A child with Kabuki syndrome and primary sclerosing cholangitis successfully treated with ursodiol and cholestryamine

What's new in pediatric genetic cholestatic liver disease: advances in etiology, diagnostics and therapeutic approaches

PURPOSE OF REVIEW

To highlight recent advances in pediatric cholestatic liver disease, including promising novel prognostic markers and new therapies.

FINDINGS

Identification of additional genetic variants associated with progressive familial intrahepatic cholestasis (PFIC) phenotype and new genetic cholangiopathies, with an emerging role of ciliopathy genes. Genotype severity predicts outcomes in bile salt export pump (BSEP) deficiency, and post-biliary diversion serum bile acid levels significantly affect native liver survival in BSEP and progressive familial intrahepatic cholestasis type 1 (FIC1 deficiency) patients. Heterozygous variants in the MDR3 gene have been associated with various cholestatic liver disease phenotypes in adults. Ileal bile acid transporter (IBAT) inhibitors, approved for pruritus in PFIC and Alagille Syndrome (ALGS), have been associated with improved long-term quality of life and event-free survival.

SUMMARY

Next-generation sequencing (NGS) technologies have revolutionized diagnostic approaches, while discovery of new intracellular signaling pathways show promise in identifying therapeutic targets and personalized strategies. Bile acids may play a significant role in hepatic damage progression, suggesting their monitoring could guide cholestatic liver disease management. IBAT inhibitors should be incorporated early into routine management algorithms for pruritus. Data are emerging as to whether IBAT inhibitors are impacting disease biology and modifying the natural history of the cholestasis.

Primary immunodeficiency in a patient with Kabuki syndrome

Kabuki syndrome is a well-known disease characterized by postnatal growth failure, dysmorphic facial features, skeletal abnormalities, and mental retardation associated with one of the pathogenic mutations in the KMT2D or KDM6A genes. At least 50% of individuals with Kabuki syndrome tend to develop recurrent infections and immune abnormalities, primarily hypogammaglobulinemia. The article describes the clinical course of resistant infectious syndrome in an 18-month-old child without typical dysmorphic and dermatoglyphic manifestations characteristic of Kabuki syndrome. A long history of resistant bacterial infection, enterocolitis, microcephaly, autistic-like behavior, hyperkinetic disorder, CT scan patterns of granulomatous lymphocytic interstitial lung disease (GLILD), suggested the immunodeficiency as part of a hereditary genetically determined syndrome. At the same time, the patient did not experience hypogammaglobulinemia characteristic of Kabuki syndrome. The upper normal response to previously received vaccination and a polyclonal repertoire of B-lymphocytes indicated the absence of disturbances in the humoral immunity. Immunophenotyping revealed the absence of T-regulatory cells (CD4+CD25++CD127–) as well as effector NK cells (CD16+CD56+CD3–) in the peripheral blood. The significant reduction of CD4+CD3+ T-lymphocytes and CD4+/CD8+ index was observed. In addition, no expression of integrin-beta (CD18) on neutrophils revealed.Conclusion. In children under the age of 2, Kabuki syndrome may present difficulties for clinical diagnosis due to the absence of distinctive phenotypic signs. Patients with mental disorders, congenital malformations, recurrent infections suspected of immunodeficiency should be carried out using molecular genetic exploration, including testing for mutations in the KMT2D and KDM6A.

Vitiligo in a Patient With Kabuki Syndrome: Case Study and Review of the Literature

Kabuki Syndrome (KS) is a rare genetic disorder characterized by dysmorphic facial features, skeletal anomalies, dermatoglyphic abnormalities, intellectual disability, and short stature. Autoimmune disease can be seen more frequently in this patient population. Vitiligo is an autoimmune disease that is uncommonly reported in patients with KS. This report describes a case of vitiligo manifesting in a patient with KS and discusses the use of Janus kinase inhibitors as treatment.

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.