Childhood pilomatricomas: Associated anomalies

Clinical and molecular characteristics of Korean patients with Kabuki syndrome

INTRODUCTION

Kabuki syndrome (KS) is a rare disorder characterized by typical facial features, skeletal anomalies, fetal fingertip pad persistence, postnatal growth retardation, and intellectual disabilities. Heterozygous variants of the KMT2D and KDM6A genes are major genetic causes of KS. This study aimed to report the clinical and genetic characteristics of KS.

METHODS

This study included 28 Korean patients (14 boys and 14 girls) with KS through molecular genetic testing, including direct Sanger sequencing, whole-exome sequencing, or whole-genome sequencing.

RESULTS

The median age at clinical diagnosis was 18.5 months (IQR 7-58 months), and the median follow-up duration was 80.5 months (IQR 48-112 months). Molecular genetic testing identified different pathogenic variants of the KMT2D (n = 23) and KDM6A (n = 3) genes, including 15 novel variants. Patients showed typical facial features (100%), such as long palpebral fissure and eversion of the lower eyelid; intellectual disability/developmental delay (96%); short stature (79%); and congenital cardiac anomalies (75%). Although 71% experienced failure to thrive in infancy, 54% of patients showed a tendency toward overweight/obesity in early childhood. Patients with KDM6A variants demonstrated severe genotype-phenotype correlation.

CONCLUSION

This study enhances the understanding of the clinical and genetic characteristics of KS.

Ultrasound features of benign paediatric lumps: radiology-pathology correlation

Ultrasonography is an appropriate first-line imaging technique for the characterisation of paediatric lumps, given its relative accessibility and absence of radiation exposure. Together with a thorough history and examination, ultrasonography can help to distinguish benign lesions from malignancy. It can also aid further characterisation of benign lesions to inform onward investigation and management. This review features the evaluation of common benign paediatric lumps together with their characteristic sonographic features, following correlation with histopathology results or clinical follow-up.

Ultrasound findings in 156 children with 169 pilomatricomas

BACKGROUND

Cutaneous lesions present a diagnostic challenge to radiologists and clinicians alike. Pilomatricoma is the second most common skin neoplasm in childhood, yet there are limited reports in the literature focusing on imaging in pediatric patients.

OBJECTIVE

To characterize the typical and atypical US features of pilomatricoma in pediatric patients and to determine the performance of the adult-based Solivetti classification for assessing pilomatricomas in children.

MATERIALS AND METHODS

We retrospectively reviewed 169 US scans of pathologically proven pilomatricomas in 156 children performed over a period of 66 months. We evaluated images for the size of the lesion, borders, morphology, content, calcification, location on the skin and Doppler characteristics.

RESULTS

Most of the pilomatricomas presented as single dermohypodermic lesions with peripheral vascularity on color Doppler interrogation. The cheek was the most common location, followed by the arm. Solivetti type 2 US pattern was the most frequent, and peripheral hypoechoic halo was only observed in this type. One child had an anetodermic pilomatricoma, and 11 children had multiple lesions.

CONCLUSION

We showed that pilomatricomas exhibit variable sonographic patterns. In our cohort, less than 50% of the lesions showed the characteristic hypoechoic rim and less than 30% of the cases presented as diffusely hyperechoic masses with posterior acoustic shadowing. Our results show that the Solvetti classification for the US assessment of pilomatricomas can be of value in children.

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.

A Novel Phenotype Combining Primary Ovarian Insufficiency Growth Retardation and Pilomatricomas With MCM8 Mutation

CONTEXT

Primary Ovarian insufficiency (POI) affects 1% of women aged <40 years and leads most often to definitive infertility with adverse health outcomes. Very recently, genes involved in deoxyribonucleic acid (DNA) repair have been shown to cause POI.

OBJECTIVE

To identify the cause of a familial POI in a consanguineous Turkish family.

DESIGN

Exome sequencing was performed in the proposita and her mother. Chromosomal breaks were studied in lymphoblastoid cell lines treated with mitomycin (MMC).

SETTING AND PATIENTS

The proposita presented intrauterine and postnatal growth retardation, multiple pilomatricomas in childhood, and primary amenorrhea. She was treated with growth hormone (GH) from age 14 to 18 years.

RESULTS

We identified a novel nonsense variant in exon 9 of the minichromosome maintenance complex component 8 gene (MCM8) NM_001281522.1: c0.925C > T/p.R309* yielding either a truncated protein or nonsense-mediated messenger ribonucleic acid decay.The variant was homozygous in the daughter and heterozygous in the mother. MMC induced DNA breaks and aberrant metaphases in the patient's lymphoblastoid cells. The mother's cells had intermediate but significantly higher chromosomal breaks compared with a control.

CONCLUSION

We describe a novel phenotype of syndromic POI related to a novel truncating MCM8 variant. We show for the first time that spontaneous tumors (pilomatricomas) are associated with an MCM8 genetic defect, making the screening of this gene necessary before starting GH therapy in patients with POI with short stature, especially in a familial or consanguineous context. Appropriate familial monitoring in the long term is necessary, and fertility preservation should be considered in heterozygous siblings to avoid rapid follicular atresia.