A form of muscular dystrophy associated with pathogenic variants in JAG2.

JAG2 encodes the Notch ligand Jagged2. The conserved Notch signaling pathway contributes to the development and homeostasis of multiple tissues, including skeletal muscle. We studied an international cohort of 23 individuals with genetically unsolved muscular dystrophy from 13 unrelated families. Whole-exome sequencing identified rare homozygous or compound heterozygous JAG2 variants in all 13 families. The identified bi-allelic variants include 10 missense variants that disrupt highly conserved amino acids, a nonsense variant, two frameshift variants, an in-frame deletion, and a microdeletion encompassing JAG2. Onset of muscle weakness occurred from infancy to young adulthood. Serum creatine kinase (CK) levels were normal or mildly elevated. Muscle histology was primarily dystrophic. MRI of the lower extremities revealed a distinct, slightly asymmetric pattern of muscle involvement with cores of preserved and affected muscles in quadriceps and tibialis anterior, in some cases resembling patterns seen in POGLUT1-associated muscular dystrophy. Transcriptome analysis of muscle tissue from two participants suggested misregulation of genes involved in myogenesis, including PAX7. In complementary studies, Jag2 downregulation in murine myoblasts led to downregulation of multiple components of the Notch pathway, including Megf10. Investigations in Drosophila suggested an interaction between Serrate and Drpr, the fly orthologs of JAG1/JAG2 and MEGF10, respectively. In silico analysis predicted that many Jagged2 missense variants are associated with structural changes and protein misfolding. In summary, we describe a muscular dystrophy associated with pathogenic variants in JAG2 and evidence suggests a disease mechanism related to Notch pathway dysfunction.

The TREAT-NMD DMD Global Database: analysis of more than 7,000 Duchenne muscular dystrophy mutations.

Analyzing the type and frequency of patient-specific mutations that give rise to Duchenne muscular dystrophy (DMD) is an invaluable tool for diagnostics, basic scientific research, trial planning, and improved clinical care. Locus-specific databases allow for the collection, organization, storage, and analysis of genetic variants of disease. Here, we describe the development and analysis of the TREAT-NMD DMD Global database (http://umd.be/TREAT_DMD/). We analyzed genetic data for 7,149 DMD mutations held within the database. A total of 5,682 large mutations were observed (80% of total mutations), of which 4,894 (86%) were deletions (1 exon or larger) and 784 (14%) were duplications (1 exon or larger). There were 1,445 small mutations (smaller than 1 exon, 20% of all mutations), of which 358 (25%) were small deletions and 132 (9%) small insertions and 199 (14%) affected the splice sites. Point mutations totalled 756 (52% of small mutations) with 726 (50%) nonsense mutations and 30 (2%) missense mutations. Finally, 22 (0.3%) mid-intronic mutations were observed. In addition, mutations were identified within the database that would potentially benefit from novel genetic therapies for DMD including stop codon read-through therapies (10% of total mutations) and exon skipping therapy (80% of deletions and 55% of total mutations).

Splicing Switching of Alternative Last Exons Due to a Deletion Including Canonical Polyadenylation Site in COL6A2 Gene Causes Recessive UCMD.

Objectives: Collagen VI-related myopathy spans a clinical continuum from severe Ullrich congenital muscular dystrophy to milder Bethlem myopathy, caused by genetic variants in COL6A1, COL6A2, and COL6A3 genes. Our objective was to report a newly identified patient with the pathogenic variants restricted to a polyadenylation signal in the 3'-untranslated region, which have not been reported in hereditary muscle disease. Methods: We performed clinicopathologic diagnosis and analysis using whole-genome and RNA sequencing. Results: We report Ullrich congenital muscular dystrophy caused by a homozygous deletion, c.*198_*466del, which includes a polyadenylation signal in the canonical last exon of the COL6A2 gene. The parents were consanguineously married and had the heterozygous variant, but they were completely asymptomatic. In the patient's muscles, collagen VI was deficient in the sarcolemma, but present in the interstitium, showing the pattern of sarcolemma-specific collagen VI deficiency rather than a pattern of complete deficiency despite the lack of a polyadenylation signal. The RNA sequencing of the patient's muscle showed that alternative last exons were raised in COL6A2 transcript. Discussion: Our case provides a valuable example of the mechanism of alternative splicing switches for polyadenylation selection.

Estimating Societal Cost of Illness and Patients' Quality of Life of Duchenne Muscular Dystrophy in Egypt.

OBJECTIVES: Duchenne muscular dystrophy (DMD) is a rare neuromuscular disease that causes substantial economic burden. This study aims to measure the DMD cost from societal perspective and the quality of life (QOL) of the Egyptian patients. METHODS: We conducted interviews with caregivers of patients with DMD. The questionnaire included demographics, healthcare resource use, and nonmedical and indirect costs. Total disease burden was estimated with a bottom-up approach. QOL was measured with a disease-specific tool. Costs and utilities were stratified by the disease stage. RESULTS: Caregivers of 97 patients with DMD were interviewed. The mean annual per-patient cost of $17 485 (SD ± 9240) was estimated resulting in a total burden of $138 217 043 in Egypt. Nonmedical costs made up the largest category representing 54% followed by medical then indirect costs. Informal care made the greatest contribution of nonmedical costs whereas physiotherapy was the largest medical subcategory. Nonmedical costs were highest in stage 3 and lowest at early stages whereas medical costs were almost steady among all stages with differences in individual subcategories. Of all medical costs, 95% were out of pocket. The mean utility score was 0.43 (± 0.31), which decreases with disease progression. CONCLUSION: Our study quantified the huge economic burden of DMD on the society and how it differs in different stages. Almost the whole burden is paid by households resulting in catastrophic expenditures, which leads to reduced compliance and quality of care. QOL is also severely compromised. Our findings can inform future healthcare policies and economic evaluation of new DMD therapies.

Early Cost-Utility Analysis of Ataluren and Eteplirsen in the Treatment of Duchenne Muscular Dystrophy in Egypt.

OBJECTIVES: Ataluren and eteplirsen are orphan drugs that delay progression of Duchenne muscular dystrophy in mutation-specific subgroups. They have yet to be approved in Egypt but are expected to reach the market soon. This study describes 2 cost-utility models comparing the drugs with the standard of care. METHODS: We used a partition-survival model with 5 states based on the ambulatory status to model a cohort of ambulatory patients at the age of 5 years. Baseline curves were obtained from a published model; then the ambulation loss curve was updated using the Kaplan-Meier curve of the standard of care from a study by McDonald et al. Other curves were updated by calibration to this curve. Costs and utilities were from a local study. Deterministic and probabilistic sensitivity analyses were conducted. Prices were estimated based on other orphan drugs' prices. RESULTS: In the base case, ataluren 1000 mg and eteplirsen 50 mg/mL resulted in an incremental cost-effectiveness ratio of EGP 51 745 605 and EGP 69 652 533/quality-adjusted life-year, respectively, at their hypothetical prices of EGP 308 600 for ataluren 30-sachet pack and EGP 62 800 for eteplirsen 10 mL vial. The incremental cost-effectiveness ratio was sensitive to health state utilities but not to state costs. At EGP 911 719/quality-adjusted life-year threshold, the value-based prices were EGP 4680 for ataluren 1000 mg and EGP 733 for eteplirsen 10 mL vial. CONCLUSIONS: Based on these models, there is a huge gap between the prices of orphan drugs and their value-based prices, which highlights the need for major policy reforms in the assessment and pricing of orphan drugs.

Virulent Escherichia coli strains among Egyptian patients with acute diarrhoea versus urinary tract infection, and their antibiotic susceptibility.

BACKGROUND AND STUDY AIMS: Diarrhoea and urinary tract infection (UTI) are common clinical problems. Meanwhile, Escherichia coli (E. coli), is the commonest bacterial pathogen reported in both of them. This study aimed to evaluate the pathogenic E. coli (PEC) in stool of acute diarrhoea and urine of UTI regarding their virulence genes and their influence on the susceptibility to routinely prescribed antibiotics. PATIENTS AND METHODS: Twenty two stool and another 22 urine samples of patients with acute diarrhoea and UTI respectively were collected from patients admitted at Kasr Al-Ainy Hospital, Faculty of Medicine, Cairo University, Egypt. E. coli isolation, identification of their phyla; chuA, yjaA, and TspE4.C2, and further identification of 10 virulent genes; fimH, papC, papG//, papG///, papEF, afa, sfa, CNF1, iroN & hlyA was performed. Antibiotic susceptibility was studied against quinolones, gentamicin (GM), and trimethoprim-sulphamethoxazole (TMP-SMX). RESULTS: The studied virulence genes were comparably detected in both pathogenic samples. In diarrheogenic E. coli (DEC); phylum A was significantly related to both ciprofloxacin (CIP) and TMP-SMX resistance, and both of the virulence genes fimH and iroN were significantly related to all the studied antibiotics resistance, while afa was significantly related to nalidixic acid (NA) resistance. In uropathogenic E. coli (UEC); phylum D was significantly related to CIP and levofloxacin resistance, and both of the virulence genes fimH and iroN were significantly related to most of the studied antibiotics resistance. CONCLUSION: The isolated PEC was evidently and broadly resistant to the studied antibiotics, with limited influence of their phyla and virulence genes (fimH and iroN).

Correction to: Eight years after an international workshop on myotonic dystrophy patient registries: case study of a global collaboration for a rare disease.

The original version of this article [1] unfortunately included an error to an author's name. Author Jordi Díaz-Manera was erroneously presented as Jorge Alberto Diaz Manera. The correct author name has been included in the author list of this Correction article.

Eight years after an international workshop on myotonic dystrophy patient registries: case study of a global collaboration for a rare disease.

BACKGROUND: Myotonic Dystrophy is the most common form of muscular dystrophy in adults, affecting an estimated 10 per 100,000 people. It is a multisystemic disorder affecting multiple generations with increasing severity. There are currently no licenced therapies to reverse, slow down or cure its symptoms. In 2009 TREAT-NMD (a global alliance with the mission of improving trial readiness for neuromuscular diseases) and the Marigold Foundation held a workshop of key opinion leaders to agree a minimal dataset for patient registries in myotonic dystrophy. Eight years after this workshop, we surveyed 22 registries collecting information on myotonic dystrophy patients to assess the proliferation and utility the dataset agreed in 2009. These registries represent over 10,000 myotonic dystrophy patients worldwide (Europe, North America, Asia and Oceania). RESULTS: The registries use a variety of data collection methods (e.g. online patient surveys or clinician led) and have a variety of budgets (from being run by volunteers to annual budgets over €200,000). All registries collect at least some of the originally agreed data items, and a number of additional items have been suggested in particular items on cognitive impact. CONCLUSIONS: The community should consider how to maximise this collective resource in future therapeutic programmes.

Polymerase chain reaction-guided diagnosis of infective keratitis - a hospital-based study.

PURPOSE: To compare polymerase chain reaction (PCR) to microbial culture and smear for detection and identification of bacterial and fungal pathogens in suspected microbial keratitis. MATERIALS AND METHODS: Corneal scrapings from 88 patients with suspected infectious keratitis were subjected to routine bacterial culture and sensitivity, Gram's stain, fungal culture; potassium hydroxide (KOH) wet mount, and PCR. PCR was performed with primer pairs targeted to the 16S and 18S r RNA gene. The result of the PCR was compared with conventional culture and Gram staining method. RESULTS: By broad-range PCR, 40 (45.45%) cases were positive for fungi (90.9% sensitivity), 26 (29.5%) were culture positive (59.09% sensitivity), 29 (33%) of all patients were positive for bacteria by broad-range PCR (87.9% sensitivity) and 19 (21.6%) were culture positive (57.58% sensitivity). The time taken for PCR assay was 4-8 h whereas positive fungal cultures took 2-10 days and bacterial culture from 2 to 4 days. Smears were positive for fungi in 29 eyes (33% of cases, 65.91% sensitivity) and for bacteria in 11 eyes (12.5% of cases, 33.33% sensitivity). CONCLUSIONS: DNA amplification with universal primers is a promising diagnostic tool in cases of infectious keratitis where routine laboratory culture failed to identify the pathogen. PCR may be performed in cases where the results of corneal scraping stains are negative without waiting for the results of the culture.

High rates of intestinal colonization with extended-spectrum lactamase-producing Enterobacteriaceae among healthy individuals.

BACKGROUND: Infections caused by extended-spectrum ß-lactamase (ESBL)-producing bacteria become an emerging problem in the community setting in many parts of the world. OBJECTIVE: The objective of the study was to determine fecal carriage of ESBL-producing organisms in a community setting. METHODS: A total of 632 fecal specimens from healthy individuals were screened for ESBL using the agar screening test with MacConkey agar plates supplemented with 1 µg/mL of cefotaxime for selection of ESBL-producing strains and confirmed by the Clinical Laboratory Standards Institute combined disk method. RESULTS: Four hundred isolates (63.3%) were ESBL producers. Two hundred eighty-five isolates (71.25%) of them were Escherichia coli and 96 (24.0%) Klebsiella pneumoniae. CONCLUSION: We concluded that the community could be a reservoir of these ESBL-producing bacteria and enzymes.

Carriage of Staphylococcus aureus in the nose of patients on regular dialysis treatment using hemodialysis catheters.

In the hemodialysis population, the incidence of Staphylococcus aureus colonization has been documented to be as high as 80%; effective prophylaxis of vascular access infection and bacteremia is a worthwhile goal in the management of hemodialysis population. Surveillance of 50 hemodialysis patients for S. aureus-positive nasal cultures was performed by monthly nasal swabs over a 12-month period. All patients were performing dialysis using hemodialysis catheters thrice weekly. All positive cultures were treated with a prophylactic antibiotic regimen. Thirty-one patients (62%) had one or more positive cultures. The surveillance period was longer in the S. aureus nasal carriers (p < 0.01). The frequency of positive cultures correlated with the duration of surveillance (p < 0.05). The incidence of S. aureus bacteremia was greater in patients with three or more positive cultures (p < 0.05). This study suggests that continuous surveillance for S. aureus nasal colonization is essential to properly identify all hemodialysis patients using catheters at risk of developing S. aureus bacteremias.