Autosomal dominant osteopetrosis type Ⅱ: 2 cases report and literature review / 中华内分泌代谢杂志

Osteosclerosis is a rare hereditary bone metabolic disease, characterized by increased bone mass and density caused by bone resorption disorders, and any abnormal mutation involving osteoclast maturation or function will lead to the occurrence of osteopetrosis. Clinically, the prevalence of autosomal dominant osteopetrosis type Ⅱ(ADO-Ⅱ) is higher than that of other types of osteopetrosis, which involves multiple systems such as endocrine, bone, blood, nerve, ear-nose-throat, and oral cavity. Disease progression is insidious and easily overlooked, and there is no standard treatment. This article summarizes the clinical characteristics, examination data, diagnosis and treatment process of the two patients, analyzes multi-system symptoms, pathogenesis and treatment principles of the disease to improve the management of patients with ADO-Ⅱ.

Osteopetrosis y fractura de cadera. Presentación de un caso y revisión de la literatura

La osteopetrosis constituye un conjunto de trastornos genéticos que determinan esclerosis del esqueleto. Se conoce también como enfermedad de Albers-Schonberg. Se trasmite tanto de forma autosómica dominante como recesiva. Su diagnóstico temprano permite tratar la patología de base y de manera precoz la fractura, para lograr la consolidación ósea e incorporar a los pacientes a su vida cotidiana con evolución favorable. Se presenta el caso de una paciente de 10 años de edad, de color de piel blanca, de sexo femenino, que desde los 4 años se seguía en consulta en el Complejo Científico Ortopédico Internacional Frank País García, donde fue diagnosticada de osteopetrosis. Seis años después se cayó de sus pies y presentó trauma en la cadera derecha. Comenzó con dolor intenso, inflamación y dificultad para la marcha. La paciente acudió al Hospital Pediátrico Universitario Paquito González Cueto de Cienfuegos donde fue valorada por los especialistas de pediatría, ortopedia y traumatología. Se le realizó radiografía de cadera donde se confirmó el diagnóstico de fractura de cadera derecha por lo que se ingresó para realizar tratamiento quirúrgico. Se presenta el caso con el objetivo de exponer el abordaje de este tipo de padecimiento y el método de tratamiento, motivados por su baja frecuencia de presentación.

Osteopetrosis constitutes a group of genetic disorders that determine skeletal sclerosis. It is also known as Albers-Schonberg disease. It is transmitted in both an autosomal dominant and recessive manner. Its early diagnosis makes it possible to treat the underlying pathology and the fracture early, in order to achieve bone consolidation and incorporate patients into their daily lives with a favorable evolution. We present the case of a 10-year-old female patient, white-skinned, who had been in consultation at the Frank País García International Orthopedic Scientific Complex since she was 4 years old, where she was diagnosed with osteopetrosis. Six years later, he fell off his feet and sustained trauma to his right hip. It started with severe pain, swelling and difficulty walking. The patient attended the Paquito González Cueto Pediatric University Hospital in Cienfuegos where she was evaluated by pediatric, orthopedic and traumatology specialists. A hip x-ray was performed where the diagnosis of right hip fracture was confirmed, for which he was admitted for surgical treatment. The case is presented with the objective of exposing the approach to this type of disease and the treatment method, motivated by its low frequency of presentation.

Generation and phenotype of myeloid cell specific Clcn7-mutation osteopetrosis mouse model / 中华内分泌代谢杂志

Objective:To construct a myeloid cell specific Clcn7-G763R mutant mouse model and characterize its phenotype.Methods:A mouse conditional knocked in p. G763R mutation in Clcn7 gene was constructed and bred with LysM cre mice to obtain osteopetrosis mice with myeloid cell specific Clcn7-G763R mutation. The differences of bone mass in mice with different genotypes were analyzed using Micro CT and the changes of histology were observed with HE staining. Osteoclasts were cultured and the expression levels of osteoclasts differentiation and maturation-related genes were detected by real-time PCR. The functions of osteoclasts were examined through bone resorption assay.Results:The body weight of homozygous mutant mice at 4 weeks old was reduced compared with the wild type mice [(12.000±1.666)g vs(15.630±2.314)g, P=0.021], with shorter femur length [(1.160±0.096)cm vs (1.300±0.082)cm, P=0.037]. Micro CT showed that bone mineral density of homozygous mutant mice was remarkably increased at 4 weeks old [(0.753±0.002)g/cm 3vs(0.143±0.034)g/cm 3, P=0.003], while bone mineral density of heterozygous mutant mice increased significantly at 8 weeks old [(0.236±0.021)g/cm 3vs(0.180±0.020)g/cm 3, P=0.030]. HE staining revealed increased trabecula bone volume in the mutant mice, especially in homozygous mutant mice with narrow bone marrow cavity and wider hypertrophic zone of chondrocytes. There was no significant difference in the number of osteoclasts between wild type mice and heterozygous mice in vitro( P=0.358), while total area of osteoclasts increased in heterozygous mutant mice [(3.590×10 6±0.911×10 6)μm 2vs(1.352×10 6±0.260×10 6)μm 2, P=0.043]. Impaired function of resorption was unveiled by bone resorption assay. There were no significant differences in the expressions of osteoclast differentiation and maturity-related genes including NFATc1, c-fos, Ctsk, and Acp5 between the two groups. Conclusion:A myeloid cell specific Clcn7-G763R mutation mice with impaired osteoclasts and increased bone mass is successfully constructed.

Enfermedad de Albera Shömberg. Reporte de un caso raro

La osteopetrosis agrupa un conjunto de enfermedades óseas caracterizadas por un aumento considerable de la densidad ósea. Conocida además como enfermedad marmórea o de Albers-Schönberg. Se presenta un caso de una mujer de 55 años de edad, color de piel blanca, femenina, con antecedentes patológicos familiares de hipertensión arterial y osteopetrosis. Los estudios radiológicos fueron positivos y confirmaron el diagnóstico de la Osteopetrosis marmórea en la forma benigna. Se realizan radiografías, observando múltiples lesiones óseas, se aplicaron pautas de tratamientos integradores funcionales, así como el uso de la M.N.T. Al término de la conclusión de ambas fases, el paciente ha disminuido el dolor, ha mejorado su estado psicológico, ha ganado en independencia, y por ende en su calidad de vida.

Osteopetrosis groups together a set of bone diseases characterized by a considerable increase in bone density. Also known as marble or Albers-Schönberg disease. We present a case of a 55-year-old woman, white skin color, female, with a family pathological history of arterial hypertension and osteopetrosis. Radiological studies were positive and confirmed the diagnosis of marble osteopetrosis in the benign form. X-rays were performed, observing multiple bone lesions, functional integrative treatment guidelines were applied, as well as the use of M.N.T. At the end of the conclusion of both phases, the patient has decreased pain, has improved his psychological state, has gained in independence, and therefore in his quality of life.

A osteopetrose agrupa um conjunto de doenças ósseas caracterizadas por um aumento considerável na densidade óssea. Também conhecida como mármore ou doença de Albers-Schönberg. Apresentamos um caso de uma mulher de 55 anos, cor de pele branca, feminina, com histórico patológico familiar de hipertensão arterial e osteopetrose. Os estudos radiológicos foram positivos e confirmaram o diagnóstico de osteopetrose de mármore na forma benigna. Foram realizados raios-X, observando múltiplas lesões ósseas, orientações de tratamento integrativo funcional, bem como o uso de M.N.T. Ao final da conclusão das duas fases, o paciente diminuiu a dor, melhorou seu estado psicológico, ganhou independência e, portanto, em sua qualidade de vida.

Osteopetrosis autosómica dominante benigna: Reporte de caso / Autosomal dominant osteopetrosis: Case report

La osteopetrosis es una enfermedad infrecuente, se caracteriza por el incremento de la densidad ósea observada en las radiografías, resultado de anormalidades en la diferen- ciación y función de los osteoclastos que les incapacita para la resorción ósea y cartilaginosa, formándose huesos más densos, pero más frágiles. Objetivo: describir la Osteopetrosis Auto- sómica Dominante mostrando nuestra experiencia el método de tratamiento. Con un amplio conocimiento de esta patología, los hallazgos radiográficos característicos y los manejos tera- péuticos adecuados podremos lograr un diagnóstico precoz certero y una mejor sobrevida de los pacientes. Reporte de caso: Paciente femenina de 13 años, con historia de fracturas espontáneas a repetición en los antebrazos principalmente, la madre niega antecedentes de trauma; asimismo refiere observar retraso en el crecimiento de la paciente, por lo cual acude al hospital regional de occidente, Quetzaltenango, Guatemala, para evaluación. Se le realizan radiografías en proyección anteroposterior (AP) y lateral de cráneo, de extremidades superio- res e inferiores y de columna dorsal evidenciando en las radiografías de cráneo aumento de la densidad ósea y aumento de grosor de la misma, en la columna dorsal se observó aumento de la esclerosis a nivel de las placas terminales superiores e inferiores de los cuerpos vertebrales, dando la típica apariencia de "vertebra en sándwich", signo patognomónico de esta enferme- dad. La paciente recibió tratamiento con prednisolona, vitamina D y calcio en dosis de acuerdo a las medidas antropométricas de la paciente y control médico por año para evaluar estado clínico...(AU)

Hematopoietic stem cell transplantation in a patient with osteopetrosis and mutation in CLCN7: long-term follow-up / Trasplante de células progenitoras hematopoyéticas en un paciente con osteopetrosis y mutación en CLCN7: seguimiento a largo plazo

Abstract Background: Osteopetrosis is a rare hereditary bone dysplasia characterized by insufficient osteoclast activity that results in increased bone mineral density. Hematopoietic stem cell transplantation (HSCT) can reverse skeletal abnormalities and restore hematopoiesis. Case report: We present the case of a 3-year and 2-month-old male patient with the diagnosis of osteopetrosis. The patient underwent allogeneic HSCT (Allo-HSCT) using 100% compatible bone marrow from a related donor and received a myeloablative conditioning regimen and a CD34 cell dose (4.7 × 107/kg). In the early post-transplant, frequent complications such as pneumonitis, hypercalcemia, and hyperphosphatemia ocurred. With a suitable granulocytic graft and chimerism of 100%, it was considered a successful transplant. However, the patient showed a delayed platelet graft treated with a platelet-stimulating factor for 6 months. The patient is currently disease-free, outpatient follow-up, with no data on graft-versus-host disease, and no progressive neurological damage. Conclusions: Osteopetrosis is a childhood disease that requires clinical suspicion and early diagnosis. HSCT is necessary at an early age to prevent disease progression and sensorineural, hematological, and endocrinological functions damage that can lead to death.

Resumen Introducción: La osteopetrosis es una displasia ósea hereditaria poco común, caracterizada por una actividad osteoclástica deficiente que aumenta la densidad mineral ósea. Se considera que el trasplante de células progenitoras hematopoyéticas (TCPH) puede revertir las anormalidades esqueléticas y restaurar la hematopoyesis. Caso clínico: Se presenta el caso de un paciente de sexo masculino, de 3 años y 2 meses de edad, con diagnóstico tardío de osteopetrosis. Se realizó un TCPH alogénico de donador relacionado 100% compatible con médula ósea. Se utilizaron un régimen de acondicionamiento mieloablativo y una dosis celular de CD34 de 4.7 × 107/kg de peso. En el postrasplante temprano, el paciente desarrolló complicaciones como neumonitis, hipercalcemia e hiperfosfatemia. Con un injerto granulocítico adecuado y quimerismo del 100% se consideró un trasplante exitoso. Sin embargo, el paciente presentó retraso en el injerto plaquetario, por lo que se administró factor estimulante de plaquetas por 6 meses. Actualmente el paciente se encuentra libre de enfermedad, en seguimiento ambulatorio, sin datos de enfermedad del injerto contra el hospedero y con pruebas de neurodesarrollo sin deterioro neurológico progresivo. Conclusiones: La osteopetrosis es una enfermedad infantil que requiere una sospecha clínica y un diagnóstico temprano, ya que es necesario un TCPH a corta edad como tratamiento para evitar la progresión de la enfermedad y el deterioro de las funciones neurosensoriales, hematológicas y endocrinológicas que puede derivar en la defunción del paciente.

SNX10 gene mutation in infantile malignant osteopetrosis: A case report and literature review / 中南大学学报(医学版)

A case of SNX10 gene mutation in a patient with infantile malignant osteopetrosis (IMO) was admitted to Department of Pediatrics, Third Xiangya Hospital, Central South University. The patient had the symptom of anemia, hepatosplenomegaly and growth retardation. The X-ray examination suggested extensive increase of bone density throughout the body, which was clinically diagnosed as IMO. The homozygous mutation of SNX10 gene c.61C>T was found via gene sequencing. We reviewed the relevant literatures and found that anemia, visual and hearing impairment, hepatosplenomegaly are the main clinical symptoms of IMO, SNX10 gene mutation is a rare cause of IMO, and hematopoietic stem cell transplantation is an effective treatment.

Osteopetrosis: presentación de un caso clínico / Osteopetrosis: presentation of a clinical case

La osteopetrosis, en particular la variante autosómica recesiva, es una patología con alta mortalidad de muy baja incidencia, lo cual conlleva al retraso de su diagnóstico perdiendo la posibilidad de un tratamiento oportuno para mejorar su pronóstico. Esta enfermedad se produce por una falla en la función o diferenciación osteoclástica con reabsorción ósea defectuosa.Presentamos un caso clínico motivados por la necesidad de agudizar su sospecha ante la presencia de los siguientes signos clínicos (hipocalcemia, alteraciones hematológicas, disfunción de pares craneales) y radiológicos característicos (engrosamiento cortical con colapso medular, esclerosis difusa afectando cráneo, huesos largos y columna, esclerosis focal, líneas escleróticas y radiolucidas que se alternan). Es necesario estar alertas a esta entidad para dar la posibilidad de un pronto estudio genético para arribar más rápido al transplante de medula ósea mejorando la sobrevida de estos pacientes

The osteopetrosis, including autosomal recessive variant is a disease with high mortality of very low incidence which leads to delay in diagnosis losing the possibility of early treatment to improve their prognosis. This disease is caused by a failure to function or osteoclastic differentiation with defective bone resorption. We report a case motivated by the need to sharpen their suspicion in the presence of the following clinical signs (hypocalcemia, blood disorders, cranial nerve dysfunction) and radiological characteristic (core collapse cortical thickening, diffuse sclerosis affecting skull, long bones and spine, focal sclerosis, sclerotic and radiolucent lines alternating).You need to be alert to this organization to give the possibility of a genetic study soon to arrive faster by improving bone marrow transplant survival in these patients

Pycnodysostosis: Anaesthetic Challenges

A rare autosomal recessive disorder Pycnodysostosis is to mutation of CTSK gene. This group of patients have fragile bone,craniofacial abnormalities with difficult airway. We are describing the anaesthetic management of a 12 yr male with pycnodosostosis for lower limb fracture fixation in combined spinal epidural anaesthesia.

Osteopetrosis Maligna Infantil: A propósito de un caso y revisión de la literatura / Child Maligine Osteopetrosis: A purpose of a case and review of the literature

Osteopetrosis comprende una serie de raras condiciones genéticas que produce un desequilibrio en el remodelado óseo debido a una actividad osteoclástica anormal. Reportamos una paciente mujer de 1 año 4 meses, diagnosticada de osteopetrosis maligna infantil neuropática mientras se investigaba la causa de palidez, abdomen distendido con circulación colateral y retardo en el crecimiento y de los hitos del desarrollo. Examen oftalmológico con retinopatía derecha. Radiografías del esqueleto revelaron una hiperdensidad ósea generalizada. Aspirado de medula ósea mostró hipercelularidad con la serie eritroide hiperplásica, serie blanca y megacariocítica normal. Diagnóstico fue confirmado por características clínicas y radiológicas. La paciente recibió tratamiento de soporte. Aunque el diagnostico de osteopetrosis maligna infantil es sencillo este a menudo se retrasa por la infrecuencia de la enfermedad y la falta de sospecha clínica, un diagnóstico oportuno y un tratamiento de trasplante de medula ósea son el enfoque curativo para una enfermedad de pobre pronóstico.

Osteopetrosis comprises a series of rare genetic conditions that produce an imbalance in bone remodeling due to abnormal osteoclastic activity. We report a female patient 1 year 4 months, diagnosed with malignant osteopetrosis neuropathic child while causing paleness, distended abdomen with collateral circulation and growth retardation and developmental milestones are investigating. Examination right eye with retinopathy. Skeletal x-rays revealed a generalized bone hyperdensity. She bone marrow aspirate showed hypercellularity with hyperplastic erythroid, megakaryocytic normal white series. Diagnosis was confirmed by clinical and radiological features. The patient received supportive care. While the diagnosis is simple OPAR this is often delayed by the rarity of the disease and the lack of clinical suspicion, early diagnosis and treatment of bone marrow transplant is curative approach to a disease of poor prognosis

Osteopetrosis infantil maligna / Malignant Infantile osteopetrosis

INTRODUCCIÓN: Osteopetrosis Infantil Maligna (OIM) es un grave e inusual desorden genético debi do a una actividad osteoclástica anormal. OBJETIVO: Reportar lactante en quien se documentó una Osteopetrosis Infantil Maligna, revisando aspectos diagnósticos y terapéuticos más relevantes. CASO CLÍNICO: Reportamos un lactante de 10 meses de sexo masculino en quien se confirmó OIM tras presentar plaquetopenia y visceromegalias. En su historial destacó ser primer hijo de padres no consanguíneos, y entre sus hallazgos presentó hepatoesplenomegalia, plaquetopenia y anemia graves, compromiso sensorial visual y auditivo e infecciones a repetición. El diagnóstico fue confirmado mediante estudio genético, el cual identificó 2 mutaciones heterocigotas en el gen TCIRG1. Se rea lizó trasplante de precursores hematopoyéticos, sin haber presentado recuperación hematológica, falleciendo por enfermedad veno oclusiva. DISCUSIÓN: La OIM es una enfermedad inusual, grave y de inicio temprano, siendo necesario un elevado índice de sospecha ante hepatoesplenomegalia y falla medular. El diagnóstico temprano y el trasplante de precursores hematopoyéticos son las únicas intervenciones potencialmente curativas de esta entidad letal.

INTRODUCCIÓN: Malignant Infantile Osteopetrosis (MIOP) is a rare and severe genetic disorder due to abnormal osteoclast activity. OBJECTIVE: To report an infant who presented Malignant Infantile Osteopetrosis, reviewing the most relevant diagnostic and therapeutic aspects. CLINICAL CASE: A ten- month-old male infant with diagnosis of MIOP confirmed after presenting thrombocytopenia and visceromegaly. He was the first child of non-consanguineous parents, and among the findings, he presented severe hepatosplenomegaly, thrombocytopenia, and anemia; visual and hearing impairment, and repeated infections. The diagnosis was confirmed by genetic study, which identified two heterozygous mutations in the TCIRG1 gene. Hematopoietic stem cells were transplanted without hematological recovery. The patient died due to occlusive venous disease. DISCUSSION: MIOP is a rare, severe, and early-onset disease, with a high rate of suspicion necessary in the presence of hepatosplenomegaly and bone marrow failure. Early diagnosis and hematopoietic stem cells transplanta tion are the only potentially therapeutic interventions of this lethal entity.

Remodelling of Humeral Fracture in a Child with Osteopetrosis Tarda following Conservative Management -A 7-year Follow-up: A Case Report

@#Osteopetrosis (OP) is a rare hereditary sclerosing bone dysplasia characterised by generalised hard and brittle bone secondary to defective osteoclastic function. Osteopetrotic bone is brittle, thus these subjects are prone to frequent fractures, particularly of the long bones. Due to defective osteoclastic function, remodeling is also defective in OP. This report is a case of humeral fracture in a 9 years old girl who was followed seven years. The fracture had remodeled totally similar to healthy bone at the final follow-up. Conservative treatment should be kept in mind in the management of fractures in children with OP, and fractures within acceptable angulations and/or translations should be treated conservatively without hesitation.

Lessons Learned from Long-Term Management of Hip Fracture in Patients with Osteopetrosis: A Report of Nine Hips in Five Patients

BACKGROUND: Treating patients with osteopetrosis is very challenging even in very skilled surgeons with many experiences. We present an account of 5 patients treated for hip fracture related problems occurring throughout their life due to this disease. Difficulties encountered during their treatment prompted us to present some general management principles. METHODS: From January 2003 to December 2016, 5 patients with osteopetrosis (9 hips; 3 men, 2 women), who underwent operative or conservative treatment were retrospectively reviewed. We evaluated their clinical features and rate of union, malunion and post-operative infection. RESULTS: Four of 5 patients (80%) suffered bilateral fracture, and 8 of 9 fractures (89%) are transverse and occurred at subtrochanteric area resulted from minor trauma. Among 9 hips, surgery was performed in seven hips. Nonunion were found in 3 hips (33%), malunion in 1 hip (11%) and oteomyelitis was developed in 2 hips (22%) at a median of 8.1 years. CONCLUSIONS: Clinical features of hip fracture in osteopetrosis are very similar to atypical subtrochanteric femoral fractures. Patients should be informed of the possibilities of several anticipated complications including the risk of nonunion and infection after surgery.

Autosomal recessive osteopetrosis type I: description of pathogenic variant of TCIRG1 gene / Osteopetrosis infantil maligna: descripción de una nueva mutación patogénica de TCIRG1

Abstract Background: Autosomal malignant osteopetrosis is a rare condition arising from dysfunction of bone-resorbing osteoclasts, in which diagnosis requires a high suspicion index. Treatment of choice is allogeneic stem cell transplantation. Best outcomes occur if the procedure is carried out before damage to cranial nerves ensues; nonetheless, patients improve their clinical condition. Case report: An 8-month-old infant was referred for hematology consultation for cytopenias, hepatomegaly, and growth failure. Autosomal malignant osteopetrosis was diagnosed on the basis of physical findings, alteration in calcium and phosphorus metabolism, and hyperdensity of bone. DNA was obtained from the patient and parents; compound heterozygosity of the TCIRG1 gene with a previously non-described deletion (c.1809_1818del) was identified. Conclusions: A new pathogenic mutation of TCIRG1 was identified in a Mexican osteopetrotic patient. Hematopoietic stem cell transplantation was offered as the best available treatment but declined by the parents. An early recognition and wider access to this procedure should be implemented.

Resumen Introducción: La osteopetrosis infantil maligna es una condición rara cuyo origen es la deficiente reabsorción ósea por parte de los osteoclastos. Su diagnóstico requiere un alto índice de sospecha. El tratamiento de elección es el trasplante alogénico de células hematopoyéticas. Los mejores desenlaces ocurren si el procedimiento se lleva a cabo antes de que ocurra daño a los nervios craneales. Caso clínico: Paciente masculino de 8 meses de edad fue referido a la consulta de hematología por citopenias, hepatomegalia y falla para crecer. Se diagnosticó osteopetrosis infantil maligna basándose en los hallazgos de la exploración física, la alteración del metabolismo del calcio y el fósforo y la hiperdensidad del hueso. Se obtuvo ADN del paciente y ambos padres; se demostró un heterocigosidad compuesta del gen TCIRG1 con una deleción (c.1809_1818del) no descrita previamente. Conclusiones: Una nueva mutación patogénica de TCIRG1 se identificó en un paciente mexicano con osteopetrosis. Se ofreció trasplante de células progenitoras hematopoyéticas como el mejor tratamiento disponible, pero fue rechazado por los padres. Se necesita un reconocimiento temprano y la implementación del acceso generalizado a este procedimiento.

Autosomal dominant osteopetrosis type II

Osteopetrosis ("marble bone disease") is a descriptive term that refers to a group of rare, heritable disorders of the skeleton characterized by increased bone density on radiographs. The overall incidence of these conditions is difficult to estimate but autosomal recessive osteopetrosis (ARO) has an incidence of 1 in 250,000 births, and autosomal dominant osteopetrosis (ADO) has an incidence of 1 in 20,000 births. Osteopetrotic conditions vary greatly in their presentation and severity, ranging from neonatal onset with life-threatening complications such as bone marrow failure (e.g. classic or "malignant" ARO), to the incidental finding of osteopetrosis on radiographs (e.g. osteopoikilosis). Classic ARO is characterised by fractures, short stature, compressive neuropathies, hypocalcaemia with attendant tetanic seizures, and life-threatening pancytopaenia. The presence of primary neurodegeneration, mental retardation, skin and immune system involvement, or renal tubular acidosis may point to rarer osteopetrosis variants, whereas onset of primarily skeletal manifestations such as fractures and osteomyelitis in late childhood or adolescence is typical of ADO. Osteopetrosis is caused by failure of osteoclast development or function and mutations in at least 10 genes have been identified as causative in humans, accounting for 70% of all cases. These conditions can be inherited as autosomal recessive, dominant or X linked traits with the most severe forms being autosomal recessive. Diagnosis is largely based on clinical and radiographic evaluation, confirmed by gene testing where applicable, and paves the way to understanding natural history, specific treatment where available, counselling regarding recurrence risks, and prenatal diagnosis in severe forms. Treatment of osteopetrotic conditions is largely symptomatic, although haematopoietic stem cell transplantation is employed for the most severe forms associated with bone marrow failure and currently offers the best chance of longer term survival in this group. The severe infantile forms of osteopetrosis are associated with diminished life expectancy, with most untreated children dying in the first decade as a complication of bone marrow suppression. Life expectancy in the adult onset forms is normal.

Genetic Analysis of CLCN7 in an Old Female Patient with Type II Autosomal Dominant Osteopetrosis

BACKGROUND: Type II autosomal dominant osteopetrosis (ADO II) is a rare genetically heterogeneous disorder characterized by osteosclerosis and increased bone mass, predominantly involving spine, pelvis, and skull. It is closely related to functional defect of osteoclasts caused by chloride voltage-gated channel 7 (CLCN7) gene mutations. In this study, we aimed to identify the pathogenic mutation in a Korean patient with ADO II using whole exome sequencing. METHODS: We evaluated the clinical, biochemical, and radiographic analysis of a 68-year-old woman with ADO II. We also performed whole exome sequencing to identify pathogenic mutation of a rare genetic disorder of the skeleton. Moreover, a polymorphism phenotyping program, Polymorphism Phenotyping v2 (PolyPhen-2), was used to assess the effect of the identified mutation on protein function. RESULTS: Whole exome sequencing using peripheral leukocytes revealed a heterozygous c.296A>G missense mutation in the CLCN7 gene. The mutation was also confirmed using Sanger sequencing. The mutation c.296A>G was regarded to have a pathogenic effect by PolyPhen-2 software. CONCLUSION: We detect a heterozygous mutation in CLCN7 gene of a patient with ADO II, which is the first report in Korea. Our present findings suggest that symptoms and signs of ADO II patient having a c.296A>G mutation in CLCN7 may appear at a very late age. The present study would also enrich the database of CLCN7 mutations and improve our understanding of ADO II.

Application of whole exome sequencing technique for the pathogenic gene screening of rare osteopetrosis / 国际检验医学杂志

Objective To screen the pathogenic gene of osteopetrosis to provide reference for its genetic di-agnosis and prognosis .Methods The clinical data and peripheral blood samples were collected from the pa-tients with osteopetrosis ,DNA was extracted ,the whole exome sequencing library was built ,then the high throughput detection was performed and the pathogenic gene was screened by combining with the bioinformat-ics technology .Results The whole exomes in 2 cases of osteopetrosis were analyzed ,the average sequencing depth of the two samples were 169 .38X and 231 .06X respectively ,in which the case 1 carried rare mutation TCIRG1(c .1305+2T>C) ,TCIRG1(c .2008C> T ) and CLCN7(c .1116C> T );the case 2 carried a rare muta-tion CLCN7(c .857G>A ) .T he bioinformatics analysis indicated that the rare mutations carried by these cases all had different degrees of influence on the structure and function of gene products .Conclusion The whole exome sequencing can once screen the know n pathogenic mutations of osteopetrosis ,is an effective tool for pathogenic mutation screening of osteopetrosis ,the clinical disease in 2 cases of osteopetrosis may be closely related with the patient′s carrying TCIRG1 and CLCN7 mutation .

Analysis on 4 cases of polycythemia vera transforming to acute myeloid leukemia / 重庆医学

Objective To explore the clinical characteristics,diagnosis and treatment of polycythemia vera(PV) transforming to acute myeloid leukemia(AML).Methods The clinical features and process of diagnosis and treatment in 4 cases of PV transforming to AML were analyzed.Results The case 1 had 10 years history of PV,after experiencing PV,had myelofibrosis and transformed to AML at the end stage of natural disease course;the case 2 had 7 years history of PV,orally took hydroxyurea(HU) treatment in recent 2 years and transformed to AML at present,his chromosome karyotype analysis showed 46,XY,del(7)(q31q36),del (18) (q22)[10],which was considered as treatment-related AML;the case 3 and 4 orally took H U for a long time after diagnosing HU,and respectively turned into AML during the pathologic polyemia stage after 6 and 7 years.Conclusion PV can be transformed to AML,the safety of HU in treatment should by paid attention to.

Dental Management in a Patient with Infantile Osteopetrosis : A Case Report with a 7-Year follow-up / 대한소아치과학회지

Osteopetrosis is characterized by impaired osteoclast function and increased bone density. Infantile osteopetrosis is a severe form of the disease and has characteristics such as diffusely sclerotic skeleton, pancytopenia, cranial nerve entrapment, infection susceptibility, and abnormal craniofacial appearance. Patients with infantile osteopetrosis often experience developmental delay, and may have a short life span.A 14-month-old girl with osteopetrosis presented to the department of pediatric dentistry. Incipient caries on deciduous incisors were observed. The patient revisited 4 years of age. Besides medical problems, oral complications such as growth retardation, narrow upper arch, crowding, dental caries, and abnormal tooth development were observed. After consultation with her pediatrician, dental treatments were performed on the deciduous molars under sedation after a prophylactic antibiotic injection. At a periodic follow-up, multiple deciduous teeth were treated and extracted, and oral-rehabilitation with a removable partial denture was initiated.Patient with osteopetrosis are highly susceptible to infection because of their compromised immune system and problems associated with wound healing that lead to osteomyelitis or sepsis development.Active participation in dental care for sugar intake management and proper oral hygiene are obligatory.

Osteopetrosis con afectación de cuatro nervios craneales / Osteopetrosis with damage of four cranial nerves

Introducción: la osteopetrosis se caracteriza por una insuficiente resorción ósea, como consecuencia de un trastorno de la actividad de los osteoclastos, y provoca aumento de la densidad ósea, es decir, un hueso altamente calcificado, pero muy frágil; hay fracaso del potencial de la médula ósea, desencadenando la hematopoyesis secundaria, con manifestaciones de visceromegalia y pancitopenia. El engrosamiento de los huesos provoca estrechamiento de los forámenes del cráneo, por donde emergen los nervios craneales, se comprimen y provoca manifestaciones clínicas secundariamente. Presentación del caso: paciente femenina que a los 3 años de edad manifestó nistagmus horizontal, paresia de nervio motor ocular externo derecho, pérdida de respuesta al estímulo auditivo bilateral, parálisis facial periférica izquierda y atrofia bilateral del nervio óptico; radiológicamente mostró aumento de la densidad ósea, con importante engrosamiento de la base de cráneo y huesos largos. Conclusiones: el diagnóstico de la osteopetrosis es sencillo y depende principalmente de los estudios radiológicos, pero pasa inadvertido por su baja frecuencia y falta de sospecha clínica. El diagnóstico temprano del compromiso de múltiples nervios craneales, la atención multidisciplinaria y su tratamiento oportuno, contribuye a su mejor evolución(AU)

Introduction: osteopetrosis is characterized by insufficient bone resorption as a consequence of a disorder in the osteoclast activity and brings about increased bone density, that is, a highly calcified bone but very fragile. There is failed potential of the bone marrow, thus unleashing secondary hematopoiesis with visceromegalia and pancitopenia manifestations. The bone thickening provokes narrowing in cranium foramens where the cranial nerves pass, they compressed and cause secondary clinical manifestations. Case report: a female patient aged 3 years showed horizontal nistagmus, paresia in the right external ocular motor nerve, loss of response to bilateral hearing stimulus, peripheral facial palsy and bilateral atrophy of the optical nerve. The radiological tests showed increased bone density with significant thickening of the skull base and long bones. Conclusions: the diagnosis of osteopetrosis is simple and mainly depends on the radiological studies, but it is unnoticed because of its low frequency and the inexistent clinical suspicion. The early diagnosis of the damage of several cranial nerves, the multidisciplinary care and timely treatment may contribute to better evolution(AU)