Diagnosis implications of the whole genome sequencing in a large Lebanese family with hyaline fibromatosis syndrome

Hyaline Fibromatosis Syndrome: Early Outcomes Following Major Craniofacial Mass Excision

Hyaline fibromatosis syndrome (HFS) is a rare congenital disorder characterized by abnormal hyaline deposition within soft tissues. Hyaline fibromatosis syndrome manifests in 2 distinct forms: (1) infantile systemic hyalinosis and (2) juvenile hyaline fibromatosis. Infantile systemic hyalinosis, the more severe form, typically emerges in early childhood with extensive systemic involvement. In contrast, juvenile HFS is less severe, allowing patients to survive into adulthood. Common clinical manifestations include thickened skin, hyperpigmented patches, gingival hypertrophy, skin nodules, and progressive severe joint contractures, leading to significant morbidity and potential mortality. This case report describes a 7-year-old child who was diagnosed with HFS and presented with a very large, ulcerated, rapidly expanding craniofacial mass. The patient underwent successful treatment involving a multidisciplinary medical team and strategic surgical intervention, achieving favorable postoperative outcomes.

Juvenile Hyaline Fibromatosis: Report of a Case with a Novel ANTXR2 Gene Mutation

BACKGROUND Juvenile hyaline fibromatosis is a rare autosomal recessive disorder with unknown prevalence characterized by abnormal development of hyalinized fibrous tissue usually in the skin, mucosa, bone, and often the internal organs. Here, we report the case of a 7-year-old girl from a family with ANTXR2 mutation confirming JHF. CASE REPORT The girl presented with multiple painless soft-tissue swellings affecting the ears, forehead, and scalp. Excisional biopsies of the masses reported positive immunohistochemical staining for collagen type VI in the extracellular matrix area, which indicated collagen VI accumulation. Genetic analysis was performed using whole-exome sequencing. The variants were further validated using Sanger sequencing in trio-based approach. We identified a novel mutation, c.1273_1293delinsTCTTGTGGGTTTGGCT in exon 15 of ANTXR2 gene, leading to a frameshift of the amino acid from codon 425 to all the rest of the amino acid chain (p.Pro425Serfs). The change of an encoded protein interrupted lysosome-mediated degradation of collagen VI. This finding was compatible with her parents whose genetic tests were both positive for the same heterogenous deletion/insertion mutation. The patient was treated with surgical excision of the tumor masses, which had to be repeated several times due to recurrences. CONCLUSIONS This novel mutation in exon 15 of the ANTXR2 gene may help improve understanding of genotype-phenotype correlations for this syndrome and provide the basis for diagnostic testing. A multidisciplinary team approach including genetic molecular testing is required for an accurate diagnosis and management of JHF for conducting genetic counseling for affected families as a part of holistic management.

Hyaline fibromatosis syndrome: a case presenting with gingival enlargement as the only clinical manifestation and a report of two new mutations in the ANTXR2 gene

BACKGROUND

Hyaline fibromatosis syndrome (HFS) is a rare autosomal recessive disorder caused by mutations in the gene for anthrax toxin receptor-2 (ANTXR2). The clinical features of HFS include skin thickening with nodules, papules and plaques, gingival enlargement, joint stiffness and contractures, and systemic manifestations. Notably, in all patients with HFS reported in the literature, gingival enlargement has never occurred alone.

CASE PRESENTATION

A case of a child with gingival enlargement as the only clinical manifestation, who was later diagnosed with HFS, is described. In this case, the absence of skin and joint lesions and other characteristic clinical presentations gave rise to a diagnostic problem. This uncommon condition was clinically indistinguishable from other diseases or conditions that presented with diffuse gingival enlargement. A definitive diagnosis of HFS was reached through genetic analysis. Trio whole exome sequencing revealed compound heterozygous mutations of ANTXR2 in this patient and two new mutations were reported.

CONCLUSIONS

The findings of this case serve as an important reminder to clinicians. When dental practitioners encounter gingival manifestations of HFS without accompanied skin or joint involvement, there is a need to pay attention to the differential diagnosis and increase awareness of HFS.

The physical education and the Infantile Systemic Hyalinosis: A case report

The purpose of this case report is to present the case study of a child with Systemic Infantile Hyalinosis in the educational attendance specialized in Physical Education and Art (dance). The collection took place through the Teachers' Field Diary and the interview with the child's mother. The pedagogical intervention lasted 15 months and took place at the swimming and dance workshops at the Catholic University of Brasilia, with two weekly classes in each workshop lasting 30 min each. The intervention was based on Henri Wallon's theory of emotions and sought freedom of expression, body experience, and the discovery of a body marked by disease and, in many moments, disrespected in its possibilities. At the end of the intervention, mobility, and range of motion gains were observed in motor terms, which were compromised due to the instability caused by the progressive disease. However, there were significant gains regarding self-esteem, which were relevant and significantly contributed to a better quality of life of the child.

Hyaline fibromatosis syndrome: Clinical update and phenotype-genotype correlations

Hyaline fibromatosis syndrome (HFS) is the unifying term for infantile systemic hyalinosis and juvenile hyaline fibromatosis. HFS is a rare autosomal recessive disorder of the connective tissue caused by mutations in the gene for anthrax toxin receptor-2 (ANTXR2). It is characterized by abnormal growth of hyalinized fibrous tissue with cutaneous, mucosal, osteoarticular, and systemic involvement. We reviewed the 84 published cases and their molecular findings, aiming to gain insight into the clinical features, prognostic factors, and phenotype-genotype correlations. Extreme pain at minimal handling in a newborn is the presentation pattern most frequently seen in grade 4 patients (life-limiting disease). Gingival hypertrophy and subcutaneous nodules are some of the disease hallmarks. Though painful joint stiffness and contractures are almost universal, weakness and hypotonia may also be present. Causes of death are intractable diarrhea, recurrent infections, and organ failure. Median age of death of grade 4 cases is 15.0 months (p25-p75: 9.5-24.0). This review provides evidence to reinforce the previous hypothesis that missense mutations in exons 1-12 and mutations leading to a premature stop codon lead to the severe form of the disease, while missense pathogenic variants in exons 13-17 lead to the mild form of the disease. Multidisciplinary team approach is recommended.