A retrospective analysis of clinical characteristics and prognostic factors for 152 cases of Staphylococcus aureus bloodstream infection / 中华预防医学杂志

To understand the clinical characteristics of Staphylococcus aureus bloodstream infection and the main risk factors affecting clinical prognosis, providing a reference for clinical prevention and control of Staphylococcus aureus bloodstream infection. In this study, the clinical data of 152 patients with Staphylococcus aureus bloodstream infection admitted to Guangdong Provincial People's Hospital from January 2019 to December 2021 were retrospectively analyzed by reviewing the electronic medical record system, including underlying diseases, clinical characteristics, risk factors, and bacterial resistance. Statistical methods such as Chi-Squared Test and t Test were used to analyze the related risk factors that may affect the clinical characteristics and prognosis of patients with Staphylococcus aureus and methicillin-resistant Staphylococcus aureus (MRSA) bloodstream infection, then the variables with P<0.05 in univariate analysis were included in the multivariate logistic regression model to analyze the independent risk factors of poor prognosis. The results showed among 152 patients with Staphylococcus aureus bloodstream infection, 50 patients (32.89%) were infected with MRSA. In comparison, 102 patients (67.11%) were infected with methicillin-sensitive Staphylococcus aureus (MSSA). Except for rifampicin, the resistance rate of MRSA to commonly used antibiotics was all higher than that of MSSA, and the difference was statistically significant (Chi-square values were 8.272, 11.972, 4.998, 4.776, respectively;all P-values are less than 0.05). Strains resistant to vancomycin, linezolid, and quinupristin/dalfopristin were not found. In the MRSA group, indwelling catheter and drainage tube, carbapenems, and β-lactamase inhibitor treatment were significantly higher than the MSSA group. The difference was statistically significant (P<0.05). The incidence of poor prognosis of bloodstream infection in the MRSA group was higher than that in the MSSA group (34.00% vs 13.73%), and the difference was statistically significant (χ2=8.495, P<0.05). No independent risk factors associated with poor prognosis were found in the included patients with MRSA bloodstream infection.Multivariate Logistic regression model analysis showed that solid malignant tumors (OR=13.576, 95%CI: 3.352-54.977, P<0.05), mechanical ventilation (OR=7.468, 95%CI: 1.398-39.884, P<0.05) were the most important independent risk factors for poor prognosis in patients with Staphylococcus aureus bloodstream infection. In summary, the poor prognosis rate of MRSA bloodstream infection is higher than that of MSSA. The clinical evaluation of related risk factors should be strengthened, targeted prevention and control interventions should be taken to improve the prognosis of patients with Staphylococcus aureus bloodstream infection, and the use of antibiotics should be rational and standardized, to control bacterial infection and drug resistance effectively .

Prevalencia de portación nasal de Staphylococcus aureus sensible y resistente a la meticilina en candidatos a artroplastia total de cadera o rodilla / Prevalence of nasal carriage of methicillin-sensitive and methicillin-resistant Staphylococcus aureus in candidates for total hip or knee arthroplasty

INTRODUCIÓN Las infecciones perioperatorias en cirugía de reemplazo articular son fuente importante de morbimortalidad, así como de altos costos económicos y sociales, tanto para el paciente como para su entorno. La colonización preoperatoria por Staphylococcus aureus ha sido reconocida como un factor de riesgo importante para desarrollar una infección de sitio quirúrgico.El objetivo de este estudio es conocer la prevalencia de portación nasal de S. aureus, tanto sensible a la meticilina (SASM) como resistente a la meticilina (SARM), en pacientes candidatos a cirugía de reemplazo articular de cadera o rodilla. MATERIALES Y MÉTODOS Se realizó un estudio observacional de una cohorte retrospectiva de pacientes con indicación de artroplastia total de cadera (ATC) y rodilla (ATR) electiva por artrosis severa en un hospital público de Chile. Los pacientes fueron sometidos a tamizaje preoperatorio de portación, cultivándose muestras obtenidas mediante hisopado de ambas fosas nasales. Los datos del laboratorio fueron recopilados y presentados como porcentaje de portación de S. aureus. RESULTADOS Se estudiaron 303 pacientes consecutivos de ATC y 343 de ATR. En total, 483 de los 646 pacientes (74,7%) tuvieron estudio preoperatorio de portación nasal. Se identificaron 123 pacientes (25,4%) portadores de S. aureus, de los cuales sólo 2 (0,41%) casos correspondieron a SARM. CONCLUSIÓN La prevalencia de portación nasal de S. aureus obtenida fue de 25%, similar a lo reportado en otras series. La prevalencia de SARM (0.41%), sin embargo, estuvo bajo lo descrito en la literatura internacional (0,6­6%). Sería de utilidad, dada la alta prevalencia de portación descrita en nuestro trabajo y de acuerdo a evidencia publicada recientemente, realizar protocolos de descolonización universales, sin necesidad de realizar tamizaje preoperatorio.

INTRODUCTION Surgical-site infections in joint replacement surgery are an important source of morbidity and mortality that entail high economic and social burden both for the patient and their environment. Preoperative colonization by Staphylococcus aureus has been recognized as an important risk factor for the development of surgical-site infection. The aim of the present study is to determine the prevalence of nasal colonization by S. aureus, both methicillin-sensitive (MSSA) and methicillin-resistant (MRSA) in patients who are candidates for total replacement of the hip or knee joints. MATERIALS AND METHODS A retrospective observational study of a cohort of 646 patients with an indication to undergo total hip arthroplasty (THA) or total knee arthroplasty (TKA) due to severe osteoarthritis was performed in a Public Hospital in Chile. The patients were submitted to a preoperative screening for S. aureus carriage, and the culture samples were obtained by swabbing both nostrils. The laboratory data was collected and presented as a percentage of carriage. RESULTS We consecutively examined 303 THA and 343 TKA patients. A total of 483 of the 646 patients (74.7%) underwent a preoperative study of nasal carriage. We identified 123 (25.4%) S. aureus carriers, and only found 2 (0.41%) cases corresponding to MRSA. CONCLUSION We found a prevalence of nasal carriage of S. aureus of 25.4%, a rate similar to that reported in other series. The prevalence of MRSA (0.41%), however, was lower than that reported in the international literature (0.6­6%). Given the high prevalence of carriage described in our work and according to recently published data, it would be worthwhile to carry out universal decolonization protocols, without the need for preoperative screening.

Vancomycin resistance among methicillin resistant Staphylococcus aureus isolates from intensive care units of tertiary care hospitals in Hyderabad.

Background & objectives: Multidrug resistant methicillin-resistant Staphylococcus aureus (MRSA) is a major cause of nosocomial and community acquired infections and is on the rise. The glycopeptide vancomycin has been proposed as the drug of choice for treating such infections. The present study aimed at identifying the vancomycin resistance both phenotypically and genotypically among the MRSA isolates from two tertiary care hospitals in Hyderabad, south India. Methods: MRSA were isolated and identified from different clinical samples collected from ICUs of tertiary care hospitals in Hyderabad using conventional methods. Antibiogram of the isolates and vancomycin MIC were determined following CLSI guidelines. vanA was amplified by PCR using standard primers. Results: All vancomycin resistant S. aureus (VRSA) isolates were MRSA. The VRSA isolates were positive for vanA gene, except one which was negative. All VRSA had a vancomycin MIC in the range of 16-64 mg/l. Interpretation & conclusions: The increase in vancomycin resistance among MRSA and excessive use of antimicrobial agents have worsened the sensitivity. Larger studies need to be done in various geographical regions of the country to better define the epidemiology, mechanism of vancomycin resistance in S. aureus and its clinical implications.

Reporte de caso: estafilococcemia / Staphyloccemia: case report

El término estafilococo (s.) deriva de la expresión griega STAPHYLE (racimos de uva,) y refleja su disposción microscópica característica en grupos. El S. Aureus es un microorganismo gram positivo, caracterizado por cocos con un di metro de 0.7-1.2 um. (10). Presentamos un caso de estafilococcemia generada en piel, que reunía criterios de shock tóxico en un paciente masculino no inmunocomprometido

Control de infecciones por Staphylococcus aureus resistente a meticilina en una unidad de neonatología / Control of methicillin-resistant Staphylococcus aureus at a neonatal ward

Durante 4 meses de 1988, en la Unidad de Neonatología del Hospital San Juan de Dios, se realizó un proyecto de control de Staphylococus aureus meticilina-resistente, y se compararon tasas de incidencia y tipo de infecciones en relación a un período anterior de 4 meses. Las medidas de control del brote epidémico incluyeron: información y motivación del personal especialmente en relación a técnica de lavado de manos y aislamiento, ordenamiento del ingreso y flujo de circulación de los niños en la unidad, aplicación de técnicas de aislamiento estricto en colonizados e infectados, control microbiológico de los recién nacidos, personal y ambiente; y erradicación del agente etiológico con antibióticos tópicos y orales. En este período de cuatro meses, en comparación a los 4 meses anteriores, disminuyó significativamente la tasa de colonización e infección debida a Staphylococcus aureus resistente a meticilina de 30,7 a 16% y de 12,6 a 6,8%, respectivamente. Con esta medida de control de infección intrahospitalaria realizada simultáneamente, fue posible disminuir en forma significativa la colonización e infección por Staphylococcus aureus resistente a meticilina

Drug resistance pattern of methicillin resistant Staphylococcus aureus.

A total of 404 methicillin resistant Staphylococcus aureus (MRSA) isolated from pus, CSF, blood and sputum of various hospitalized cases were analyzed. The resistance pattern of these strains were gentamicin (51.8%), erythromycin (80.1%) and co-trimoxazole (89.6%). All these strains were sensitive to vancomycin. The isolation rate was maximum from various surgical specialties (General surgery-28.5%; Neurosurgery-16.3% and Cardio-thoracic unit-10.5%) followed by Children Ward, Premature Nursery and Gynecology Ward, respectively. Use of cloxacillin needs to be restricted since vancomycin, the drug of choice is not available in our country.

Efectividad de los antibióticos fosfocina y la combinación celbenin y estreptomicina como profilácticos en la cirugía vascular / Effectiveness of fosfocin and combined celbenin and streptomycin as prophylactic antibiotics in vascular surgery

Se estudió la efectividad como profilácticos de los antibióticos fosfocina y la combinación celbenin y estreptomocina en 40 pacientes que fueron sometidos a algún tipo de cirugía vascular. No fue posible llegar a conclusiones definitivas, ya que la muestra obtenida, por su tamaño, no mostraba diferencias estadisticamente significativas, pero no hubo en ninguno de los regimenes evaluados signos de endocarditis bacterianas ni infección precoz de la prótesis vascular. Los gérmenes más frecuentemente aislados fueron grampositivos, y el único hemocultivo positivo hallado fue de Escherichia coli en un paciente diabético que evolucionó satisfactoriamente a pesar del cuadro febril que presentó