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Li JYM, Ho FTW, Lee M, Chan J, Chung BHY, Tung JYL, Ma ALT. A case report of multicentric carpotarsal osteolysis syndrome: Depiction of a debilitating disease course. Am J Med Genet A 2024; 194:e63616. [PMID: 38551204 DOI: 10.1002/ajmg.a.63616] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2024] [Revised: 03/06/2024] [Accepted: 03/21/2024] [Indexed: 07/05/2024]
Abstract
Multicentric carpotarsal osteolysis syndrome (MCTO) is a rare skeletal disorder characterized by progressive osteolysis involving the carpal and tarsal bones, and often associated with nephropathy. It is caused by heterozygous mutation in the MAF bZIP transcription factor B (MAFB) gene. Heterogeneous clinical manifestation and wide spectrum of disease severity have been observed in patients with MCTO. Here, we report a case of a male patient who presented with kidney failure in childhood with progressive disabling skeletal deformity. He was diagnosed with MCTO at 31-years-old, where a de novo pathogenic heterozygous variant in NM_005461.5:c.212C>A: p.(Pro71His) of the MAFB gene was identified. While there has been little data on the long-term prognosis and life expectancy of this disease, this case report sheds light on the debilitating disease course with multiple significant morbidities of a patient with MCTO throughout his lifetime of 33 years.
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Affiliation(s)
| | - Fanny Tsz-Wai Ho
- Paediatric Nephrology, Hong Kong Children's Hospital, Hong Kong, China
| | - Mianne Lee
- Department of Paediatrics and Adolescent Medicine, School of Clinical Medicine, Li Ka Shing Faculty of Medicine, The University of Hong Kong, Hong Kong, China
| | - Joyce Chan
- Paediatric Radiology, Hong Kong Children's Hospital, Hong Kong, China
| | - Brian Hon-Yin Chung
- Department of Paediatrics and Adolescent Medicine, School of Clinical Medicine, Li Ka Shing Faculty of Medicine, The University of Hong Kong, Hong Kong, China
| | | | - Alison Lap-Tak Ma
- Paediatric Nephrology, Hong Kong Children's Hospital, Hong Kong, China
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2
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Kisla Ekinci RM, Ozalp O, Anlas O, Atmis B, Ata A, Balci S. An unusual manifestation in a pediatric patient with MAFB mutation: Sacroiliitis in multicentric carpotarsal osteolysis syndrome. Int J Rheum Dis 2023; 26:2064-2068. [PMID: 37088798 DOI: 10.1111/1756-185x.14700] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2023] [Revised: 03/25/2023] [Accepted: 04/08/2023] [Indexed: 04/25/2023]
Abstract
Multicentric carpotarsal osteolysis (MCTO) syndrome, is typically characterized by progressive bone resorption in especially carpal and tarsal bones, in addition to abnormal facial appearance and proteinuria. This disorder is caused by monoallelic pathogenic MAFB mutations, which result in excessive osteoclastogenesis via aberrant receptor activator of nuclear factor kappa-B ligand activation. Most cases are sporadic with de-novo mutations, and it is still unclear why carpal and tarsal bones are predominantly affected. The early phases of MCTO resemble juvenile idiopathic arthritis (JIA) with ankle and wrist swelling and pain, even with inflammatory changes in magnetic resonance imaging. Herein we report a pediatric patient, previously treated with antirheumatic drugs, and eventually diagnosed with MCTO. This case was a descriptive case with exophthalmos, significant proteinuria, and total loss of carpal and tarsal bones at the time of genetic diagnosis. Similar to the literature, our case had typical radiological findings despite methotrexate and anti-tumor necrosis factor-alpha treatment. However, while arthritis affecting joints other than wrists and ankles has not been reported so far in the literature, our case had bilateral sacroiliitis which completely resolved after adalimumab treatment. We cannot be sure if sacroiliitis was incidental or occurred as a component of the disease, nonetheless, we think that sharing our experience may lead to easy and early recognition of MCTO, with more knowledge on rare manifestations of MCTO, and thus we may be able to clarify the benefits of denosumab, which is the most promising agent in early phases of the disease.
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Affiliation(s)
| | - Ozge Ozalp
- Department of Medical Genetics, Adana City Training and Research Hospital, Adana, Turkey
| | - Ozlem Anlas
- Department of Medical Genetics, Adana City Training and Research Hospital, Adana, Turkey
| | - Bahriye Atmis
- Department of Pediatric Nephrology, Cukurova University Faculty of Medicine, Adana, Turkey
| | - Aysun Ata
- Department of Pediatric Endocrinology, Adana City Training and Research Hospital, Adana, Turkey
| | - Sibel Balci
- Department of Pediatric Rheumatology, Kayseri City Training and Research Hospital, Kayseri, Turkey
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3
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Lerman MA, Francavilla M, Waqar‐Cowles L, Levine MA. Denosumab Treatment Does Not Halt Progression of Bone Lesions in Multicentric Carpotarsal Osteolysis Syndrome. JBMR Plus 2023; 7:e10729. [PMID: 37197321 PMCID: PMC10184019 DOI: 10.1002/jbm4.10729] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/31/2022] [Revised: 01/11/2023] [Accepted: 02/01/2023] [Indexed: 02/10/2023] Open
Abstract
Here we report the use of denosumab, a monoclonal antibody against receptor activator of nuclear factor κB ligand (RANKL), as monotherapy for multicentric carpotarsal osteolysis syndrome (MCTO) in an 11.5-year-old male with a heterozygous missense mutation in MAFB (c.206C>T; p.Ser69Leu). We treated the subject with 0.5 mg/kg denosumab every 60-90 days for 47 months and monitored bone and mineral metabolism, kidney function, joint range of motion (ROM), and bone and joint morphology. Serum markers of bone turnover reduced rapidly, bone density increased, and renal function remained normal. Nevertheless, MCTO-related osteolysis and joint immobility progressed during denosumab treatment. Symptomatic hypercalcemia and protracted hypercalciuria occurred during weaning and after discontinuation of denosumab and required treatment with zoledronate. When expressed in vitro, the c.206C>T; p.Ser69Leu variant had increased protein stability and produced greater transactivation of a luciferase reporter under the control of the PTH gene promoter than did wild-type MafB. Based on our experience and that of others, denosumab does not appear to be efficacious for MCTO and carries a high risk of rebound hypercalcemia and/or hypercalciuria after drug discontinuation. © 2023 The Authors. JBMR Plus published by Wiley Periodicals LLC on behalf of American Society for Bone and Mineral Research.
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Affiliation(s)
- Melissa A. Lerman
- Division of RheumatologyThe Children's Hospital of Philadelphia and Department of Pediatrics, University of Pennsylvania Perelman School of MedicinePhiladelphiaPAUSA
| | - Michael Francavilla
- Department of RadiologyWhiddon College of Medicine, University of South AlabamaMobileALUSA
| | - Lindsay Waqar‐Cowles
- Division of RheumatologyThe Children's Hospital of Philadelphia and Department of Pediatrics, University of Pennsylvania Perelman School of MedicinePhiladelphiaPAUSA
| | - Michael A. Levine
- Division of Endocrinology and Diabetes and Center for Bone HealthThe Children's Hospital of Philadelphia and Department of Pediatrics, University of Pennsylvania Perelman School of MedicinePhiladelphiaPAUSA
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4
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Shakiba M, Alaei F. A novel gene mutation for multicentric osteolysis nodulosis and arthropathy: Case report and review of literature. Heliyon 2023; 9:e14865. [PMID: 37025869 PMCID: PMC10070892 DOI: 10.1016/j.heliyon.2023.e14865] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2022] [Revised: 03/18/2023] [Accepted: 03/20/2023] [Indexed: 03/29/2023] Open
Abstract
Frank-Ter Haar syndrome (FTHS), Winchester syndrome (WS), Torg syndrome (TS) and Multicentric Osteolysis Nodulosis and Arthropathy (MONA) are progressive skeletal dysplasia consisting of acro-osteolysis. Mutation in Matrix Metalloproteinase 2 (MMP2), Matrix Metalloproteinase 14 (MMP14) and SH3PXD2B are known genetic defects in these disorders. We hereby report a 5 years and 9 months old girl suffering from progressive limb deformity. She is the first child of a relative couple, who was referred to metabolic disorders' clinic due to poor growth and bone pain. On physical examination, minor facial dysmorphism, hypertrichosis, severe hand deformity with limitation in range of motion in carpal, metacarpal and phalangeal joints, hallux valgus deformity of feet, soft tissue hypertrophy and nodule formation in palmoplantar areas were detected. Her past history indicated a cardiac defect resulting in open heart surgery at 8 months of age. Genetic study revealed a new homozygote nonsense mutation in MMP2 gene explaining her clinical manifestations. We recommend careful evaluation and follow-up of patients with congenital heart disease, as it may be the first presentation of a genetic multisystem disorder. Early differentiation of the disease from other skeletal dysplasia and rheumatologic disorders could prevent unnecessary management.
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Ma NS, Mumm S, Takahashi S, Levine MA. Multicentric Carpotarsal Osteolysis: a Contemporary Perspective on the Unique Skeletal Phenotype. Curr Osteoporos Rep 2023; 21:85-94. [PMID: 36477366 PMCID: PMC10393442 DOI: 10.1007/s11914-022-00762-7] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 10/18/2022] [Indexed: 12/12/2022]
Abstract
PURPOSE OF REVIEW Multicentric carpotarsal osteolysis (MCTO) is an ultra-rare disorder characterized by osteolysis of the carpal and tarsal bones, subtle craniofacial deformities, and nephropathy. The molecular pathways underlying the pathophysiology are not well understood. RECENT FINDINGS MCTO is caused by heterozygous mutations in MAFB, which encodes the widely expressed transcription factor MafB. All MAFB mutations in patients with MCTO result in replacement of amino acids that cluster in a phosphorylation region of the MafB transactivation domain and account for a presumed gain-of-function for the variant protein. Since 2012, fewer than 60 patients with MCTO have been described with 20 missense mutations in MAFB. The clinical presentations are variable, and a genotype-phenotype correlation is lacking. Osteolysis, via excessive osteoclast activity, has been regarded as the primary mechanism, although anti-resorptive agents demonstrate little therapeutic benefit. This paper appraises current perspectives of MafB protein action, inflammation, and dysfunctional bone formation on the pathogenesis of the skeletal phenotype in MCTO. More research is needed to understand the pathogenesis of MCTO to develop rational therapies.
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Affiliation(s)
- Nina S Ma
- Section of Pediatric Endocrinology, Children's Hospital Colorado and Department of Pediatrics, University of Colorado School of Medicine, 13123 E. 16th Ave, B265, Aurora, CO, 80045, USA.
| | - S Mumm
- Division of Bone and Mineral Diseases, Washington University School of Medicine and Center for Metabolic Bone Disease and Molecular Research, Shriners Children's, St. Louis, MO, USA
| | - S Takahashi
- Laboratory Animal Resource Center in Transborder Medical Research Center, Faculty of Medicine, University of Tsukuba, Ibaraki, Japan
| | - M A Levine
- Center for Bone Health and Division of Endocrinology and Diabetes, The Children's Hospital of Philadelphia and the Department of Pediatrics, University of Pennsylvania Perelman School of Medicine, Philadelphia, PA, USA
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Morito N, Usui T, Ishibashi S, Yamagata K. Podocyte-specific Transcription Factors: Could MafB Become a Therapeutic Target for Kidney Disease? Intern Med 2023; 62:11-19. [PMID: 35249929 PMCID: PMC9876710 DOI: 10.2169/internalmedicine.9336-22] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/04/2023] Open
Abstract
The increasing number of patients with chronic kidney disease (CKD) is being recognized as an emerging global health problem. Recently, it has become clear that injury and loss of glomerular visceral epithelial cells, known as podocytes, is a common early event in many forms of CKD. Podocytes are highly specialized epithelial cells that cover the outer layer of the glomerular basement membrane. They serve as the final barrier to urinary protein loss through the formation and maintenance of specialized foot-processes and an interposed slit-diaphragm. We previously reported that the transcription factor MafB regulates the podocyte slit diaphragm protein production and transcription factor Tcf21. We showed that the forced expression of MafB was able to prevent CKD. In this review, we discuss recent advances and offer an updated overview of the functions of podocyte-specific transcription factors in kidney biology, aiming to present new perspectives on the progression of CKD and respective therapeutic strategies.
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Affiliation(s)
- Naoki Morito
- Department of Nephrology, Faculty of Medicine, University of Tsukuba, Japan
| | - Toshiaki Usui
- Department of Nephrology, Faculty of Medicine, University of Tsukuba, Japan
| | - Shun Ishibashi
- Department of Nephrology, Faculty of Medicine, University of Tsukuba, Japan
| | - Kunihiro Yamagata
- Department of Nephrology, Faculty of Medicine, University of Tsukuba, Japan
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Drovandi S, Lugani F, Boyer O, La Porta E, Giordano P, Hummel A, Knebelmann B, Cornet J, Baujat G, Lipska-Ziętkiewicz BS, Ghiggeri GM, Caridi G, Angeletti A. Multicentric Carpotarsal Osteolysis Syndrome Associated Nephropathy: Novel Variants of MAFB Gene and Literature Review. J Clin Med 2022; 11:4423. [PMID: 35956038 PMCID: PMC9369440 DOI: 10.3390/jcm11154423] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2022] [Revised: 07/25/2022] [Accepted: 07/26/2022] [Indexed: 02/05/2023] Open
Abstract
Multicentric carpo-tarsal osteolysis (MCTO) is a rare osteolysis syndrome mainly involving carpal and tarsal bones usually presenting in early childhood. MCTO has autosomal dominant inheritance with heterozygous mutation in the MAFB gene. The skeletal disorder is often associated with chronic kidney disease. Data on clinical characterization and best treatment option of MCTO-associated nephropathy are scarce and mostly limited to case reports. With the aim to better define the phenotype and long-term outcomes of MCTO-associated nephropathy, we launched an online survey through the Workgroup for hereditary glomerulopathies of the European Rare Kidney Disease Network (ERKNet). Overall, we collected clinical and genetic data of 54 MCTO patients, of which 42 previously described and 12 new patients. We observed a high rate of kidney involvement (70%), early age of kidney disease onset, nephrotic-range proteinuria, and a kidney survival around of 40% at long-term follow-up. Our finding confirmed the heterogeneity of clinical manifestations and widen the spectrum of phenotypes resulting from MCTO-associated nephropathy. Furthermore, we report the first case of complete remission after treatment with cyclosporine A. We demonstrated that multidisciplinary care is essential for MCTO patients and early referral to nephrologists is therefore warranted to facilitate prompt treatment.
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Affiliation(s)
- Stefania Drovandi
- Division of Nephrology, Dialysis, and Transplantation, IRCCS Istituto Giannina Gaslini, 16147 Genoa, Italy; (S.D.); (E.L.P.); (P.G.); (G.M.G.)
| | - Francesca Lugani
- Laboratory of Molecular Nephrology, IRCCS Istituto Giannina Gaslini, 16147 Genoa, Italy; (F.L.); (G.C.)
| | - Olivia Boyer
- PHP, Service de Néphrologie Pédiatrique, Institut Imagine, Centre de Référence MARHEA, Hôpital Universitaire Necker-Enfants Malades, Université Paris Cité, 75015 Paris, France; (O.B.); (A.H.)
| | - Edoardo La Porta
- Division of Nephrology, Dialysis, and Transplantation, IRCCS Istituto Giannina Gaslini, 16147 Genoa, Italy; (S.D.); (E.L.P.); (P.G.); (G.M.G.)
| | - Paolo Giordano
- Division of Nephrology, Dialysis, and Transplantation, IRCCS Istituto Giannina Gaslini, 16147 Genoa, Italy; (S.D.); (E.L.P.); (P.G.); (G.M.G.)
| | - Aurélie Hummel
- PHP, Service de Néphrologie Pédiatrique, Institut Imagine, Centre de Référence MARHEA, Hôpital Universitaire Necker-Enfants Malades, Université Paris Cité, 75015 Paris, France; (O.B.); (A.H.)
| | - Bertrand Knebelmann
- Nephrology Department, Reference Center for Inherited Kidney Diseases (MARHEA), APHP, Necker Hospital, Paris University, 75015 Paris, France; (B.K.); (J.C.)
| | - Joséphine Cornet
- Nephrology Department, Reference Center for Inherited Kidney Diseases (MARHEA), APHP, Necker Hospital, Paris University, 75015 Paris, France; (B.K.); (J.C.)
| | - Genevieve Baujat
- Reference Centre for Constitutional Bone Diseases, Laboratory of Osteochondrodysplasia, INSERM UMR 1163, Imagine Institute, Université de Paris, 75015 Paris, France;
| | - Beata S. Lipska-Ziętkiewicz
- Rare Diseases Centre, Medical University of Gdansk, 80-210 Gdansk, Poland;
- Department of Biology and Medical Genetics, Clinical Genetics Unit, Medical University of Gdansk, 80-210 Gdansk, Poland
| | - Gian Marco Ghiggeri
- Division of Nephrology, Dialysis, and Transplantation, IRCCS Istituto Giannina Gaslini, 16147 Genoa, Italy; (S.D.); (E.L.P.); (P.G.); (G.M.G.)
- Laboratory of Molecular Nephrology, IRCCS Istituto Giannina Gaslini, 16147 Genoa, Italy; (F.L.); (G.C.)
| | - Gianluca Caridi
- Laboratory of Molecular Nephrology, IRCCS Istituto Giannina Gaslini, 16147 Genoa, Italy; (F.L.); (G.C.)
| | - Andrea Angeletti
- Division of Nephrology, Dialysis, and Transplantation, IRCCS Istituto Giannina Gaslini, 16147 Genoa, Italy; (S.D.); (E.L.P.); (P.G.); (G.M.G.)
- Laboratory of Molecular Nephrology, IRCCS Istituto Giannina Gaslini, 16147 Genoa, Italy; (F.L.); (G.C.)
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Chen K, Zamariolli M, Soares MDFDF, Meloni VA, Melaragno MI. Multicentric Carpotarsal Osteolysis Syndrome in a Mother and Daughter with a MAFB Missense Variant and Natural History of the Disease. Mol Syndromol 2022; 13:50-55. [PMID: 35221875 PMCID: PMC8832254 DOI: 10.1159/000517348] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2021] [Accepted: 05/20/2021] [Indexed: 08/15/2023] Open
Abstract
Multicentric carpotarsal osteolysis syndrome (MCTO; MIM #166300) is a rare skeletal disorder characterized by osteolysis affecting particularly the carpal, metacarpal, and tarsal bones, although other bones might be involved. MCTO is an autosomal dominant disease caused by heterozygous variants in the MAFB gene, frequently misdiagnosed as juvenile rheumatoid arthritis due to similar clinical manifestations. This study reports the first Brazilian family diagnosed with MCTO with progressive osteolysis of the carpal and tarsal bones, presenting a c.161C>T (p.Ser54Leu) heterozygous variant in the MAFB gene, describing the clinical, radiological, and molecular findings, compared with literature data, and discussing the different clinical and molecular diagnosis, as well as the natural history of the disease. Since MCTO is a disorder with progressive symptoms, an early diagnosis is important to avoid unnecessary investigations and treatments and to provide the proper follow-up.
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Affiliation(s)
- Kelin Chen
- Department of Morphology and Genetics, Universidade Federal de São Paulo, São Paulo, Brazil
| | - Malú Zamariolli
- Department of Morphology and Genetics, Universidade Federal de São Paulo, São Paulo, Brazil
| | | | - Vera Ayres Meloni
- Department of Morphology and Genetics, Universidade Federal de São Paulo, São Paulo, Brazil
| | - Maria Isabel Melaragno
- Department of Morphology and Genetics, Universidade Federal de São Paulo, São Paulo, Brazil
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Multicentric Osteolysis, Nodulosis, and Arthropathy in two unrelated children with matrix metalloproteinase 2 variants: Genetic-skeletal correlations. Bone Rep 2021; 15:101106. [PMID: 34307793 PMCID: PMC8283316 DOI: 10.1016/j.bonr.2021.101106] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/10/2021] [Revised: 07/02/2021] [Accepted: 07/03/2021] [Indexed: 01/25/2023] Open
Abstract
Multicentric Osteolysis, Nodulosis, and Arthropathy (MONA) syndrome is a rare genetic skeletal dysplasia. Its diagnosis can be deceptively similar to childhood-onset genetic skeletal dysplasias and juvenile idiopathic arthritis. We aimed to report the syndrome’s clinical and radiologic features with emphasis on skeletal manifestations. And establish relevant phenotype-genotype correlations. We evaluated two boys, 4-and-7-years-old with MONA syndrome. Both patients had consanguineous parents. We verified the diagnosis by correlating the outcomes of clinical, radiologic and molecular analysis. We specifically evaluated the craniofacial morphology and clinical and radiographic skeletal abnormalities. We contextualized the resultant phenotype-genotype correlations to publications on MONA and its differential diagnosis. Skeletal manifestations were the presenting symptoms and mostly restricted to hands and feet in terms of fixed extension deformity of the metacarpophalangeal and flexion deformity of the interphalangeal joints with extension deformity of big toes. There were arthritic symptoms in the older patient especially of the wrists and minute pathologic fractures. The skeletal radiographs showed osteopenia/dysplastic changes of hands and feet. Both patients had variants in the matrix metalloproteinase2 gene which conformed to phenotype of previously reported literature in one patient while the other had a novel variant which conformed to MONA phenotype. Craniofacial abnormalities were present. However, minimal extra-skeletal manifestations. Overall, there is an emerging distinctive skeletal pattern of involvement in terms of both clinical and radiographic features. This includes age of onset and location of presenting skeletal manifestations, chronological order of joint affection, longitudinal disease progression, specifics of skeletal radiographic pathology and craniofacial features. Nevertheless, physicians are cautioned against differential diagnosis of similar genetic skeletal dysplasias and juvenile idiopathic arthritis. Presenting manifestations erupt simultaneously in the hands and feet. Skeletal manifestations proceed fairly rapidly in a distal-to-proximal fashion. Radiographic features are a mixture of osteopenia, joint destruction and fractures. Major disability may ensue in late childhood/adolescence, arthrogenic dysplasia Non-skeletal manifestations are variable in terms of age of appearance and frequency
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10
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Närhi A, Fernandes A, Toiviainen-Salo S, Harris J, McInerney-Leo A, Lazarus S, Avela K, Duncan EL. A family with partially penetrant multicentric carpotarsal osteolysis due to gonadal mosaicism: First reported case. Am J Med Genet A 2021; 185:2477-2481. [PMID: 33988298 DOI: 10.1002/ajmg.a.62257] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2021] [Revised: 03/17/2021] [Accepted: 04/10/2021] [Indexed: 01/30/2023]
Abstract
Multicentric carpotarsal osteolysis (MCTO) is an autosomal dominant condition characterized by carpal-tarsal abnormalities; over half of affected individuals also develop renal disease. MCTO is caused by mutations of MAFB; however, there is no clear phenotype-genotype correlation. We describe the first reported family of variable MCTO phenotype due to mosaicism: the proband had classical skeletal features and renal involvement due to focal segmental glomerulosclerosis (FSGS), and the father had profound renal impairment due to FSGS, necessitating kidney transplantation. Mosaicism was first suspected in this family due to unequal allele ratios in the sequencing chromatograph of the initial blood sample of proband's father and confirmed by sequencing DNA extracted from the father's hair, collected from different bodily parts. This case highlights the need for a high index of clinical suspicion to detect low-level parental mosaicism, as well as a potential role for MAFB mutation screening in individuals with isolated FSGS.
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Affiliation(s)
- Anu Närhi
- Department of Clinical Genetics, Helsinki University Hospital, Helenski, Finland
| | - Andrea Fernandes
- Department of Endocrinology and Diabetes, Royal Brisbane and Women's Hospital, Herston, Australia.,Faculty of Medicine, University of Queensland, Translational Research Institute, Woolloongabba, Australia.,Faculty of Medicine, Herston, University of Queensland, Herston, Australia
| | - Sanna Toiviainen-Salo
- Department of Radiology, New Children's Hospital, Helsinki University Hospital, Helenski, Finland
| | - Jessica Harris
- University of Queensland Diamantina Institute, University of Queensland, Translational Research Institute, Princess Alexandra Hospital, Woolloongabba, Australia
| | - Aideen McInerney-Leo
- Dermatology Research Centre, University of Queensland Diamantina Institute, University of Queensland, Woolloongabba, Australia
| | - Syndia Lazarus
- Department of Endocrinology and Diabetes, Royal Brisbane and Women's Hospital, Herston, Australia.,Faculty of Medicine, Herston, University of Queensland, Herston, Australia.,Department of Internal Medicine (Endocrinology), The Prince Charles Hospital, Chermside, Australia
| | - Kristiina Avela
- Department of Clinical Genetics, Helsinki University Hospital, Helenski, Finland
| | - Emma L Duncan
- Department of Twin Research and Genetic Epidemiology, School of Life Course Sciences, Faculty of Life Sciences and Medicine, King's College London, London, UK
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11
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Kaimori JY, Mori T, Namba-Hamano T, Morimoto T, Takuwa A, Motooka D, Okazaki A, Kobayashi K, Asahina Y, Kajimoto S, Doi Y, Oka T, Sakaguchi Y, Nakaya A, Isaka Y. Cyclosporine A Treatment of Proteinuria in a New Case of MAFB-Associated Glomerulopathy without Extrarenal Involvement: A Case Report. Nephron Clin Pract 2021; 145:445-450. [PMID: 33975323 DOI: 10.1159/000516248] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2020] [Accepted: 03/20/2021] [Indexed: 11/19/2022] Open
Abstract
The MAFB gene encodes an important basic leucine zipper transcription factor that functions in glomerular podocytes, macrophages, and osteoclasts. Recently, MAFB was identified as the gene that was responsible for causing nephropathy with focal segmental glomerulosclerosis (FSGS) with multicentric carpotarsal osteolysis (MCTO) or Duane retraction syndrome (DRS). Here, we describe a patient with nephropathy associated with FSGS who exhibited a novel stop-gain variant in the MAFB gene (NM_005461:c.590C>A (p.Ser197Ter)). The patient's father exhibited proteinuria with FSGS with possible DRS, whereas the patient exhibited nephropathy with FSGS and nearly normal eye movement and hearing function, as well as intact bone structure in the extremities. Conventional oral steroids or immunosuppressive drugs have not demonstrated effectiveness for patients with nephropathy who exhibit pathogenic variants in MAFB, except for a patient with nephropathy with FSGS and MCTO who experienced attenuated proteinuria within the subnephrotic range in response to cyclosporine A (CyA) treatment for at least 4 years. Thus, we attempted administration of CyA in our patient. Unexpectedly, the patient demonstrated good and rapid responses to CyA, including a partial reduction in proteinuria from approximately 2.0 g/g Cr to proteinuria within the subnephrotic range (0.27 g/g Cr) after 13 months of observation. Our findings suggest that CyA may be a suitable treatment option for patients with nephropathy with FSGS who exhibit pathogenic MAFB variants.
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Affiliation(s)
- Jun-Ya Kaimori
- Department of Inter-Organ Communication Research in Kidney Disease, Osaka University Graduate School of Medicine, Suita, Japan.,Department of Nephrology, Osaka University Graduate School of Medicine, Suita, Japan
| | - Tatsuhiko Mori
- Medical Education Center, Osaka Medical College, Takatsuki, Japan
| | - Tomoko Namba-Hamano
- Department of Nephrology, Osaka University Graduate School of Medicine, Suita, Japan
| | - Takeshi Morimoto
- Department of Ophthalmology, Osaka University Graduate School of Medicine, Suita, Japan
| | - Ayako Takuwa
- Genome Information Research Center, Research Institute for Microbial Diseases, Osaka University, Suita, Japan
| | - Daisuke Motooka
- Genome Information Research Center, Research Institute for Microbial Diseases, Osaka University, Suita, Japan
| | - Atsuko Okazaki
- Department of Genome Informatics, Osaka University Graduate School of Medicine, Suita, Japan.,Diagnostics and Therapeutics of Intractable Diseases, Intractable Disease Research Center, Graduate School of Medicine, Juntendo University, Tokyo, Japan
| | - Kaori Kobayashi
- Department of Genome Informatics, Osaka University Graduate School of Medicine, Suita, Japan.,Medical Solutions Division, NEC Corporation, Tokyo, Japan
| | - Yuta Asahina
- Department of Nephrology, Osaka University Graduate School of Medicine, Suita, Japan
| | - Sachio Kajimoto
- Department of Nephrology, Osaka University Graduate School of Medicine, Suita, Japan
| | - Yohei Doi
- Department of Nephrology, Osaka University Graduate School of Medicine, Suita, Japan
| | - Tatsufumi Oka
- Department of Nephrology, Osaka University Graduate School of Medicine, Suita, Japan
| | - Yusuke Sakaguchi
- Department of Inter-Organ Communication Research in Kidney Disease, Osaka University Graduate School of Medicine, Suita, Japan.,Department of Nephrology, Osaka University Graduate School of Medicine, Suita, Japan
| | - Akihiro Nakaya
- Department of Genome Informatics, Osaka University Graduate School of Medicine, Suita, Japan.,Laboratory of Genome Data Sciences, Graduate School of Frontier Science, The University of Tokyo, Kashiwa, Japan
| | - Yoshitaka Isaka
- Department of Nephrology, Osaka University Graduate School of Medicine, Suita, Japan
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12
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Han Y, Shao W, Zhong D, Ma C, Wei X, Ahmed A, Yu T, Jing W, Jing L. Zebrafish mafbb Mutants Display Osteoclast Over-Activation and Bone Deformity Resembling Osteolysis in MCTO Patients. Biomolecules 2021; 11:biom11030480. [PMID: 33806930 PMCID: PMC8004647 DOI: 10.3390/biom11030480] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2021] [Revised: 03/15/2021] [Accepted: 03/18/2021] [Indexed: 12/31/2022] Open
Abstract
Multicentric carpotarsal osteolysis (MCTO) is a rare skeletal dysplasia with osteolysis at the carpal and tarsal bones. Heterozygous missense mutations in the transcription factor MAFB are found in patients with MCTO. MAFB is reported to negatively regulate osteoclastogenesis in vitro. However, the in vivo function of MAFB and its relation to MCTO remains unknown. In this study, we generated zebrafish MAFB homolog mafbb mutant utilizing CRISPR/Cas9 technology. Mafbb deficient zebrafish demonstrated enhanced osteoclast cell differentiation and abnormal cartilage and bone development resembling MCTO patients. It is known that osteoclasts are hematopoietic cells derived from macrophages. Loss of mafbb caused selective expansion of definitive macrophages and myeloid cells, supporting that mafbb restricts myeloid differentiation in vivo. We also demonstrate that MAFB MCTO mutations failed to rescue the defective osteoclastogenesis in mafbb-/- embryos, but did not affect osteoclast cells in wild type embryos. The mechanism of MCTO mutations is likely haploinsufficiency. Zebrafish mafbb mutant provides a useful model to study the function of MAFB in osteoclastogenesis and the related MCTO disease.
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Affiliation(s)
- Yujie Han
- Engineering Research Center of Cell & Therapeutic Antibody, Ministry of Education, School of Pharmacy, Shanghai Jiao Tong University, Shanghai 200240, China; (Y.H.); (W.S.); (D.Z.); (C.M.); (X.W.); (A.A.)
| | - Weihao Shao
- Engineering Research Center of Cell & Therapeutic Antibody, Ministry of Education, School of Pharmacy, Shanghai Jiao Tong University, Shanghai 200240, China; (Y.H.); (W.S.); (D.Z.); (C.M.); (X.W.); (A.A.)
| | - Dan Zhong
- Engineering Research Center of Cell & Therapeutic Antibody, Ministry of Education, School of Pharmacy, Shanghai Jiao Tong University, Shanghai 200240, China; (Y.H.); (W.S.); (D.Z.); (C.M.); (X.W.); (A.A.)
| | - Cui Ma
- Engineering Research Center of Cell & Therapeutic Antibody, Ministry of Education, School of Pharmacy, Shanghai Jiao Tong University, Shanghai 200240, China; (Y.H.); (W.S.); (D.Z.); (C.M.); (X.W.); (A.A.)
| | - Xiaona Wei
- Engineering Research Center of Cell & Therapeutic Antibody, Ministry of Education, School of Pharmacy, Shanghai Jiao Tong University, Shanghai 200240, China; (Y.H.); (W.S.); (D.Z.); (C.M.); (X.W.); (A.A.)
| | - Abrar Ahmed
- Engineering Research Center of Cell & Therapeutic Antibody, Ministry of Education, School of Pharmacy, Shanghai Jiao Tong University, Shanghai 200240, China; (Y.H.); (W.S.); (D.Z.); (C.M.); (X.W.); (A.A.)
| | - Tingting Yu
- Shanghai Children’s Medical Center, Department of Medical Genetics and Molecular Diagnostic Laboratory, Shanghai Jiao Tong University School of Medicine, Shanghai 200127, China;
| | - Wei Jing
- Department of Hepatobiliary Pancreatic Surgery, Shanghai Changhai Hospital, Shanghai 200433, China
- Correspondence: (W.J.); (L.J.)
| | - Lili Jing
- Engineering Research Center of Cell & Therapeutic Antibody, Ministry of Education, School of Pharmacy, Shanghai Jiao Tong University, Shanghai 200240, China; (Y.H.); (W.S.); (D.Z.); (C.M.); (X.W.); (A.A.)
- Correspondence: (W.J.); (L.J.)
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13
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Regev R, Sochett EB, Elia Y, Laxer RM, Noone D, Whitney-Mahoney K, Filipowski K, Shamas A, Vali R. Multicentric carpotarsal osteolysis syndrome (MCTO) with generalized high bone turnover and high serum RANKL: Response to denosumab. Bone Rep 2021; 14:100747. [PMID: 33506078 PMCID: PMC7815641 DOI: 10.1016/j.bonr.2021.100747] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/29/2020] [Revised: 01/03/2021] [Accepted: 01/06/2021] [Indexed: 12/21/2022] Open
Abstract
MCTO is a rare disorder, caused by mutations in the MafB gene, a negative regulator of receptor activator of nuclear factor-кB ligand (RANKL). Manifestations include carpal and tarsal osteolysis and renal failure. Pathophysiology is poorly understood, and no effective treatment is available. In this case report we describe a patient with MCTO (MafB, mutation c.206C>T, p.Ser69Leu), diagnosed at the age of 5 years. At 7 years, skeletal survey showed diffuse osteopenia. BMD was mildly reduced, and bone turnover markers increased. He was treated with denosumab, a human monoclonal RANKL inhibitor for two years. Each injection was followed by a marked reduction in C-telopeptide (CTX). Following denosumab his BMD and bone symptoms improved and the osteolysis stabilized. At the age of 13 years, osteoporosis was diagnosed using high resolution peripheral quantitative computed tomography (HRpQCT) and serum RANKL was found to be markedly increased. This initial experience suggests that the associated osteoporosis may be ameliorated by denosumab, although further study will be needed to understand the appropriate dose, frequency, and the extent of efficacy. Monitoring of CTX and bone specific alkaline phosphatase will be especially useful in this regard. Further study in other MCTO patients is also needed to determine whether high bone turnover is specific to this mutation or more common than previously appreciated. We propose a model in which osteolysis in this condition is strongly associated with the systemic osteoporosis. MCTO (MafB gene mutation (c.206C>T,p.Ser69Leu) is associated with osteoporosis and very high levels of serum RANKL. Denosumab appears to ameliorate the osteoporosis. Further study is needed regarding the dose and frequency of injections. Examination of the frequency of osteoporosis and association with osteolysis is needed in MCTO
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Affiliation(s)
- Ravit Regev
- Division of Endocrinology, The Hospital for Sick Children, Toronto, ON, Canada.,Department of Diagnostic Imaging, The Hospital for Sick Children, Toronto, ON, Canada.,University of Toronto, Toronto, ON, Canada
| | - Etienne B Sochett
- Division of Endocrinology, The Hospital for Sick Children, Toronto, ON, Canada.,Department of Diagnostic Imaging, The Hospital for Sick Children, Toronto, ON, Canada.,University of Toronto, Toronto, ON, Canada
| | - Yesmino Elia
- Division of Endocrinology, The Hospital for Sick Children, Toronto, ON, Canada
| | - Ronald M Laxer
- Division of Rheumatology, The Hospital for Sick Children, Toronto, ON, Canada.,Department of Diagnostic Imaging, The Hospital for Sick Children, Toronto, ON, Canada.,University of Toronto, Toronto, ON, Canada
| | - Damien Noone
- Division of Nephrology, The Hospital for Sick Children, Toronto, ON, Canada.,Department of Diagnostic Imaging, The Hospital for Sick Children, Toronto, ON, Canada.,University of Toronto, Toronto, ON, Canada
| | | | - Kornelia Filipowski
- Division of Endocrinology, The Hospital for Sick Children, Toronto, ON, Canada
| | - Amer Shamas
- Department of Paediatrics, The Hospital for Sick Children, Toronto, ON, Canada.,Department of Diagnostic Imaging, The Hospital for Sick Children, Toronto, ON, Canada.,University of Toronto, Toronto, ON, Canada
| | - Reza Vali
- Department of Paediatrics, The Hospital for Sick Children, Toronto, ON, Canada.,Department of Diagnostic Imaging, The Hospital for Sick Children, Toronto, ON, Canada.,University of Toronto, Toronto, ON, Canada
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14
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Wu J, Wang L, Xu Y, Zhang Z, Yan X, An Y, Zhang Y, Tang X. Multicentric Carpo-Tarsal Osteolysis Syndrome Mimicking Juvenile Idiopathic Arthritis: Two Case Reports and Review of the Literature. Front Pediatr 2021; 9:745812. [PMID: 34722426 PMCID: PMC8554157 DOI: 10.3389/fped.2021.745812] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/22/2021] [Accepted: 09/15/2021] [Indexed: 11/13/2022] Open
Abstract
Multicentric carpo-tarsal osteolysis syndrome (MCTO) is a rare skeletal disorder commonly caused by MAF bZIP transcription factor B (MAFB) mutation. Clinically, it is characterized by aggressive osteolysis, which mainly affects the carpal tarsal bones, and is frequently associated with progressive nephropathy. Since the painful swelling and motion limitation on the wrists and/or ankles of MCTO mimics those of juvenile idiopathic arthritis (JIA), very often, MCTO is misdiagnosed as JIA. Here, we report two MCTO patients initially diagnosed with JIA but showed no response to treatment: P1, with a medical history of more than 10 years, was presented with a typical triad of arthritis-osteolysis-nephropathy; while P2 showed oligoarthritis. Gene tests were then taken and revealed a novel mutation, p.P63Q, and a previously reported conversion, p.S54L, in the MAFB gene. We also summarized the clinical and genetic features of a cohort containing 49 genetically confirmed MCTO patients. All 51 gene-confirmed MCTO cases (49 identified from the literature plus two patients identified herein) developed the disease during childhood. The median delay in diagnosis was 3.83 years (0-35 years). All cases presented bony lesions, and two-thirds had secondary renal lesions (32/48; three unknown), half of which (16/32) progressed into renal failure. Almost two-thirds (34/51), 75% (38/51), and 71% (36/51) of patients had no record of eye problems, facial abnormalities, and other manifestations. Most were misdiagnosed as JIA but didn't respond to treatment. Based on our experience, we suggest that clinicians should comprehensively evaluate the involvement of multiple systems in JIA patients, especially the kidney and eyes. And for JIA patients who underwent more than 3-month treatment with Bio-DMARD, genetic tests are recommended when they show little/no clinical and imaging changes, their high disease activity remains, and their disease activity remission is <50%, especially when combined with a triad of arthritis-osteolysis-nephropathy.
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Affiliation(s)
- Junfeng Wu
- Department of Rheumatology and Immunology, Children's Hospital of Chongqing Medical University, Chongqing, China.,National Clinical Research Center for Child Health and Disorders, Children's Hospital of Chongqing Medical University, Chongqing, China.,Ministry of Education Key Laboratory of Child Development and Disorders, Children's Hospital of Chongqing Medical University, Chongqing, China.,Chongqing Key Laboratory of Child Infection and Immunity, Children's Hospital of Chongqing Medical University, Chongqing, China.,Chongqing Key Laboratory of Pediatrics, Children's Hospital of Chongqing Medical University, Chongqing, China
| | - Li Wang
- Department of Rheumatology and Immunology, Children's Hospital of Chongqing Medical University, Chongqing, China.,National Clinical Research Center for Child Health and Disorders, Children's Hospital of Chongqing Medical University, Chongqing, China.,Ministry of Education Key Laboratory of Child Development and Disorders, Children's Hospital of Chongqing Medical University, Chongqing, China.,Chongqing Key Laboratory of Child Infection and Immunity, Children's Hospital of Chongqing Medical University, Chongqing, China.,Chongqing Key Laboratory of Pediatrics, Children's Hospital of Chongqing Medical University, Chongqing, China
| | - Ye Xu
- National Clinical Research Center for Child Health and Disorders, Children's Hospital of Chongqing Medical University, Chongqing, China.,Ministry of Education Key Laboratory of Child Development and Disorders, Children's Hospital of Chongqing Medical University, Chongqing, China.,Chongqing Key Laboratory of Child Infection and Immunity, Children's Hospital of Chongqing Medical University, Chongqing, China.,Chongqing Key Laboratory of Pediatrics, Children's Hospital of Chongqing Medical University, Chongqing, China.,Department of Radiology, Children's Hospital of Chongqing Medical University, Chongqing, China
| | - Zhiyong Zhang
- Department of Rheumatology and Immunology, Children's Hospital of Chongqing Medical University, Chongqing, China.,National Clinical Research Center for Child Health and Disorders, Children's Hospital of Chongqing Medical University, Chongqing, China.,Ministry of Education Key Laboratory of Child Development and Disorders, Children's Hospital of Chongqing Medical University, Chongqing, China.,Chongqing Key Laboratory of Child Infection and Immunity, Children's Hospital of Chongqing Medical University, Chongqing, China.,Chongqing Key Laboratory of Pediatrics, Children's Hospital of Chongqing Medical University, Chongqing, China
| | - Xin Yan
- Department of Rheumatology and Immunology, Children's Hospital of Chongqing Medical University, Chongqing, China.,National Clinical Research Center for Child Health and Disorders, Children's Hospital of Chongqing Medical University, Chongqing, China.,Ministry of Education Key Laboratory of Child Development and Disorders, Children's Hospital of Chongqing Medical University, Chongqing, China.,Chongqing Key Laboratory of Child Infection and Immunity, Children's Hospital of Chongqing Medical University, Chongqing, China.,Chongqing Key Laboratory of Pediatrics, Children's Hospital of Chongqing Medical University, Chongqing, China
| | - Yunfei An
- Department of Rheumatology and Immunology, Children's Hospital of Chongqing Medical University, Chongqing, China.,National Clinical Research Center for Child Health and Disorders, Children's Hospital of Chongqing Medical University, Chongqing, China.,Ministry of Education Key Laboratory of Child Development and Disorders, Children's Hospital of Chongqing Medical University, Chongqing, China.,Chongqing Key Laboratory of Child Infection and Immunity, Children's Hospital of Chongqing Medical University, Chongqing, China.,Chongqing Key Laboratory of Pediatrics, Children's Hospital of Chongqing Medical University, Chongqing, China
| | - Yu Zhang
- Department of Rheumatology and Immunology, Children's Hospital of Chongqing Medical University, Chongqing, China.,National Clinical Research Center for Child Health and Disorders, Children's Hospital of Chongqing Medical University, Chongqing, China.,Ministry of Education Key Laboratory of Child Development and Disorders, Children's Hospital of Chongqing Medical University, Chongqing, China.,Chongqing Key Laboratory of Child Infection and Immunity, Children's Hospital of Chongqing Medical University, Chongqing, China.,Chongqing Key Laboratory of Pediatrics, Children's Hospital of Chongqing Medical University, Chongqing, China
| | - Xuemei Tang
- Department of Rheumatology and Immunology, Children's Hospital of Chongqing Medical University, Chongqing, China.,National Clinical Research Center for Child Health and Disorders, Children's Hospital of Chongqing Medical University, Chongqing, China.,Ministry of Education Key Laboratory of Child Development and Disorders, Children's Hospital of Chongqing Medical University, Chongqing, China.,Chongqing Key Laboratory of Child Infection and Immunity, Children's Hospital of Chongqing Medical University, Chongqing, China.,Chongqing Key Laboratory of Pediatrics, Children's Hospital of Chongqing Medical University, Chongqing, China
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15
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Identification of a novel mutation in the MAFB gene in a pediatric patient with multicentric carpotarsal osteolysis syndrome using next-generation sequencing. Eur J Med Genet 2020; 63:103902. [PMID: 32278749 DOI: 10.1016/j.ejmg.2020.103902] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2019] [Revised: 03/02/2020] [Accepted: 03/09/2020] [Indexed: 11/21/2022]
Abstract
Multicentric carpotarsal osteolysis syndrome (MCTO) is a rare form of skeletal dysplasia characterized by progressive bone resorption, in the carpal and tarsal bones. Patients may develop chronic kidney disease, which eventually advances to end-stage renal disease (ESRD). Both sporadic and familial cases of autosomal-dominant inheritance are reported in literature. Here, we report a case of a 10.5-year-old boy who presented with CKD stage V, and who suffered from bone deformities and difficulty in walking at a younger age. He was diagnosed with MCTO and subjected to genetic analysis. We identified a novel mutation (NM_005461.5:c.173C > G) in the exon 1 of MAFB using next-generation sequencing. However, the mutation was not detected in his asymptomatic parents or siblings. This novel heterozygous mutation has not been reported previously. Our results show that the new mutation broadens the spectrum of disease phenotypes. This mutation may be helpful to confirm the potential cases of MCTO, which although can be identified through radiographic findings, stand a high chance of being misdiagnosed as rheumatological disease or as a metabolic bone disease secondary to CKD.
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