Piomiositis en pediatría: experiencia de 10 años en un hospital pediátrico de alta complejidad en Argentina / Pyomyositis in pediatrics: 10-year experience in a high-complexity pediatric hospital in Argentina

INTRODUCCIÓN: La piomiositis es una infección bacteriana agudasubaguda del músculo esquelético. OBJETIVO: Estimar la incidencia de piomiositis en pacientes internados, describir e identificar factores de riesgo para bacteriemia y hospitalización, y evaluar diferencias entre Staphylococccus aureus sensible y resistente a meticilina (SASM y SARM). PACIENTES Y MÉTODOS: Estudio descriptivo, retrospectivo, observacional, con pacientes de 1 mes a 18 años de edad, internados entre el 1 de enero de 2008 y 31 de diciembre de 2018. Variables: sexo, edad, hacinamiento en el hogar, existencia de lesión previa, estacionalidad, localización anatómica e imágenes, antibioterapia previa, estadio clínico, parámetros de laboratorio, cultivos y antibiograma, días de tratamiento intravenoso (IV), de internación, de fiebre y bacteriemia. RESULTADOS: Se incluyeron 188 pacientes. Incidencia: 38,9 casos / 10.000 admisiones (IC95 % 33,7 - 44,9). Días de internación y tratamiento IV: 11 (RQ 8-15 y RQ 8-14, respectivamente). El desarrollo de bacteriemia se asoció a PCR elevada (p = 0,03) y fiebre prolongada (p < 0,001). No hubo diferencias en la evolución y parámetros de laboratorio entre SASM y SARM. La leucocitosis (p = 0,004), neutrofilia (p = 0,005) y bacteriemia (p = 0,001) se asociaron a mayor estadía hospitalaria. CONCLUSIONES: Este estudio recaba la experiencia de más de 10 años de niños internados con diagnóstico de piomiositis y proporciona información sobre sus características. Se describen parámetros asociados a bacteriemia y estadía hospitalaria.

BACKGROUND: Pyomyositis is an acute-subacute bacterial infection of skeletal muscle. AIM: To estimate the incidence of pyomyositis in hospitalized patients, describe and identify risk factors for bacteremia and hospitalization, and evaluate differences between MSSA and MRSA. METHODS: Descriptive, retrospective, observational study with patients aged 1 month to 18 years hospitalized between January, 1, 2008 and December 1, 2018. Variables: sex, age, home overcrowding, previous injury, seasonality, anatomical location and images, previous antibiotherapy, clinical stage, laboratory, cultures and antibiogram, days of intravenous (IV) treatment, hospitalization, fever and bacteremia. RESULTS: 188 patients were included. Incidence: 38.9 cases/10,000 admissions (95% CI 33.7 - 44.9). Days of hospitalization and IV treatment: 11 (RQ 8-15 and RQ 8-14, respectively). The development of bacteremia was associated with elevated CRP (p = 0.03) and prolonged fever (p < 0.001). There were no differences in the evolution and laboratory parameters between MSSA and MRSA. Leukocytosis (p = 0.004), neutrophilia (p = 0.005), and bacteremia (p = 0.001) were associated with a longer hospital stay. CONCLUSIONS: This study collects the experience of more than 10 years of hospitalized children diagnosed with pyomyositis and provides information on its characteristics. Parameters associated with bacteremia and hospital stay are described.

Recurrent polymyositis-associated lung disease after lung transplantation.

The association between interstitial lung disease and polymyositis/dermatomyositis is well known. It severely affects patients' quality of life, worsens prognosis and represents a major risk factor for premature death. Current treatment is unclear and therapeutic options are based on case series. We report the case of a 15-year old female diagnosed with end-stage lung disease associated to polymyositis who received a double lung transplant after 20 days of extracorporeal membrane oxygenation. She died 9 months later and microscopic post-mortem findings revealed recurrence of interstitial lung disease. This is the first time that recurrence of polymyositis-associated lung disease following lung transplantation is described in the literature.

Is lung transplantation a valuable therapeutic option for patients with pulmonary polymyositis? Experiences from the Leuven transplant cohort.

Interstitial lung disease (ILD) is one of the most critical complications associated with idiopathic inflammatory myopathies (IIM). If medical treatment fails, the only option is lung transplantation (LTx), however, this is still controversial mainly because the outcome is unknown. This case series compared patients with IIM who underwent transplantation in the University Hospitals of Leuven among a total of 90 LTxs for ILD between January 2004 and August 2013. From the 5 IIM patients with associated ILD there were 4 males and 1 female. The mean age at transplantation was 54.4 ± 4.3 years. Three patients underwent sequential single lung (SSLTx) and 2 underwent single lung transplantation (SLTx). Their mean pre-LTx % predicted forced expiratory volume in the first second (FEV1) was 42.8 ± 7.5%, forced vital capacity (FVC) was 49.8 ± 9.6%, total lung capacity (TLC) was 60.8 ± 8.1%, and transfer coefficient for carbon monoxide (DLCO) was 35.1 ± 9.3%. Mean 6-minute walking test (SMWT) before LTx was 316.0 ± 146 meters. In one patient there was an acute rejection (AR) after 20 days. No lymphocytic bronchiolitis (LB) nor chronic rejection was observed. The 1-year survival rate was 100%, and the 2- and 5-year survival rates were 75% (follow-up period of 32.6 ± 4.4 months) compared with 86%, 67%, and 58%, respectively, for patients undergoing LTx for idiopathic pulmonary fibrosis (IPF) (follow-up period of 35.2 ± 3.9) and 86%, 63%, and 57%, respectively, for patients undergoing LTx for non-IPF non-IIM ILD (follow-up period of 40.6 ± 20.5 months). LTx could be a valid option in well-selected patients with ILD related to IIM, yielding a good postoperative course and acceptable 1-, 2-, and 5-year survival rates, compared with patients undergoing LTx for IPF and non-IPF non-IIM-related ILD.

Polymyositis in solid organ transplant recipients receiving tacrolimus.

Tacrolimus, also known as FK506, is an immunosuppressive agent widely used for the prevention of acute allograft rejection in organ transplantation and for the treatment of immunological diseases. This study reports two male patients who underwent solid organ transplantation (liver and kidney). After transplant, the patients received continuous immunosuppressive therapy with oral tacrolimus and later presented clinical manifestations and laboratory signs of myopathy. Muscle biopsies of both patients clearly documented an inflammatory myopathy with the histological features of polymyositis including CD8+ T cells which invaded healthy muscle fibers and expressed granzyme B and perforin, many CD68+ macrophages and MHC class I antigen upregulation on the surface of most fibers. Because of the temporal association while receiving tacrolimus and since other possible causes for myopathy were excluded, the most likely cause of polymyositis in our patients was tacrolimus toxicity. We suggest that patients on tacrolimus should be carefully monitored for serum CK levels and clinical signs of muscle disease.

Thoracic epidural anesthesia for a polymyositis patient undergoing awake mini-thoracotomy and unroofing of a huge pulmonary bulla.

General anesthesia with one-lung ventilation is a conventional anesthetic strategy for most chest surgery, including resection of pulmonary bullae. However, this anesthetic management may cause alveolar barotrauma, hemodynamic instability, pulmonary atelectasis and long-term ventilator dependency. Here, we report a 64-year-old female with polymyositis and bronchiolitis obliterans organizing pneumonia who was scheduled for surgical intervention for a huge pulmonary bulla over the right upper lung. Under thoracic epidural anesthesia, with the patient maintaining clear consciousness and spontaneous breathing, a mini-thoracotomy was accomplished to unroof and partially resect the bulla. There were no perioperative complications, and the patient was satisfied with the anesthetic care. Pulmonary function tests and daily physical performance also improved postoperatively.

A case of polymyositis associated with adrenal carcinoma.

The association between idiopathic inflammatory myositis and cancer is well recognized. Most descriptions have been of dermatomyositis-associated cancer, however, a few have been of polymyositis-associated adrenal cancer. Here, we report a 69-year-old man in whom polymyositis-associated adrenal cancer was diagnosed. The patient complained of difficulty with walking and with standing unassisted. Physical examination and electrophysiological studies revealed an abnormality of the proximal muscles. Serum levels of creatine kinase and lactic dehydrogenase were increased. Imaging studies showed a solid tumor measuring 14 x 9 cm in the retroperitoneum. After surgical excision of the tumor, including the left kidney, the serum levels of creatine kinase and lactic dehydrogenase normalized, and symptoms of myositis disappeared.

Failure to awaken after general anesthesia due to cerebrovascular events.

Failure to awaken after general anesthesia is a rare complication that may be caused by residual drug effect, systemic abnormalities, or neurologic injury. Failure to awaken often is initially attributed to residual drug effect, potentially delaying correct diagnosis. Three cases of failure to awaken because of neurologic injury are reviewed. Differential diagnosis of failure to awaken is discussed, and the importance of distinguishing pathologic causes from residual anesthetic is stressed.

Inflammatory myopathy causing pharyngeal dysphagia: a new entity.

Seven patients presented to our swallowing center with solid food dysphagia. The age range at presentation was 69 to 90 years. All patients had normal findings on neurologic evaluation, and in those patients undergoing electromyography and nerve conduction studies, results of all such tests were also normal. Pooling of saliva in the pharyngeal recesses was noted on fiberoptic laryngoscopy in most cases. The swallowing videofluoroscopy findings were strikingly similar. All patients had a prominent cricopharyngeus muscle, and some had a prominence in a more proximal portion of the inferior constrictor muscle. All patients had decreased epiglottic tilt and moderate or severe residue in the pharyngeal recesses. Three patients underwent pharyngoesophageal sphincter myotomy. Biopsies of the omohyoid and cricopharyngeus muscles showed inflammatory myopathy with no evidence of inclusion bodies. This is a distinct clinical entity defined by isolated pharyngeal dysphagia in elderly patients with a unique videofluoroscopic appearance and pharyngeal myopathy.