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Background: Hereditary Fibrosing Poikiloderma (HFP) with tendon contractures, myopathy and pulmonary fibrosis (POIKTMP [MIM 615704]) is a very recently described entity of syndromic inherited poikiloderma. Previously by using whole exome sequencing in five families, we identified the causative gene, FAM111B (NM_198947.3), the function of which is still unknown. Our objective in this study was to better define the specific features of POIKTMP through a larger series of patients., Methods: Clinical and molecular data of two families and eight independent sporadic cases, including six new cases, were collected., Results: Key features consist of: (i) early-onset poikiloderma, hypotrichosis and hypohidrosis; (ii) multiple contractures, in particular triceps surae muscle contractures; (iii) diffuse progressive muscular weakness; (iv) pulmonary fibrosis in adulthood and (v) other features including exocrine pancreatic insufficiency, liver impairment and growth retardation. Muscle magnetic resonance imaging was informative and showed muscle atrophy and fatty infiltration. Histological examination of skeletal muscle revealed extensive fibroadipose tissue infiltration. Microscopy of the skin showed a scleroderma-like aspect with fibrosis and alterations of the elastic network. FAM111B gene analysis identified five different missense variants (two recurrent mutations were found respectively in three and four independent families). All the mutations were predicted to localize in the trypsin-like cysteine/serine peptidase domain of the protein. We suggest gain-of-function or dominant-negative mutations resulting in FAM111B enzymatic activity changes., Conclusions: HFP with tendon contractures, myopathy and pulmonary fibrosis, is a multisystemic disorder due to autosomal dominant FAM111B mutations. Future functional studies will help in understanding the specific pathological process of this fibrosing disorder.

Congenital poikiloderma is characterized by a combination of mottled pigmentation, telangiectasia, and epidermal atrophy in the first few months of life. We have previously described a South African European-descent family affected by a rare autosomal-dominant form of hereditary fibrosing poikiloderma accompanied by tendon contracture, myopathy, and pulmonary fibrosis. Here, we report the identification of causative mutations in FAM111B by whole-exome sequencing. In total, three FAM111B missense mutations were identified in five kindreds of different ethnic backgrounds. The mutation segregated with the disease in one large pedigree, and mutations were de novo in two other pedigrees. All three mutations were absent from public databases and were not observed on Sanger sequencing of 388 ethnically matched control subjects. The three single-nucleotide mutations code for amino acid changes that are clustered within a putative trypsin-like cysteine/serine peptidase domain of FAM111B. These findings provide evidence of the involvement of FAM111B in congenital poikiloderma and multisystem fibrosis., (Copyright © 2013 The American Society of Human Genetics. Published by Elsevier Inc. All rights reserved.)

Neutral lipid storage disease comprises a heterogeneous group of autosomal recessive disorders characterized by systemic accumulation of triglycerides in cytoplasmic droplets. Here we report a neutral lipid storage disease subgroup characterized by mild myopathy, absence of ichthyosis and mutations in both alleles of adipose triglyceride lipase (PNPLA2, also known as ATGL). Three of these mutations are predicted to lead to a truncated ATGL protein with an intact patatin domain containing the active site, but with defects in the hydrophobic domain. The block in triglyceride degradation was mimicked by short interfering RNA directed against ATGL. NLSDM is distinct from Chanarin-Dorfman syndrome, which is characterized by neutral lipid storage disease with ichthyosis, mild myopathy and hepatomegaly due to mutations in ABHD5 (also known as CGI-58).

Unlabelled: MACROPHAGIC MYOFASCIITIS: A most unusual inflammatory myopathy, first described by Germmad had been reported with increasing frequency since 1993 in the leading French myopathology centers. We present our experience with this new disease: macrophagic myofasciitis., Clinical Features: By November 1999, 70 cases of macrophagic myofasciitis had been recorded since our first description. The first 22 patients (sex ratio M/F = 1:3) referred with the presumptive diagnosis of polymyositis (n = 11), polymyalgia rheumatica (n = 5), mitochondrial cytopathy (n = 4), and congenital myopathy or muscle dystrophy (n = 1 each). Symptoms included myalgia (91%), anthralgia (68%), marked asthenia (55%), muscle weakness (45%), and fever (32%)., Laboratory Findings: Abnormal laboratory findings included elevated CK levels (50%), markedly increased erythrocyte sedimentation rate (37%), and myopathic EMG (35%). Muscle biopsy showed a unique myopathological pattern characterized by: i) centripetal infiltration of epimysium, perimysium and perifascicular endomysium by sheets of large cells of the monocyte/macrophage lineage (CD68+, CD1a-, S100-, with a PAS-positive content; ii) absence of necrosis, of both epithelioid and giant cells, and of mitotic figures; iii) presence of occasional CD8+ T-cells; iv) inconspicuous muscle fiber damage. The picture was easily distinguishable from sarcoid myopathy and fasciitis-panniculitis syndromes. The infectious diseases know to be associated with reactive histiocytes, including Whippleís disease, Mycobacterium avium intracellulare infection and malakoplakia, could not be documented. Patients improved under corticosteroid therapy and/or immunomodulatory therapeutic, Conclusion: A new inflammatory muscle disorder, characterized by a distinctive pathological pattern of macrophagic myofasciitis is emerging in France.

A new variant of multisystemic lipid storage myopathy (type 3) has been identified. Human cultured fibroblasts present a major triacylglycerol storage whereas other neutral lipids and phospholipids are in the normal range. When feeding the cells in the presence of radiolabelled oleic acid we observed an accumulation of radiolabelled triacylglycerols demonstrating the endogenous biosynthesis of the stored triacylglycerols. After a 72-hr chase period, no degradation of radiolabelled triacylglycerols was observed. Histochemical examination of multisystemic lipid storage myopathy skin fibroblasts showed a massive accumulation of neutral lipids (stained by the fluorescent probe Nile Red) in cells grown in medium supplemented with 10% fetal calf serum. These cytoplasmic vacuoles were not obviously membrane-surrounded as shown by electron microscopy.