Phenotypic variation in LADD syndrome

Lacrimo-auriculo-dento-digital syndrome: A case report and literature review

We report a healthy 18-year-old male Saudi with bilateral agenesis of the lacrimal puncta and canaliculi associated with large dacryocystocele on the right side without tearing or inflammation, detected in conjunction with other characteristic features of lacrimo-auriculo-dento-digital dysplasia syndrome. Computed tomography scan indicated that dacryocystoceles were bilateral and asymmetrical, with large dimensions at the right side and associated to a right side maxillary sinus mucocele. The right dacryocystocele was surgically removed, and the histology indicated characteristics of the lacrimal sac. The liquid content of the dacryocystocele was negative for microbes. The atypical mucocele in the maxillary sinus disappeared after dacryocystocele removal probably, due to recovery of sinus drainage.

An Essential Requirement for Fgf10 in Pinna Extension Sheds Light on Auricle Defects in LADD Syndrome

The pinna (or auricle) is part of the external ear, acting to capture and funnel sound toward the middle ear. The pinna is defective in a number of craniofacial syndromes, including Lacrimo-auriculo-dento-digital (LADD) syndrome, which is caused by mutations in FGF10 or its receptor FGFR2b. Here we study pinna defects in the Fgf10 knockout mouse. We show that Fgf10 is expressed in both the muscles and forming cartilage of the developing external ear, with loss of signaling leading to a failure in the normal extension of the pinna over the ear canal. Conditional knockout of Fgf10 in the neural crest fails to recapitulate this phenotype, suggesting that the defect is due to loss of Fgf10 from the muscles, or that this source of Fgf10 can compensate for loss in the forming cartilage. The defect in the Fgf10 null mouse is driven by a reduction in proliferation, rather than an increase in cell death, which can be partially phenocopied by inhibiting cell proliferation in explant culture. Overall, we highlight the mechanisms that could lead to the phenotype observed in LADD syndrome patients and potentially explain the formation of similar low-set and cup shaped ears observed in other syndromes.

Lacrimo-auriculo-dento-digital syndrome: A novel mutation in a Korean family and review of literature

Background

Lacrimo‐auriculo‐dento‐digital (LADD) syndrome is a rare autosomal dominant disorder caused by mutations in one of the three genes: fibroblast growth factor receptor 2 (FGFR2), FGFR3, or FGF10. Affected patients have hypoplasia/aplasia of lacrimal ducts/glands, hypoplasia/aplasia of salivary glands, dental anomalies, ear anomalies, hearing loss, and digital anomalies.

Case Presentation

Proband was an 11‐year‐old male with xerostomia, xerophthalmia, and a referring diagnosis of Sjogren syndrome. He presented with microdontia, hypodontia, low‐set/cupped ear auricles, and hearing loss in the left ear.

Methods

Whole exome sequencing (WES) was performed on proband. Variations and segregation within the family were verified using Sanger sequencing.

Results

Molecular studies revealed a novel heterozygous missense mutation in exon 11 of FGFR2: c.1547C>T (p.Ala516Val), compatible with LADD syndrome.

Conclusion

To the best of our knowledge, this is the first report of a family with LADD syndrome in Korea. The combination of xerostomia and xerophthalmia, seen in patients with LADD syndrome, may be misdiagnosed as Sjogren syndrome. WES may be a useful clinical tool in ascertaining the affected gene in patients with suspected genetic disorders. Here, a literature review and summary of 23 case reports/series of LADD syndrome are presented, which may help to identify patients with this condition.

Nuclear FGFR2 regulates musculoskeletal integration within the developing limb

BACKGROUND

Bent bone dysplasia syndrome (BBDS), a congenital skeletal disorder caused by dominant mutations in fibroblast growth factor receptor 2 (FGFR2), is characterized by bowed long bones within the limbs. We previously showed that the FGFR2 mutations in BBDS enhance nuclear and nucleolar localization of the receptor; however, exactly how shifts in subcellular distribution of FGFR2 affect limb development remained unknown.

RESULTS

Targeted expression of the BBDS mutations in the lateral plate mesoderm of the developing chick induced angulated hindlimbs, a hallmark feature of the disease. Whole-mount analysis of the underlying skeleton revealed bent long bones with shortened bone collars and, in severe cases, dysmorphic epiphyses. Epiphyseal changes were also correlated with joint dislocations and contractures. Histological analysis revealed that bent long bones and joint defects were closely associated with irregularities in skeletal muscle patterning and tendon-to-bone attachment. The spectrum of limb phenotypes induced by the BBDS mutations were recapitulated by targeted expression of wild-type FGFR2 appended with nuclear and nucleolar localization signals.

CONCLUSIONS

Our results indicate that the bent long bones in BBDS arise from disruptions in musculoskeletal integration and that increased nuclear and nucleolar localization of FGFR2 plays a mechanistic role in the disease phenotype. 248:233-246, 2019. © 2018 Wiley Periodicals, Inc.

A requirement for Fgfr2 in middle ear development

The skeletal structure of the mammalian middle ear, which is composed of three endochondral ossicles suspended within a membranous air-filled capsule, plays a critical role in conducting sound. Gene mutations that alter skeletal development in the middle ear result in auditory impairment. Mutations in fibroblast growth factor receptor 2 (FGFR2), an important regulator of endochondral and intramembranous bone formation, cause a spectrum of congenital skeletal disorders featuring conductive hearing loss. Although the middle ear malformations in multiple FGFR2 gain-of-function disorders are clinically characterized, those in the FGFR2 loss-of-function disorder lacrimo-auriculo-dento-digital (LADD) syndrome are relatively undescribed. To better understand conductive hearing loss in LADD, we examined the middle ear skeleton of mice with conditional loss of Fgfr2. We find that decreased auditory function in Fgfr2 mutant mice correlates with hypoplasia of the auditory bulla and ectopic bone growth at sites of tendon/ligament attachment. We show that ectopic bone associated with the intra-articular ligaments of the incudomalleal joint is derived from Scx-expressing cells and preceded by decreased expression of the joint progenitor marker Gdf5. Together, these results identify a role for Fgfr2 in development of the middle ear skeletal tissues and suggest potential causes for conductive hearing loss in LADD syndrome.

Dental issues in lacrimo-auriculo-dento-digital syndrome: An autosomal dominant condition with clinical and genetic variability

BACKGROUND AND OVERVIEW

Lacrimo-auriculo-dento-digital (LADD) syndrome is an autosomal dominant disorder with variable lacrimal and salivary gland hypoplasia and aplasia, auricular anomalies and hearing loss, dental defects and caries, and digital anomalies.

CASE DESCRIPTION

The authors present the cases of 2 unrelated children with enamel defects and history of dry mouth leading to recurrent dental caries. The referring diagnoses were Sjögren disease and hypohidrotic ectodermal dysplasia, respectively. The geneticist suspected LADD syndrome, which was confirmed by means of molecular studies showing mutations of 2 genes: fibroblast growth factor receptor 2 and fibroblast growth factor 10, respectively. Similarly affected relatives indicated an autosomal dominant inheritance. These relatives needed multiple dental rehabilitations during childhood and dentures in adulthood.

CONCLUSIONS AND PRACTICAL IMPLICATIONS

Dry mouth, multiple caries, enamel defects, and abnormal tooth morphology were the reasons for seeking care from dentists. However, clinical evaluation and diagnostic imaging studies helped identify anomalies of the lacrimal and salivary glands, ears, and digits, indicating involvement of different areas of the body, compatible with LADD syndrome. Accordingly, dentists should consider genetic disorders in patients with multiple anomalies. For instance, oculodentodigital syndrome, oral-facial-digital syndrome, and LADD syndrome (among others) may have dental issues as the major clinical manifestation. Accurate identification of a particular syndrome is now commonplace with the use of genetic testing. When a patient has multiple anomalies suggestive of a syndromic condition, appropriate genetic testing can help verify the clinical diagnosis. Keeping genetics in mind helps earlier identification of other affected family members with diagnostic genetic testing and appropriate treatment; the economic advantage is to shorten the diagnostic odyssey and possibly preserve dentition.

A Case of Lacrimo-Auriculo-Dento-Digital Syndrome with Multiple Congenitally Missing Teeth

Lacrimo-auriculo-dento-digital (LADD) syndrome is an extremely rare disorder which may occur sporadically or inheritably as an autosomal dominant condition. It is characterized by defects in the lacrimal apparatus, ear problems, and dental and digital abnormalities. However, specific symptoms vary greatly among the cases with a high degree of overlap with other similar genetic disorders. Here, we describe a 7-year-old boy with LADD syndrome, clinical and radiological findings, dental treatment undertaken, and its differential diagnosis.

Salivary Gland Dysplasia in Fgf10 Heterozygous Mice: A New Mouse Model of Xerostomia

Xerostomia, or chronic dry mouth, is a common syndrome caused by a lack of saliva that can lead to severe eating difficulties, dental caries and oral candida infections. The prevalence of xerostomia increases with age and affects approximately 30% of people aged 65 or older. Given the large numbers of sufferers, and the potential increase in incidence given our aging population, it is important to understand the complex mechanisms that drive hyposalivation and the consequences for the dentition and oral mucosa. From this study we propose the Fgf10 +/- mouse as a model to investigate xerostomia. By following embryonic salivary gland development, in vivo and in vitro, we show that a reduction in Fgf10 causes a delay in branching of salivary glands. This leads to hypoplasia of the glands, a phenotype that is not rescued postnatally or by adulthood in both male and female Fgf10 +/- mice. Histological analysis of the glands showed no obvious defect in cellular differentiation or acini/ductal arrangements, however there was a significant reduction in their size and weight. Analysis of saliva secretion showed that hypoplasia of the glands led to a significant reduction in saliva production in Fgf10 +/- adults, giving rise to a reduced saliva pellicle in the oral cavity of these mice. Mature mice were shown to drink more and in many cases had severe tooth wear. The Fgf10 +/- mouse is therefore a useful model to explore the causes and effects of xerostomia.

Congenital keratoconjunctivitis sicca and ichthyosiform dermatosis in 25 Cavalier King Charles spaniel dogs. Part I: clinical signs, histopathology, and inheritance

The clinical presentation and progression (over 9 months to 13 years) of congenital keratoconjunctivitis sicca and ichthyosiform dermatosis (CKCSID) in the Cavalier King Charles spaniel dog are described for six new cases and six previously described cases. Cases presented with a congenitally abnormal (rough/curly) coat and signs of KCS from eyelid opening. Persistent scale along the dorsal spine and flanks with a harsh frizzy and alopecic coat was evident in the first few months of life. Ventral abdominal skin was hyperpigmented and hyperkeratinized in adulthood. Footpads were hyperkeratinized from young adulthood with nail growth abnormalities and intermittent sloughing. Long-term follow-up of cases (13/25) is described. Immunomodulatory/lacrimostimulant treatment had no statistically significant effect on Schirmer tear test results, although subjectively, this treatment reduced progression of the keratitis. Histopathological analysis of samples (skin/footpads/lacrimal glands/salivary glands) for three new cases was consistent with an ichthyosiform dermatosis, with no pathology of the salivary or lacrimal glands identified histologically. Pedigree analysis suggests the syndrome is inherited by an autosomal recessive mode.

Case report: Presentation of lacrimo-auriculodento- digital (LADD) syndrome in a young female patient

BACKGROUND

Lacrimo-auriculo-dento-digital (LADD) syndrome (OMIM #149730) is an autosomal-dominant congenital disorder that can be caused by heterozygous mutations in the tyrosine kinase domains of the genes encoding fibroblast growth factor receptors 2 (FGFR2) and 3 (FGFR3), and has been found in association with a mutation in the FGF10 gene, which encodes an Fgfr ligand. Clinical signs vary, but the condition is characterised by involvement of the lacrimal and salivary systems, cup-shaped ears, hearing loss and dental abnormalities. Additional features may include involvement of the hands and feet with other body systems particularly the kidneys.

CASE REPORT

Previous literature on the subject has been reviewed and this case is the first presentation of LADD syndrome in the Republic of Ireland, as a sporadic case in a 12-year-old girl who exhibited a range of dental and digital anomalies.

TREATMENT

Her general medical practitioner managed her medical care whilst her oral care necessitated a multidisciplinary approach involving restorative and orthodontic elements.

FOLLOW-UP

The initial restorative phase of treatment has successfully improved the appearance of the patient's anterior teeth using direct resin composite build-ups.

Orodental findings of a family with lacrimo-auriculo-dento digital (LADD) syndrome

Lacrimo-auriculo-dento-digital (LADD) syndrome is an autosomal dominantly inherited disorder characterized mainly by hypoplasia/aplasia of lacrimal and salivary tracts, small cup-shaped and/or malformed ears, sensorineuronal or conductive hearing loss, abnormalities of the teeth, and variable anomalies of the hands and feet. In this case report, general and dentofacial features of 2 siblings and their father are described. Both siblings presented hypoplastic lacrimal puncta, cup-shaped/low-set ears with bilateral sensorineuronal hearing loss, broad first toes, and bilateral clinodactyly of the fifth toes. The 17-year-old female revealed mainly peg-shaped incisors, long thin-rooted teeth, malformed molars, microdontia, and enamel hypoplasia; and the 10-year-old male showed a short lingual frenulum, peg-shaped incisors, shallow cusps, agenesis of mandibular second premolars, and taurodontism. Father exhibited hypoplastic puncta, hypolacrimia, mild bilateral sensorineural hearing loss, taurodontism, and absence of some teeth. In conclusion, this case report of a family has demonstrated the various general and orofacial features encountered in LADD syndrome.

Characteristics of lacrimo-auriculo-dento-digital (LADD) syndrome: case report of a family and literature review

We describe a family with lacrimo-auriculo-dento-digital syndrome (LADD). A 13-year-old boy had cup-shaped ears, deafness, unilateral choanal atresia, bilateral nasolacrimal duct obstruction, xerostomia, alacrima due to congenital absence of lacrimal glands, agenesis of salivary glands, chronic dacryocystitis, keratoconjunctivitis sicca, ptosis, nail dysplasia of the thumb, shortness of fifth toe, temporal bone abnormality and epilepsy. His younger sister had shortened middle phalanx of fifth digits. His middle sister had hypodontia, shortened distal phalanx of fifth digit, agenesis of salivary glands, mild hearing loss and exotropia. His older sister had left nasolacrimal duct obstruction and aplasia of both parotid glands. The oldest sister had hypodontia and divergent excess exotropia. His mother had hypodontia. These findings are consistent with LADD syndrome. An autosomal dominant pattern of inheritance with variable expressivity has been demonstrated. Renal and uro-genital anomalies have been noted variably.

LADD syndrome is caused by FGF10 mutations

Lacrimo-auriculo-dento-digital syndrome [LADD (MIM 149730)] is an autosomal-dominant multiple congenital anomaly disorder characterized by aplasia, atresia or hypoplasia of the lacrimal and salivary systems, cup-shaped ears, hearing loss, and dental and digital anomalies. Loss of function mutations in FGF10 were recently described in aplasia of the lacrimal and salivary glands [ALSG (MIM 180920; MIM 103420)] (Entesarian et al., Nat Genet 2005: 37: 125-127, Milunsky et al., American College of Medical Genetics Annual Meeting, Dallas, TX, 2005: A100). Due to the significant phenotypic overlap between LADD syndrome and ALSG and the variable expressivity of both the disorders, we hypothesized that FGF10 mutations could also result in LADD syndrome. A de novo missense mutation was found in exon 3 of FGF10 in a 3-year-old female (Family 1) with LADD syndrome. This missense mutation, resulting in a non-conservative amino acid change, was confirmed by restriction enzyme digestion and was not found in 500 control chromosomes. A nonsense mutation was also found in exon 2 of FGF10 (Family 2) in a 19-year-old mother with ALSG and her 2-year-old daughter with LADD syndrome. Previous studies of FGF10 mutant mice have demonstrated abnormalities consistent with ALSG and LADD syndrome. We conclude that ALSG and LADD syndrome may represent variable presentations of the same clinical spectrum caused by FGF10 mutations.

CT findings of head and neck anomalies in lacrimo-auriculo-dento-digital (LADD) syndrome

We present computed tomography (CT) findings of a boy with lacrimo-auriculo-dento-digital (LADD) syndrome. Bilateral lacrimal glands were not detected and CT imaging of this abnormality in LADD syndrome has not been reported before. Despite suggestions from previous reports of multiple temporal bone abnormalities resulting in hearing losses in these patients, only minor temporal bone abnormalities were seen in our deaf-mute patient. Dysplasia of salivary glands was noted. CT findings of head and neck abnormalities in LADD syndrome are discussed.

Lacrimoauriculodentodigital syndrome with cleft lip/palate and renal manifestations

OBJECTIVE

To describe the largest family reported with the lacrimoauriculodentodigital (LADD) syndrome.

DESIGN

A family study of eight individuals with LADD syndrome.

SETTING

Pediatric Clinical Research Center at Oakland Children's Hospital.

PATIENTS

Eight individuals in a four-generation family.

MAIN OUTCOME MEASURE

A diagnosis of LADD syndrome was determined by the presence of one or more of the characteristic lacrimal duct, auricular, dental, or digital malformations. Tear function and orofacial clefting were also considered in the final diagnosis of LADD syndrome.

RESULTS

Affected family members had the characteristic features of LADD syndrome, including cup-shaped ears; lacrimal duct obstruction; and dental, forearm, and digit malformations. In addition to the cardinal features of LADD syndrome, the proband was born with cleft lip and palate. The mother and sister of the proband have hydronephrosis, a rare feature of the disorder. Family members also have features not previously described in LADD syndrome, including vesicoureteral reflux, recurrent urinary tract infections, camptodactyly, distal thumb symphalangism, and a bicornuate uterus.

CONCLUSIONS

The findings suggest that the presence of vesicoureteral reflux and recurrent urinary tract infections should be evaluated in LADD syndrome patients and that the distinction of LADD syndrome from ectrodactyly-ectodermal dysplasia and clefting syndrome by the absence of clefting may need to be reconsidered.

The Lacrimo-Auriculo-Dento-Digital (LADD) syndrome: temporal bone CT findings

The temporal bone CT examination of a 16-year-old female patient with the LADD syndrome or Levy-Hollister syndrome showed multiple bilateral middle as well as inner ear malformations. Ossicular chain anomalies were seen, especially of the incus and stapes. The oval window was very narrow to absent. Both cochleas were hypoplastic and showed modiolar deficiency. A common cavity between the vestibule and lateral semicircular canal was bilaterally present.

Clinical and radiographic features of the lacrimo-auriculo-dento-digital syndrome

Lacrimo-auriculo-dento-digital syndrome is an autosomal dominant malformation complex that affects craniofacial structures including the teeth and salivary glands. There have been several cases of this syndrome reported to date. A family with three affected members is presented. In addition to several of the clinical manifestations of lacrimo-auriculo-dento-digital syndrome, these subjects also show previously unreported radiographic features of the syndrome as demonstrated by panoramic radiographic examination and corrected axis linear tomography of the temporomandibular joints.

Lacrimo-auricolo-dento-digital syndrome mimicking primary juvenile Sjögren's syndrome

We describe a 24 year old female patient affected with symptoms of severe xerostomia and keratoconjunctivitis sicca since her childhood. She also had several malformations involving face and digits as well as cup shaped ears, enamel dysplasia and absence of lacrimal puncta. Hence, the diagnosis of Lacrimo-Auricolo-Dento-Digital (LADD) syndrome was made. The main differences between this rare, inherited disease and primary juvenile Sjögren's syndrome are pointed out.

Split hand/split foot deformity and LADD syndrome in a family: overlap between the EEC and LADD syndromes

A mother and daughter are reported with apparently dissimilar syndromes. The mother has a split hand/split foot deformity and the daughter a condition consistent with a diagnosis of LADD syndrome. Absence of clefting and deficient formation of saliva and tears are the main signs that differentiate the LADD from the EEC syndrome. However, no distinct feature is constant between these two autosomal dominant disorders that show great phenotypic variability. This report emphasises the overlap between the LADD and the EEC syndromes.

Ocular manifestations of the lacrimo-auriculo-dento-digital syndrome

We studied a mother and daughter with an extremely rare constellation of signs and symptoms. One or both had absent lacrimal puncta, nasolacrimal duct obstruction, chronic dacryocystitis, dry eyes, and epiphora. Systemic findings included salivary gland hyposecretion, dental hypoplasia and dysplasia, cup-shaped ears with hearing loss, and digital anomalies. These findings are consistent with those of the lacrimo-auriculo-dento-digital syndrome, a genetic disorder. Our study supports the autosomal dominant inheritance of this syndrome, delineates the ophthalmic manifestations, and provides evidence that renal anomalies are part of the disorder.

Lacrimo-auriculo-dento-digital syndrome: evidence for lower limb involvement and severe congenital renal anomalies

We describe a 3-generation family with lacrimo-auriculo-dento-digital syndrome (LADD). In addition to the well described abnormalities of ears, teeth, lacrimal apparatus and digits, the patients exhibit several previously undescribed anomalies, including minor facial anomalies (broad forehead, telecanthus, bulbous nasal tip, full jaw, ptosis and flared nostrils), involvement of the first and second toes, and congenital renal disease causing death in the neonatal period in 2 cases.

Heredity and dysmorphic syndromes in congenital limb deficiencies

Isolated limb deficiencies are usually sporadic occurrences. However, if they are associated with other abnormalities or a family history, the risk to future pregnancies may be as high as 50%. A thorough history, examination and investigation of the baby as well as the parents is essential before assessing this recurrence risk. The syndromes associated with limb deficiencies are presented.

EEC syndrome: report on 20 new patients, clinical and genetic considerations

We report on 20 Brazilian patients (11 sporadic and 9 familial cases) with the ectrodactyly, ectodermal dysplasia, clefting syndrome (EEC syndrome). Genetic aspects, clinical manifestations, and differential diagnosis of the syndromes involving ectodermal dysplasia/limb anomalies and cleft lip/palate are discussed.

Lacrimo-auriculo-dento-digital (LADD) syndrome with renal and foot anomalies

A patient who presented with most features of lacrimo-auriculo-dento-digital (LADD) syndrome, an autosomal dominant trait, is described. There was no deafness, and anomalies of the external ear and the upper limbs were discrete. Renal anomalies, consisting of progressive caliectasis with stone formation, were revealed by macroscopic hematuria. There were also skeletal anomalies of both feet, a feature not previously described. Renal and distal limb anomalies are probably features of LADD syndrome.

LADD syndrome: report of new cases and review of the clinical spectrum

The lacrimo-auriculo-dento-digital or LADD syndrome is a true multiple congenital anomalies (MCA) syndrome characterized by hypoplasias, aplasias or atresias in the lacrimal system; anomalies of the ears and hearing loss; hypoplasias, aplasias or atresias in the region of the salivary system; dental anomalies; and digital malformations. The syndrome is thought to be an autosomal dominant trait with variable expressivity. It seems to be rare. Two new cases are reported and the clinical spectrum of the syndrome is reviewed. The paediatrician who is responsible for the child as a whole individual should know the LADD syndrome. Its early recognition may be important.