type 4qA-defined and 4qB-defined subtelomeric sequences in a large cohort of 164 unrelated patients with FSHD from Turkey and the UK, all known to have large D4Z4 deletions. An almost complete association was found between large D4Z4 repeat array deletions located on 4qA-defined 4qter subtelomeres and disease expression in our large FSHD patient cohort. The observed failure of probes 4qA and 4qB to hybridise to two patient-derived DNA samples confirms the presence of an additional rare type of 4qter subtelomeric sequence in humans.

Gastric carcinoid: germline and somatic mutation of the neurofibromatosis type 1 gene.

Neurofibromatosis type 1 (NF1) is one of the most common autosomal dominantly inherited conditions. A range of complications has been described, including gastrointestinal manifestations. Gastric carcinoid tumours are associated with multiple endocrine neoplasia, atrophic gastritis and pernicious anaemia but have not been reported in NF1 in the absence of other predisposing factors. We report the occurrence and investigation of a gastric carcinoid tumour in a 23-year-old woman with previously uncomplicated NF1. Analysis of the tumour tissue revealed loss of heterozygosity at the NF1 gene locus but a normal karyotype and an absence of microsatellite instability. A germline NF1 gene nonsense mutation in exon 37 was detected by denaturing high-performance liquid chromatography and DNA sequence analysis. This is the first reported occurrence of a gastric carcinoid tumour in a patient with NF1 in the absence of other predisposing factors such as pernicious anaemia. The analyses indicate that the carcinoid arose through NF1 gene inactivation but in the absence of an inherited NF1 gene microdeletion. This case adds to the range of gastrointestinal tumours that may be encountered in patients with NF1, particularly in those who present with upper gastrointestinal haemorrhage.

Identification of novel deletion breakpoints bordered by segmental duplications in the NF1 locus using high resolution array-CGH.

BACKGROUND: Segmental duplications flanking the neurofibromatosis type 1 (NF1) gene locus on 17q11 mediate most gene deletions in NF1 patients. However, the large size of the gene and the complexity of the locus architecture pose difficulties in deletion analysis. We report the construction and application of the first NF1 locus specific microarray, covering 2.24 Mb of 17q11, using a non-redundant approach for array design. The average resolution of analysis for the array is approximately 12 kb per measurement point with an increased average resolution of 6.4 kb for the NF1 gene. METHODS: We performed a comprehensive array-CGH analysis of 161 NF1 derived samples and identified heterozygous deletions of various sizes in 39 cases. The typical deletion was identified in 26 cases, whereas 13 samples showed atypical deletion profiles. RESULTS: The size of the atypical deletions, contained within the segment covered by the array, ranged from 6 kb to 1.6 Mb and their breakpoints could be accurately determined. Moreover, 10 atypical deletions were observed to share a common breakpoint either on the proximal or distal end of the deletion. The deletions identified by array-CGH were independently confirmed using multiplex ligation-dependent probe amplification. Bioinformatic analysis of the entire locus identified 33 segmental duplications. CONCLUSIONS: We show that at least one of these segmental duplications, which borders the proximal breakpoint located within the NF1 intron 1 in five atypical deletions, might represent a novel hot spot for deletions. Our array constitutes a novel and reliable tool offering significantly improved diagnostics for this common disorder.

Functional splicing assay shows a pathogenic intronic mutation in neurofibromatosis type 1 (NF1) due to intronic sequence exonization.

Genomic variations with no apparent effect ("neutral polymorphisms") may have a significant effect on splicing. The effect of this type of mutation is difficult to spot, unless a functional assay is undertaken. In our study, DNA sequencing of a patient with clinically defined neurofibromatosis type 1 (NF1) showed only a single polymorphism in intron 30 due to an A>G transition 279 nucleotides from the 3' splice site. Using a minigene splicing assay we conclusively show that this change produces a cryptic exon with a 3' SS defined by the nucleotide change and the unexpected activation of a very weak 5'SS. Further site directed mutagenesis studies aimed at identifying the signals involved in the cryptic exon inclusion were carried out. Interestingly we find that particular characteristics of the cryptic 5' SS are essential for its inclusion. Significantly an additional single nucleotide change disrupting the cryptic 5'ss consensus sequence rescues the effect of the pathogenetic mutation resulting in normal splicing.

Neurofibromatous neuropathy in neurofibromatosis 1 (NF1).

BACKGROUND: Neurofibromatosis 1 (NF1) is a common, autosomal dominant, neurocutaneous disease that is clinically and genetically distinct from the rare condition neurofibromatosis 2 (NF2). Neurofibromatous neuropathy has been regarded as a common feature of NF2, but is an unusual and unexplained complication of NF1. The clinical and histological features of the NF1 neuropathy are distinct from those encountered in NF2. We describe eight patients with a symmetrical polyneuropathy, which has been called neurofibromatous neuropathy. METHODS: Clinical assessments, laboratory investigations, neuroimaging, and neurophysiology were undertaken in eight individuals with neurofibromatous neuropathy. None were referred because of neuropathic symptoms. Two subjects underwent sural nerve biopsy and three agreed to mutational analysis. RESULTS: The patients had an indolent symmetrical predominantly sensory axonal neuropathy and unusually early development of large numbers of neurofibromas. The biopsied nerves showed diffuse neurofibromatous change and disruption of the perineurium. Two patients developed a high grade malignant peripheral nerve sheath tumour. Disease causing mutations were detected in two individuals and molecular studies did not reveal any whole gene deletions. CONCLUSIONS: Neurofibromatous neuropathy occurred in 1.3% of 600 patients with NF1. Its cause may be a diffuse neuropathic process arising from inappropriate signalling between Schwann cells, fibroblasts, and perineurial cells.

Autosomal dominant inheritance of autoantibodies to thyroid peroxidase and thyroglobulin--studies in families not selected for autoimmune thyroid disease.

Recently the tendency to produce autoantibodies to thyroid peroxidase (TPO Ab) and thyroglobulin (Tg Ab) was shown to be inherited as an autosomal dominant characteristic in women but not in men. Because of potential bias in this study which was carried out in families with autoimmune thyroid disease (AITD), the inheritance of thyroid autoantibodies has been evaluated in 49 families unselected for autoimmune thyroid disease. Among these families (24 with facioscapulohumeral disease, 10 with Friedreich's ataxia, and 15 with schizophrenia) the prevalences of TPO Ab and Tg Ab were 27.8% and 26.7%, respectively, in women and 9.2% and 11.7%, respectively, in men. In 40 families where one or more individual had TPO Ab and/or Tg Ab, segregation analysis showed that the tendency to make antibodies was consistent with a Mendelian dominant trait in women but not in men. In young women, however, the prevalence of both TPO Ab and Tg Ab increased with age, rising from 14% and 10%, respectively, at age 15-24 to 35% and 40% at age 35-44. As this is inconsistent with a simple dominant hypothesis, a further segregation analysis by age was carried out in the families unselected for thyroid disease together with 16 pedigrees with AITD previously studied and two additional large AITD families. The results of the combined analysis provided strong support for the hypothesis of dominant inheritance but also showed significant reduction in gene expression among women aged 15-24 yr.

Estimation of the mutation frequencies in Charcot-Marie-Tooth disease type 1 and hereditary neuropathy with liability to pressure palsies: a European collaborative study.

A European collaboration on Charcot-Marie-Tooth type 1 (CMT1) disease and hereditary neuropathy with liability to pressure palsies (HNPP) was established to estimate the duplication and deletion frequency, respectively, on chromosome 17p11.2 and to make an inventory of mutations in the myelin genes, peripheral myelin protein 22 (PMP22), myelin protein zero (MPZ) and connexin 32 (Cx32) located on chromosomes 17p11.2, 1q21-q23 and Xq13.1, respectively. In 70.7% of 819 unrelated CMT1 patients, the 17p11.2 duplication was present. In 84.0% of 156 unrelated HNPP patients, the 17p11.2 deletion was present. In the nonduplicated CMT1 patients, several different mutations were identified in the myelin genes PMP22, MPZ and Cx32.

Molecular genetics of facioscapulohumeral muscular dystrophy (FSHD).

Facioscapulohumeral muscular dystrophy (FSHD; MIM 158900), is an autosomal dominant neuromuscular disorder. The disease is characterized by the weakness of the muscles of the face, upper-arm and shoulder girdle. The gene for FSHD has been mapped to 4q35 (FSHD1A) and is closely linked to D4F1O4S1, which detects two highly polymorphic loci (located at 4q35 and 10q26), with restriction enzyme EcoRI. The polymorphic EcoRI fragment detected with D4F1O4S1 is composed almost entirely of D4Z4 (3.3 kb) tandem repeats. In FSHD patients a deletion of the integral number of D4Z4 repeats generates a fragment which is usually smaller than 35 kb, whereas in normal controls, the size usually ranges from 50 to 300 kb. These 'small' EcoRI fragments segregate with FSHD in families but appear as de novo deletions in the majority of sporadic cases. Each 3.3 kb repeat contains two homeobox domains neither of which has yet been proven to encode a protein. D4Z4 is located adjacent to the 4q telomere and cross hybridizes to several different regions of the genome. Although D4Z4 probably does not encode a protein with any direct association to FSHD, a clear correlation has been shown between the deletion size at this locus and the age at onset of the disease in FSHD patients. In approximately 5-10% of FSHD families the disease locus is unlinked to 4q35 (locus designated FSHD1B), however, none of the non 4q35 loci for FSHD have yet been chromosomally located. Thus so far, only one gene, FRG1 (FSHD region gene 1) has been identified from the FSHD candidate region on 4q35. The apparent low level of expressed sequences from within this region, the integral deletions of D4Z4 repeats observed in FSHD patients and the close proximity of these repeats to the 4q telomere, all suggest that the disease may be the result of position effect variegation. To date, the molecular diagnosis of FSHD with D4F104S1 has been most secure in those families which are linked to other 4q35 markers. Recent studies based on the distinction of 4q35 fragments from those from 10q26 will facilitate molecular diagnosis. The pathophysiology and biochemical defect in FSHD still remains to be elucidated. The identification of the FSHD gene and characterization of the gene product will not only potentiate accurate diagnosis but may also unravel the complexities of the 4q35 FSHD region.

A scapular onset muscular dystrophy without facial involvement: possible allelism with facioscapulohumeral muscular dystrophy.

A dominantly inherited muscular dystrophy with onset in the shoulder girdle and later progression to the lower limbs is described. The disorder was clinically distinguishable from known facioscapulohumeral, scapulohumeral and limb girdle syndromes. A 38 kb allele detected by probe p13E-11 (D4F104S1) segregated with the disease. Linkage analysis gave a maximum lod score of z = 1.61 at theta = 0.01 with the 4q35 markers D4S184 (affected only analysis z = 1.20 at theta = 0.01) suggesting probable allelism with facioscapulohumeral muscular dystrophy.

Two single base polymorphisms in introns 41 and 16 of the NF1 gene.

We have characterized two intragenic polymorphisms in the neurofibromatosis type 1 (NF1) gene by direct sequencing of PCR products. The variants for these polymorphisms were initially detected on Hydrolink gels. One of the polymorphisms involves a G to A transition in intron 41 at the 28th base upstream of exon 42 with an observed 'G'/'A' heterozygosity of 0.42. The other polymorphism is a T to C transition in intron 16 at the 16th base upstream of exon 17 with an observed 'T'/'C' heterozygosity of 0.09. In combination with other documented polymorphisms in the NF1 gene, these variants should assist in genetic analysis of NF1 families.

Characterization of six mutations in exon 37 of neurofibromatosis type 1 gene.

Neurofibromatosis type 1 (NF1) is one of the most common inherited disorders, with an incidence of 1 in 3,000. We screened a total of 320 unrelated NF1 patients for mutations in exon 37 of the NF1 gene. Six independent mutations were identified, of which three are novel, and these include a recurrent nonsense mutation identified in 2 unrelated patients at codon 2281 (G2281X), a 1-bp insertion (6791 ins A) resulting in a change of TAG (tyrosine) to a TAA (stop codon), and a 3-bp deletion (6839 del TAC) which generated a frameshift. Another recurrent nonsense mutation, Y2264X, which was detected in 2 unrelated patients in this study, was also previously reported in 2 NF1 individuals. All the mutations were identified within a contiguous 49-bp sequence. Further studies are warranted to support the notion that this region of the gene contains highly mutable sequences.

Towards the finer mapping of facioscapulohumeral muscular dystrophy at 4q35: construction of a laser microdissection library.

Facioscapulohumeral muscular dystrophy (FSHD) is an autosomal-dominant disorder which has been mapped to the 4q35 region. In order to saturate this distal 4q region with DNA markers, a laser-based chromosomal microdissection and microcloning procedure was used to construct a genomic library from the distal 20% of chromosome 4, derived from a single human metaphase spread. Of the 100 microclones analyzed from this library, 94 clones contained inserts sized from 80-800 bp, with an average size of 340 bp. Less than 20% of these clones hybridized to human repeat sequences. Seventy-two single-copy clones were further characterized by Southern blot hybridization against a DNA panel of somatic cell hybrids, containing various regions of chromosome 4. Forty-two clones mapped to chromosome 4, of which 8 clones mapped into the relevant 4q35 region. Twenty of these chromosome 4-specific clones were screened against "zoo-blots"; 11 clones, of which 3 mapped to 4q35, identified conserved sequences. This is the first report to describe the isolation of potential expressed sequences derived from the FSHD region. These chromosome region-specific microclones will be useful in the construction of the physical map of the region, the positional cloning of potential disease-associated genes, and the identification of additional polymorphic markers from within the distal 4q region.

Prenatal diagnosis of X-linked hypohidrotic ectodermal dysplasia by linkage analysis.

Prenatal diagnosis of X-linked hypohidrotic ectodermal dysplasia was previously performed by the direct histological analysis of fetal skin obtained by late second trimester fetoscopy. The recent gene mapping of the locus for the disorder to the region of Xq11-21.1 now permits the indirect prenatal diagnosis of the disorder by the method of linkage analysis, based on closely linked marker loci, during the first trimester of pregnancy. We report the prenatal diagnosis of a male fetus with a high probability of the disorder by a linkage analysis utilizing restriction fragment length polymorphisms at the DXS159, PGK1, and DXS72 loci, from a DNA sample obtained by a chorionic villus biopsy at 9 weeks gestation. After further counseling, the pregnancy was terminated but the diagnosis could not be confirmed by histological analysis, even though analysis of skin samples by light and electron microscopy showed lack of hair germs, primary dermal ridges, and sweat gland primordia, due to the early developmental stage of the fetus. The use of DNA-based linkage analysis now offers the opportunity for an earlier diagnosis of X-linked hypohidrotic ectodermal dysplasia by a method other than fetal skin sampling. However, families must also fully understand the present limitations of the method prior to undertaking the procedure.