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Diabetic myonecrosis is an under-recognized and under-reported complication of longstanding diabetes. In this case series, we have attempted to report the clinical and radiological characteristics of six patients with diabetic [...]

Keywords: dystrophin, sarcoglycan, dysferlin, lamin A/C, nitric oxide synthase Abstract To withstand the rigors of contraction, muscle fibers have specialized protein complexes that buffer against mechanical stress and a multifaceted repair system that is rapidly activated after injury. Genetic studies first identified the mechanosensory signaling network that connects the structural elements of muscle and, more recently, have identified repair elements of muscle. Defects in the genes encoding the components of these systems lead to muscular dystrophy, a family of genetic disorders characterized by progressive muscle wasting. Although the age of onset, affected muscles, and severity vary considerably, all muscular dystrophies are characterized by muscle necrosis that overtakes the regenerative capacity of muscle. The resulting replacement of muscle by fatty and fibrous tissue leaves muscle increasingly weak and nonfunctional. This review discusses the cellular mechanisms that are primarily and secondarily disrupted in muscular dystrophy, focusing on membrane degeneration, muscle regeneration, and the repair of muscle.

The effects of pH on the pore-forming Clostridium septicum alpha-toxin that causes myonecrosis was assessed at pH 5.0, 7.0 and 9.0 by measuring circular dichroism and its biological activity. Incubation of the toxin at pH 5.0 increased the hemolytic activity measured in murine red blood cells. On the other hand, incubation of the toxin at pH 9.0 drastically reduces the biological activity of the toxin by five-fold. This study presents the first evidence of the effect of pH on the functional properties of alpha-toxin directly related to the common disease caused by C. septicum in animals and humans i.e. traumatic and non traumatic gas gangrene. Key words: Clostridium septicum; alpha-toxin, hemolytic activity; lethality; pH, INTRODUCTION Alpha-toxin is a major exotoxin produced by strains of the Gram-positive bacterium Clostridium septicum. As a result of alpha-toxin, C. septicum has been implicated as a cause of exogenous [...]

The The mdx mouse is an animal model for Duchenne muscular dystrophy. Mdx mice fed a 12% NaCl diet from birth up to 20 days of age (mdx-Na mice) had an ~50% reduction in serum creatine kinase (CK) activity compared with mdx mice fed a standard diet. Most notably, necrotic fibers in tibialis anterior (TA) muscle of mdx-Na mice were reduced by 99% and were similar in control mice. These mdx mice displayed significantly elevated blood [Ca.sup.2+] and [Na.sup.+] levels, while the total calcium content of their TA muscle was reduced to the level of control mice. In addition, mdx-Na mice had elevated zinc and magnesium contents in their TA muscle. These results suggest that elevated serum [Na.sup.+] leads to [Ca.sup.2+] extrusion from muscle via the [Na.sup.+]/[Ca.sup.2+] exchanger causing a decrease in intracellular [Ca.sup.2+] levels and an increase in blood [Ca.sup.2+] levels. Extracellular [Ca.sup.2+] and, in addition, [Zn.sup.2+] and [Mg.sup.2+] might also contribute to the stabilization of the cell membrane. Other possibilities explaining the surprisingly efficacious beneficial effect of dietary sodium exist and are discussed. therapy; calcium and zinc; potassium; blood; serum creatine kinase activity

Ischemia induced in one of the paired gracilis muscles signals the contralateral muscle to produce more heat shock proteins that can minimize any damage caused by a subsequent ischemic episode. In this study, the gracilis muscle on one dog leg was subjected to 5 hours of ischemia and reperfused, and then the same muscle on the other leg was subjected to the same treatment. The second muscle exhibited an increase in heat shock proteins that minimized the extent of muscle death caused by ischemia compared to the muscle that first suffered ischemia.

Byline: U. Vogel (1), B. Bultmann (1), T. Wanner (2) Keywords: Fibrillation; Defibrillation Muscle damage; Electroporation Abstract: A 37-year-old Italian male developed a myocardial infarct with subsequent ventricular fibrillation. He was defibrillated seven times with up to 360 Joules. Thirteen days later the patient died of recurrent myocardial infarct due to thrombotic occlusion of the left circumflex coronary artery. At autopsy, necrosis of the right pectoralis muscle was observed. Electroporation is the pathogenetic mechanism of skeletal muscle damage due to multiple defibrillations with high energy levels. Author Affiliation: (1) Institute of Pathology, University of Tubingen, Liebermeisterstrasse 8, D-72076, Tubingen, Germany (2) Department of Internal Medicine, Hospital of Boblingen, Boblingen, Germany Article History: Registration Date: 23/03/2009 Received Date: 08/01/1998 Accepted Date: 15/04/1998

To link to full-text access for this article, visit this link: http://dx.doi.org/10.1016/j.ahj.2006.02.026 Byline: Hitinder S. Gurm (a), Yuri Breitbart (b), Deepak Vivekanathan (a), Michael H. Yen (a), Robert Fathi (a), Khaled M. Ziada (a), Patrick L. Whitlow (a), Stephen G. Ellis (a) Abstract: Incidence of myonecrosis in patients undergoing rotational atherectomy was evaluated by preprocedural statin use. The incidence of any myonecrosis (24.1% vs 52.3%, P < .001) or significant myonecrosis (7.5% vs 21.8%, P < .001) was significantly lower among patients pretreated with statins. This difference remained significant after multivariable and propensity adjustment. Author Affiliation: (a) Department of Cardiovascular Medicine, Cleveland Clinic Foundation, Cleveland, OH (b) Department of Computer Science, Kent State University, Kent, OH Article History: Received 23 May 2005; Accepted 11 February 2006 Article Note: (footnote) This study had no external funding and none of the authors have a conflict of interest. All work presented in this analysis was preformed at the Cleveland Clinic Foundation.

Clostridium myonecrosis is a rare and deadly infection that progresses very rapidly; thus, prompt diagnosis and treatment is vital. In adults, clostridial myonecrosis used to be a well-known complication of war wounds. Today, it is usually seen in settings of trauma, surgery, malignancy, skin infections/burns, and septic abortions. More recently, cases of nontraumatic or spontaneous clostridial myonecrosis have been reported in both adults and children. Clostridium perfringens and Clostridium septicum are responsible for the majority of the clinically relevant infections. Higher mortality rates are seen when C septicum is the causative agent. Here we present a child who survived a severe case of C septicum myonecrosis involving both abdominal and thoracic cavities. This rare infection has a high mortality rate and might be easily misdiagnosed in children, even by experienced clinicians, because of its nonspecific presentation. We also review all reported pediatric cases of C septicum infection and myonecrosis and discuss the surgical and medical interventions associated with improved survival. We identified a total of 47 cases of C septicum infection; of these, 22 (47%) were cases of C septicum associated with myonecrosis. Several factors, if available, were analyzed for each case: age, gender, infection location, previous diagnoses, presenting signs and symptoms, neutropenia, gross pathology of the colon, antibiotic use, surgical intervention, and final outcome. We found that conditions related with C septicum infection in children can be grouped into 3 major categories: patients with neutrophil dysfunction; patients with associated bowel ischemia; and patients with a history of trauma. Malignancies were found in 49% of the cases, cyclic or congenital neutropenia in 21%, hemolytic-uremic syndrome in 11%, structural bowel ischemia in 4%, and local extremity trauma in 6%. In addition, 6% of the cases had no known underlying disorder. Abdominal symptoms including vomiting, diarrhea, blood per rectum, abdominal pain, anorexia, and/or acute abdomen, were reported in 85% of the children. Fever was also a common finding. The mainstay of treatment for C septicum infection was parenteral antibiotics and/or surgical intervention. The mortality rate for children with C septicum infection and myonecrosis was 57% and 59%, respectively. Although 82% of all cases received antibiotics, only 43% underwent therapeutic surgical intervention. Several clinical factors were found to be associated with improved survival. Only 35% of the children with gastrointestinal tract involvement survived, compared with 86% of the children without gastrointestinal tract involvement. The survival rates for other conditions ranged from 0% to 50%. One hundred percent survival was reported in patients with no previously diagnosed conditions and those with infections resulting from trauma to the extremities. All survivors received antibiotic treatment, compared with only 68% of the nonsurvivors. Most survivors (84%) underwent therapeutic surgical intervention, compared with only 12% of nonsurvivors. Other treatments were used adjunctively, including hyperbaric oxygen, granulocyte colony-stimulating factor, granulocyte transfusions, and intravenous immunoglobulin. C septicum infections in children are often fatal; thus, one needs to have a high index of suspicion in at-risk patients. This review describes who these patients are, their clinical presentation, and the therapeutic strategies associated with improved survival. KEY WORDS. Key Words: Clostridium septicum, myonecrosis, gas gangrene, necrotizing enterocolitis, hyperbaric oxygenation, granulocyte colony-stimulating factor, intravenous immunoglobulin, neutropenia, malignancy, hemolytic-uremic syndrome.

Extremity pain is a common complaint in adolescents. Pain out of proportion to examination findings should raise suspicion of deep tissue infection. Clostridial myonecrosis is a rapidly progressive disease consisting of muscle necrosis and systemic toxicity. It is usually seen in elderly and immunocompromised patients. Here we report a case of clostridial myonecrosis in an adolescent male. URL: www. pediatrics.org/cgi/doi/10.1542/peds.2004-2876; infection, pain.