D.P.3.04. Inclusion body myopathy with Paget’s disease and frontotemporal dementia (IBMPFD): Extending the clinical features in a large pedigree

2008 ◽  
Vol 18 (9-10) ◽  
pp. 766
Author(s):  
R. Barresi ◽  
T.D. Miller ◽  
A.P. Jackson ◽  
R. Charlton ◽  
J. Stone ◽  
...  
2010 ◽  
Vol 17 (12) ◽  
pp. 1626
Author(s):  
Kishore Kumar ◽  
Christina Liang ◽  
Merrilee Needham ◽  
David Burke ◽  
Carolyn Sue ◽  
...  

2009 ◽  
Vol 187 (6) ◽  
pp. 875-888 ◽  
Author(s):  
Jeong-Sun Ju ◽  
Rodrigo A. Fuentealba ◽  
Sara E. Miller ◽  
Erin Jackson ◽  
David Piwnica-Worms ◽  
...  

Mutations in valosin-containing protein (VCP) cause inclusion body myopathy (IBM), Paget's disease of the bone, and frontotemporal dementia (IBMPFD). Patient muscle has degenerating fibers, rimmed vacuoles (RVs), and sarcoplasmic inclusions containing ubiquitin and TDP-43 (TARDNA-binding protein 43). In this study, we find that IBMPFD muscle also accumulates autophagosome-associated proteins, Map1-LC3 (LC3), and p62/sequestosome, which localize to RVs. To test whether VCP participates in autophagy, we silenced VCP or expressed adenosine triphosphatase–inactive VCP. Under basal conditions, loss of VCP activity results in autophagosome accumulation. After autophagic induction, these autophagosomes fail to mature into autolysosomes and degrade LC3. Similarly, IBMPFD mutant VCP expression in cells and animals leads to the accumulation of nondegradative autophagosomes that coalesce at RVs and fail to degrade aggregated proteins. Interestingly, TDP-43 accumulates in the cytosol upon autophagic inhibition, similar to that seen after IBMPFD mutant expression. These data implicate VCP in autophagy and suggest that impaired autophagy explains the pathology seen in IBMPFD muscle, including TDP-43 accumulation.


2020 ◽  
Vol 4 (Supplement_1) ◽  
Author(s):  
Clare Miller ◽  
Siobhan E Mcquaid

Abstract Background: Inclusion body myopathy associated with Paget disease of bone (PDB) and/or frontotemporal dementia (IBMPFD) is a rare, autosomal dominant condition, characterized by adult-onset muscle weakness, early-onset PDB, and premature frontotemporal dementia. Paget’s disease is a chronic disorder of bone resulting in increased bone resorption, followed by a disorganized and excessive formation of bone. Clinical Case: A 43 year old gentleman was referred to neurology services with foot drop, limb weakness and cognitive impairment. Following a prolonged period of diagnostic evaluation a mutation in valosin-containing protein (VCP) gene was uncovered IBMPFD has a variable phenotype which may include PDB. This gentleman denied bony pain and had an alkaline phosphatase within reference range. Plain film radiographs at multiple sights demonstrated no signs of PDB. An MRI whole body was performed which reported coarse trabecular markings in L2 vertebral body and multilevel degenerative changes with bridging osteophytes in the lumbar spine consistent with PDB. At initial review in endocrine clinic, he denied fractures or bone pain. He had no signs of increased cardiac output or cranial nerve deficits. A radionuclide bone scan identified intense radiopharmaceutical accumulation in L2 vertebral body consistent with MRI findings and also curvilinear increased activity in the left occipital bone and low-grade activity in the left hip, thus confirming polyostotic Paget’s disease. He received a 5mg IV infusion of zolendronate, side effects of which included myalgia, pyrexia and lethargy. Six months following the zoledronate infusion a repeat bone scan demonstrated that the extent of uptake at affected sites had decreased significantly. He subsequently fractured his left femur following a mechanical fall. PDB can affect up to 50% of patients with IBMFTD. PDB can lead to complications such as bone pain, localized pain and deformity of the long bones, pathologic fractures and deafness. This case highlights the association of Paget’s disease with IBMFTD and as it can be asymptomatic, as in our case, radiological imaging is required for diagnosis. It also reminds us that Paget’s disease can be due to genetic causes. Understanding the role of VCP in the cell cycle may help in further understanding bone physiology.


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