Diagnostic challenges in hypophosphatasia in adult patients / Desafios do diagnóstico da hipofosfatasia em adultos

Introdução: Hipofosfatasia é um distúrbio metabólico que afeta a mineralização óssea e dentária, causada por mutações no gene ALPL, levando à deficiência enzimática da fosfatase alcalina tecido não-específica. A forma adulta caracteriza-se por fraturas atípicas do fêmur, osteomalácia, osteoporose, grave osteoartropatia, condrocalcinose e artralgia. Objetivo: Demonstrar desafios diagnósticos relacionados à hipofosfatasia através do relato de dois casos. Paciente 1: feminino, 59 anos, encaminhada para avaliação clínica devido às fraturas patológicas de difícil consolidação e osteoporose generalizada de causa genética. Relata perda dentária precoce da arcada superior, fraturas na coluna, em ombro esquerdo e no fêmur. Atualmente, queixa-se de dor crônica intensa, com uso de múltiplos medicamentos. Achados clínicos, laboratoriais e radiológicos foram compatíveis com o diagnóstico de hipofosfatasia. Paciente 2: masculino, 31 anos, filho da paciente 1, encaminhado para avaliação clínica por fratura patológica precoce em fêmur esquerdo e osteoporose não esclarecida. Atualmente relata dor e claudicação importante em membro inferior esquerdo, associado à lombalgia crônica. Confirmação do diagnóstico de hipofosfatasia por exames laboratoriais e radiológicos e sequenciamento do gene ALPL, aliados ao diagnóstico da sua genitora. Discussão: Hipofosfatasia é uma doença rara de herança autossômica dominante e recessiva. Pacientes acometidos apresentam fraturas constantes, densidade mineral óssea baixa, cicatrização óssea deficitária. É comum a hipofosfatasia ser diagnosticada erroneamente como osteopenia e/ou osteoporose primária, acarretando prejuízos ao paciente. Ressalta-se a importância da história clínica completa e dos antecedentes familiares a fim de se obter um diagnóstico precoce, garantindo, por sua vez, o adequado acompanhamento e manejo terapêutico (AU)

Introduction: hypophosphatasia is a metabolic disorder affecting bone and tooth mineralization, caused by mutations in the ALPL gene leading to enzymatic deficiency of tissue non-specific alkaline phosphatase. The adult form is characterized by atypical femur fractures, osteomalacia, osteoporosis, severe osteoarthropathy, chondrocalcinosis, and arthralgia. Objective: to demonstrate diagnostic challenges related to hypophosphatasia through the report of two cases. Patient 1: female, 59 years old, referred for clinical evaluation due to pathological fractures of difficult consolidation and generalized osteoporosis of genetic cause. She reports early tooth loss in the upper arch, fractures in the spine, left shoulder and femur. Currently, he complains of severe chronic pain, with use of multiple medications. Clinical, laboratory, and radiological findings were compatible with the diagnosis of hypophosphatasia. Patient 2:male, 31 years old, son of patient 1, referred for clinical evaluation due to an early pathological fracture in the left femur and unclear osteoporosis. He currently reports pain and significant claudication in the left lower limb, associated with chronic low back pain. Confirmation of the diagnosis of hypophasatasia by laboratory and radiological tests and sequencing of the ALPL gene combined with the diagnosis of his mother. Discussion: hypophosphatasia is a rare disease of autosomal dominant and recessive inheritance. Affected patients have constant fractures, low bone mineral density, and impaired bone healing. It is common for hypophosphatasia to be misdiagnosed as osteopenia and/or primary osteoporosis, which can be harmful to the patient. The importance of a complete clinical history and family history is emphasized in order to obtain an early diagnosis, ensuring adequate follow-up and therapeutic management (AU)

Un caso de hipofosfatasia perinatal grave con una mutación novedosa / Severe perinatal hypophosphatasia case with a novel mutation

La hipofosfatasia es un trastorno hereditario raro causado por mutaciones en el gen ALPL. Causa defectos en la mineralización ósea y dental, función respiratoria anormal, convulsiones, hipotonía, dolor óseo y nefrocalcinosis. Las formas clínicas se reconocen según la edad al diagnóstico y la gravedad. Presentamos el caso de una lactante con fontanela anterior agrandada, bóveda craneal blanda, fracturas, dificultad respiratoria y convulsiones. El análisis bioquímico mostró hipercalcemia, fosfato sérico normal y fosfatasa alcalina sérica baja. La radiografía mostró hipomineralización, fracturas y callos. La concentración plasmática de piridoxal-5'-fosfato era de 762 mg/l (intervalo normal: 5-50) y la concentración de fosfoetanolamina en orina era de 1015 mmol/l (intervalo normal: 15-341). El análisis del gen ALPL mostró dos mutaciones heterocigotas compuestas, una de las cuales es novedosa. El diagnóstico y tratamiento tempranos de la hipofosfatasia perinatal podría mejorar los resultados y tener un impacto positivo en la sobrevida.

Hypophosphatasia (HPP) is a rare inherited disorder caused by mutations in the ALPL gene. Mineralization defect in bones and teeth, abnormal respiratory function, seizures, hypotonia, bone pain, and nephrocalcinosis can be observed. Clinical forms are usually recognized based on age at diagnosis and severity of features. We present an infant with an enlarged anterior fontanelle, soft calvarium, fractures, respiratory distress, and seizures. Biochemical analysis showed hypercalcemia, normal serum phosphate, and low serum alkaline phosphatase (ALP) levels. X-ray showed hypomineralization, fractures, and callus formations. Plasma pyridoxal 5'-phosphate (PLP) was 762 mg/L (NV : 5-50) and urine phosphoethanolamine (PEA) was 1015 mmol/L (NV : 15-341) and ALPL gene analysis showed two compound heterozygous mutations, one of which is a novel one. Early diagnosis and treatment of perinatal HPP may improve outcomes and might have a positive impact on survival.

Desafios do diagnóstico da hipofosfatasia em adultos / Diagnostic challenges in hypophosphatasia in adult patients

RESUMO:Introdução: Hipofosfatasia é um distúrbio metabólico que afeta a mineralização óssea e dentária, causada por mutações no gene ALPL, levando à deficiência enzimática da fosfatase alcalina tecido não-específica. A forma adulta caracteriza-se por fraturas atípicas do fêmur, osteomalácia, osteoporose, grave osteoartropatia, condrocalcinose e artralgia. Objetivo: Demonstrar desafios diagnósticos relacionados à hipofosfatasia através do relato de dois casos. Paciente 1: feminino, 59 anos, encaminhada para avaliação clínica devido às fraturas patológicas de difícil consolidação e osteoporose generalizada de causa genética. Relata perda dentária precoce da arcada superior, fraturas na coluna, em ombro esquerdo e no fêmur. Atualmente, queixa-se de dor crônica intensa, com uso de múltiplos medicamentos. Achados clínicos, laboratoriais e radiológicos foram compatíveis com o diagnóstico de hipofosfatasia. Paciente 2: masculino, 31 anos, filho da paciente 1, encaminhado para avaliação clínica por fratura patológica precoce em fêmur esquerdo e osteoporose não esclarecida. Atualmente relata dor e claudicação importante em membro inferior esquerdo, associado à lombalgia crônica. Confirmação do diagnóstico de hipofosfatasia por exames laboratoriais e radiológicos e sequenciamento do gene ALPL, aliados ao diagnóstico da sua genitora. Discussão: Hipofosfatasia é uma doença rara de herança autossômica dominante e recessiva. Pacientes acometidos apresentam fraturas constantes, densidade mineral óssea baixa, cicatrização óssea deficitária. É comum a hipofosfatasia ser diagnosticada erroneamente como osteopenia e/ou osteoporose primária, acarretando prejuízos ao paciente. Ressalta-se a importância da história clínica completa e dos antecedentes familiares a fim de se obter um diagnóstico precoce, garantindo, por sua vez, o adequado acompanhamento e manejo terapêutico. (AU)

ABSTRACT: Introduction: hypophosphatasia is a metabolic disorder affecting bone and tooth mineralization, caused by mutations in the ALPL gene leading to enzymatic deficiency of tissue non-specific alkaline phosphatase. The adult form is characterized by atypical femur fractures, osteomalacia, osteoporosis, severe osteoarthropathy, chondrocalcinosis, and arthralgia. Objective: to demonstrate diagnostic challenges related to hypophosphatasia through the report of two cases. Patient 1: female, 59 years old, referred for clinical evaluation due to pathological fractures of difficult consolidation and generalized osteoporosis of genetic cause. She reports early tooth loss in the upper arch, fractures in the spine, left shoulder and femur. Currently, he complains of severe chronic pain, with use of multiple medications. Clinical, laboratory, and radiological findings were compatible with the diagnosis of hypophosphatasia. Patient 2:male, 31 years old, son of patient 1, referred for clinical evaluation due to an early pathological fracture in the left femur and unclear osteoporosis. He currently reports pain and significant claudication in the left lower limb, associated with chronic low back pain. Confirmation of the diagnosis of hypophasatasia by laboratory and radiological tests and sequencing of the ALPL gene combined with the diagnosis of his mother. Discussion: hypophosphatasia is a rare disease of autosomal dominant and recessive inheritance. Affected patients have constant fractures, low bone mineral density, and impaired bone healing. It is common for hypophosphatasia to be misdiagnosed as osteopenia and/or primary osteoporosis, which can be harmful to the patient. The importance of a complete clinical history and family history is emphasized in order to obtain an early diagnosis, ensuring adequate follow-up and therapeutic management. (AU)

Active search of adult patients with persistently low serum alkaline phosphatase levels for the diagnosis of hypophosphatasia

ABSTRACT Objectives: Alkaline phosphatase (ALP) is the main laboratory marker of hypophosphatasia (HPP), a rare disease unknown to most physicians. The prevalence of HPP has been widely discussed in the literature due to the diverse phenotypes of HPP. The purpose of this study was to search for patients with hypophosphatasemia based on previous biochemistry tests and reevaluate them to confirm the diagnosis of HPP. Subjects and methods: A total of 289,247 biochemical tests for ALP in adults were performed from 2015 to 2019 in two tertiary hospitals in Rio de Janeiro were reviewed (Clementino Fraga Filho University Hospital - HUCFF - and Bonsucesso Federal Hospital - BFH). Results: A total of 1,049 patients were identified with ALP levels below 40 U/L, and 410 patients had hypophosphatasemia confirmed by at least two exams. After the active search of medical reports and/or interviews based on structured questionnaires, 398 subjects were excluded due to secondary causes of reduced ALP. The remaining 12 patients were invited to attend the medical consultation at HUCFF, accompanied by at least one first-degree relative. None of the patients or their relatives had a history or clinical manifestations consistent with HPP. Serum ALP was within reference values in all relatives, but persistently low in further laboratory evaluation in all the 12 patients, in whom secondary causes were ruled out. Thus, we cannot exclude the possibility that they might carry the mutations associated with HPP. Conclusion: Further image evaluations and genetic testing would be appropriate to confirm this asymptomatic adult form of HPP.

Analysis of ALPL gene variant in a patient with infantile hypophosphatasia / 中华医学遗传学杂志

OBJECTIVE@#To explore the genetic basis for a girl featuring bone and tooth mineralization disorder, premature deciduous teeth, rickets and short stature.@*METHODS@#Genomic DNA was extracted and subjected to high-throughput whole exome sequencing. Suspected variants were confirmed by Sanger sequencing. Impact of potential variants was analyzed with bioinformatic software.@*RESULTS@#The child was found to carry compound heterozygous missense variants of the ALPL gene, including c.1130C>T (p.A377V), a known pathogenic mutation inherited from her father, and c.1300G>A (p.V434M) inherited from her mother, which was unreported previously and predicted to be likely pathogenic based on standards and guidelines from the American College of Medical Genetics and Genomics (PM2+PM5+PP3+PP4).@*CONCLUSION@#The compound heterozygous variants of c.1130C>T (p.Ala377Val) and c.1300G>A (p.Val434Met) of the ALPL gene probably underlay the disease in this child. Above finding has enriched the spectrum of ALPL gene variants.

A two-year follow-up of asfotase alfa replacement in a patient with hypophosphatasia: clinical, biochemical, and radiological evaluation

SUMMARY Hypophosphatasia (HPP) is a rare disease with a high mortality rate in its severe forms. It is caused by mutations within the gene encoding the tissue-nonspecific alkaline phosphatase (TNSALP), an enzyme responsible for bone mineralization. In 2015, the Food and Drug Administration approved the use of asfotase alfa, the first medication showing benefit in the treatment of HPP. We describe a case with a 2-year follow-up of the first Brazilian child treated with asfotase alfa. A 5-year-old boy, born to consanguineous parents, was diagnosed with HPP at the age of 20 months. During prenatal ultrasonography, polyhydramnios and shortening of long bones were detected. After birth, he presented delayed motor development, repeated respiratory infections, and bone deformities. At the age of 2 years and 8 months, he started walking and had already lost his primary teeth. He had reduced levels of alkaline phosphatase (ALP), elevated levels of pyridoxal 5'-phosphate (PLP), and a p.Ala33Val (c.98C>T) missense mutation in homozygosis in the TNSALP gene. His parents and sister also had reduced ALP levels, high PLP levels, and the same mutation in heterozygosis. His father and sister were healthy, and his mother was diagnosed with rickets in childhood, which resulted in short physical stature and lower limb deformities. The patient was started on asfotase alfa at the age of 2 years and 10 months. After 2 years of treatment, he improved his motor skills, had no further episodes of severe respiratory infection, and showed improved radiological findings of rickets, without any severe side effect.

Hipofosfatasemia crónica persistente de causa no determinada y su repercusión músculo-esquelética / Persistent hypophosphatasemia and its musculoskeletal repercussion

La fosfatasa alcalina baja o hipofosfatasemia, ya sea debida a causas genéticas (hipofosfatasia) o secundarias, presenta correlato clínico. Nuestro objetivo es estimar la prevalencia de hipofosfatasemia crónica persistente y describir sus hallazgos osteometabólicos. Se realizó una búsqueda electrónica de afiliados adultos al Hospital Italiano de Buenos Aires, entre 2013 y 2017, con al menos 2 determinaciones de fosfatasa alcalina igual a 30 UI/l o menor y ninguna mayor de 30 UI/l (rango de referencia 30-100 UI/l). Se excluyeron aquellos con causas secundarias diagnosticadas y se analizaron los correlatos clínico y bioquímico. Se detectó hipofosfatasemia crónica persistente en 78 de 105.925, 0,07% (0,06-0,09) de los afiliados. Solo uno fue excluido por tener causa secundaria. Eran 61,1% mujeres de 44 (34-56) años, fosfatasa alcalina 24 (20-27) UI/L, fosfatemia 4,1 (3,8-4,6) mg/dl. Se observaron osteoartritis, calcificaciones vasculares y fracturas, menos frecuentemente litiasis renal, calcificación del ligamento longitudinal común anterior, pérdida dental y convulsiones. El 63,6% tenían al menos una de las características clínico-radiológicas evaluadas, pero en solo 5,2% fue mencionado el diagnóstico de hipofosfatasemia en la historia clínica. La densitometría evidenció algún grado de afección (osteopenia u osteoporosis) en 76,2%. Se constataron 19 fracturas, con predominio en radio. La prevalencia de hipofosfatasemia fue similar a lo previamente reportado. El reconocimiento fue bajo; sin embargo, se observaron variadas manifestaciones músculo-esqueléticas, similares a las descriptas en la hipofosfatasia del adulto, por lo cual ­ante una hipofosfatasemia sin causa secundaria­ se sugiere considerar este diagnóstico. (AU)

Low alkaline phosphatase (ALP) or hypophosphatasemia either due to genetic (hypophosphatasia) or secondary causes, presents a clinical correlate. Our objectives are to estimate the prevalence of persistent hypophosphatasemia and to describe the clinical findings. We performed a search using the electronic medical records of the members of the Hospital Italiano de Buenos Aires health care system, between 2013 and 2017. Adult members with ≥ 2 ALP ≤ 30 IU/l, no ALP >30 IU/l (normal range 30-100 UI/l) and without diagnosed secondary causes were analyzed. Persistent hypophosphatasemia was detected in 78 of 105.925, 0.07% (0.06-0.09) of members. Only one was excluded due to a secondary cause, 61.1% were women, 44 (34-56) year-old, ALP 24 (20-27) IU/l and phosphatemia 4.1 (3.8-4.6) mg/dl. Osteoarthritis, vascular calcifications and fractures were detected, and nephrolithiasis, DISH (Diffuse idiopathic skeletal hyperostosis), tooth loss, and seizures were less frequently observed. At least one of the mentioned characteristics were present in 63.6 %, but only 5.2% had hypophosphatasemia registered in their clinical record. Densitometry showed osteopenia or osteoporosis in 76.2%. There were 19 fractures, most of them in radius. The prevalence of hypophosphatasemia was similar to what has been previously reported. Hypophosphatasemia finding in medical records was low, but far from being asymptomatic, clinical manifestations were observed. In the presence of hypophosphatasemia without a secondary cause, adult hypophosphatasia should be uspected. (AU)

A rare mutation in hypophosphatasia: a case report of adult form and review of the literature

SUMMARY Hypophosphatasia is a rare inborn error of metabolism characterized by low serum alkaline phosphatase activity due to loss-of-function mutations in the gene encoding the tissue-nonspecific isoenzyme of alkaline phosphatase (TNSALP). Extracellular accumulation of TNSALP substrates leads to dento-osseous and arthritic complications featuring tooth loss, rickets or osteomalacia, and calcific arthopathies. Mild hypophosphatasia usually has autosomal dominant inheritance, severe cases are either autosomal recessive or due to a dominant negative effect. Clinical manifestations of hypophosphatasia are extremely variable, ranging from life threatening to asymptomatic clinical presentations. The clinical presentation of the adult-onset hypophosphatasia is highly variable. Fractures, joint complications of chondrocalcinosis, calcifying polyarthritis and multiple pains may reveal minor forms of the disease in adults. It is important to recognize the disease to provide the best supportive treatment and to prevent the use of anti-resorption drugs in these patients. Bone-targeted enzyme-replacement therapy (asfotase alfa) was approved in 2015 to treat pediatric-onset hypophosphatasia. We present a case of a 41-year-old male diagnosed with adult form of hypophosphatasia with a rare ALPL mutation that has been previously described only once and review the literature on the adult form of the disease and its genetic mechanism.

Skeletal mineralization: mechanisms and diseases

Skeletal mineralization is initiated in matrix vesicles (MVs), the small extracellular vesicles derived from osteoblasts and chondrocytes. Calcium and inorganic phosphate (Pi) taken up by MVs form hydroxyapatite crystals, which propagate on collagen fibrils to mineralize the extracellular matrix. Insufficient calcium or phosphate impairs skeletal mineralization. Because active vitamin D is necessary for intestinal calcium absorption, vitamin D deficiency is a significant cause of rickets/osteomalacia. Chronic hypophosphatemia also results in rickets/osteomalacia. Excessive action of fibroblast growth factor 23 (FGF23), a key regulator of Pi metabolism, leads to renal Pi wasting and impairs vitamin D activation. X-linked hypophosphatemic rickets (XLH) is the most common form of hereditary FGF23-related hypophosphatemia, and enhanced FGF receptor (FGFR) signaling in osteocytes may be involved in the pathogenesis of this disease. Increased extracellular Pi triggers signal transduction via FGFR to regulate gene expression, implying a close relationship between Pi metabolism and FGFR. An anti-FGF23 antibody, burosumab, has recently been developed as a new treatment for XLH. In addition to various forms of rickets/osteomalacia, hypophosphatasia (HPP) is characterized by impaired skeletal mineralization. HPP is caused by inactivating mutations in tissue-nonspecific alkaline phosphatase, an enzyme rich in MVs. The recent development of enzyme replacement therapy using bone-targeting recombinant alkaline phosphatase has improved the prognosis, motor function, and quality of life in patients with HPP. This links impaired skeletal mineralization with various conditions, and unraveling its pathogenesis will lead to more precise diagnoses and effective treatments.

Niveles bajos de fosfatasa alcalina en niños, revisión retrospectiva / Low levels of alkaline phosphatase in children, retrospective review

Introducción: Los niveles elevados de fosfatasa alcalina (FAL) son utilizados en la evaluación de enfermedades hepatobiliares y óseas, pero los niveles disminuidos en general, no son tenidos en cuenta a pesar de ser indicadores de enfermedad como la Hipofosfatasia. Es importante contar con valores de referencia ajustados para edad y sexo. Objetivo: Determinar en los niños que consultan al endocrinólogo pediatra, la proporción de pacientes que presentan una FAL disminuida. Material y Métodos: Se realizó una revisión de corte transversal, retrospectiva, de todas las FAL que se determinaron a pacientes en consulta en la División de Endocrinología Infantil. Resultados: se obtuvieron 5.110 determinaciones de FAL, 938 (18%) presentaban una FAL menor a 100 U/L, los cuales correspondían a 634 pacientes. Los pacientes menores de 18 años fueron categorizados de acuerdo con los valores de referencia de D'Isa y col. y de Colantonio y col. La distribución etaria fue dispersa, con un rango de 2,94 años a 16,13 años, una mediana de 11,88 años; 93% pertenecía al sexo femenino y se describieron los datos clínicos relevantes de los pacientes. Si bien en sus historias clínicas se encontraba registrado, dicho valor no fue jerarquizado. Conclusión: La proporción de pacientes con niveles de FAL menores a 100 U/L es de un 18% que disminuye notablemente si se consideran algunos métodos de referencia propuestos. Es indispensable contar con valores de referencia de FAL ajustados a sexo y edad adecuados para alertar al médico de valores bajos y altos de FAL

Introduction: High levels of Alkaline Phosphatase (ALP) are used in the evaluation of hepatobiliary and bone diseases, but generally decreased levels are not considered despite being indicators of disease such as hypophosphatasia. It is important to have reference values adjusted for age and sex. Objective: to determine in the children who consult the pediatric endocrinologist, the proportion of patients who have a decreased ALP. Material and Methods: A cross-sectional, retrospective review was made of all the ALP´s that were determined to patients in consultation at the Division of Pediatric Endocrinology. Results: 5110 ALP determinations were obtained, 938 (18%) had an ALP less than 100 U/L, which corresponded to 634 patients. Patients younger than 18 years were categorized according to the reference values of D'Isa et al., and Colantonio et al. The age of distribution was scattered, with a range of 2.94 years to 16.13 years, a median of 11.88 years and 93% belonged to the female sex, and the relevant clinical data of the patients were described. Although it was registered in medical records, this value was not considered relevant. Conclusion: The proportion of patients with FAL levels lower than 100 U / L is 18%, which decreases considerably if some proposed reference methods are considered. It is essencial to have FAL reference values adjusted to sex and age to alert the physician of low and high FAL values

Caso clínico: hipofosfatasia de la niñez. Seguimiento clínico / Clinical case: childhood hypophosphatasia. Clinical follow-up

La hipofosfatasia (HP) es una enfermedad congénita, causada por mutaciones con pérdida de función en el gen ALPL que codifica la isoenzima no específica de tejido de la fosfatasa alcalina (TNSALP). Su expresión clínica es muy variable, desde casos de muerte intraútero por alteración grave de la mineralización ósea, hasta casos solo con caída prematura de la dentición. Se presenta el caso clínico de un varón al que se le diagnosticó odontohipofosfatasia a los 30 meses por pérdida temprana de piezas dentarias y niveles anormalmente bajos de fosfatasa alcalina, sin signos de raquitismo ni deformidades óseas. Durante su seguimiento, hasta los 13 años, presentó síntomas compatibles con HP infantil leve, como cansancio al caminar, incoordinación en la marcha y dolor en miembros inferiores que aumentaban con la actividad física. Ante la aparición de edema bimaleolar y poca respuesta al tratamiento con calcitonina y antiinflamatorios, se descartaron patologías infecciosas o reumáticas o ambas y se diagnosticó, por biopsia de tibia y peroné, periostitis sin detección de cristales de pirofosfato. Los controles radiológicos durante su evolución mostraron ensanchamiento metafisario en muñeca, falta de remodelado de metacarpianos, hojaldrado perióstico en tibia y peroné e hipomineralización en metáfisis tibiales, con "lenguas radiolúcidas" características de HP. Como conclusión, la hipofosfatasia debe considerarse como una entidad clínica para descartar en niños que presentan pérdida temprana de dientes. La presencia de este cuadro clínico es en general suficiente para realizar el diagnóstico de HP de la niñez. (AU)

Hypophosphatasia (HP) is a congenital disease, caused by mutations with loss of function in the gene ALPL that encodes the non-specific tissue isoenzyme of alkaline phosphatase (TNSALP). Its clinical expression displays considerable variability, from cases of intrauterine death due to severe alteration of bone mineralization, to cases with only early loss of teeth. We report the case of a male, diagnosed as odontohypophosphatasia at 30 months of age due to early loss of teeth and abnormally low levels of alkaline phosphatase, without signs of rickets or bone deformities. During follow-up, up to 13 years of age, he presented symptoms consistent with mild infantile HP such as tiredness when walking, lack of gait coordination, and pain in lower limbs, especially after physical activity. Due to the appearance of bimalleolar edema and poor response to treatment with calcitonin and anti-inflammatory drugs, infectious and / or rheumatic pathologies were ruled out. Periostitis without pyrophosphate crystal detection was diagnosed by tibial and fibular biopsy. Radiological controls during follow up showed metaphyseal wrist enlargement, lack of remodeling of metacarpals, periosteal flaking in the tibia and fibula and hypomineralization in the tibial metaphysis, with "radiolucent tongues"; characteristic of HP. In conclusion, hypophosphatasia should be considered as a clinical entity in children who present early loss of teeth. The presentation of this clinical case is generally sufficient to make the diagnosis of childhood HP. (AU)

Infantile hypophosphatasia caused by a novel compound heterozygous mutation: a case report and pedigree analysis / 中国当代儿科杂志

This article reported the clinical features of one child with infantile hypophosphatasia (HPP) and his pedigree information. The proband was a 5-month-old boy with multiple skeletal dysplasia (koilosternia, bending deformity of both radii, and knock-knee deformity of both knees), feeding difficulty, reduction in body weight, developmental delay, recurrent pneumonia and respiratory failure, and a significant reduction in blood alkaline phosphatase. Among his parents, sister, uncle, and aunt (other family members did not cooperate with us in the examination), his parents and aunt had a slight reduction in alkaline phosphatase and his aunt had scoliosis; there were no other clinical phenotypes or abnormal laboratory testing results. His ALPL gene mutation came from c.228delG mutation in his mother and c.407G>A compound heterozygous mutation in his father. His aunt carried c.228delG mutation. The c.407G>A mutation had been reported as the pathogenic mutation of HPP, and c.228delG mutation was a novel pathogenic mutation. Hypophosphatasia is caused by ALPL gene mutation, and ALPL gene detection is an effective diagnostic method. This study expands the mutation spectrum of ALPL gene and provides a theoretical basis for genetic diagnosis of this disease.

Prenatal diagnosis of hypophosphatasia congenita using ultrasonography

Congenital hypophosphatasia is a rare fatal skeletal dysplasia. Antenatal determinants of Epub ahead of print lethality include small thoracic circumference with pulmonary hypoplasia and severe micromelia. These features were present in the fetus of a 25-year-old female who came for an anomaly scan in her second trimester of pregnancy. Additional findings of generalized demineralization and osteochondral spurs led to the diagnosis of hypophosphatasia congenita. The pregnancy was terminated, and the findings were confirmed on autopsy. Common differential diagnoses with clues to diagnose the above mentioned condition have been discussed here. Early and accurate detection of this medical condition is important as no treatment has been established for this condition. Therefore, antenatal ultrasonography helps in diagnosing and decision making with respect to the current pregnancy and lays the foundation for the genetic counseling of the couple.

A Case of Calcium Pyrophosphate Dihydrate Deposition Disease Associated with Primary Hyperparathyroidism

Calcium pyrophosphate dihydrate (CPPD) deposition disease is a heterogeneous group of diseases with CPPD crystal deposition. Aging is the most common risk factor for CPPD deposition, followed by osteoarthritis and previous injury. Occasionally, CPPD depositions are associated with familial predisposition and metabolic diseases, including hemochromatosis, primary hyperparathyroidism, hypophosphatasia, and hypomagnesemia. CPPD deposition diseases associated with primary hyperparathyroidism in Koreans have rarely been reported. Thus, we report a case of a relatively young female patient with CPPD deposition disease associated with primary hyperparathyroidism, which was diagnosed through a polarized microscopic examination of the synovial fluid and a subtotal parathyroidectomy.

Tumor mesenquimatoso fosfatúrico de fosa nasal con compromiso intracraneano: reporte de un caso y revisión de la literatura / Nasal fossa phosphaturic mesenchymal tumor with intracraneal compromise: case report and review of the literature

El tumor mesenquimatoso fosfatúrico (TMF) es una enfermedad extremadamente rara. Según evidencia reciente es causado por la sobreexpresión del factor de crecimiento fibroblástico 23 (FGF23), el cual genera hipofosfemia y osteomalacia. A continuación presentamos el caso de un paciente de 42 años con un tumor mesenquimatoso fosfatúrico de fosa nasal izquierda con extenso compromiso intracraneano. Cabe destacar que hasta la fecha hay 142 casos reportados de TMF en la literatura de los cuales solo 11 se ubican en fosa nasaly cavidades sinusales, y sólo dos de ellos ubicados en fosa nasal¹. El paciente tuvo una exitosa resolución quirúrgica con la consecuente normalización de parámetros analíticos (incluido el FGF23), mejoría sintomática y ausenia de recidiva hasta la fecha.

The phosphaturic mesenchymal tumor (PMT) is an extremely rare disease. According to recent evidence is caused by overexpression of fibroblast growth factor 23 (FGF23) which generates hypophosphatemia and osteomalacia. We report the case of a 42 year old patient with a left nasal fossa phosphaturic mesenchymal tumor with intracranial involvement. Should be noted that to date there are 142 reported cases of PMT in the literature of which only 11 are located in nasal fossa and sinus cavities, two of them located in nasal fossa¹. The patient had a successful surgical resolution with consequent normalization of analytical parameters (including FGF23), absence of symptoms and no recurrence to date.

Rickets-like genetic diseases / 中国当代儿科杂志

This paper summarizes the clinical features, causative genes and treatment progress of patients with rickets-like genetic diseases, including X-linked hypophosphatemic rickets (XLH), hypophosphatasia, achondroplasia, vitamin D-dependent rickets, pycnodysostosis and ectodermal dysplasia, who visited the pediatric or child health clinic due to the symptoms of rickets, including bow legs, delayed closure of the anterior fontanelle, and sparse hair. Children with XLH usually go to hospital for bow legs and short stature, and biochemical evaluation reveals significantly low serum phosphorus so it is easily diagnosed. This disease is treated using phosphate mixture and 1,25(OH)2D3, which is different from the treatment of nutritional vitamin D deficiency rickets. Hypophosphatasia is characterized by a significant decrease in serum alkaline phosphatase, as well as normal serum calcium and phosphorus. The disease is caused by mutations in TNSALP gene. Patients with achondroplasia show short-limbed dwarfism and special face in addition to bow legs, but with normal serum calcium, phosphorus and alkaline phosphatase. Bone X-ray and FGFR3 gene test contribute to the diagnosis. Vitamin D-dependent rickets is an autosomal recessive disease, and active vitamin D supplement is effective in treatment of the disease. Patients with pycnodysostosis may be first seen at hospital because of large anterior fontanelle; in addition, they also show obtuse mandibular angle, dental abnormalities and dysplastic nails, which are caused by mutations in TSK gene. Children with ectodermal dysplasia may see a doctor for sparse hair, and they are easily misdiagnosed with nutritional vitamin D deficiency rickets. Ectodermal dysplasia is related to EDA, EDAR, EDARADD and WNT 10A genes.

Analysis of PHEX gene mutation in a hypophosphatasia pedigree / 中华医学遗传学杂志

<p><b>OBJECTIVE</b>To screen potential mutations of PHEX gene in a family featuring hypophosphatemic rickets in order to confirm the molecular diagnosis and pathogenetic mechanism.</p><p><b>METHODS</b>Genomic DNA was extracted from peripheral venous blood samples. DNA sequence of PHEX gene was derived from UCSC database, and primers for its coding region were designed with Primer premier 5.0. Potential mutations were detected with PCR amplification and DNA sequence analysis.</p><p><b>RESUTLS</b>A mutation was identified in intron 6 of the PHEX gene in the proband and his mother.</p><p><b>CONCLUSION</b>The c.732+1G>T mutation underlies the hypophosphatemic rickets in this family.</p>

Alterações periodontais associadas às doenças sistêmicas em crianças e adolescentes: [revisão] / Periodontal problems associated with systemic diseases in children and adolescents: [review]

OBJETIVO: O objetivo deste estuo foi revisar na literatura a inter-relação entre condições sistêmicas e a ocorrência de doenças periodontais em crianças e adolescentes, destacando-se as manifestações periodontais frequentemente encontradas. FONTES DE DADOS: Artigos indexados nas bases de dados Medline, Lilacs e Bibliografia Brasileira em Odontologia, nos últimos 20 anos, além de referências clássicas. As palavraschave utilizadas foram: "doença periodontal", "periodontite", "doenças sistêmicas", "criança" e "adolescente". SÍNTESE DOS DADOS: Doenças sistêmicas como hipofosfatasia, histiocitose X, síndrome de Down, síndrome de Papillon-Lefèvre, síndrome de Ehlers-Danlos, síndrome de Chédiak-Higashi, leucemias, Aids e as deficiências quantitativas e qualitativas dos neutrófilos estão associadas ao aparecimento de alterações periodontais graves em crianças e adolescentes. Os estudos demonstraram a ocorrência de alteração periodontal na forma de periodontite em crianças e adolescentes com doenças sistêmicas, podendo levar à perda precoce de dentes. CONCLUSÕES: A ocorrência de alterações periodontais é observada em crianças e adolescentes com alterações sistêmicas, que manifestam desde inflamação gengival até formas mais destrutivas, como periodontites e perda precoce dos dentes.

OBJETIVE: The aim of this study was to review the literature regarding the relationship between systemic conditions and the occurrence of periodontal diseases among children and adolescents, and to highlight the most common periodontal alterations. DATA SOURCE: Indexed articles published in the last 20 years on the following databases were searched: Medline, Lilacs, and the archives of the Brazilian Bibliography of Dentistry, in addition to classic references. Keywords included "periodontal disease", "periodontitis", "systemic diseases", "child", and "adolescent". DATA SYNTHESIS: Systemic diseases such as hypophosphatasis, histiocytosis X; Down, Papillon-Lefèvre, Ehlers-Danlos and Chédiak-Higashi syndromes, as well as leukemia, Aids, quantitative and qualitative neutrophilic deficiencies are associated with severe periodontal alterations among children and adolescents. Several studies demonstrated the occurrence of periodontitis, which can lead to early tooth loss among children and adolescents diagnosed with systemic diseases. CONCLUSIONS: The occurrence of periodontal alterations is observed in children and adolescents with systemic diseases. There are several manifestations, ranging from gingival inflammations to more destructive patterns, such as periodontitis and early teeth losses.