The Kabuki (Niikawa-Kuroki) syndrome: further delineation of the phenotype in 29 non-Japanese patients

Immunological Aspects of Kabuki Syndrome: A Retrospective Multicenter Study of the Italian Primary Immunodeficiency Network (IPINet)

Kabuki Syndrome (KS) is a multisystemic genetic disorder. A portion of patients has immunological manifestations characterized by increased susceptibility to infections and autoimmunity. Aiming to describe the clinical and laboratory immunological aspects of KS, we conducted a retrospective multicenter observational study on patients with KS treated in centers affiliated to the Italian Primary Immunodeficiency Network.Thirty-nine patients were enrolled, with a median age at evaluation of 10 years (range: 3 m-21y). All individuals had organ malformations of variable severity. Congenital heart defect (CHD) was present in 19/39 patients (49%) and required surgical correction in 9/39 (23%), with associated thymectomy in 7/39 (18%). Autoimmune cytopenia occurred in 6/39 patients (15%) and was significantly correlated with thymectomy (p < 0.002), but not CHD. Individuals with cytopenia treated with mycophenolate as long-term immunomodulatory treatment (n = 4) showed complete response. Increased susceptibility to infections was observed in 22/32 patients (69%). IgG, IgA, and IgM were low in 13/29 (45%), 13/30 (43%) and 4/29 (14%) patients, respectively. Immunoglobulin substitution was required in three patients. Lymphocyte subsets were normal in all patients except for reduced naïve T-cells in 3/15 patients (20%) and reduced memory switched B-cells in 3/17 patients (18%). Elevated CD3 + TCRαβ + CD4-CD8-T-cells were present in 5/17 individuals (23%) and were correlated with hematological and overall autoimmunity (p < 0.05).In conclusion, immunological manifestations of KS in our cohort include susceptibility to infections, antibody deficiency, and autoimmunity. Autoimmune cytopenia is correlated with thymectomy and elevated CD3 + TCRαβ + CD4-CD8-T-cells, and benefits from treatment with mycophenolate.

Novel KDM6A mutation in a Chinese infant with Kabuki syndrome: A case report

BACKGROUND

Kabuki syndrome (KS) is a rare syndrome characterized by multisystem congenital anomalies and developmental disorder. KMT2D and KDM6A mutations were identified as the main causative genes in KS patients. There are few case reports and genetic analyses, especially of KDM6A gene mutation, in China.

CASE SUMMARY

This study reports a de novo KDM6A mutation in a Chinese infant with KS. A 2-month-old Chinese baby was diagnosed with KS, which manifested as hypoglycemia, congenital anal atresia at birth, feeding difficulties, hypotonia, and serious postnatal growth retardation. He died of recurrent respiratory infections at age 13 mo. DNA sequencing of his blood DNA revealed a novel KDM6A frameshift mutation (c.704_705delAG, p. N236Sfs*26) (GRCh37/hg19).

CONCLUSION

We present a Chinese KS patient with a novel KDM6A frameshift mutation (c.704_705delAG, p. N236Sfs*26) (GRCh37/hg19), broadening the mutation spectrum.

Kabuki Syndrome-Clinical Review with Molecular Aspects

Kabuki syndrome (KS) is a rare developmental disorder principally comprised of developmental delay, hypotonia and a clearly defined dysmorphism: elongation of the structures surrounding the eyes, a shortened and depressed nose, thinning of the upper lip and thickening of the lower lip, large and prominent ears, hypertrichosis and scoliosis. Other characteristics include poor physical growth, cardiac, gastrointestinal and renal anomalies as well as variable behavioral issues, including autistic features. De novo or inherited pathogenic/likely pathogenic variants in the KMT2D gene are the most common cause of KS and account for up to 75% of patients. Variants in KDM6A cause up to 5% of cases (X-linked dominant inheritance), while the etiology of about 20% of cases remains unknown. Current KS diagnostic criteria include hypotonia during infancy, developmental delay and/or intellectual disability, typical dysmorphism and confirmed pathogenic/likely pathogenic variant in KMT2D or KDM6A. Care for KS patients includes the control of physical and psychomotor development during childhood, rehabilitation and multi-specialist care. This paper reviews the current clinical knowledge, provides molecular and scientific links and sheds light on the treatment of Kabuki syndrome individuals.

Using Xenopus to analyze neurocristopathies like Kabuki syndrome

Neurocristopathies are human congenital syndromes that arise from defects in neural crest (NC) development and are typically associated with malformations of the craniofacial skeleton. Genetic analyses have been very successful in identifying pathogenic mutations, however, model organisms are required to characterize how these mutations affect embryonic development thereby leading to complex clinical conditions. The African clawed frog Xenopus laevis provides a broad range of in vivo and in vitro tools allowing for a detailed characterization of NC development. Due to the conserved nature of craniofacial morphogenesis in vertebrates, Xenopus is an efficient and versatile system to dissect the morphological and cellular phenotypes as well as the signaling events leading to NC defects. Here, we review a set of techniques and resources how Xenopus can be used as a disease model to investigate the pathogenesis of Kabuki syndrome and neurocristopathies in a wider sense.

Diagnosis and Management of Hip Dislocation in Patients with Kabuki Syndrome

Background

Kabuki syndrome is a rare genetic disorder characterized by distinct dysmorphic facial features, growth deficiency, intellectual disabilities, unusual dermatoglyphic patterns, and skeletal abnormalities. The incidence of hip dislocation in Kabuki syndrome ranges from 18% to 62%. We reviewed the outcomes of management of hip dislocations in patients with Kabuki syndrome with special attention to the diagnostic processes for hip dislocation and Kabuki syndrome.

Methods

Among 30 patients with mutation-confirmed Kabuki syndrome, we selected six patients who had hip dislocations and reviewed their medical records and plain radiographs. The modes of presentation and diagnostic processes for both hip dislocations and Kabuki syndrome were investigated. The management and treatment outcomes of hip dislocations in patients with Kabuki syndrome were evaluated.

Results

The average age of patients at the time of diagnosis of hip dislocation was 7.7 months (range, 1 week to 22 months). None of the patients were diagnosed as having Kabuki syndrome at that time. Two patients were treated with a Pavlik harness; one, with closed reduction; two, with open reduction and later pelvic and/or femoral osteotomies; and one, with open reduction combined with pelvic osteotomy. The patients were followed up for 5.8 years on average (range, 2.0 to 10.5 years). The radiologic outcome was graded as Severin IA or IB for three patients who were older than 6 years at the latest follow-up (mean age, 9.9 years; range, 7.8 to 12.4 years). In the remaining three patients younger than 6 years (mean age, 3.8 years; range, 2.7 to 5.3 years), the lateral center edge angle was more than 15°. The clinical diagnosis of Kabuki syndrome was made during follow-up after hip dislocation treatment and confirmed by mutational analysis at a mean age of 4.7 years. The mean interval between the diagnosis of hip dislocation and Kabuki syndrome was 4.0 years.

Conclusions

The management of hip dislocation by conservative or surgical method showed successful results. Awareness of Kabuki syndrome could lead to an early diagnosis of this rare disease in patients with hip dislocation and allow for early detection of other underlying conditions and multidisciplinary management.

Precocious chondrocyte differentiation disrupts skeletal growth in Kabuki syndrome mice

Kabuki syndrome 1 (KS1) is a Mendelian disorder of the epigenetic machinery caused by mutations in the gene encoding KMT2D, which methylates lysine 4 on histone H3 (H3K4). KS1 is characterized by intellectual disability, postnatal growth retardation, and distinct craniofacial dysmorphisms. A mouse model (Kmt2d+/βGeo) exhibits features of the human disorder and has provided insight into other phenotypes; however, the mechanistic basis of skeletal abnormalities and growth retardation remains elusive. Using high-resolution micro-CT, we show that Kmt2d+/βGeo mice have shortened long bones and ventral bowing of skulls. In vivo expansion of growth plates within skulls and long bones suggests disrupted endochondral ossification as a common disease mechanism. Stable chondrocyte cell lines harboring inactivating mutations in Kmt2d exhibit precocious differentiation, further supporting this mechanism. A known inducer of chondrogenesis, SOX9, and its targets show markedly increased expression in Kmt2d-/- chondrocytes. By transcriptome profiling, we identify Shox2 as a putative KMT2D target. We propose that decreased KMT2D-mediated H3K4me3 at Shox2 releases Sox9 inhibition and thereby leads to enhanced chondrogenesis, providing a potentially novel and plausible explanation for precocious chondrocyte differentiation. Our findings provide insight into the pathogenesis of growth retardation in KS1 and suggest therapeutic approaches for this and related disorders.

Exploring the cognitive phenotype of Kabuki (Niikawa-Kuroki) syndrome

BACKGROUND

Kabuki syndrome (KS) is a Mendelian disorder, characterised by short stature, facial dysmorphisms and developmental delay and/or intellectual disability. Clarification of the neurocognitive profile in KS may provide directions for education and treatment interventions for KS. Previous studies on cognitive functioning in KS are scarce and have mainly focused on the general level of intelligence. The few more extensive studies suggested weaknesses in language skills, visuoconstruction, perceptual reasoning and speed of information processing. Other relevant domains such as memory, executive functioning and social cognition have not been studied yet.

METHOD

This is the first study in which cognitive functioning within multiple domains is systematically explored in 29 participants with KS (age range: 5-48 years) and compared to both norm groups (healthy population) and an appropriate control group of 15 individuals with other genetic syndromes (age range: 6-28 years).

RESULTS

Compared to the norm groups of the cognitive test manuals, as expected, participants with KS show a weaker performance on all cognitive tests. Comparison with the more appropriate genetic control group indicates weaknesses in visuoconstruction and visual memory and no weaknesses in planning, cognitive flexibility or social cognition. Verbal memory seems to be a relative strength.

CONCLUSIONS

Individuals with KS suffer from specific weaknesses in visuoconstruction, in addition to their intellectual disability/developmental delay. These impairments in visuoconstruction plausibly result from problems in visual perceptual processing, which highlight the importance of the use of auditory cues instead of visual cues in targeted educational support and psychosocial interventions.

Molecularly confirmed Kabuki (Niikawa-Kuroki) syndrome patients demonstrate a specific cognitive profile with extensive visuospatial abnormalities

BACKGROUND

Kabuki (Niikawa-Kuroki) syndrome (KS) is caused by disease-causing variants in either of two components (KMT2D and KDM6A) of the histone methylation machinery. Nearly all individuals with KS have cognitive difficulties, and most have intellectual disability. Recent studies on a mouse model of KS suggest disruption of normal adult neurogenesis in the granule cell layer of the dentate gyrus of the hippocampus. These mutant mice also demonstrate hippocampal memory defects compared with littermates, but this phenotype is rescued postnatally with agents that target the epigenetic machinery. If these findings are relevant to humans with KS, we would expect significant and disproportionate disruption of visuospatial functioning in these individuals.

METHODS

To test this hypothesis, we have compiled a battery to robustly explore visuospatial function. We prospectively recruited 22 patients with molecularly confirmed KS and 22 IQ-matched patients with intellectual disability.

RESULTS

We observed significant deficiencies in visual motor, visual perception and visual motor memory in the KS group compared with the IQ-matched group on several measures. In contrast, language function appeared to be marginally better in the KS group compared with the IQ-matched group in a sentence comprehension task.

CONCLUSIONS

Together, our data suggest specific disruption of visuospatial function, likely linked to the dentate gyrus, in individuals with KS and provide the groundwork for a novel and specific outcome measure for a clinical trial in a KS population.

Characteristics of epilepsy in patients with Kabuki syndrome with KMT2D mutations

BACKGROUND

The characteristics of epilepsy in patients with Kabuki syndrome with KMT2D mutations (KABUK1) have not yet been well documented. This is the first review to explore this.

MATERIALS & METHODS

We enrolled 14 patients with KABUK1, whose median age was 13.6years (range=4.1-21.3years). Their medical records from October 1981 to May 2016 were retrospectively analyzed.

RESULTS

Epilepsy was present in 5 (36%) patients. Four of these patients presented with nonsense mutations and one with missense mutations. None presented with brain abnormalities. Four patients presented with annual or monthly focal seizures, of which three evolved to bilateral convulsive seizures. Median onset age of focal epilepsy was 11.8years (range=9.5-12.8years). One presented with monthly myoclonic seizures from age 11.2, whose mother with no other KABUK1 features, had focal epilepsy. The cumulative incidence of epilepsy related to KABUK1 up until age 13 was 45%. Interictal electroencephalogram revealed focal paroxysmal epileptiform discharges (in frontal, central, and parietal regions) in three patients, diffuse high-voltage spike-and-waves in one patient, and normal sleep record in one patient. Myoclonic seizures were rapidly controlled by levetiracetam. In contrast, focal seizures were not controlled in the early period of antiepileptic therapy.

CONCLUSION

This long-term follow-up of patients with KABUK1 revealed a higher prevalence of epilepsy than previously reported. The age of epilepsy onset and rate of focal seizures evolving to bilateral convulsive seizures in KABUK1 were also higher than previously reported in patients with clinically diagnosed Kabuki syndrome. Although seizure outcome is reported to be favorable in Kabuki syndrome, focal seizures in patients with KABUK1 were not immediately responsive to medication.

Lower lip pits: van der woude or kabuki syndrome?

Kabuki syndrome (KS) is a multiple congenital anomaly/mental retardation syndrome with characteristic facial features. Despite more than 350 documented cases and recent correlation of MLL2 mutations as a genetic cause, its full clinical spectrum is still being defined. This report describes two patients who were initially diagnosed with Van der Woude syndrome (VWS) based on the presence of lower lip pits. However, this finding can occur with KS, albeit infrequently. For patients with lower lip pits, a thorough evaluation should be made to distinguish between VWS and KS, as there are differences in long-term prognosis.

Clinical and molecular spectrum of renal malformations in Kabuki syndrome

OBJECTIVE

To determine the frequency and types of renal malformations, and to evaluate renal function in a cohort of patients with Kabuki syndrome (KS).

STUDY DESIGN

Renal ultrasound scans and plasma creatinine measurements were collected from a French cohort of 94 patients with genotyped KS. Renal function was evaluated based on the estimated glomerular filtration rate. A genotype-phenotype study was conducted for renal and urinary tract malformations.

RESULTS

Renal malformations were present in 22% of cases, and urinary tract anomalies were present in 15%. Renal malformations were observed in 28% of the MLL2 mutation-positive group and in 0% of the MLL2 mutation-negative group (P = .015). No correlation was found between the presence or absence of renal or urinary tract malformations and the location or type of MLL2 mutation. Renal function was normal except for 1 patient with a MLL2 mutation diagnosed in the first days of life and severe renal disease due to unilateral renal agenesia and controlateral severe hypoplasia that progressed to the terminal stage at age 2 years.

CONCLUSION

Our study emphasizes the need for ultrasound and renal function screening in children diagnosed with KS.

Surgical treatment of hip dislocation in Kabuki syndrome: use of incomplete periacetabular osteotomy for posterior acetabular wall deficiency

PURPOSE

Kabuki syndrome is characterized by distinctive facial features, skeletal anomalies, persisting fingertip pads with dermatoglyphic abnormalities, postnatal growth deficiency and mental retardation. This report reviews our results in the operative treatment of hip dislocations in patients with Kabuki syndrome.

METHODS

Between 2001 and 2009, seven dislocated hips (three unilateral and two bilateral hips) in five patients (all girls) were operatively treated at our institution. The operative treatment consists of open reduction, femoral derotation varus osteotomy, pelvic osteotomy (Salter in one and incomplete periacetabular osteotomy in six hips) and capsular plication. The age of the patients at the time of surgery ranged from 2.4 to 5.7 years, with an average of 3.6 years.

RESULTS

The follow-up postoperative period ranged from 3.2 to 6.3 years, with an average of 5.0 years. At the final follow-up, all patients reported no click and no pain, and showed well-contained hips by radiographs. All seven hips were graded as Severin class I-II. One patient presented as having habitual dislocation of the hip 4.4 years after surgery. Computed tomographic (CT) scans revealed posterior acetabular wall deficiency, which was not corrected by the anterolaterally directed Salter osteotomy. The incomplete periacetabular osteotomy provided sufficient posterolateral coverage of the acetabulum.

CONCLUSION

Operative treatment combining open reduction, femoral derotation varus and incomplete periacetabular osteotomies, and capsular plication provided successful results in patients with Kabuki syndrome who had the characteristics of hip instability such as ligamentous laxity, muscular hypotonia and posterior acetabular wall deficiency.

[Kabuki syndrome]

INTRODUCTION

Kabuki syndrome (OMIM: #147 920) presents as large palpebral fissures with eversion of the lateral third of the lower eyelids, depressed nasal bridge, arched eyebrows, dysplastic ears and in most cases, with mental retardation. Patients have minor and major abnormalities in different systems. Its genetic basis is heterogeneous, but recently has been associated with mutations in gen MLL2.

CASE REPORTS

We present two patients with clinical features compatibles with the syndrome, mainly: large palpebral fissures with eversion of the lateral third of the lower eyelids, depressed nasal bridge, arched eyebrows, flat nose, persistent fingertip pads, cardiopathies and renal anomalies.

COMMENTARY

The diagnosis of this condition is clinical. The characteristics in the cases are compared with the patients reported in the literature. The importance of early diagnosis is to provide preventive management and an appropriate genetic counseling for the family.

Altered mTOR signaling and enhanced CYFIP2 expression levels in subjects with fragile X syndrome

Fragile X syndrome (FXS) is the most common form of inherited intellectual disability and autism. The protein (FMRP) encoded by the fragile X mental retardation gene (FMR1), is an RNA-binding protein linked to translational control. Recently, in the Fmr1 knockout mouse model of FXS, dysregulated translation initiation signaling was observed. To investigate whether an altered signaling was also a feature of subjects with FXS compared to typical developing controls, we isolated total RNA and translational control proteins from lymphocytes of subjects from both groups (38 FXS and 14 TD). Although we did not observe any difference in the expression level of messenger RNAs (mRNAs) for translational initiation control proteins isolated from participant with FXS, we found increased phosphorylation of the mammalian target of rapamycin (mTOR) substrate, p70 ribosomal subunit 6 kinase1 (S6K1) and of the mTOR regulator, the serine/threonine protein kinase (Akt), in their protein lysates. In addition, we observed increased phosphorylation of the cap binding protein eukaryotic initiation factor 4E (eIF4E) suggesting that protein synthesis is upregulated in FXS. Similar to the findings in lymphocytes, we observed increased phosphorylation of S6K1 in brain tissue from patients with FXS (n = 4) compared to normal age-matched controls (n = 4). Finally, we detected increased expression of the cytoplasmic FMR1-interacting protein 2 (CYFIP2), a known FMRP interactor. This data verify and extend previous findings using lymphocytes for studies of neuropsychiatric disorders and provide evidence that misregulation of mTOR signaling observed in the FXS mouse model also occurs in human FXS and may provide useful biomarkers for designing targeted treatments in FXS.

Craniofacial and dental features in kabuki syndrome patients

Objective : To describe oral manifestations in Brazilian individuals with Kabuki syndrome, a multiple congenital anomaly/mental retardation syndrome. Study Design : A total of 16 Kabuki syndrome individuals, aged between 8 to 24 years and of both sexes, were referred by the Department of Clinical Genetics for oral treatment and follow-up to the Oral Care Center for Inherited Diseases, University Hospital of Brasília, Brasília, Brazil. Each individual underwent complete physical examination, as well as intraoral and radiographic examinations. Results : Craniofacial and dental alterations were observed in all Kabuki syndrome patients examined. In addition, atypical shape of the molars' crowns, occlusal convergence of the premolars' crowns, and root dilaceration were also observed. Enamel diffuse opacities were observed in permanent dentition (n  =  10). Conclusion : A great clinical heterogeneity was observed in Kabuki syndrome individuals in line with previous studies in the literature. Further clinical and molecular studies are necessary in order to better understand the presence of dental anomalies in this syndrome.

Cleft hand in Kabuki make-up syndrome: case report

Kabuki make-up syndrome (KMS) is a multiple malformation/mental retardation syndrome that was first described in Japan but is now reported in many other ethnic groups. Kabuki make-up syndrome is characterized by multiple congenital abnormalities: craniofacial, skeletal, and dermatoglyphic abnormalities; mental retardation; and short stature. Common hand anomalies associated with KMS include persistent fingertip pad, brachydactyly, clinodactyly, and lax joints. We report a patient with KMS who presented with cleft hand, a feature that has not yet been described in KMS, and describe the potential genetic cause.

A Japanese patient with Kabuki syndrome and unilateral perisylvian cortical dysplasia

Kabuki syndrome is a rare multiple anomaly syndrome characterized by a peculiar face, skeletal and dermatoglyphic anomalies, postnatal growth retardation and mental retardation. We report a case of Kabuki syndrome with unilateral perisylvian cortical dysplasia. This two-year old boy was referred to our hospital at 3-months of age for his growth retardation and muscle hypotonia. Because of his peculiar face, brachydactyly V and fingertip pad, we diagnosed him as having Kabuki syndrome. His MRI revealed cortical dysplasia along the left sylvian fissure. However, neither epileptic seizures nor epileptiform discharges on electroencephalogram were observed. Cortical dysplasia is a relatively rare brain malformation among the central nervous system anomalies accompanying with this syndrome. We have to take into consideration the likely onset of epilepsy in this patient because it is one of the most frequent neurological consequences of cortical dysplasia.

Seizures and EEG pattern in Kabuki syndrome

PURPOSE

Kabuki syndrome (KS) is a rare dysmorphogenic disorder that is characterized by multiple congenital abnormalities with central nervous system involvement. The diagnosis is clinical and a variable degree of mental retardation is always present. Epilepsy is frequently reported, but a typical electroclinical pattern has not been described. We describe the electroclinical features of eight KS non-Japanese patients with epilepsy.

METHODS

We analysed seizure characteristics and pattern EEG and clinical outcomes in eight KS patients.

RESULTS

All patients presented with focal seizures. A frontal epileptic status was present in two cases. We highlighted the fact that, during evolution, seven patients shared the same interictal EEG pattern, which was characterized by isolated or repetitive biphasic spikes or sharp waves, followed by a slow wave of medium and high voltage, predominantly localised in the fronto-central regions. The natural course of seizures is favourable.

CONCLUSIONS

Our results showed a peculiar homogeneous electroclinical pattern in KS, characterized by focal seizures more frequently origin in fronto-central area which demonstrated that seizures are mostly focal in type and that a fronto-central origin is more frequently evident.

The C20orf133 gene is disrupted in a patient with Kabuki syndrome

Kabuki syndrome (KS) is a rare, congenital mental retardation syndrome. The aetiology of KS remains unknown. Four carefully selected patients with KS were screened for chromosomal imbalances using array comparative genomic hybridisation at 1 Mb resolution. In one patient, a 250 kb de novo microdeletion at 20p12.1 was detected, deleting exon 5 of C20orf133. The function of this gene is unknown. In situ hybridisation with the mouse orthologue of C20orf133 showed expression mainly in brain. The de novo nature of the deletion, the expression data and the fact that C20orf133 carries a macro domain, suggesting a role for the gene in chromatin biology, make the gene a likely candidate to cause the phenotype in this patient with KS. Both the finding of different of chromosomal rearrangements in patients with KS features and the absence of C20orf133 mutations in 19 additional patients with KS suggest that KS is genetically heterogeneous.

Dental evaluation of Kabuki syndrome patients

Kabuki syndrome is a genetic disorder of unknown etiology characterized by mental retardation, growth deficiency, and peculiar face (i.e., long palpebral fissures, eversion of the lateral third of the lower eyelids, prominent ears, and broad and depressed nasal tip). Oral manifestations commonly observed in Kabuki syndrome may comprise cleft lip/palate, bifid tongue and uvula, malocclusion, and dental abnormalities. We evaluated the dental findings of eight patients with Kabuki syndrome. One presented cleft palate; three presented caries; and seven had missing teeth, with the upper lateral incisors and inferior central incisors being the most commonly absent. All missing teeth were permanent, and there was no alteration of dental chronology or morphology. Because most patients had mixed dentition, the presence or absence of primary teeth was assessed through the parents' reports. One patient presented an absent upper canine, which had not been reported previously in the literature. Dental findings may be helpful for clinical diagnosis, or they may be an additional finding to substantiate the diagnosis of Kabuki syndrome in children with mild phenotype.

A small and active ring X chromosome in a female with features of Kabuki syndrome

A ring X chromosome is found in about 6% of patients with Turner syndrome (TS), often with mosaicism for a 45,X cell line. Patients with this karyotype are reported to have a higher incidence of a more severe phenotype including mental retardation. In fact, some studies have shown a correlation between this severity and the presence or absence of an intact and functional X inactivation center (XIST). However, the phenotype of the individuals with r(X) cannot be entirely defined in terms of their X-inactivation patterns. Nevertheless, a small group of these patients have been described to manifest clinical features reminiscent of the Kabuki syndrome. Here we present a female patient with clinical features resembling Kabuki syndrome and a mos 45,X/46,X,r(X) karyotype. Methylation analyses of polymorphic alleles of the androgen receptor gene showed that both alleles were unmethylated suggesting an active ring chromosome. A specific X chromosome array CGH was performed estimating the size of the ring to be 17 Mb, lacking the XIST gene, and including some genes with possible implications in the phenotype of the patient.

A case of Kabuki syndrome presenting West syndrome

A 6-month-old girl visited our hospital because of mental retardation, regression, and tonic spasms in cluster. We diagnosed her as West syndrome because of hypsarrhythmia on electroencephalogram (EEG) and tonic spasms in cluster. We also diagnosed her as Kabuki syndrome because of multiple malformations, especially a characteristic peculiar face (resembling a Kabuki actor). She was first administered clonazepam, but this was not effective. Later, she was administered vitamin B6, valproic acid, and zonisamide. Zonisamide was effective, and her tonic spasms were suppressed. Her EEG at 9 months of age showed the disappearance of hypsarrhythmia and sporadic spike and wave complexes on P3, P4, O1, and O2. At 2 years of age, she still showed mental retardation, despite the good control of West syndrome. To the best of our knowledge, Kabuki syndrome presenting West syndrome has been reported in only one previous case. We must pay attention to the occurrence of West syndrome in Kabuki syndrome.

The C20orf133 gene is disrupted in a patient with Kabuki syndrome

BACKGROUND

Kabuki syndrome (KS) is a rare, clinically recognisable, congenital mental retardation syndrome. The aetiology of KS remains unknown.

METHODS

Four carefully selected patients with KS were screened for chromosomal imbalances using array comparative genomic hybridisation at 1 Mb resolution.

RESULTS

In one patient, a 250 kb de novo microdeletion at 20p12.1 was detected, deleting exon 5 of C20orf133. The function of this gene is unknown. In situ hybridisation with the mouse orthologue of C20orf133 showed expression mainly in brain, but also in kidney, eye, inner ear, ganglia of the peripheral nervous system and lung.

CONCLUSION

The de novo nature of the deletion, the expression data and the fact that C20orf133 carries a macro domain, suggesting a role for the gene in chromatin biology, make the gene a likely candidate to cause the phenotype in this patient with KS. Both the finding of different of chromosomal rearrangements in patients with KS features and the absence of C20orf133 mutations in 19 additional patients with KS suggest that KS is genetically heterogeneous.

Kabuki make-up (Niikawa-Kuroki) syndrome: dental and craniofacial findings in a Brazilian child

This article reports the case of a Brazilian child diagnosed with Kabuki make-up syndrome (KMS), addressing the clinical features observed, with emphasis on the disease-specific oral and craniofacial manifestations. The patient had the distinctive KMS craniofacial appearance, mild delayed mental development, fingers with prominent fingertip pads and visual deficit. The dental findings included fusion of the left mandibular incisors (central and lateral), gemination of the right mandibular central incisor and congenital agenesis of the right mandibular lateral incisor, in the primary dentition, as well as absence of both permanent mandibular lateral incisors. Fusion and gemination have not been previously referred to as typical dental features in KMS. The detection of unique dental findings, such as missing teeth and dental anomalies of form in the primary dentition by means of clinical and radiographic examinations, might consist of a helpful diagnosis parameter in identifying children who may have milder forms of Kabuki syndrome.

Kabuki syndrome: a review

Kabuki syndrome (KS) (Kabuki make-up syndrome, Niikawa-Kuroki syndrome) is a multiple malformation/mental retardation syndrome that was described initially in Japan but is now known to occur in many other ethnic groups. It is characterized by distinctive facial features (eversion of the lower lateral eyelid, arched eyebrows with the lateral one-third dispersed or sparse, depressed nasal tip, and prominent ears), skeletal anomalies, dermatoglyphic abnormalities, short stature, and mental retardation. A number of other manifestations involving other organ systems can aid in the diagnosis and management of KS. This review will focus on the diagnostic criteria, the common and rare features of KS by organ system, and the possible etiology of this interesting condition.

Further delineation of Kabuki syndrome in 48 well-defined new individuals

Kabuki syndrome is a multiple congenital anomaly/mental retardation syndrome. This study of Kabuki syndrome had two objectives. The first was to further describe the syndrome features. In order to do so, clinical geneticists were asked to submit cases-providing clinical photographs and completing a phenotype questionnaire for individuals in whom they felt the diagnosis of Kabuki syndrome was secure. All submitted cases were reviewed by four diagnosticians familiar with Kabuki syndrome. The diagnosis was agreed upon in 48 previously unpublished individuals. Our data on these 48 individuals show that Kabuki syndrome variably affects the development and function of many organ systems. The second objective of the study was to explore possible etiological clues found in our data and from review of the literature. We discuss advanced paternal age, cytogenetic abnormalities, and familial cases, and explore syndromes with potentially informative overlapping features. We find support for a genetic etiology, with a probable autosomal dominant mode of inheritance, and speculate that there is involvement of the interferon regulatory factor 6 (IRF6) gene pathway. Very recently, a microduplication of 8p has been described in multiple affected individuals, the proportion of individuals with the duplication is yet to be determined.

Niikawa-Kuroki-Syndrom

Niikawa-Kuroki syndrome (Kabuki make-up syndrome) is a congenital disorder with characteristic facial features and possibly anomalies of the skeletal system and internal organs. There is an increasing number of reports of patients with combined hearing impairment, inner ear deformities or sensorineural hearing impairment. In addition, the patients often suffer from therapy-resistant chronic otitis media. In addition to multiple cardiac and renal deformities, our 3 year old patient has a hearing impairment due to chronic otitis media with chronic otorrhea, and requires a hearing aid. A high-definition CT scan of the petrosal bone revealed, for the first time in a patient with Niikawa-Kuroki syndrome, a large vestibular aqueduct syndrome and deformities of the vestibular system. We examine the problems involved with treating chronic otorrhea in chronic otitis media and providing patients with BTE hearing aids.

Atypical findings in Kabuki syndrome: report of 8 patients in a series of 20 and review of the literature

Kabuki syndrome (KS) is a rare multiple congenital anomaly/mental retardation syndrome with an estimated frequency of 1/32,000 in Japan. Five major criteria delineate KS namely postnatal short stature, skeletal anomalies, moderate mental retardation, dermatoglyphic anomalies, and a characteristic facial dysmorphism. Here we report on a series of 20 sporadic KS patients and we focus on some rare and atypical features that we have observed: chronic and/or severe diarrhea (4/20) including celiac disease, diaphragmatic defects (3/20), pseudarthrosis of the clavicles (2/20), vitiligo (2/20), and persistent hypoglycemia (2/20). Other occasional findings were severe autoimmune thrombopenia, cerebellar vermis atrophy, and myopathic features. Interestingly, one of our KS patients presented with a clinical overlap with CHARGE syndrome (right eye microphtalmia with optic nerve coloboma, VSD, bilateral cryptorchidism, and severe deafness). Because these features are more frequent in our series than previously described, we propose to carefully investigate these manifestations during KS patient survey in an attempt to determine their real frequency and in order to improve clinical management.

Immune abnormalities are a frequent manifestation of Kabuki syndrome

Kabuki syndrome (KS) is associated with multiple organ system involvement. Characteristic features include long palpebral fissures with everted lower lids, prominent ears, skeletal abnormalities, mental retardation, and short stature. An increased incidence of infection has been reported in KS, and a few patients have been noted to have immune defects. However, the frequency and severity of the immune deficiency has not been clearly defined. Immunologic evaluation of 19 consecutive individuals with KS was performed at The Children's Hospital of Philadelphia. Decreased IgA levels were noted in 15/19 individuals (79%), 2 of whom had undetectable levels. Eight patients (42%) also had low total IgG levels. Specific IgG subclass abnormalities were found in 6 of 13 patients evaluated. IgM levels were less frequently decreased. One patient failed to generate anti-tetanus antibodies despite immunization. This study suggests that hypogammaglobulinemia is a frequent finding in children with KS. The pattern of antibody abnormalities seen in children with KS resembles common variable immune deficiency (CVID). Due to this increased susceptibility to infection, children with KS should have immunologic evaluations at the time of diagnosis in order to reduce preventable morbidity and mortality.

Neonatal phenotype in Kabuki syndrome

The Kabuki syndrome is a well-established pattern of human malformation with readily recognizable features, however the diagnosis is rarely made in the newborn period. The purpose of this study was to determine if there exists a neonatal phenotype for this disorder. We ascertained 16 infants evaluated in the first 28 days of life by a dysmorphologist who subsequently received the diagnosis of Kabuki syndrome. The average age of initial evaluation was 8 days and the average age of diagnosis was 2 years 6 months. Based on these findings, it is suggested that the distinctive clinical phenotype seen in older patients is also evident in the newborn period.

Kabuki syndrome: Clinical data in 20 patients, literature review, and further guidelines for preventive management

The Kabuki syndrome, or Niikawa-Kuroki syndrome, is a clinically recognizable syndrome of unknown etiology. Clinical findings include early hypotonia, joint laxity, developmental delay, facial dysmorphism, persistent fetal fingertip pads, cleft palate, hypodontia, lip nodules, heart defects, and a variety of other structural defects. Behavior in general is social and pleasant. In collaboration with the Dutch Kabuki Network, we evaluated the medical data of 20 individuals diagnosed with the syndrome and compared them with data from the literature. In our literature review we used convincing cases only. Frequent findings in the oral region are under-reported in the literature: apart from the cleft palate (in about 50%), hypodontia with predominantly absence of the upper lateral incisors, and a full lower lip with symmetrical nodules, or (in a minority) lip-pits are frequent findings. Also under-reported is the presence of a thickened nuchal fold during pregnancy and hydrops in the neonatal period. Clinical recognition in the neonate is difficult. Towards early puberty acute and serious weight excess has been experienced. We suggest that a cytogenetic abnormality should be ruled out in all cases. We provide further guidelines for preventive management.

Kabuki syndrome is not caused by an 8p duplication: A cytogenetic study in 20 patients

Kabuki syndrome is characterized by a typical facial gestalt in combination with hypotonia and joint laxity, developmental delay, persistent fetal fingertip pads, and structural abnormalities mainly of the palate and the heart. Cytogenetic conditions may present with features of the syndrome. Recently, Milunsky and Huang [2003], reported an 8p duplication at chromosome 8p22-8p23.1 in 6 patients with Kabuki syndrome. We studied 20 individuals with Kabuki syndrome and were not able to confirm this finding. Kabuki syndrome remains a clinical diagnosis in the majority of cases.

Jaw-winking ptosis in a patient with Kabuki syndrome

We present a case of a child with Kabuki syndrome and jaw-winking ptosis. Kabuki syndrome is rare and consists of a constellation of findings including mental retardation, characteristic oculofacial features, and skeletal abnormalities. The association of Kabuki syndrome and jaw-winking ptosis has not been previously reported.

Long-term follow-up of three individuals with Kabuki syndrome

Long-term follow-up of three individuals with Kabuki syndrome indicates their phenotype becomes less striking as adults. It is characterized by short stature, obesity, and relatively large head. Long palpebral fissures persist, as does mild to moderate mental retardation. Independent daily living skills are achieved but a sheltered living environment is needed.

Syndromic immunodeficiencies: genetic syndromes associated with immune abnormalities

In syndromic immunodeficiencies, clinical features not directly associated with the immune defect are prominent. Patients may present with either infectious complications or extra-immune medical issues. In addition to the immunologic abnormality, a wide range of organ systems may be affected. Patients may present with disturbances in skeletal, neurologic, dermatologic, or gastrointestinal function or development. These conditions can be caused by developmental abnormalities, chromosomal aberrations, metabolic disorders, or teratogens. For a number of these conditions, recent advances have resulted in an enhanced understanding of their genetic basis. The finding of immune deficits in a number of defined syndromes with congenital anomalies suggests that an underlying genetic syndrome should be considered in those patients in whom a significant non-immune feature is present.

Acanthosis Nigricans in Kabuki Syndrome

BACKGROUND

Acanthosis nigricans has been classified in different ways. All classifications depend on the clinical picture and the association with other conditions.

OBJECTIVE

We report a case of acanthosis nigricans in a patient with Kabuki syndrome. This syndrome is characterized by five main manifestations: typical facial features, post natal growth deficiency, skeletal abnormalities, dermatoglyphic abnormalities, and mild to moderate mental retardation.

CONCLUSION

Our case may suggest that acanthosis nigricans could be associated with Kabuki syndrome.

A diagnostic conundrum: Two siblings with features overlapping the Kabuki and Malpuech syndromes. A new MCA syndrome?

We report two siblings, a boy and a girl, with a constellation of anomalies that overlap the phenotypes of Kabuki and Malpuech syndromes. Both patients had a facial appearance suggestive of Kabuki syndrome, sagittal vertebral clefts, and short fifth fingers. In addition, the girl had brachydactyly of the index finger, and the boy, cleft lip and palate, mild postnatal growth deficiency, coarctation of the aorta, ventricular septal defect, patent ductus arteriosus, and a caudal appendage. The fact that this pattern of anomaly occurred in siblings, together with the presence of sparse eyebrows medially, rather than laterally, in both patients and a caudal appendage in the boy, militates against the diagnosis of Kabuki syndrome. Furthermore, the presence of a caudal appendage in a child with cleft lip and cleft palate and renal abnormalities is suggestive of Malpuech syndrome. The normal growth pattern and psychomotor development observed in both children, however, is inconsistent with this diagnosis, although they may represent a milder end of the phenotypic spectrum for Malpuech syndrome. Alternatively, we conclude that the condition may represent a distinct multiple congenital anomaly (MCA) syndrome. The occurrence of a pattern of MCA in two siblings with phenotypically normal parents and normal cytogenetic studies, including high-resolution banding and subtelomeric probes, points toward an autosomal recessive mode of inheritance. However, germinal mosaicism and other types of non-traditional inheritance, such as a defect in genomic imprinting or uniparental disomy, should also be considered.

Favorable seizure outcome in Kabuki make-up syndrome associated with epilepsy

Kabuki make-up syndrome is a mental retardation-malformation syndrome affecting multiple organ systems, with a broad spectrum of neuromuscular dysfunction and mental ability. The incidence of seizures associated with this syndrome ranges from 10 to 40%. However, details of the seizures in this syndrome have not been adequately reported or thoroughly evaluated. In this study, we analyzed seizure characteristics and clinical outcomes in nine patients with Kabuki make-up syndrome. Four patients had generalized seizures and two patients had complex partial seizures, extended to secondary generalized seizures. West's syndrome, complex partial seizure, and atonic seizure were seen in one case each, respectively. Electroencephalograms showed focal spikes in seven cases, diffuse spike and wave burst in one case, and hypsarrhythmia in one case. Seizures were well controlled in eight cases and incompletely controlled in only one case. Together with mental retardation, epilepsy can be a primary feature of Kabuki make-up syndrome. Epilepsy associated with Kabuki make-up syndrome is mainly localization-related epilepsy with a favorable seizure outcome.

A case showing an association between type 1 diabetes mellitus and Kabuki syndrome

The case of a 31-year-old female suffering from type 1 diabetes mellitus (DM) and Kabuki syndrome is presented. The patient was diagnosed as having impaired glucose tolerance (IGT) at age 18; secondary amenorrhea occurred at age 20, following acute body weight loss. Extensive examination revealed the patient to have a slowly progressive form of type 1 DM and, based on the physical findings, including her facial features, she was diagnosed as also having congenital Kabuki syndrome. Since then, this patient has experienced several episodes of diabetic ketoacidosis, all of which were brought about by prolonged bronchial infection. Although it is perhaps reasonable at present to consider this case to represent a chance association, further clinical investigations will be carried out to clarify whether or not Kabuki syndrome and type 1 DM have any common pathogenic features.

Kabuki make-up syndrome: a review

Kabuki make-up syndrome (KMS, OMIM 147920) is an MCA/MR syndrome of unknown cause. It is characterized by a dysmorphic face, postnatal growth retardation, skeletal abnormalities, mental retardation, and unusual dermatoglyphic patterns. Approximately more than 350 cases have been reported from all over the world. Besides these five cardinal manifestations, joint laxity (74%), dental abnormalities (68%), and susceptibility to infections including recurrent otitis media (63%) were well recognized as other frequent features. A variety of visceral anomalies such as cardiovascular anomalies (42%), renal and/or urinary tract anomalies (28%), biliary atresia, diaphragmatic hernia, and anorectal anomaly were also reported. Some patients were said to have normal intelligence (16%) and normal heights, suggesting that they may have reproductive fitness to have their children. At least eight patients had lower lip pits with or without cleft palate, known as a feature of van der Woude syndrome. There have been 13 chromosomal abnormalities associated with KMS. However, no common abnormalities or breakpoints that possibly contribute to positional cloning of the putative KMS gene(s) are known. Although clinical manifestations of KMS are well established, its natural history, useful for genetic counseling, remains to be studied.

Speech characteristics in the Kabuki syndrome

Six children with Kabuki syndrome were studied to investigate speech patterns associated with the syndrome. Each child's speech was characterized with regard to articulation (types of errors and intelligibility), pitch (high or low), loudness (volume of speech), and prosody (general quality of speech that combines rate and inflection). All six children had a history of delayed speech and language acquisition and were receiving speech services. All individuals had articulation errors and abnormal oral resonance, which appeared to be due to poor oral-motor coordination and hypotonia and were not felt to be due to structural abnormalities such as velopharyngeal insufficiency, dental malocclusion, or cleft palate. An intriguing finding, noted in the two individuals followed from childhood into adolescence with serial speech evaluations, was that pitch, loudness, and prosody did not mature over time and what was age appropriate performance at younger ages became inappropriate in adolescence. This raises a challenge for speech services, as by adolescence, while articulation had improved, the pitch and loudness of these individuals' speech had not and so was noticeably different from peers. Distinctive speech characteristics with a lack of normal maturation during childhood can be added to the extensive list of clinical features associated with the Kabuki syndrome and hopefully will lead to improved speech/language treatment for individuals with this syndrome.

Hepatic fibrosis in Kabuki syndrome

Kabuki (Niikawa-Kuroki) syndrome (KS) is characterized by a distinctive face, mental retardation, growth deficiency, skeletal anomalies, dermatoglyphic abnormalities, palatal anomalies, congenital heart defects, and urogenital malformations. Congenital hepatic abnormalities have been sporadically described in patients with KS from the literature, consisting of extrahepatic biliary atresia, neonatal sclerosing cholangitis, and severe neonatal jaundice. We report here on an additional patient with a congenital abnormality of the liver consisting of hepatic fibrosis. To our knowledge, idiopathic congenital hepatic fibrosis has not been reported in KS. Thus, our observation expands the spectrum of liver malformations found in KS with the inclusion of hepatic fibrosis and supports the evidence that hepatic abnormalities may not be uncommon in KS. Clinician should be advised to search for the specific facial anomalies of KS in patients with syndromic congenital hepatic diseases, and KS should be added to the list of previously recognized multiple congenital anomaly syndromes with hepatic involvement. Due to the frequent association with congenital heart malformations, KS should be considered in the evaluation of patients with neonatal liver disease and cardiac malformation. Due to the expression patterns of Notch genes, involvement of the Notch signaling pathway in the development of heart and liver anomalies in KS should be considered.