[Viral myositis, a pediatric case report]. / Miositis viral, reporte de un caso pediátrico.

Acute viral myositis is a complication after a viral infection mainly caused by Influenza A and B viruses. It is characterized as a transitory, sudden, self-limiting and benign inflammatory process. It usually affects preschool and school children presenting bilateral pain and sensitivity in the muscle groups of the lower limbs without alteration in the neurological examination. It can affect the gait or standing. The main complication is rhabdomyolysis, which is why clinical followup and values of creatine phosphokinase must be done. We present the case of a school-age child diagnosed with acute viral myositis. Because it is not a frequent entity and its incidence in Latin America is unknown, we consider important to report the case and review the topic, as its clinical course is benign, easily treated, and its knowledge can avoid unnecessary studies and hospitalizations.

La miositis viral aguda es una complicación posterior a una infección viral causada, principalmente, por virus influenza A y B. Se caracteriza por ser un proceso inflamatorio transitorio, súbito, autolimitado y benigno. Generalmente, afecta a niños preescolares y escolares, que presentan dolor bilateral y sensibilidad en los grupos musculares de los miembros inferiores sin alteración en el examen neurológico. Puede generar alteración de la marcha o de la bipedestación. Su principal complicación es la rabdomiólisis, por lo que se debe hacer un seguimiento clínico y de los valores de la creatinfosfoquinasa. Se presenta el caso de un niño en edad escolar con diagnóstico de miositis viral aguda. Debido a que es poco frecuente y su incidencia en Latinoamérica es desconocida, se considera importante el reporte del caso y la revisión del tema, ya que su curso es benigno, de fácil manejo, y su conocimiento evita estudios y hospitalizaciones innecesarias.

Ecstasy induces reactive oxygen species, kidney water absorption and rhabdomyolysis in normal rats. Effect of N-acetylcysteine and Allopurinol in oxidative stress and muscle fiber damage.

BACKGROUND: Ecstasy (Ec) use produces hyperthermia, excessive sweating, intense thirst, an inappropriate antidiuretic hormone secretion (SIADH) and a multisystemic toxicity due to oxidative stress (OS). Intense thirst induces high intake of pure water, which associated with SIADH, usually develops into acute hyponatremia (Hn). As Hn is induced rapidly, experiments to check if Ec acted directly on the Inner Medullary Collecting Ducts (IMCD) of rats were conducted. Rhabdomyolysis and OS were also studied because Ec is known to induce Reactive Oxygen Species (ROS) and tissue damage. To decrease OS, the antioxidant inhibitors N-acetylcysteine (NAC) and Allopurinol (Allo) were used. METHODS: Rats were maintained on a lithium (Li) diet to block the Vasopressin action before Ec innoculation. AQP2 (Aquaporin 2), ENaC (Epitheliun Sodium Channel) and NKCC2 (Sodium, Potassium, 2 Chloride) expression were determined by Western Blot in isolated IMCDs. The TBARS (thiobarbituric acid reactive substances) and GSH (reduced form of Glutathione) were determined in the Ec group (6 rats injected with Ec-10mg/kg), in Ec+NAC groups (NAC 100mg/Kg/bw i.p.) and in Allo+Ec groups (Allo 50mg/Kg/i.p.). RESULTS: Enhanced AQP2 expression revealed that Ec increased water transporter expression, decreased by Li diet, but the expression of the tubular transporters did not change. The Ec, Ec+NAC and Allo+Ec results showed that Ec increased TBARS and decreased GSH, showing evidence of ROS occurrence, which was protected by NAC and Allo. Rhabdomyolysis was only protected by Allo. CONCLUSION: Results showed that Ec induced an increase in AQP2 expression, evidencing another mechanism that might contribute to cause rapid hyponatremia. In addition, they showed that NAC and Allo protected against OS, but only Allo decreased rhabdomyolysis and hyperthermia.

Clinical features of rhabdomyolysis after open and laparoscopic Roux-en-Y gastric bypass.

BACKGROUND: Rhabdomyolysis (RML) is caused by muscle injury, this may cause kidneys overload and lead to acute renal failure (ARF). The risk factors for RML in bariatric surgery (BS) are operative time (OT) >4 h and high BMI. The frequency of RML in BS varies from 12.9 to 37.8%. This study has the objective of describing the characteristics associated with RML and ARF in BS. METHODS: We studied retrospectively 114 patients submitted to BS. Criteria for RML were CPK level >950 IU/l (five times the normal value). The variables were BMI, OT, age, intraoperative hydration and diuresis, CPK, creatinine, arterial hypertension, peripheric vascular disease, diabetes, open and laparoscopic techniques--inclusion criteria: patients submitted to gastric bypass; exclusion: renal failure and statins use. RESULTS: RML incidence was 7%. The factors associated with RML in the bivariate analysis were hepatic steatosis, high BMI, high weight, higher excess weight, and prolonged OT. The risk factor for RML in the multivariate analysis was BMI > or = 50 kg/m2. When the OT was below 2 h the incidence of RML was zero, but this was not significant in the multivariate analysis. The factors associated with a higher risk of CPK elevation (multivariate analysis) were hypertension and open technique. CONCLUSION: BS is safe, with low incidence of RML/ARF. High BMI is associated with a higher risk of RML. Probably a longer OT is associated with a higher risk of RML not statistically demonstrated in this study. The factors associated with a higher risk of CPK elevation were hypertension and open technique.

Rhabdomyolysis after bariatric surgery.

BACKGROUND: Rhabdomyolysis is a potential threat after bariatric surgey. The severity ranges from asymptomatic elevations of serum muscle enzyme levels to life-threatening cases associated with muscle necrosis, compartment syndrome, acute renal failure and cardiac arrest. METHODS: We studied 98 consecutive obese patients who underwent primary uncomplicated bariatric surgery during a 1-year period. A database was created for all patients (sex, age, BMI, duration of the operation); serum creatinine phosphokinase (CPK) was systematically measured before surgery and on the first and second postoperative day. RESULTS: The study sample consisted of 35 males (35.7%) and 63 females (64.3%) with preoperative CPK level 156.6 +/- 41.1 U/L (40 to 220), 24 hours postoperatively 1,075.2 +/- 596.5 U/L, (85 to 2,790 U/L) and 48 hours postoperatively 967.3 +/- 545.3 U/L (79 to 2,630). There was no difference in mean BMI (P=0.1) and mean duration of operation (P=0.5) between males and females. However, a statistically significant difference in mean elevation of CPK between males and females (P=0.003) was found. The variables sex, age, weight and duration of surgery were analyzed by multivariate logistic regression, but did not show a statistically significant difference. CONCLUSION: Rhabdomyolysis is a potentially fatal complication of surgical procedures in obese patients, and can be minimized with simple measures such as additional padding, aggressive hydration and urine alkalinization. Diagnosis requires a high level of physician awareness.

Prevention of rhabdomyolysis in bariatric surgery.

BACKGROUND: Rhabdomyolysis (RML) is a clinical and biochemical syndrome caused by skeletal muscle necrosis that results in extravasation of toxic intracellular contents from the myocytes into the circulatory system. Postoperative RML in bariatric surgery occurs with various non-physiological surgical positions, with prolonged muscle compression. The potential consequences may lead to death. The purpose of this study is to review its pathophysiology and the best ways to prevent RML in bariatric surgery. METHODS: We searched the literature and reviewed all relevant articles, by searching for the keywords: rhabdomyolysis, morbid obesity, prevention and bariatric surgery, giving a total of 39 articles. RESULTS: Prevention may be enhanced by careful padding on the operative table at all pressure-points. Changing patient position, both intraoperatively and postoperatively, also reduces RML. A potential new solution to decrease the longer operative time and avoid RML is to perform the bariatric operation in two stages. Another way to limit the duration of surgery in high-risk patients is to alert surgeons not to select super-obese high-risk patients early in the learning curve. CONCLUSION: As RML is an important and potentially fatal complication of bariatric surgery, the best way to avoid it is effective prevention. More research on this subject is necessary.