Development of a standard of care for patients with valosin-containing protein associated multisystem proteinopathy.

Valosin-containing protein (VCP) associated multisystem proteinopathy (MSP) is a rare inherited disorder that may result in multisystem involvement of varying phenotypes including inclusion body myopathy, Paget's disease of bone (PDB), frontotemporal dementia (FTD), parkinsonism, and amyotrophic lateral sclerosis (ALS), among others. An international multidisciplinary consortium of 40+ experts in neuromuscular disease, dementia, movement disorders, psychology, cardiology, pulmonology, physical therapy, occupational therapy, speech and language pathology, nutrition, genetics, integrative medicine, and endocrinology were convened by the patient advocacy organization, Cure VCP Disease, in December 2020 to develop a standard of care for this heterogeneous and under-diagnosed disease. To achieve this goal, working groups collaborated to generate expert consensus recommendations in 10 key areas: genetic diagnosis, myopathy, FTD, PDB, ALS, Charcot Marie Tooth disease (CMT), parkinsonism, cardiomyopathy, pulmonology, supportive therapies, nutrition and supplements, and mental health. In April 2021, facilitated discussion of each working group's conclusions with consensus building techniques enabled final agreement on the proposed standard of care for VCP patients. Timely referral to a specialty neuromuscular center is recommended to aid in efficient diagnosis of VCP MSP via single-gene testing in the case of a known familial VCP variant, or multi-gene panel sequencing in undifferentiated cases. Additionally, regular and ongoing multidisciplinary team follow up is essential for proactive screening and management of secondary complications. The goal of our consortium is to raise awareness of VCP MSP, expedite the time to accurate diagnosis, define gaps and inequities in patient care, initiate appropriate pharmacotherapies and supportive therapies for optimal management, and elevate the recommended best practices guidelines for multidisciplinary care internationally.

History of etidronate.

Etidronate is a non-nitrogen-containing bisphosphonate. Because it binds with calcium and inhibits crystal formation and dissolution, it was considered by Procter & Gamble as an additive to toothpaste (to prevent build-up of tartar) and detergent (to bind calcium and increase sudsing in "hard" water). The first clinical use (1968) was for fibrodysplasia ossificans progressiva. The first approved clinical use (1977) was for treatment of Paget's disease of bone. Other approved indications are hypercalcemia of malignancy and heterotopic ossification, with a host of off-label uses (including fibrous dysplasia, periodontal disease, multiple myeloma, neuropathic arthropathy, pulmonary microlithiasis, diabetic retinopathy, bone metastases, melorheostosis, urinary stone disease, periodontal disease, etc.). Unique among bisphosphonates, etidronate (oral therapy) results in hyperphosphatemia, increased tubular reabsorption of phosphorus and increased levels of 1,25-dihydroxyvitamin D. The dose that reduces bone resorption is close to the dose that impairs mineralization; prolonged high-dose use can result in osteomalacia and bone fractures. Intermittent cyclic etidronate for osteoporosis resulted in favorable changes in bone density and histomorphometry (no mineralization defect) as well as a decrease in vertebral fracture rates in postmenopausal women with osteoporosis. Later studies showed similar effects in men with osteoporosis and patients with glucocorticoid-induced osteoporosis. Although its use for osteoporosis has given way to newer bisphosphonates and other agents, because of its unique properties, it remains the bisphosphonate of choice for treatment of heterotopic ossification.

Preventive Role of Vitamin D Supplementation for Acute Phase Reaction after Bisphosphonate Infusion in Paget's Disease.

CONTEXT: Intravenous aminobisphosphonates (N-BPs) can induce an acute phase reaction (APR) in up to 40% to 70% of first infusions, causing discomfort and often requiring intervention with analgesics or antipyretics. OBJECTIVE: Our aim was to explore the risk factors of APR in a large sample of patients with Paget's disease of bone (PDB) and to assess the possible preventive effects of vitamin D administration. METHODS: An observational analysis was performed in 330 patients with PDB at the time of N-BP infusion. Then, an interventional study was performed in 66 patients with active, untreated PDB to evaluate if vitamin D administration (oral cholecalciferol 50 000 IU/weekly for 8 weeks before infusion) may prevent APR. RESULTS: In a retrospective study, APR occurred in 47.6% and 18.3% of naive or previously treated patients, respectively. Its prevalence progressively increased in relation to the severity of vitamin D deficiency, reaching 80.0% in patients with 25-hydroxyvitamin D (25OHD) levels below 10 ng/mL (relative risk (RR) = 3.7; 95% confidence interval (CI) 2.8-4.7, P < .0001), even in cases previously treated with N-BPs. Moreover, APR occurred more frequently in patients who experienced a previous APR (RR = 2.8; 95% CI 1.5-5.2; P < .001) or in carriers of SQSTM1 mutation (RR = 2.3; 95% CI 1.3-4.2; P = .005). In the interventional study, vitamin D supplementation prevented APR in most cases, equivalent to a RR of 0.31 (95% CI 0.14-0.67; P < .005) with respect to prevalence rates of the observational cohort. A similar trend was observed concerning the occurrence of hypocalcemia. CONCLUSIONS: The achievement of adequate 25OHD levels is recommended before N-BP infusion in order to minimize the risk of APR or hypocalcemia in PDB.

Distrofia ósea esclerosante mixta / Mixed-sclerosing-bone-dystrophy

El término "distrofia ósea esclerosante mixta" describe la combinación de las características radiológicas correspondientes a melorreostosis, osteopoiquilosis y osteopatía estriada, como entidades individuales, que ocurren en un mismo paciente. El objetivo de esta comunicación es presentar el caso clínico de una paciente con diagnóstico de distrofia ósea esclerosante mixta y, a partir de este caso, realizar una revisión sobre el tema. (AU)

The term "mixed-sclerosing-bone-dystrophy" describes the combination of the radiological characteristics corresponding to melorheostosis, osteopoikilosis and osteopathia striata, as individual conditions, ocurring in the same patient. The aim of this communication is to present the clinical case of a patient diagnosed with mixed-sclerosing-bone-dystrophy and, based on this case, to undertake a review of this condition. (AU)

Human Genetics of Sclerosing Bone Disorders.

PURPOSE OF REVIEW: The group of sclerosing bone disorders encompasses a variety of disorders all marked by increased bone mass. In this review, we give an overview of the genetic causes of this heterogeneous group of disorders and briefly touch upon the value of these findings for the development of novel therapeutic agents. RECENT FINDINGS: Advances in the next-generation sequencing technologies are accelerating the molecular dissection of the pathogenic mechanisms underlying skeletal dysplasias. Throughout the years, the genetic cause of these disorders has been extensively studied which resulted in the identification of a variety of disease-causing genes and pathways that are involved in bone formation by osteoblasts, bone resorption by osteoclasts, or both processes. Due to this rapidly increasing knowledge, the insights into the regulatory mechanisms of bone metabolism are continuously improving resulting in the identification of novel therapeutic targets for disorders with reduced bone mass and increased bone fragility.

A likely cranial osteodystrophy (Paget's disease of bone) in a Precolumbian, Mesoamerican stone sculpture.

This short note illustrates facial and head features found in a stone sculpture of the ancient, Precolumbian period in a temple of the Mayan city of Copan (Honduras). The authors believe that this observation may support paleoanthropological evidence of Paget's disease of bone, an osteodystrophy described in the Mesoamerican Indian populations before the first millennium A.D.

Inhibition of cancer cell mitosis by reducing the availability of phosphate.

The addition of phosphate groups is an essential requirement for the proper functioning of cyclin and cyclin dependent kinase which control various stages in the mitotic division of cancer cells. Thus limiting the availability of phosphate is likely to interfere with the metabolism of rapidly growing malignant cells. The human hormone glucagon and the anti metabolite mithramycin reduce serum phosphate by increasing phosphaturia and are both very effective in treating Paget's disease of bone, a precancerous condition. In this disorder large doses of glucagon given intravenously relieve bone pain and cause serum phosphate and alkaline phosphatase as well as urine hydroxyproline to fall, indicating a marked reduction in bone turnover. A constant iv infusion of glucagon was given to each of three patients all of whom had secondary malignant bone deposits. Two of the patients had primary prostate cancer and one had a squamous cell lung tumour. All three patients had relief of bone pain and a fall in serum alkaline phosphatase. Serum acid phosphatase also fell in the two patients with prostate cancer. It is proposed that the marked drop in serum phosphate due to glucagon causes intracellular phosphate to fall. This in turn disrupts the addition and removal of phosphate groups essential for the proper functioning of cyclin and cyclin dependent kinase. These two proteins control the transition from G1 to S (DNA synthesis phase) and G2 to M (mitotic phase) in the dividing cycle of malignant cells. Depriving a tumour of an essential ingredient used in phosphorylation reactions will disrupt its growth. It is also proposed that, by the same mechanism, glucagon induced hypophosphataemia renders malignant cells more sensitive to established chemotherapeutic agents and radiation waves. If this hypothesis proves to be correct, lowering intracellular phosphate may become an useful tool in cancer therapy. However extensive studies are necessary to determine whether mitosis in cancer cells can be advantageously disrupted by glucagon induced hypophosphataemia.

Eficácia, segurança e custo-efetividade do ácido zoledônico no tratamento da doença de Paget / Eficacia, seguridad y coste-efectividad del ácido zoledrónico para el tratamiento de la enfermedad de Paget / Efficacy, safety and cost-effectiveness of zoledronic acid for the treatment of Paget's disease

TECNOLOGIA: Ácido zoledrônico. INDICAÇÃO: Tratamento da doença de Paget - osteíte deformante. CARACTERIZAÇÃO DA TECNOLOGIA: O ácido zoledrônico pertence à classe de bisfosfonados contendo nitrogênio e atua especificamente nos ossos. É um inibidor da reabsorção óssea mediada por osteoclastos. PERGUNTA: O ácido zoledrônico é mais eficaz e seguro no tratamento da doença de Paget do que os medicamentos fornecidos pelo SUS ou demais alternativas terapêuticas? BUSCA E ANÁLISE DAS EVIDÊNCIAS CIENTÍFICAS: Foram pesquisadas as bases de dados eletrônicas Medline (via pubmed) e The Cochrane Library. Foram incluídos ensaios clínicos randomizados e controlados (ECR) que avaliassem a eficácia do ácido zoledrônico no tratamento da doença de Paget comparado aos medicamentos disponíveis no SUS: alendronato, risedronato, pamidronato, raloxifeno, calcitonina, calcitriol e carbonato de cálcio mais colecalciferol. Adicionalmente, foram pesquisados guias terapêuticos, avaliações de tecnologias de saúde e avaliações econômicas. RESUMO DOS RESULTADOS ENCONTRADOS: Foram incluídos seis ECR e três guias clínicos. Nenhum estudo de avaliação de tecnologia em saúde foi encontrado. Todos os seis ECR incluídos nesse PTC apresentaram resultados de desfechos favoráveis ao ácido zoledrônico, como remissão da doença, redução da dor e melhora na qualidade de vida dos pacientes. Esses ensaios foram classificados como sendo de qualidade moderada, devido a aspectos técnicos na condução do estudo e análises de dados. Dos ECR incluídos, dois compararam o ácido zoledrônico versus risedronato, um comparou ácido zoledrônico versus pamidronato e três compararam ácido zoledrônico versus placebo. Os desfechos laboratoriais principais relacionados à doença de Paget (redução dos níveis séricos de fosfatase alcalina e produtos do colágeno) se mostraram significantes a favor do ácido zoledrônico frente a todos os comparadores, na maioria dos ECR incluídos. Não foram avaliados desfechos finalísticos, como a incidência de fraturas. RECOMENDAÇÃO: Recomenda-se fracamente o uso do ácido zoledrônico como alternativa para o tratamento da doença de Paget. Esse medicamento apresentou resultados favoráveis para desfechos intermediários e nas análises de custo-efetividade. Além disso, o custo de tratamento com o medicamento no Brasil foi favorável em relação às alternativas do SUS. Por outro lado, os desfechos finalísticos da doença de Paget avaliados não permitem concluir sobre a eficácia do ácido zoledrônico na redução de fraturas, quedas ou outros resultados clínicos.(AU)

TECHNOLOGY: Zoledronic acid. INDICATION: Paget's disease treatment. CHARACTERIZATION OF TECHNOLOGY: Zoledronic acid belongs to the bisphosphonate class containing nitrogen and acts specifically on bone. It is an inhibitor of osteoclast-mediated bone resorption. QUESTION: Is zoledronic acid more effective and safe in the treatment of Paget's disease than medicines provided by SUS or other therapeutic alternatives? Search and analysis of scientific evidence: We searched electronic databases Medline (via Pubmed) and The Cochrane Library. Randomized controlled trials (RCTs) that evaluated the efficacy of zoledronic acid in the treatment of Paget's disease compared to available drugs in the SUS alendronate, risedronate, pamidronate, raloxifene, calcitonin, calcitriol and calcium carbonate associated with cholecalciferol were included. In addition, we found therapeutic guidelines regarding Paget's disease. In this study, we do not found any health technology assessment. SUMMARY OF RESULTS: Six RCTs and three clinical guidelines were included. All six RCTs included in this study presented outcomes favorable to zoledronic acid, as remission, pain reduction and increase quality of life. The trials were classified as being moderate quality due to technical aspects in conducting the study and data analysis. Of the included RCTs, two compared zoledronic acid versus risedronate, one compared zoledronic acid versus pamidronate and three compared zoledronic acid versus placebo. The main laboratory outcomes related to Paget's disease (reduced serum levels of alkaline phosphatase and collagen products) were significant in favor of zoledronic acid across all comparators in the majority of the RCTs included. Finalistic outcomes such as the incidence of fractures had not assessed. RECOMMENDATION: In weakly we recommend the use of zoledronic acid as an alternative for the treatment of Paget's disease. This medicine showed favorable results for intermediate outcomes and in the cost-effectiveness analyzes. Moreover, the cost of treatment with zoledronic acid in Brazil was favorable compared to SUS alternatives. On the other hand, the hard outcomes of Paget's disease assessed did not allow for conclusions about the efficacy of zoledronic acid in reducing fractures, falls or other clinical outcomes.(AU)

TECNOLOGÍA: El ácido zoledrónico. INDICACIÓN: Tratamiento de Paget- osteítis deformante enfermedad. CARACTERIZACIÓN DE LA TECNOLOGÍA: El ácido zoledrónico pertenece a la clase de los bisfosfonatos que contienen nitrógeno y actúa específicamente sobre el hueso. Es un inhibidor de la resorción ósea mediada por osteoclastos. Pregunta: Ácido zoledrónico es más eficaz y segura en el tratamiento de la enfermedad de los medicamentos proporcionados por alternativas terapéuticas SUS u otros de Paget? BÚSQUEDA Y ANÁLISIS DE LA EVIDENCIA CIENTÍFICA: Se realizaron búsquedas en bases de datos electrónicas MEDLINE (vía PubMed) y The Cochrane Library. Ensayos controlados aleatorios que se incluyeron (ECA) que evaluaron la eficacia del ácido zoledrónico en el tratamiento de la enfermedad de Paget en comparación con los fármacos disponibles en el SUS: alendronato, risedronato, pamidronato, raloxifeno, calcitonina, calcitriol y carbonato de calcio más colecalciferol. Además, se seleccionaron las guías terapéuticas. Sin la tecnología sanitaria estudio de evaluación encontró. RESUMEN DE LOS RESULTADOS: Seis ECA y tres guías clínicas fueron incluidos. Los seis ECA incluidos en esta PTC presentan los resultados de los resultados favorables de ácido zoledrónico, como remisión, reducción del dolor y la mejora en la calidad de vida de los pacientes. Estos ensayos fueron clasificados como de calidad moderada debido a aspectos técnicos en la realización del estudio y análisis de datos. De los ECA incluidos, dos compararon ácido zoledrónico frente a risedronato, un ácido zoledrónico en comparación contra el pamidronato y el zoledrónico comparado tres frente a ácido placebo. Los principales resultados de laboratorio relacionados con la enfermedad de Paget (reducción de los niveles séricos de fosfatasa alcalina y productos de colágeno) fueron clinicamente significativas a favor del ácido zoledrónico en todos los comparadores, en la mayoría de los ECA incluidos. RECOMENDACIÓN: Se recomienda débilmente utilizar el ácido zoledrónico como una alternativa para el tratamiento de la enfermedad de Paget. Este medicamento mostró resultados favorables para los resultados intermedios y en el análisis económico. Además, el costo del tratamiento con el medicamento en Brasil fue favorable en comparación con las alternativas de SUS. Por otra parte, los resultados duros de la enfermedad de Paget evaluados no permiten conclusiones acerca de la eficacia del ácido zoledrónico en la reducción de fracturas, caídas u otros resultados clínicos.(AU)

Two siblings with Paget's disease of bone.

Paget's disease of bone (PDB) is a chronic disorder characterised by focal areas of excessive osteoclastic bone resorption with a secondary increase in osteoblastic bone formation. First-degree relatives of patients with PDB are at seven times higher risk of developing this disorder, with a tendency towards earlier age at onset. We report two siblings who presented with features of polyostotic Paget's disease. They presented with features of non-inflammatory back pain. Biochemical evaluation was unremarkable except for elevated serum alkaline phosphatase. Subsequently, radiology and bone scans were diagnostic of polyostotic PDB. They were treated with bisphosphonates with which they improved.

Disorders of bone and bone mineral metabolism.

Metabolic bone disorders are very common in the general population and untreated, they can cause a variety of neurologic symptoms. These diseases include osteoporosis, vitamin D deficiency, Paget's disease, and alterations in calcium, phosphorus, and magnesium metabolism. Diagnosis is made through analysis of metabolic bone blood chemistries as well as radiologic studies such as dual energy X-ray absorptiometry (DXA) scans, bone scans, and X-rays. Treatment options have advanced significantly in the past decade for osteoporosis and Paget's disease and mainly include antiresorptive therapy. New recommendations for treatment of primary hyperparathyroidism are discussed as well as therapy for calcium, phosphorus, and mineral disorders.

Effects of RANK-ligand antibody (denosumab) treatment on bone turnover markers in a girl with juvenile Paget's disease.

CONTEXT: Juvenile Paget's disease (JPD) is an extremely rare, yet painful and debilitating bone disease with onset occurring during early childhood. JPD can be caused by loss of function of osteoprotegerin, resulting in subsequent stimulation of osteoclasts via the receptor activator of nuclear factor-κB (RANK) pathway. Increased bone turnover and lack of bone modeling lead to severe deformities, frequent fractures, short stature, and loss of hearing. SETTING: The treatment for JPD is challenging and has previously been based on administration of either calcitonin or bisphosphonates. However, with the development of denosumab, a receptor activator of nuclear factor-κB-ligand (RANKL) antibody, a treatment targeting the pathophysiology of JPD may be available. We report the effects of denosumab treatment on an 8-year-old girl with a severe form of JPD. PATIENT: Before starting the denosumab treatment regimen, the patient had been treated for 3.5 years with iv pamidronate. INTERVENTION AND OUTCOME: The administration of denosumab resulted in improved disease control compared with bisphosphonate, as assessed by monitoring markers of bone turnover. Alkaline phosphatase levels dropped within the normal range and remained at normal levels for 5 months after the final dose of denosumab. Additionally, bone pain was more efficiently controlled with denosumab. However, concomitant with the first injection, severe hypocalcemia developed, for which the patient was hospitalized and iv calcium supplementation was required for 13 days. CONCLUSIONS: Denosumab appears to be significantly effective for osteoclast inhibition for the treatment of JPD. However, in our patient, denosumab administration was associated with severe hypocalcemia, indicating that close monitoring of calcium levels is required during treatment.

[Paget's disease of bone: new therapeutic strategies]. / La malattia di Paget: a proposito di nuove strategie terapeutiche.

Paget's disease of bone is a chronic disorder of unknown etiology that can result in enlarged and misshapen bones. The excessive breakdown and formation of bone tissue cause affected bones to weaken, resulting in pain, misshapen bones, fractures, and arthritis in the joints. In most cases the diagnosis is achieved casually, as only 5% of patients develop burning pain at the level of affected bones. As regards therapy, the use of anti-reabsorbing drugs, such as bisphosphonates and calcitonin, appears reasonable. Given the disease pathogenesis, the administration of denosumab and tocilizumab may be a valuable alternative to inhibit RANK expression, and thus osteoclast formation, and interleukin-6 production.

Symptomatic intracranial hypertension and prolonged hypocalcemia following treatment of Paget's disease of the skull with zoledronic acid.

Skull involvement in Paget's disease of bone can lead to neurological symptoms, prompting treatment. Intravenous zoledronic acid (ZA) has emerged as an effective and safe treatment option for patients with Paget's, leading to sustained remission and improved quality of life. A previously untreated 61-year-old female presented with 2-year history of facial asymmetry with progressive hearing impairment. Serum calcium levels were normal with upper normal levels of PTH and low 25OHD levels. Serum alkaline phosphatase was markedly increased and bone scan showed extensive pagetic involvement of the skull. Head CT and MRI revealed hydrocephalus with cerebellar tonsillar herniation, platybasia and basilar invagination. In the absence of clinical signs or symptoms of intracranial hypertension, she was treated with intravenous ZA after 15-day supplementation with calcium and vitamin D. Twelve hours after the infusion, the patient became confused, agitated and disoriented and developed urinary incontinence; cortical sulci became effaced on CT indicating increased intracranial pressure. Over the following days, she developed frank hypocalcemia requiring intravenous calcium infusion and calcitriol. Neurological status returned to normal within 24 h of onset, except for urinary incontinence. Nine months later she remained incontinent and still required calcitriol to maintain normocalcemia. Zoledronic acid is a first-line option for the treatment of Paget's disease, yet there can be complications in particular clinical scenarios such as pagetic hydrocephalus, as seen in this case. Plentiful supplementation of calcium and vitamin D before bisphosphonate therapy is paramount in order to minimize the risk of prolonged post-treatment hypocalcemia.

Paget's disease of bone and calcium homeostasis: focus on bisphosphonate treatment.

Paget's disease of bone (PDB) is the second most common metabolic bone disease. Bisphosphonates (BPs) are currently the drugs of choice for PDB. PDB and osteomalacia are both common in the elderly. The concept of relative vitamin D deficiency in patients with PDB was suggested long ago, but it has not yet elucidated. Both diseases predispose to fractures, but their combined action to fragility has not been studied yet. The older BPs, mainly etidronate, further inhibit bone mineralization. Mineralization defects have also been described in patients with PDB treated with pamidronate. Moreover, hypocalcemia and secondary hyperparathyroidism after treatment with BPs have been described in PDB. Hypocalcemia seems to be more severe after treatment with the more potent, intravenous zoledronic acid, which is currently the treatment of choice for PDB. The counteracting hyperparathyroidism pathophysiologically intends to increase renal reabsorption of calcium and 1.25-dihydroxy vitamin D production and to stimulate osteoclasts in order to prevent long-term hypocalcemia. However, the effect of PTH on osteoclasts is, at least partly, restricted in patients taking BPs. Secondary hyperparathyroidism is a potentially detrimental condition, especially in patients already suffering from another bone disease. Serum calcium and vitamin D deficiency should be restored before BP treatment and calcium and vitamin D administration should be possibly continued for longer after achieving normocalcemia, which may shorten the duration of secondary hyperparathyroidism. QUICK SUMMARY: Mineralization defects and hypocalcemia with secondary hyperparathyroidism have been described in patients with Paget's disease of bone treated with bisphosphonates. Secondary hyperparathyroidism may be a potentially detrimental condition for patients with Paget's disease of bone.

Comparison of intravenous and intramuscular neridronate regimens for the treatment of Paget disease of bone.

Aminobisphosphonates actually represent the most common treatment for Paget disease of bone (PDB). In a previous study we demonstrated that either zoledronic acid (4 mg) or neridronate (200 mg) given as a single intravenous infusion showed a similar short-term efficacy in achieving biochemical remission in up to 90% of patient nonresponders to pamidronate. In this study we compared the long-term (36 months) effects of a same neridronate dose (200 mg) given as an intravenous (100-mg infusion for 2 consecutive days) or intramuscular (25-mg injection weekly for 2 months) regimen in 56 patients with active PDB. All patients were advised to receive calcium plus vitamin D supplementation throughout the study period. At 6 months, 92.6% and 96.5% of patients receiving intravenous and intramuscular neridronate, respectively, achieved a therapeutic response [defined as normalization of alkaline phosphatase (ALP) levels or a reduction of at least 75% in total ALP excess]. The response to treatment was significantly correlated with baseline ALP and 25-hydroxyvitamin D [25(OH)D] levels at 6 months. The decrease in ALP levels was highest in patients with higher baseline total or bone-specific ALP levels and with higher 25(OH)D levels at 6 months. Response rates were maintained at 12 months but decreased progressively at 24 and 36 months without significant differences between the two neridronate regimens. Both regimens were well tolerated. The only relevant side effect was an acute-phase response occurring in 14% of the patients. In conclusion, these results indicate that a 200-mg intramuscular neridronate course has a similar efficacy as an intravenous infusion of the same dose for the treatment of PDB and might be of particular value for patients intolerant to oral bisphosphonates and unwilling or unable to undergo intravenous infusions.

[Fibrous dysplasia and McCune-Albright syndrome: case-report and differential diagnose with Paget bone disease]. / Fibrodisplasia óssea e síndrome de McCune-Albright: descrição de um caso clínico e diagnóstico diferencial com doença óssea de Paget.

Fibrous dysplasia of bone or Jaffe Lischtenstein's disease is a genetic, non-inheritable disease of bone development, characterized by bone pain, deformities and fracture, mainly observed in yo ung adults. The frequency is equal between sexes. Mutations in the gene coding the Gsα, GNAS complex, results in osteoblastic differentiation defects, and bone resorption. The disease can have a monostotic or polyostotic form, or be associated with café-au-lait skin spots and precocious puberty (McCune-Al bright syndrome). The normal bone and bone marrow is replaced with abnormal benign intramedullary fibro-osseous tissue, and can involve any bone in the body. The vertebral involvement is rare. Radiological and pathological findings can be diagnostic. Biphosphonates and calcium, vitamin D and phosphorus supplements have been used in fibrous dysplasia treatment. Osteosarcoma is a rare, but serious malignant complication. We report the case of a 68 year old woman with a history of hypofisectomy, with a progressive low back pain, without systemic or neurological symptoms. The bone scan, the ra di o graphs and the computed tomography findings revealed polyostotic fibrous dysplasia, with vertebral and mandibular involvement. In this paper we compared fibrous dysplasia of bone with Paget bone disease.

Neridronic acid for the treatment of bone metabolic diseases.

Neridronic acid (6-amino-1-idroxyesilidene-1,1-bisphosphonate) is a nitrogen-containing bisphosphonate licensed in Italy for the treatment of osteogenesis imperfecta and Paget's disease of bone. The pharmacodynamic profile is similar to that of other nitrogen-containing bisphosphonates and is characterized by its high affinity for bone tissue particularly at sites undergoing a process of remodeling. In growing children affected by osteogenesis imperfect, neridronic acid rapidly increases bone mineral density as measured by dual X-ray absortiometry and this is associated with a significant decrease in fracture cumulative number. Similar results have been obtained also in newborns (< 12 month old) and in adult patients. In Paget's disease of bone, 200 mg intravenous neridronic acid is associated with a 65% rate of full remission and a biochemical response (decrease of > 75% of bone turnover markers) in 95% of the patients. Neridronic acid treatment has been reported to be effective also in other skeletal diseases such as osteoporosis, algodystrophy, hypercalcemia of malignancy and bone metastasis. Neridronic acid has been developed only for parenteral use, and it is the only one used as intramuscular injection. This avoids all the limitations of oral bisphosphonates and may be offered for a home treatment with simple nursing assistance.

A rare case of Paget's disease of the bone in the Philippines.

A 40-year-old Filipina presented with a 2-year history of progressive bilateral inguinal and hip pain with limited range of motion. She had a bad fall which led to widespread body pains for 6 months partially relieved on multiple analgesic and anti-inflammatory agents. There was progressive weight loss and anemia. Focused musculoskeletal examination revealed moderate degree of generalized muscle atrophy, pain-limited range of motion of bilateral hip and shoulder joints, with equivocal muscle strength of both proximal and distal muscle groups of all extremities. Metastatic bone disease was ruled out when skeletal survey disclosed mixture of osteolytic and osteoblastic lesions, predominantly osteoblastic, on multiple sites. Bone turnover markers were elevated. Bone biopsy revealed histopathologic results compatible with Paget's disease of the bone. Management included oral calcium and vitamin D supplement followed by parenteral zoledronic acid, and a rehabilitation program. Four months after bisphosphonate therapy, the patient reported significant relief of symptoms with complete resolution of the previously noted generalized body pains, although she ambulates with use of an assistive device. Due to the rarity of the condition among Filipinos, this case was a diagnostic dilemma in itself, as it is most likely the first published case in the Philippine literature.

Imaging of metabolic bone diseases.

Bone scintigraphy and X-ray are complementary in the assessment of Paget's disease. Whereas bone scintigraphy allows visualization of the whole skeleton and 'hot spots', X-ray enables visualization of more detailed images of the pagetic bone lesion. X-ray may be invaluable in the diagnosis of osteomalacia, especially in children. As osteomalacia is characterized by impaired bone mineralization, the use of bone density measures may lead to misinterpretation of the condition as osteoporosis. Dual-energy X-ray absorptiometry at the femoral neck is the 'gold standard' for the assessment of osteoporosis. However, all devices are useful to predict the risk of fracture. In the future, high-resolution computer tomography and magnetic resonance imaging may become valuable clinical tools, capturing the architectural aspect of bone strength and improving fracture prediction models.