Utilidad de Trimetoprima-sulfametoxazol en épocas de S. aureus meticilino resistente de la comunidad / Usefulness of trimethoprim-sulfamethoxazole in times of community-acquired methicillin-resistant S. aureus.

Trimetoprima-sulfametoxazol (TMP-SMX) tiene actividad in vitro contra cepas de Staphylococcusaureus, en especial las cepas resistentes a la meticilina de la comunidad (SAMR-Co), Éste es considerado un antibiótico útil debido a su bajo costo, amplio espectro y posibilidad de administración por vía oral dada su adecuada biodisponibilidad y sabor agradable. Se realizó esta revisión narrativa de la literatura para evaluar el uso de TMP-SMX en comparación con otras opciones disponibles en el tratamiento de las infecciones por SAMR-Co en niños (AU)

Trimethoprim/sulfamethoxazole (TMP-SMX) has in vitro activity against Staphylococcus aureus, especially against community-acquired methicillin-resistant (CAMR) strains. It is considered to be a useful antibiotic because of its low cost, broad spectrum, and possibility of oral administration because of its adequate bioavailability and agreeable flavor. A review of the literature was performed to evaluate the use of TMP-SMX compared to available options for the treatment of CAMR infections in children (AU)

Estudio descriptivo de infecciones osteo-articulares en niños en tiempos de Staphylococcus aureus resistente a meticilina de la comunidad (SARM-Co) / Descriptive study of bone and joint infections in children in times of community-acquired methicillin- resistant Staphylococcus aureus (CA-MRSA)

Background: Bone and joint infections (BJI) are relatively common in children, and community -acquired methicillin resistant Staphylococcus aureus (CA-MRSA) is the leading cause in some countries. Aim: To evaluate epidemiological data, clinical and microbiological features and outcome of BJI. Methods: A prospective descriptive study was conducted. Results: 40 patients (p) completed the study. Bacterial cultures were positives in 30 p (75%): CA-MRSA was found in 19 p, methicillin-sensitive S. aureus in 6 p, and others in 5 p. Cultures were negatives in 10 p (25%). Median treatment duration was 28 days (r: 21-40 d); Analyzing patients with CA-MRSA positive cultures separately, initial CRP was higher (Md 76 vs 50 mg/L, p < 0.02), normalization occurred later (Md 14 days vs 7days, p < 0.03), and duration of treatment (Md 32 days vs 23, p < 0.004) as well as hospital stay (Md 9 days vs 7, p = 0.12) were longer. Sequelae were present in 3 p and 1 relapsed: All of them with CA-SAMR. Conclusion: CA-MRSA was the leading cause of BJI and was associated with higher CRP on admission, later normalization and longer treatment duration. Complications as drainage requirement, and sequelae were common in those p.

Introducción: Las infecciones osteo-articulares (IOA) son relativamente comunes en los niños, siendo la infección por Staphylococcus aureus resistente a meticilina de la comunidad (SARM-Co) una de las más frecuentes. Objetivo: Evaluar los datos epidemiológicos, características clínicas, microbiológicas y de evolución en niños con IOA. Métodos: Estudio descriptivo prospectivo. Resultados: Se incluyeron 40 pacientes (p). Los cultivos fueron positivos en 30 p (75%). Se aisló SARM-Co en 19 p; S. aureus sensible a meticilina en 6 p; otros microorganismos en 5 p. La duración del tratamiento fue de 28 días Md (r: 21-40 d). En los p con cultivos positivos para SARM-Co, la PCR inicial fue mayor (Md 76 vs 50 mg/L, p < 0,02), la normalización se produjo después (Md 14 días vs 7 días, p < 0,03) y la duración del tratamiento (Md 32 días vs 23, p < 0,004), así como la estancia hospitalaria (Md 9 días vs 7, p = 0,12) fueron más prolongados. En la evolución 1 p recayó y 3 tuvieron secuelas; en todos se aisló SARM-Co. Conclusión: SARM-Co fue la causa más frecuente de las IOA y se asoció con mayor valor de PCR al ingreso, normalización tardía, mayor duración del tratamiento, y complicaciones.

Neumonía necrosante adquirida en la comunidad causada por Staphylococcus aureus resistente a meticilina ST30-SCCmecIVc-Spat019-PVL positivo en San Antonio de Areco, Argentina / Community-acquired necrotizing pneumonia caused by methicillin-resistant Staphylococcus aureus ST30-SCCmecIVc-spat019-PVL positive in San Antonio de Areco, Argentina

Community-acquired methicillin-resistant Staphylococcus aureus is the first cause of skin and soft tissue infections, but can also produce severe diseases such as bacteremia, osteomyelitis and necrotizing pneumonia. Some S. aureus lineages have been described in cases of necrotizing pneumonia worldwide, usually in young, previously healthy patients. In this work, we describe a fatal case of necrotizing pneumonia due to community-acquired methicillin-resistant S. aureus clone ST30-SCCmecIVc-spat019-PVL positive in an immunocompetent adult patient.

Staphylococcus aureus resistente a meticilina adquirido en la comunidad es la primera causa de infecciones de piel y partes blandas, aunque también puede producir infecciones graves, como bacteriemia, osteomielitis y neumonía necrotizante. Algunos linajes de S. aureus se han asociado a casos de neumonía necrotizante en el mundo, generalmente en pacientes jóvenes previamente sanos. En este trabajo comunicamos un caso fatal de neumonía necrotizante causado por el clon de S. aureus resistente a meticilina adquirido en la comunidad ST30-SCCmecIVc-spat019-LPV positivo, en un paciente adulto inmunocompetente

Staphylococcus aureus nasal carriage among outpatients attending primary health care centers: a comparative study of two cities in Saudi Arabia and Egypt

Epidemiological and molecular data on community acquired methicillin resistant Staphylococcus aureus (CA-MRSA) are still scarce in both Egypt and Saudi Arabia. There is almost no data regarding methicillin resistant Staphylococcus aureus (MRSA) prevalence in both countries. This study was conducted to investigate the prevalence and molecular epidemiology of S. aureus and MRSA nasal carriage among outpatients attending primary health care centers in two big cities in both countries. A total of 206 nasal swabs were obtained, 103 swabs from each country. S. aureus isolates were characterized by antibiotic susceptibility, presence of mecA and PVL genes, SCCmec-typing and spa typing, the corresponding Multi locus sequence typing clonal complex was assigned for each spa type based on Ridom StaphType database. MRSA was detected in 32% of the Egyptian outpatients while it was found in 25% of the Saudi Arabian outpatients. All MRSA isolates belonged to SCCmec type V and IVa, where some isolates in Saudi Arabia remained nontypeable. Surprisingly PVL+ isolates were low in frequency: 15% of MRSA Egyptian isolates and 12% of MRSA isolates in Saudi Arabia. Two novel spa types were detected t11839 in Egypt, and t11841 in Saudi Arabia. We found 8 spa types among 20 isolates from Egypt, and 12 spa types out of 15 isolates from Saudi Arabia. Only two spa types t008 and t223 coexisted in both countries. Four clonal complexes (CC5, CC8, CC22, and CC80) were identified in both Egypt and Saudi Arabia. However, the data collected lacked a representation of isolates from different parts of each country as only one health center from each country was included, it still partially illustrates the CA-MRSA situation in both countries. In conclusion a set of control measures is required to prevent further increase in MRSA prevalence.

Infección por Staphyloccus aureus resistente a la meticillina adquirido en la comunidad (SAMR-AC) / Community-acquired methicillin-resistant Staphylococcus aureus infection (CA-MRSA)

Se presenta un paciente de 1 año de edad con antecedentes de salud, que desarrolló infección estafilocócica de piel y partes blandas, que lo llevó al desarrollo de shock tóxico, disfunción múltiple de órganos y muerte. Se aisló en cultivo de tejido pulmonar posmorten cepa de Staphylococcus aureus resistente a la meticillina, productor de la toxina Panton-Valantine leucocidina demostrado por caracterización molecular. Se estableció el diagnóstico anatomopatológico de sepsis generaliza y bronconeumonía necrosante bilateral.

A one-year old patient with history of health problems, who developed Staphylococcus aureus-caused infection in the skin and soft tissues that led him to toxic shock, multiple organ failure and death. Methilline-resistant Staphylococcus aureus strain was isolated in pulmonary tissue culture after death. This strain produced Panton-Valantine toxin called leukocidin as proved in molecular characterization. There was established the anatomic-pathological diagnosis of generalized sepsis and bilateral necrosing bronchopneumonia.

Embolia pulmonar séptica de origen cutáneo / Septic pulmonary embolism of cutaneous origin

La embolia pulmonar séptica es una enfermedad grave y poco frecuente que se caracteriza por presentar infiltrados pulmonares bilaterales asociados a un foco infeccioso extrapulmonar. Se relaciona principalmente a endocarditis derecha, tromboflebitis pelviana, accesos vasculares y menos frecuentemente a infecciones profundas como osteomielitis, artritis séptica o piomiositis. El Staphylococcus aureus meticilino-resistente adquirido en la comunidad (SAMR-AC) es un patógeno emergente, con alta virulencia y de rápida propagación, que afecta a sujetos sin enfermedades previas relacionadas o factores de riesgo conocidos. Causa infecciones de piel y partes blandas y con menor frecuencia infecciones graves como fascitis necrotizante, artritis séptica, osteomielitis, piomiositis y neumonía necrotizante. Su epidemiología, patogenia y manifestaciones clínicas difieren de las causadas por el SAMR adquirido en el hospital. Presentamos el caso de un varón de 67 años con embolias pulmonares sépticas causadas por SAMR-AC con origen en una infección cutánea.

Septic pulmonary embolism is a serious and rare illness characterized by pulmonary infiltrates associated with an extrapulmonary infectious focus. It is mainly related to right-sided endocarditis, pelvic thrombophlebitis, vascular access and less frequently to deep infections such as osteomyelitis, septic arthritis and pyomyositis. The community-acquired methicillin-resistant Staphylococcus aureus (MRSA) is an emerging pathogen with high virulence and rapid spread involving subjects without previous related diseases or known risk factors. It causes infections of skin and soft tissue and less frequently other serious infections such as necrotizing fascitits, septic arthritis, osteomyelitis, pyomyositis and necrotizing pneumonia. Epidemiologically, pathogenesis and clinical manifestations differ from those caused by MRSA acquired in the hospital. We present the case of a 67 year-old male with septic pulmonary embolism caused by community acquired MRSA that started with a skin infection.

Methicillin/Oxacillin-resistant Staphylococcus aureus as a hospital and public health threat in Brazil

Methicillin-resistant Staphylococcus aureus is an established nosocomial pathogen (HA-MRSA, hospital acquired MRSA), but has recently begun to appear in the community (CA-MRSA, community acquired MRSA). The cause of resistance to methicillin and all other â-lactam antibiotics is the mecA gene, which is situated on a mobile genetic element, the Staphylococcal Cassette Chromosome mec (SCCmec). Seven major variants of SCCmec, type I to VII are distinguished. HA-MRSA disseminated worldwide and causes the majority of S. aureus nosocomial infections with a limited number of clones disseminated including the Brazilian Epidemic Clone (BEC, ST239-MRSA-III). CA-MRSA isolates are susceptible to non-â-lactam antibiotics, usually isolated from healthy individuals which do not possess any unknown risk factors for MRSA infection and are associated with a larger clonal diversity compared with HA-MRSA. However, during recent years distinction between HA-MRSA and CA-MRSA is beginning to fade. Actually, knowledge about MRSA disseminating clones is required to implement any strategies to control the transmission of MRSA either within hospitals or in community. For this reason, rapid identification of strains is an important issue. The rate of HA-MRSA can be reduced substantially through the implementation of interventions strategies, even in settings where MRSA is endemic as in most Brazilian hospitals. However, these policies could be quite complicated in the light of an increasing CA-MRSA prevalence in healthcare facilities, considering that distinction between HA-MRSA and CA-MRSA has started to disappear.