Lacrimal Puncta Agenesis in Kabuki Syndrome

GPC4 truncating variant associated with Keipert syndrome and lacrimal punctal agenesis

Lacrimal punctal agenesis is an extremely rare condition with an unclear genetic basis. Here, we report a 3-year-old male patient harboring a hemizygous variant in glypican 4 (GPC4), which causes Keipert syndrome, who presented with complete lacrimal punctal agenesis, distinctive craniofacial features, mild developmental delay, mild intellectual disability, and autism. The craniofacial features included a prominent forehead, epicanthus, depressed and broad nasal bridge, hypoplastic columella, midface hypoplasia, tented upper lip, and low-set ears. Proband exome sequencing identified a hemizygous variant in GPC4: NM_001448.3:c.1051C > T (p.Arg351*). The GPC4 variant was inherited from his heterozygous mother; X-inactivation followed a skewed pattern in his mother. This patient demonstrated clinical features consistent with Keipert syndrome including craniofacial features, brachydactyly, broad distal phalanx, broad first toe, and mild developmental delay; however, agenesis of the lacrimal puncta has not been reported previously in Keipert syndrome. Our findings suggest that GPC4, which encodes a heparan-sulfate proteoglycan, may play an important role in lacrimal morphogenesis. Our observations also suggest that Keipert syndrome should be considered in patients with lacrimal punctal agenesis.

Punctal Atresia As a Clinical Indicator of Systemic Genetic Anomalies

BACKGROUND

Punctal atresia or agenesis (PA) is a rare congenital anomaly characterized by the absence or closure of the tear duct puncta, potentially linked to systemic genetic anomalies. The necessity of a genetic workup based solely on the presence of PA remains uncertain. This study investigates a cohort of PA patients, examining the prevalence and types of associated syndromes.

METHODS

A retrospective medical records review of all patients diagnosed with PA at the Children's Hospital of Philadelphia between 2009-2023 was conducted, analyzing medical histories and genetic testing results. Primary outcomes included the prevalence of systemic syndromes, while secondary outcomes focused on the variety of associated syndromes.

RESULTS

Forty-four patients were included, of which 31 were male (70%) with a mean ± SD age 3.3 ± 3.3 years. Overall, 87 puncta in the study cohort were affected, and 26 cases (59%) were bilateral. Systemic abnormalities or genetic syndromes were identified in 19 patients (43%), with the most common being Ectodermal Dysplasia and Down syndrome. Additional rare syndromes were demonstrated. No significant association was found between systemic abnormalities and gender, bilaterality, or the number of puncta involved.

CONCLUSIONS

A high incidence of systemic syndromes (43%) was observed in the study cohort. In individuals with PA who also exhibit extraocular disease, systemic evaluation and genetic workup should be considered. Syndromic diagnoses identified in our cohort also include: Branchio-oto-renal syndrome, 22q11.2 deletion syndrome, 1q21.1 microdeletion syndrome, NF1, monosomy 4q and trisomy 6q, which represent novel associations. The lack of correlation between PA's phenotypic severity and systemic abnormalities highlights the need to obtain a comprehensive medical history and consider a systemic workup in PA patients.

Ophthalmic manifestations in Kabuki (make-up) syndrome: A single-center pediatric cohort and systematic review of the literature

Kabuki syndrome (KS) is a genetic disorder caused by pathogenic variants in KMT2D or KDM6A, and manifesting with multi-systemic involvement, including recognizable facial features, developmental delay and multiple congenital anomalies. Ophthalmological involvement has been described in varying rates in several studies. We aimed to evaluate the prevalence and nature of ophthalmological findings in a cohort of KS patients in Israel. Medical records of all patients diagnosed with KS in our tertiary center between 2004 and 2020 were retrospectively reviewed. Data collected included physical examination findings, molecular analysis as well as comprehensive ophthalmic characteristics including visual acuity, ocular alignment and motility, ocular adnexa, anterior segments and dilated fundus exams. Finally, an updated systematic review of the literature was performed. Thirteen unrelated patients were included in the study, diagnosed at an age raging from the first months of life to 20 years. Of these, three (23%) showed significant ophthalmological abnormalities, beyond the characteristic structural findings of long palpebral fissures and lower eyelid eversion. These included bilateral posterior colobomata in the first patient; bilateral ptosis, hypermetropia, esotropia, blue sclera and anisocoria in the second; and bilateral congenital cataracts in the third. To conclude, our findings underscore the importance of a comprehensive ophthalmological evaluation as part of the routine multidisciplinary assessment of children suspected/diagnosed with KS.

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.

Updates on congenital lacrimal drainage anomalies and their association with syndromes and systemic disorders: A major review

BACKGROUND

To review and update the syndromic and non-syndromic systemic associations of congenital lacrimal drainage anomalies.

METHODS

The authors performed a PubMed search of all articles published in English on congenital lacrimal drainage anomalies (CLDA). The current review provides an update from January 2017 to August 2020 on all CLDA associated with clinical syndromes or non-syndromic systemic disorders. The update intends to appraise the readers on all papers that were published in the interim 3-year period since the publication of the previous major review by authors (1933-2016). Patients with specific syndromes or systemic disorders were then reviewed. Pertinent cross-references from each of the short-listed articles were also included. Data reviewed include syndromic descriptions, systemic details, demographics, lacrimal presentations, management, and outcomes.

RESULTS

There have been significant new updates. Eleven new syndromes have been added to the list of syndromic associations, of which three were suspects. Among the new syndromic associations, three (PHACE, Williams-Beuren, and Peter's plus syndromes) described CLDA details in depth. Several new non-syndromic systemic conditions with associated CLDA also came to light, the foremost amongst them being proboscis lateralis, diprosopus dirrhinus, cerebral palsy, and NGLY-1 related disorders. Although familial presentations have been reported, the inheritance patterns are unclear for most anomalies. Surgical challenges in these patients are distinct, and a thorough pre-operative assessment, including detailed imaging when indicated, may facilitate good outcomes. Two updated tables reflecting the summary of syndromic and non-syndromic systemic associations are provided to capture the details at a glance.

CONCLUSION

It is not very uncommon to find CLDA in syndromic or non-syndromic systemic disorders. Diagnosis of a craniofacial syndrome should prompt the physician to look out for CLDA. Similarly, a diagnosis of multiple CLDA should alert the examiner for the possible presence of associated systemic anomalies.

Preliminary report on screening IGSF3 gene mutation in families with congenital absence of lacrimal puncta and canaliculi

AIM

To investigate the variation of IGSF3 gene in three families with congenital absence of lacrimal puncta and canaliculi, and to lay a foundation for further research on the pathogenic gene of congenital lacrimal duct agenesis.

METHODS

The members of the three families were recruited. The ophthalmologic examinations in details, including slit-lamp biomicroscope, intraocular pressure and fundus examination, etc. were carried out. All patients were checked with paracentesis of puncta membrane and lacrimal duct probing, as well as the computed tomography-dacryocystography (CT-DCG). Peripheral blood of 14 participants (3 normal) from three families were collected, 4 mL each, for genomic DNA extraction, and 11 exon fragments of IGSF3 gene were amplified and sequenced by polymerase chain reaction (PCR) to determine whether there were IGSF3 genetic variation.

RESULTS

A total of 14 members from three families were screened for 4 synonymous variants: c.930C>T (p.Pro366=), c.1359T>C (p.Ser709=), c.1797G>A (p.Ser855=), c.1539G>A (p.Ser769=), and 6 missense variants: c.1507G>A (p.Gly759Ser), c.1783T>C (p.Trp851Arg), c.1952G>T (p.Ser 907Ile), c.3120C>G (p.Asp1040Glu), c.3123C>G (p.Asp1041Glu), c.3139_3140insGAC (p.Asp1046_Pro1047insAsp), and the latter three were only found in two patients with absence of lacrimal puncta and canaliculi combined with congenital osseous nasolacrimal canal obstruction from the first family.

CONCLUSION

The same IGSF3 gene mutation c.3139_3140insGAC is found in the patients with congenital absence of lacrimal puncta and canaliculi combine with osseous nasolacrimal canal obstruction.