Adolescent Hyperuricemia with Lipid Storage Myopathy: A Clinical Study.

BACKGROUND In this study, we investigated the clinical and pathological features of patients with lipid storage myopathy (LSM) complicated with hyperuricemia, to improve clinicians' understanding of metabolic multi-muscular disorder with metabolic disorders, and to reduce the risk of missed diagnosis of LSM. MATERIAL AND METHODS From January 2005 to December 2017, 8 patients underwent muscle biopsy and diagnosed by muscle pathology and genetic testing in our hospital. All 8 patients were in compliance with LSM diagnosis. We collected data on the patient's clinical performance, adjuvant examination, treatment, and outcomes to provide a comprehensive report and description of LSM patients with hyperuricemia. RESULTS All patients were diagnosed as having ETFDH gene mutations. The main clinical manifestations of patients were chronic limb and trunk weakness, limb numbness, and muscle pain. The serum creatine kinase (CK) values in all patients were higher than normal values. Electromyography showed 3 cases of simple myogenic damage and 3 cases of neurogenic injury. Hematuria metabolic screening showed that 2 patients had elevated glutaric aciduria, and 1 patient had elevated fatty acyl carnitine in the blood. All patients were given riboflavin treatment, and the clinical symptoms were significantly improved, and 3 patients returned to normal uric acid levels after treatment. Pathological staining showed an abnormal deposition of lipid droplets in muscle fibers. CONCLUSIONS If an adolescent hyperuricemia patient has abnormal limb weakness, exercise intolerance, and elevated serum CK values, clinicians need to be highly alert to the possibility of LSM. Early diagnosis and treatment of LSM should improve the clinical symptoms and quality of life and reduce complications.

A novel DMD splicing mutation found in a family responsible for X-linked dilated cardiomyopathy with hyper-CKemia.

This study was aimed to detect a new mutation responsible for X-linked dilated cardiomyopathy with hyper-CKemia.We studied a proband who presented with cardiac symptoms with hyper-CKemia, but no clinical skeletal involvement in physical examination, laboratory tests, electromyography, echocardiography, and magnetic resonance imaging (MRI) of cardiac muscles. Muscle biopsy for histopathology and immunohistochemistry for accessing sarcolemma changes. The next-generation sequencing and bioinformatics analysis were performed on the patient and Sanger sequencing was confirmed on the other 6 unaffected families.The clinic investigations illustrated a dilated cardiomyopathy. Histopathology and immunohistochemistry showed dystrophic changes and an obvious reduction of dystrophin-N and δ-sarcoglycan, respectively. One hemizygous splicing pathogenic mutation c.31 + 1G > C of exon 1 in the DMD gene (chrX33229398, NM_00 4006) was finally identified in the patient and his nephew, but it was carried in his mother and sister.A novel small mutation was identified at the first exon-intron boundary splicing site by next-generation sequencing and bioinformatics analysis.

A novel mutation in the DYSF gene in a patient with a presumed inflammatory myopathy.

Dysferlinopathy, a progressive muscular dystrophy, results from mutations in the Dysferlin gene (DYSF, MIM*603009). Traditional diagnosis relies on the reduction or absence of dysferlin. However, altered dysferlin has been observed in other myopathies, leading to a precise diagnosis through molecular genetics. In this study, we report a patient who was previously misdiagnosed as inflammatory myopathy based on routine clinicopathological examinations alone. However, muscle biopsy specimens were analyzed further by immunohistochemistry of muscular dystrophy-related proteins, and gene-targeted next generation sequencing (NGS) was used to correctly identify muscular dystrophy. DNA was sequenced with NGS and the detected mutation was verified by Sanger sequencing. Our targeted NGS found a novel missense mutation (c.5392G > A) in the DYSF gene, allowing correct diagnosis of LGMD2B in our patient. We discovered of a novel missense mutation in the DYSF gene and have broadened the DYSF mutation spectrum, which may be correlated in patients with presumed dysferlinopathy, especially when lymphocytic infiltration is observed.

Adeno-associated virus serotype 9 mediated vascular endothelial growth factor gene overexpression in mdx mice.

Duchenne muscular dystrophy (DMD) is a fatal neuromuscular disease caused by the absence of dystrophin. Vascular endothelial growth factor (VEGF) is a heparin-binding dimeric glycoprotein and principal angiogenic factor stimulating the migration, proliferation and expression of various genes in endothelial cells. Recently, VEGF was demonstrated to exhibit an antiapoptotic and direct myogenic effect, as well as to enhance muscle force restoration subsequent to traumatic injury. Therefore, the present study attempted to assess the muscle damage of VEGF overexpression in mdx mice. Adeno-associated virus serotype 9 (AAV9)-VEGF was administered intravenously to mdx mice. At 4 weeks after injection, VEGF was observed to be upregulated in the tibialis anterior muscle. In addition, the serum creatine kinase levels were significantly reduced and fatigue was slowed down, whereas the limb grip strength and weight of mice were markedly increased compared with the saline-treated mdx mice. Furthermore, significantly reduced inflammation and necrosis areas were observed in the muscle tissues of mice in the AAV9-VEGF group. These results suggested that AAV9-mediated VEGF gene overexpression was able to improve the muscle damage in mdx mice.