A Case of Paget’s Disease of Bone Associated with Hypomyopathic Dermatomyositis

Dermatomyositis is associated with malignancies and is known to have systemic involvement. However, associations with bone diseases have not been well described in the current literature. This article describes the second reported case of the co-existence of dermatomyositis and Paget’s Disease of Bone (PDB), but is the first report to describe such co-existence in a specific subtype of dermatomyositis – hypomyopathic dermatomyositis. Our patient was a 51-year-old woman who presented with prolonged fever, myalgia, morning stiffness, and rashes pathognomonic of dermatomyositis. There was no muscle weakness clinically, although muscle enzymes were raised and electromyogram revealed myopathic changes. Further imaging showed the incidental finding of a T11 vertebral bone lesion, of which biopsy confirmed the diagnosis of PDB. Our report illustrates the diagnostic approach to bone lesions in patients with dermatomyositis, and takes a closer look at the pathophysiology and management implications of the co-occurrence of these two rare diseases.

Misdiagnosis of Paget’s Disease of Bone in a Congenital Generalized Lipodystrophy Patient: Case Report

Paget’s disease of bone (PDB) is a common skeleton disorder in which the diagnosis is suggested by radiological analyses. Congenital generalized lipodystrophy (CGL) is a rare, but a radiologic differential diagnosis of Paget’s disease. Patients present total or almost total lack of subcutaneous adipose tissue, leptin deficiency, and precocious ectopic lipid accumulation, which lead to intense insulin resistance, poorly controlled diabetes mellitus, and hypertriglyceridemia. CGL subtypes 1 and 2 present sclerosis and osteolytic lesions that can resemble “pagetic” lesions. The clinical correlation is, therefore, essential. We report a CGL patient with bone lesions in which the radiographic findings led to a misdiagnosis of PDB. This case report brings awareness to CGL, a life-threating condition. Its early recognition is essential to avoid clinical complications and premature death. Therefore, it is important to consider CGL as PDB’s differential diagnosis, especially in countries with high prevalence of this rare disease, such as Brazil.

Genetic Determinants of Paget’s Disease of Bone

Purpose of Review To provide an overview of the role of genes and loci that predispose to Paget’s disease of bone and related disorders. Recent Findings Studies over the past ten years have seen major advances in knowledge on the role of genetic factors in Paget’s disease of bone (PDB). Genome wide association studies have identified six loci that predispose to the disease whereas family based studies have identified a further eight genes that cause PDB. This brings the total number of genes and loci implicated in PDB to fourteen. Emerging evidence has shown that a number of these genes also predispose to multisystem proteinopathy syndromes where PDB is accompanied by neurodegeneration and myopathy due to the accumulation of abnormal protein aggregates, emphasising the importance of defects in autophagy in the pathogenesis of PDB. Summary Genetic factors play a key role in the pathogenesis of PDB and the studies in this area have identified several genes previously not suspected to play a role in bone metabolism. Genetic testing coupled to targeted therapeutic intervention is being explored as a way of halting disease progression and improving outcome before irreversible skeletal damage has occurred.

Paget’s Disease of Bone Affecting Site With Orthopedic Hardware

Introduction: Paget’s disease of bone is a focal disorder of accelerated bone remodeling which leads to bone hypertrophy, cortical expansion and abnormal bone architecture. Either a single bone (monostotic) or multiple bones (polyostotic) can be affected. Although it has been suggested to be caused by a chronic slow viral infection of the bone, a cause and effect relationship has not been clearly established. Therefore, the etiology of Paget’s disease remains an uncertain and controversial topic of discussion. Case Description: A 62-year-old African American male with a past medical history of a left tibial fracture presented with worsening left leg pain for the past 6 months. He denied any recent traumatic events, falls or strenuous physical activity. Since the pain started, his ambulation had been significantly affected requiring the use of a cane for gait stability. His left tibial fracture occurred over 20 years ago after landing on another person’s foot while playing basketball. It was surgically treated with intramedullary nailing and metal rod insertion into the canal of the tibia. Since then, he remained an active person with no physical limitations or ailments until the recent developments that brought him to clinic. A left leg CT-Scan ordered for evaluation of the tibial hardware revealed cortical thickening, marrow expansion and coarse trabeculae throughout the majority of the tibia consistent with Paget’s disease. The hardware was intact with no peri-hardware lucency to suggest loosening or infection. His laboratory workup showed a normal alkaline phosphatase level (94 U/L; normal range 40 - 115 U/L) and low 25-OH Vitamin D level of 14. A Radionuclide Bone Scan done for evaluation of location and extent of bone disease resulted in diffusely abnormal uptake present in the left tibia with no other locations of suspicious uptake. After his 25-OH Vitamin D levels were replenished, a dose of Zoledronic acid IV infusion was given with significant improvement of pain several months after. Discussion: Paget’s disease of bone is the second most common bone disease after osteoporosis. Affected skeletal sites develop a disorganized mosaic of woven and lamellar bone more susceptible to deformities and fractures than normal bone. It is often asymptomatic, but classical features include bone pain experienced either at rest or with motion, cutaneous erythema and warmth. The goal of medical therapy is to relieve symptoms and to prevent future complications with high potency bisphosphonates. Although it is well known that Paget’s disease increase the risk of fractures, this case brings up an interesting take about the possibility of fractures managed with hardware placement increasing the risk of Paget’s disease in the involved site.