Escarlatina estafilocócica como complicación de quemadura por contacto

El Staphylococcus aureus causa una variedad de infecciones localizadas e invasivas supurativas y 3 síndromes mediados por toxinas: Síndrome de choque tóxico estafilocócico (STSS, por sus siglas en ingles), síndrome de piel escaldada estafilocócica (SSSS) e intoxicación alimentaria1. La escarlatina estafilocócica está relacionada con las toxinas del STSS y SSSS. De hecho, se pudieron describir dos síndromes diferentes cada uno relacionado a un tipo de toxina que eran formas atenuadas de estas entidades. El curso de esta patología generalmente es autolimitado, pero puede evolucionar rápidamente a enfermedad severa que ponga en peligro la vida. Un entendimiento de este conjunto de patologías nos permite abordar al paciente de una manera oportuna, manteniendo la vigilancia y en caso de ser necesario intervenir para evitar el advenimiento del STSS que puede desembocar en falla orgánica múltiple e incluso la muerte. Esta revisión se trata de un caso atendido en la unidad de quemados del Hospital del Niño Dr. José Renán Esquivel (HDNJRE) en el mes de mayo del 2023 con quemadura por contacto complicada con escarlatina estafilocócica. (provisto por Infomedic International)

Staphylococcus aureus causes a variety of localized and invasive suppurative infections and 3 toxin-mediated syndromes: staphylococcal toxic shock syndrome (STSS), staphylococcal scalded skin syndrome (SSSS) and food poisoning1 . Staphylococcal scarlet fever is related to STSS and SSSS toxins. In fact, two different syndromes each related to a type of toxin could be described which were attenuated forms of these entities. The course of this pathology is usually self-limiting, but can rapidly progress to severe life-threatening disease. An understanding of this set of pathologies allows us to approach the patient in a timely manner, maintaining vigilance and if necessary intervening to prevent the advent of STSS that can lead to multiple organ failure and even death. This review is about a case treated at the burn unit of the Hospital del Niño Dr. José Renán Esquivel (HDNJRE) in May 2023 with contact burn complicated by staphylococcal scarlet fever. (provided by Infomedic International)

Prevalencia de Staphylococcus aureusy su sensibilidad antibiótica en aislamientos en infecciones de piel y partes blandas en pacientes ambulatorios / Staphylococcus aureus prevalence and antimicrobial susceptibility in isolates from skin and soft tissue infections in outpatients

ntroducción: Las infecciones de piel y partes blandas (IPPB) constituyen la tercera causa de consulta en nuestro centro. S.aureus es el agente etiológico más frecuente en este tipo de infecciones y la meticilino resistencia es clínicamente el mecanismo de resistencia más importante. El objetivo de este trabajo fue analizar la prevalencia de los distintos agentes etiológicos en IPPB en pacientes ambulatorios, así como también estudiar su sensibilidad a los antibióticos y resistencias acompañantes más frecuentes. Materiales y métodos: Estudio descriptivo y retrospectivo que incluyó todas las muestras provenientes de IPPB de pacientes ambulatorios desde octubre de 2017 a abril de 2022. Resultados: Se obtuvieron 180 cultivos positivos de muestras provenientes de IPPB durante el periodo estudiado, 12 fueron infecciones polimicrobianas. En total se obtuvieron 307 aislamientos: el microorganismo aislado con mayor frecuencia fue S.aureus (111; 36,2%). Se hallaron 71 SAMR (64%) y 40 SAMS (36%). De los SAMR, 67 (95%) fueron comunitarios (SAMRC) por criterios microbiológicos, y 4 SAMR hospitalarios (5%). De las cepas SAMRC, 44 (66%) no presentaron resistencias acompañantes, 15 (22% ) fueron resistentes a eritromicina, 12 (18%) a gentamicina y 7 (10%) a clindamicina. Conclusiones: El microorganismo más frecuentemente aislado en IPPB en pacientes ambulatorios fue el S.aureus y 67 aislamientos fueron categorizados como SAMRC por lo cual es necesario considerar al SAMRC como un patógeno frecuente. Debido a la baja resistencia hallada para CLI y TMS ambos podrían ser de elección en el tratamiento empírico en las IPPB en pacientes ambulatorios

Background:S. aureus is the main cause of skin and soft tissues infections (SSTIs) in immunocompetent patients. This type of infection is the third cause of medical consultation in our center. Our objective was to evaluate the prevalence of S. aureus, as well as its sensitivity to antimicrobials, isolated from skin and soft tissue samples from outpatients at an interzonal general acute care hospital located in Buenos Aires, Argentina.Methods: Descriptive and retrospective study that included all outpatient SSTIs samples from October 2017 to April 2022.Results: We obtained 215 positive cultures of samples from SSTIs during the study period. Of a total of 276 isolates: the most frequently isolated microorganism wasS. aureus (111; 40.22%). The prevalence of S. aureuswas 51.63%. We found 71 MRSA (63.96%). Of the SAMR strains, 60.56% did not present accompanying resistance, and only 8 isolates (11.27%) showed resistance to clindamycin. All SAMRs remained sensitive to minocycline and trimethoprim-sulfamethoxazole.Conclusions: The most frequently isolated microorganism in SSTIs was S. aureus and 71 isolates were categorized as SAMR, therefore it is necessary to consider SAMR as a frequent pathogen. Due to the low resistance found for CLI and TMS, they should be considered for empirical treatment in SSTIs in outpatients

Bactericidal Effect of Selenium Nanoparticles Combined with Povidone-iodine on Pathogenic Bacteria in Surgical Site Infection / 中山大学学报(医学科学版)

ObjectiveTo investigate the bactericidal effect of loaded multifunctional povidoneiodine-nanometer selenium （PVP-I@Se） disinfectant on Staphylococcus aureus （SA） and methicillin-resistant Staphylococcus aureus （MRSA）， and to provide an experimental basis for the reduction of surgical site infection （SSI）. MethodsThe control group was the povidone iodine （PVP-I） group with different concentrations of iodine （50， 75， 100， 200 and 400 μg/mL）. The PVP-I@Se group （experimental group） was the PVP-I group further supplemented with 2 μg/mL Selenium nanoparticles （SeNPs）. Then we compared the bactericidal effect of the two groups of disinfectant solutions on SA and MRSA by examining the minimum inhibitory concentration （MIC）， minimum bactericidal concentration （MBC）， the shortest sterilization time at a concentration of 50 μg/mL iodine and the inhibition zone diameters at concentrations of 200 μg/mL and 400 μg/mL iodine. ResultsMIC values of PVP-I against SA and MRSA were both 79.17 μg/mL， and those of PVP-I@Se were 54.17 and 70.83 μg/mL， respectively. MBC values of PVP-I against SA and MRSA were 129.17 and 150.00 μg/mL， respectively， and those of PVP-I@Se were 70.83 and 87.50 μg/mL， respectively. At a concentration of 50 μg/mL iodine， the shortest sterilization time of PVP-I for SA and MRSA was 130 s and 140 s， respectively， and that of PVP-I@Se was 65 s and 75 s， respectively. At a concentration of 200 μg/ml iodine， the inhibition zone diameters of PVP-I for SA and MRSA were 7.67 mm and 8.33 mm， and those of PVP-I@Se were both 9.50 mm. At a concentration of 400 μg/mL iodine， the inhibition zone diameters of PVP-I for SA and MRSA were 9.00 mm and 9.33 mm， and those of PVP-I@Se were 11.67 mm and 12.00 mm， respectively. ConclusionsPVP-I with different concentrations of 50， 75， 100， 200 and 400 μg/mL iodine supplemented with 2 μg/mL SeNPs have better and faster bactericidal effect on SA and MRSA. When combined with SeNPs， PVP-I can enhance the bactericidal activity against SA and MRSA， but with better sensitizing effect on SA than MRSA and higher demand of iodine concentration （400 μg/mL） for sensitizing effect on MRSA. This study provides a theoretical basis for selecting optimal concentration and action time of the disinfectant， thus reducing SSI.

Piomiositis multifocal por Staphylococcus aureus. A propósito de un caso pediátrico

Introducción: la piomiositis (PMS) es una infección bacteriana aguda o subaguda del músculo esquelético. Entidad rara en pediatría, suele acompañarse de la formación de abscesos. Se presenta más frecuentemente en preescolares de sexo masculino, afectando mayoritariamente a extremidades y región pélvica. La manifestación multifocal es frecuente. El principal agente etiológico es Staphylococcus aureus. Caso clínico: 3 años, sexo masculino, sano. Consulta por fiebre continua de hasta 39 ºC de seis días de evolución, dolor de ambos miembros inferiores a predominio izquierdo, cojera y repercusión general. Examen físico: tumoración en muslo izquierdo de límites difusos de 13 x 5 cm, lisa, firme, impresiona adherida a planos musculares, dolorosa. Sin elementos fluxivos en la piel. Ecografía de partes blandas: aumento de tejidos blandos de la extremidad. Resonancia magnética (RM): abscesos que comprometen logia de los aductores del miembro izquierdo, el vasto externo del muslo derecho, musculatura paravertebral lumbar izquierda y cérvico-torácica izquierda. Tratamiento: drenaje, requiere de múltiples limpiezas quirúrgicas y antibioticoterapia prolongada. Cultivo de la lesión: Staphylococcus aureus meticilino resistente (SAMR). Buena evolución clínica e imagenológica. Discusión: la PMS ha presentado una incidencia creciente con la aparición del SAMR. La ecografía es un método adecuado para realizar diagnóstico local. La experiencia en la interpretación de la RM permite pesquisar el compromiso multifocal, identificando focos sin traducción clínica. La antibioticoterapia y el drenaje quirúrgico son los pilares del tratamiento. El pronóstico es bueno en la mayoría de los casos.

Summary: Introduction: pyomyositis (PMS) is an acute or subacute bacterial infection of the skeletal muscle. It is a rare infection in pediatrics, and it is usually accompanied by abscess formation. It occurs more frequently in male preschoolers, mostly affecting the extremities and pelvic region. The multifocal manifestation is frequent. The main etiological agent is Staphylococcus aureus. Clinical case: 3 year-old, male, healthy patient. He consulted for continuous fever of up to 39ºC of 6 days of evolution, pain in both lower limbs predominantly on the left, lameness and general repercussions. Physical examination: a 13 x 5 cm tumor in the left thigh with diffuse limits, smooth, firm, adhered to muscle layers, painful. Without fluxive elements on the skin. Soft tissue ultrasound: enlargement of the soft tissues of the extremity. Magnetic resonance imaging (MRI): abscesses involving the adductor lodge of the left limb, the vastus lateralis of the right thigh, left lumbar paravertebral musculature and left cervical-thoracic musculature. Treatment: drainage, requires multiple surgical cleanings and prolonged antibiotic therapy. Culture of the lesion: methicillin-resistant Staphylococcus Aureus (MRSA). Good clinical and imaging evolution. Discussion: PMS has had an increasing incidence with the appearance of MRSA. Ultrasound is a suitable method for local diagnosis. Experience in the interpretation of MRI has enabled us to research multifocal involvement, identifying unobserved foci during clinical check-up. Antibiotic therapy and surgical drainage are the main treatments. The prognosis is good in most cases.

Introdução: Ia Piomiosite (TPM) é uma infecção bacteriana aguda ou subaguda do músculo esquelético. É uma entidade rara em pediatria, costuma vir acompanhada de formação de abscessos. Ocorre com maior frequência em pré-escolares do sexo masculino, afetando principalmente as extremidades e a região pélvica. A manifestação multifocal é comum. O principal agente etiológico é o Staphylococcus aureus. Caso clínico: paciente 3 anos, sexo masculino, hígido. Consulta por febre contínua de até 39ºC há 6 dias, dor em ambos os membros inferiores predominantemente esquerdo, claudicação e repercussão geral. Exame físico: tumor na coxa esquerda com limites difusos de 13 x 5 cm, liso, firme, aparentemente aderido aos planos musculares, doloroso. Sem elementos fluidos na pele. Ultrassonografia de tecidos moles: aumento dos tecidos moles da extremidade. Ressonância magnética (RM): abscessos envolvendo o alojamento adutor do membro esquerdo, vasto lateral da coxa direita, músculos paravertebrais lombares esquerdos e cérvico-torácicos esquerdos. Tratamento: drenagem, requer múltiplas limpezas cirúrgicas e antibioticoterapia prolongada. Cultura da lesão: Staphylococcus aureus resistente à meticilina (MRSA). Boa evolução clínica e imagiológica. Discussão: a TPM tem tido uma incidência crescente com o aparecimento do MRSA. A ultrassonografia é um método adequado para diagnóstico local. A experiência na interpretação de ressonância magnética permite-nos investigar o envolvimento multifocal, identificando focos sem tradução clínica. A antibioticoterapia e a drenagem cirúrgica são os pilares do tratamento. O prognóstico é bom na maioria dos casos.

Bacteriological characteristics of primary breast abscesses in patients from the community in the era of microbial resistance

Abstract Objective: The aim of this study is to evaluate the etiological profile and antimicrobial resistance in breast abscess cultures from patients from the community, treated at a public hospital located in Porto Alegre, Brazil. Methods: This is an retrospective cross-sectional study that evaluated the medical records of patients with bacterial isolates in breast abscess secretion cultures and their antibiograms, from January 2010 to August 2022. Results: Based on 129 positive cultures from women from the community diagnosed with breast abscesses and treated at Fêmina Hospital, 99 (76.7%) of the patients had positive cultures for Staphylococcus sp, 91 (92%) of which were cases of Staphylococcus aureus. Regarding the resistance profile of S. aureus, 32% of the strains were resistant to clindamycin, 26% to oxacillin and 5% to trimethoprim-sulfamethoxazole. The antimicrobials vancomycin, linezolid and tigecycline did not show resistance for S. aureus. Conclusion: Staphylococcus aureus was the most common pathogen found in the breast abscess isolates during the study period. Oxacillin remains a good option for hospitalized patients. The use of sulfamethoxazole plus trimethoprim should be considered as a good option for use at home, due to its low bacterial resistance, effectiveness and low cost.

Detección de Staphylococcus aureus en teléfonos móviles de estudiantes de último año de odontología / Detection of Staphylococcus aureus in mobile phones of final year dental students

Objetivo: El propósito de este estudio fue detectar la incidencia de Staphylococcus aureus (S. aureus) en pantallas de teléfonos móviles de estudiantes de último año de odontología mediante técnicas microbiológicas. Métodos: Estudio observacional de tipo transversal descriptivo. Se tomaron 92 muestras de pantallas de teléfonos móviles, se realizó la identificación de S. aureus mediante pruebas microbiológicas: fermentación del manitol, reacciones positivas a las pruebas de desoxirribonucleasa, catalasa y coagulasa. Resultados: Se aisló 16 cepas de S. aureus 16/92 (17,4%) en pantallas de teléfonos móviles. El 100% de las cepas aisladas dieron reacciones positivas a las pruebas de desoxirribonucleasa, catalasa y coagulasa. Conclusiones: Se evidencia la presencia de S. aureus en pantallas de celulares de los teléfonos móviles de los estudiantes de último año lo que representa un riesgo para la diseminación de este patógeno.

Objective: The purpose of this study was to detect the incidence of S. aureus on mobile phone screens of last-year dental students using microbiological techniques. Methodology: Descriptive cross-sectional observational study. 92 samples were taken from mobile phone screens, S. aureus was identified by microbiological tests: mannitol fermentation, positive reactions to deoxyribonuclease, catalase and coagulase tests. Results: 16 strains of S. aureus 16/92 (17.4%) were isolated on mobile phone screens. 100% of the strains emerged positive reactions to deoxyribonuclease, catalase and coagulase tests. Conclusions: The presence of S. aureus is evidenced in cell phone screens of senior students' mobile phones, which represents a risk for the spread of this pathogen.

Aceite esencial de Arazá (Eugenia stipitata McVaugh) con actividad antibacteriana

Introducción: El Perú es uno de los países con mayor biodiversidad en especies botánicas, algunas con propiedades medicinales conocidas. Objetivo: Determinar el efecto antibacteriano del aceite esencial de las hojas de Eugenia stipitata McVaugh frente a Staphylococcus aureus ATCC 25923, Escherichia coli ATCC 25922 y Salmonella enterica sv Enteritidis ATCC 13076. Métodos: Estudio de tipo básico con enfoque cuantitativo y experimental. Las plantas provienen del distrito de Belén, ciudad de Iquitos, Departamento de Loreto. La técnica para la extracción del aceite esencial fue la de arrastre de vapor y la técnica microbiológica para determinar el efecto antimicrobiano la de Kirby Bauer. Se trabajaron las muestras en 4 concentraciones 100, 75, 50 y un 25 %; un control negativo solo con dimetilsulfóxido, se utilizaron 5 repeticiones por cada muestra. Resultados: La muestra a concentración al 100 % tuvo actividad antibacteriana contra Staphylococcus aureus. La actividad del ensayo frente a Escherichia coli demostró ser efectiva en todas las muestras, sin embargo, se observó que los halos de inhibición de mayor diámetro se manifestaron en las muestras al 100 % y 75 %. Además, se evidenció actividad antibacteriana a concentraciones del 100 %, 75 % y un 50 % frente a Salmonella enterica sv Enteritidis. Conclusiones: El aceite esencial de las hojas de Eugenia stipitata McVaugh presenta efecto antibacteriano frente a Staphylococcus aureus, Escherichia coli y Salmonella enterica sv Enteritidis.

Introduction: Peru is one of the countries with the greatest biodiversity in botanical species, some with known medicinal properties. Objective: To determine the antibacterial effect of the essential oil of Eugenia stipitata McVaugh leaves against Staphylococcus aureus ATCC 25923, Escherichia coli ATCC 25922 and Salmonella enterica sv Enteritidis ATCC 13076. Methods: Basic study with a quantitative and experimental approach. Plants came from the district of Belén, city of Iquitos, Department of Loreto. The technique for the extraction of the essential oil was steam dragging and the microbiological technique to determine the antimicrobial effect was Kirby Bauer's technique. The samples were worked in 4 concentrations 100, 75, 50 and 25 % and a negative control only with dimethyl sulfoxide, using 5 replicates for each sample. Results: The sample at 100 % concentration had antibacterial activity against Staphylococcus aureus. The activity of the assay against Escherichia coli proved to be effective in all the samples, however, it was observed that the inhibition halos of greater diameter were manifested in the samples at 100 % and 75 %. In addition, antibacterial activity was evidenced at concentrations of 100 %, 75 % and 50 % against Salmonella enterica sv Enteritidis. Conclusions: The essential oil of Eugenia stipitata McVaugh leaves has an antibacterial effect against Staphylococcus aureus, Escherichia coli and Salmonella enterica sv Enteritidis.

Endocarditis Infecciosa Mural Apical del Ventrículo Izquierdo: Presentación de caso clínico y revisión bibliográfica / Infectious Apical Mural Endocarditis of the Left Ventricle: Clinical case presentation and bibliographic review

RESUMEN La endocarditis mural es una forma infrecuente de infección intracardiaca que afecta al endocardio no valvular que pue- de presentarse con complicaciones similares a la endocarditis infecciosa valvular. Se recomienda la ecocardiografía para confirmar el diagnóstico cuando exista un alto índice de sospecha. Con respecto al tratamiento, existe evidencia limitada acerca de las estrategias terapéuticas en la endocarditis mural, sin embargo en la mayoría de casos reportados se recomienda iniciar antibioticoterapia dirigida asociado a una intervención quirúrgica precoz. A continuación, se presenta un caso clínico de un paciente masculino de 74 años con fenómenos embólicos sistémicos, en quien se documenta por ecocardiograma transesofágico una endocarditis mural en ápex del ventrículo izquierdo asociado a una bacteriemia por Staphylococcus aureus. Este caso pone de manifiesto la importancia de una valoración ecocardiográfica detallada de las válvulas y cámaras cardíacas ante la sospecha de una endocarditis infecciosa.

ABSTRACT Mural endocarditis is an uncommon form of intracardiac infection affecting the non valvular endocardium that can present with complications similar to valvular infective endocarditis. Echocardiography is recommended to confirm the diagnosis when there is a high index of suspicion. Regarding treatment, there is limited evidence about therapeutic strategies in mural endocarditis, however in most reported cases it is recommended to initiate targeted antibiotic therapy associated with early surgical intervention. The following is a clinical case of a 74-year-old male patient with systemic embolic phenomena, in whom a transesophageal echocardiogram documented mural endocarditis in the apex of the left ventricle associated with Staphylococcus aureus bacteremia. This case highlights the importance of a detailed echocardiographic assessment of the cardiac valves and chambers when infective endocarditis is suspected.

Celulitis facial por Staphylococcus aureus con metástasis infecciosas y evolución tórpida. Caso pediátrico / Facial cellulitis due to Staphylococcus aureus with metastatic infection and torpid course. A pediatric case report

La bacteriemia por Staphylococcus aureus se define como el aislamiento de dicho germen en al menos un cultivo de sangre. Las metástasis infecciosas se originan por diseminación hematógena y su posterior localización en un sitio distinto al órgano en donde se originó el proceso infeccioso. La prevalencia en la presentación de estos focos infecciosos secundarios es baja en la edad pediátrica, por lo que representa un desafío diagnóstico. Se presenta el caso de un paciente pediátrico con una celulitis facial por Staphylococcus aureus, con metástasis infecciosas y evolución tórpida.

Bacteremia due to Staphylococcus aureus is defined as the isolation of this microorganism in at least one blood culture. A metastatic infection is caused by the hematogenous dissemination and subsequent location of the microorganism in a site other than the one where the infection started. The prevalence of these secondary sources of infection is low in the pediatric population, which is a diagnostic challenge. Here we describe the case of a pediatric patient with facial cellulitis due to Staphylococcus aureus, with metastatic infection and torpid course.

Osteomielitis primaria de esternón / Primary sternal osteomyelitis

La osteomielitis primaria de esternón es muy infrecuente en niños, con menos de 100 casos publicados hasta la actualidad. Su presentación clínica es a menudo inespecífica, lo que causa un retraso en el diagnóstico. Se presentan dos nuevos casos de osteomielitis primaria de esternón. Ambos referían un cuadro de fiebre, malestar general, dolor torácico y rechazo del decúbito, con eritema preesternal en uno de los casos. La velocidad de sedimentación globular y la proteína C-reactiva estaban elevadas en ambos casos. El diagnóstico se confirmó mediante estudios de imagen y en un caso se aisló Staphylococcus aureus sensible a meticilina en el hemocultivo. Ambos se recuperaron sin complicaciones con tratamiento antibiótico. Debe tenerse en cuenta la osteomielitis primaria de esternón en el diagnóstico diferencial del dolor torácico, especialmente si se acompaña de fiebre, signos inflamatorios locales, intolerancia al decúbito o elevación de reactantes de fase aguda.

Primary sternal osteomyelitis is very rare in children, with less than 100 cases published to date. Its clinical presentation is often non-specific, which results in a diagnostic delay. Here we describe 2 new cases of primary sternal osteomyelitis. Both referred fever, malaise, chest pain, and refusal to lie down, with pre-sternal erythema in one of the cases. The erythrocyte sedimentation rate and C-reactive protein values were high in both cases. The diagnosis was confirmed by imaging studies; methicillin-sensitive Staphylococcus aureus was isolated in the blood culture of one of them. Both recovered without complications with antibiotic treatment. Primary sternal osteomyelitis should be considered in the differential diagnosis of chest pain, especially if accompanied by fever, local inflammatory signs, intolerance to lying down, or increased acute phase reactants.

Síndrome de compresión medular de etiología infecciosa

El síndrome de compresión medular es una urgencia neuroquirúrgica debido a que un diagnóstico precoz y un tratamiento temprano podría revertir las incapacitantes secuelas ocasionadas por esta enfermedad. Las causas de este síndrome pueden ser traumática, metastásica, infecciosa y vascular (hematomas). La etiología infecciosa no es frecuente y el principal germen involucrado suele ser Staphylococcus aureus. A continuación presentamos el caso de una paciente de 58 años con síndrome de compresión medular de etiología infecciosa quien fue ingresada en el Servicio de Clínica Médica del Centro Médico Nacional.

Spinal cord compression syndrome is a neurosurgical emergency because early diagnosis and early treatment could reverse the disabling consequences caused by this disease. The causes of this syndrome can be traumatic, metastatic, infectious, and vascular (hematomas). Infectious etiology is not frequent and the main germ involved is usually Staphylococcus aureus. Below we present the case of a 58-year-old patient with spinal cord compression syndrome of infectious etiology who was admitted to the Medical Clinic Service of the National Medical Center.

Molecular Detection of Enterotoxigenic Staphylococcus aureus in Ready-to-eat Cowhide (‘Ponmo’) Collected from Lagos Metropolis, Nigeria

Aims: Ready-to-eat [RTE] animal products like ponmo are preferred by consumers due to its palatability and quality. However, foodborne pathogens particularly Staphylococcus aureus are sources of concern due to cross-contamination of raw and cooked cowhide. This study aimed to investigate the incidence of enterotoxigenic S. aureus in ready-to-eat locally processed cowhide. Methodology: Sixty (60) RTE cowhide samples were collected from different locations in Lagos, Nigeria and analyzed using conventional microbiological and molecular techniques for the detection of toxigenic S. aureus contamination. Suspected S. aureus isolates were confirmed by the presence of thermostable endonuclease [nuc] gene in their genome. Results: Result showed that 25 (41.67%) and 20 (33.50%) samples harbored coagulase-positive S. aureus and 20 other bacterial species different from S. aureus, respectively while 15 (24.83%) of the tested ponmo samples yielded no bacterial growth. Thirteen of the 15 randomly selected from the 25 suspected isolates were confirmed as S. aureus by the presence of thermostable endonuclease [nuc] gene in their genome. Enterotoxigenic genes were confirmed in all the 13 PCR detected S. aureus. Enterotoxin B gene is most prevalent in ponmo. Multiplex PCR detection of S. aureus enterotoxins [SE] genes revealed the molecular detection of different isolates carrying staphylococcal enterotoxin types A and B, mixed strain carrying both staphylococcal enterotoxins type A and type D. Antibiotic susceptibility of 20 S. aureus isolates revealed varying degrees of susceptibility patterns against the antimicrobial agents. Generally, gentamicin 70% (14/20), azithromycin 75% (15/20), co-trimoxazole 85% (17/20), levofloxacin 95% (19/20) were the most effective antibiotics to S. aureus. A low, ?50% susceptibility was recorded to chloramphenicol 55% (11/20) and nitrofurantoin 65% (13/20). A higher resistance to streptomycin (90%; 18/20) and ceftazidime (95%; 19/20) was identified, with resistance to ceftazidime being the highest (95%; 19/20). Conclusion: It can be concluded that RTE ponmo vended in the study sites is of low hygienic quality and may be of health risk to consumers. High level hygiene practice and good manufacturing practices are required during the production, distribution and marketing of ponmo to curb the potential health consequences of eating ponmo.

Neumonía por Pasteurella multocida y Staphylococcus aureus en una paciente sin patología subyacente / Pneumonia by Pasteurella multocida and Staphylococcus aureus in a patient whithout underlying conditions / Pneumonia por Pasteurella multocida e Staphylococcus aureus em uma paciente sem patologia subjacente

Resumen Muchos microorganismos capaces de producir infecciones en el ser humano son de origen zoonótico. Entre éstos está Pasteurella multocida, la cual se encuentra como comensal y/o patógeno oportunista, colonizando el tracto gastrointestinal y respiratorio de gran cantidad de mamíferos y aves. Por otro lado, Staphylococcus aureus es un colonizante de piel y nasofaringe y un patógeno oportunista para seres humanos y animales y su transmisión podría ser bidireccional. Se presenta un caso de neumonía por P. multocida y S. aureus en una mujer sin enfermedad subyacente, que acogía perros y gatos abandonados e ingresó con politraumatismo por caída desde un quinto piso. Ambos microorganismos fueron recuperados en una muestra de aspirado traqueal e identificados por Vitek®2 Compact. La identificación de P. multocida fue confirmada por espectrometría de masas (MALDI-TOF-MS) y presentó sensibilidad a penicilina, cefotaxima, amoxicilina-ácido clavulánico, ciprofloxacina, tetraciclina y trimetoprima-sulfametoxazol. S. aureus era sensible a meticilina sin resistencia acompañante.

Abstract Many microorganisms capable of producing infections in humans are of zoonotic origin. Among them, Pasteurella multocida, is a commensal and/or opportunistic pathogen that colonises the gastrointestinal and the respiratory tract of a great number of mammals and birds. On the other hand, Staphylococcus aureus is a coloniser of skin and nasopharynx and an opportunistic pathogen in humans and animals, whose transmission might be bidirectional. A case of pneumonia by P. multocida and S. aureus was presented in a woman without an underlying condition, who sheltered stray dogs and cats and was admitted with multiple trauma due to a fall from a fifth floor. Both microorganisms were recovered from a tracheal aspirate sample and identified by Vitek®2 Compact. Identification of P. multocida was confirmed by mass spectrometry (MALDI-TOF MS) and was susceptible to penicillin, cefotaxime, amoxicillin-clavulanic acid, ciprofloxacin, tetracycline and trimethoprim-sulfamethoxazole. S. aureus was methicillin-susceptible without accompanying resistance.

Resumo Muitos dos microrganismos capazes de produzir infecções no ser humano têm origem zoonótico. Entre eles está a Pasteurella multocida, que se encontra como comensal e/ou patógeno oportunista, colonizando o trato gastrintestinal e respiratório de grande quantidade de mamíferos e aves. Por outro lado, Staphylococcus aureus é um colonizador de pele e nasofaringe e um patógeno oportunista para seres humanos e animais e sua transmissão poderia ser bidirecional. Apresenta-se um caso de pneumonia por P. multocida e S. aureus em uma mulher, sem doença subjacente, que abrigava cães e gatos abandonados e entrou com múltiplos traumatismos devido à queda desde o quinto andar. Ambos os microrganismos foram obtidos da amostra de aspiração traqueal e identificados por Vitek®2 Compact. A identificação de P. multocida foi validada por espectrometria de massas (MALDI-TOF MS) e apresentou sensibilidade à penicilina, cefotaxima, amoxicilina-ácido clavulânico, ciprofloxacina, tetraciclina e trimetoprim-sulfometoxazol. S. aureus era meticilino sensível sem resistência acompanhante.

Detection and expression of SapS, a class C nonspecific acid phosphatase with O-phospho-L- tyrosine-phosphatase activity, in Staphylococcus aureus isolates from patients with chronic osteomyelitis / Detección y expresión de SapS, una fosfatasa ácida no específica de clase C con actividad de fosfatasa O-fosfotirosina, en aislamientos de Staphylococcus aureus de pacientes con osteomielitis crónica

Introduction. The identity of Staphylococcus aureus virulence factors involved in chronic osteomyelitis remains unresolved. SapS is a class C non-specific acid phosphatase and a well-known virulence factor that has been identified in S. aureus strain 154 but in protein extracts from rotting vegetables. Objective. To identify the SapS gene and characterize the activity of SapS from S. aureus strains: 12 isolates from bone infected samples of patients treated for chronic osteomyelitis and 49 from a database with in silico analysis of complete bacterial genomes. Materials and methods. The SapS gene was isolated and sequenced from 12 S. aureus clinical isolates and two reference strains; 49 S. aureus strains and 11 coagulase-negative staphylococci were tested using in silico PCR. Culture media semi-purified protein extracts from the clinical strains were assayed for phosphatase activity with p-nitro-phenyl- phosphate, O-phospho-L-tyrosine, O-phospho-L-serine, and OphosphoL-threonine in conjunction with various phosphatase inhibitors. Results. SapS was detected in the clinical and in-silico S. aureus strains, but not in the in silico coagulase-negative staphylococci strains. Sec-type I lipoprotein-type N-terminal signal peptide sequences; secreted proteins, and aspartate bipartite catalytic domains coding sequences were found in the SapS nucleotide and amino acid sequence analysis. SapS dephosphorylated with p-nitro-phenyl-phosphate and ophosphoLtyrosine were selectively resistant to tartrate and fluoride, but sensitive to vanadate and molybdate. Conclusion. SapS gene was found in the genome of the clinical isolates and the in silico S. aureus strains. SapS shares biochemical similarities with known virulent bacterial, such as protein tyrosine phosphatases, suggesting it may be a virulence factor in chronic osteomyelitis.

Introducción. Se desconoce la identidad de los factores de virulencia de Staphylococcus aureus implicados en la osteomielitis crónica. Sin embargo, SapS, una fosfatasa ácida no específica de clase C, es un factor de virulencia reconocido y ya fue identificada en la cepa 154 de S. aureus, pero en extractos proteicos de vegetales podridos. Objetivo. Detectar el gen SapS y caracterizar la actividad de la fosfatasa SapS en cepas de S. aureus aisladas de pacientes con osteomielitis crónica y en las reportadas en una base de datos de análisis in silico de genomas bacterianos completos. Materiales y métodos. Se aisló y secuenció el gen SapS en los 12 aislamientos clínicos de S. aureus y en dos cepas de referencia; estas secuencias se analizaron junto con las secuencias de las cepas reportadas en la base de datos de genomas bacterianos: 49 cepas de S. aureus y 11 cepas de estafilococos negativos para coagulasa. Se evalúo la actividad de la fosfatasa SapS, presente en los extractos de los sobrenadantes de los cultivos de las cepas clínicas, mediante la hidrólisis de fosfato p-nitrofenil, O-fosfo-L- tirosina, O-fosfo-L serina y O-fosfo-L treonina junto con varios inhibidores de fosfatasas. Resultados. Se detectó el gen SapS en el genoma de las cepas clínicas y en las 49 cepas de S. aureus analizadas in silico, pero no en las 11 cepas de estafilococos negativos para coagulasa. La secuenciación de SapS reveló un péptido señal presente en el extremo N-terminal de proteínas extracelulares y los dominios bipartitos de aspartato (DDDD) en su sitio catalítico. SapS hidroliza selectivamente el fosfato p-nitrofenil y la O-fosfo-L-tirosina, pero es sensible a vanadato y molibdato. Conclusión. Se encontró SapS en el genoma de S. aureus de las cepas clínicas y de las cepas de simulación computacional. La SapS con actividad específica para la hidrólisis de la O-fosfo-L-tirosina comparte similitudes bioquímicas con las fosfatasas-tirosina bacterianas, por lo que puede formar parte de la red de factores de virulencia de la osteomielitis crónica.

Shock séptico en niños con bacteriemia por Staphylococcus aureus de la comunidad en un hospital pediátrico de alta complejidad / Septic shock in children with community acquired Staphylococcus aureus bacteremia in a high complexity pediatric hospital

INTRODUCCIÓN: La información disponible sobre los factores de riesgo para el desarrollo de shock séptico es escasa, especialmente en población pediátrica. OBJETIVO: Describir las características epidemiológicas y clínicas de los niños con bacteriemia adquirida en la comunidad por Staphylococcus aureus y comparar las características de los pacientes con y sin shock séptico. PACIENTES Y MÉTODOS: Estudio de cohorte retrospectivo. Criterios de inclusión: niños entre 30 días y 16 años de edad, internados en el Hospital de Pediatría Juan P. Garrahan entre enero de 2017 y diciembre de 2019 por infecciones adquiridas en la comunidad con desarrollo de S. aureus en hemocultivos. Criterios de exclusión: antecedente de internación dentro de los 3 meses previos al ingreso, vivir en una comunidad cerrada, presencia de catéter de larga permanencia, dispositivos intraventriculares o intraperitoneales. Análisis estadístico: STATA 16. RESULTADOS: Se incluyeron 142 niños. 21 niños (15%) presentaron shock séptico. En el análisis multivariado, se asociaron con shock séptico, la bacteriemia persistente (OR 7,15; IC95% 4,39-23,81; p: 0,001) y el foco secundario de infección (OR 6,72; IC 95% 2,02-22,2; p 0,002). La mortalidad relacionada con la infección fue 3,5% (5 pacientes). CONCLUSIONES: El shock séptico se asoció con la bacteriemia persistente y la presencia de focos secundarios de infección.

BACKGROUND: Available information about risk factors for the development of septic shock is scarce, especially in the pediatric population. AIM: To describe the epidemiological and clinical characteristics of children with community-acquired Staphylococcus aureus bacteremia and to compare the characteristics of children with and without septic shock. METHODS: Retrospective cohort study. Inclusion criteria: Children between 30 days and 16 years old, hospitalized in the Juan P. Garrahan Pediatric Hospital between January 2017 and December 2019 for community-acquired infections with S. aureus isolation in blood cultures. Exclusion criteria: History of hospitalization within 3 months prior to admission, living in a closed community, presence of long-term catheter, intraventricular or intraperitoneal devices. Statistical analysis: STATA 16. RESULTS: 142 children were included. 21 children (15%) experienced septic shock. On multivariate analysis, persistent bacteremia (OR 7.15, 95% CI 4.39-23.81, p: 0.001) and secondary focus of infection (OR 6.72, 95% CI 2.02-22.2, p 0.002) were associated with septic shock. The infection-related mortality rate was 3.5% (5 patients). CONCLUSIONS: Septic shock was associated with persistent bacteremia and the presence of secondary foci of infection.

Prevalencia de colonización nasal por Staphylococcus aureus meticilino resistente en estudiantes de medicina de la Pontificia Universidad Católica de Chile: comparación entre estudiantes no expuestos a la clínica (pre-clínicos) y clínicos

Objetivos: El objetivo primario de este estudio fue determinar la prevalencia de colonización nasal por Staphylococcus aureus meticilino resistente (SAMR) en estudiantes de medicina en cursos pre-clínicos versus clínicos de la Pontificia Universidad Católica de Chile y describir el patrón epidemiológico, clínico y molecular de las cepas de SAMR obtenidas. Pacientes y Método: Se realizó un estudio descriptivo transversal a 299 estudiantes de pregrado y postgrado de medicina de la Pontificia Universidad Católica de Chile, 44 alumnos de primer año y 29 de segundo año, correspondiendo éstos a alumnos de cursos sin exposición clínica habitual y 26 alumnos de sexto año, 58 de séptimo año y 142 residentes, los cuales están diariamente expuestos a ambientes hospitalarios. Resultados: Se encontró una portación de 0% (0/73) en estudiantes no expuestos a la clínica (cursos pre-clínicos) y de 0,9% (2/226) en estudiantes de cursos clínicos, diferencia que no fue estadísticamente significativa (valor p 0,42). Conclusiones: La portación nasal de SAMR en el personal de salud de este trabajo fue baja, encontrando muestras positivas solo en estudiantes con exposición clínica. Esta prevalencia es similar a la reportada en otros trabajos de características similares realizados en Chile.

Objectives: The primary objective of this study was to determine the prevalence of nasal colonization of methicillin resistant Staphylococcus aureus (MRSA) in medical students in pre-clinical versus clinical courses at the Pontificia Universidad Católica de Chile and to describe the epidemiological, clinical and molecular pattern of the MRSA strains obtained. Method: A cross-sectional descriptive study was carried out on 299 undergraduate and graduate medical students from the Pontificia Universidad Católica de Chile, 44 first-year students and 29 second-year students, corresponding to students of courses without regular clinical exposure and 26 sixth-year students, 58 seventh-year and 142 residents, who are daily exposed to hospital environments. Results: A carriage of 0% (0/73) was found in students not exposed to the clinic (pre-clinical courses) and 0.9% (2/226) in students of clinical courses, a difference that was not statistically significant (p-value 0.42). Conclusions: The MRSA nasal carriage found in our medical students was low, finding positive samples only in students with clinical exposure. This prevalence is similar to the one reported in other studies in Chile with similar characteristics.

Infecciones causadas por Staphylococcus aureus de la Comunidad. Estudio de sensibilidad y tendencias en población pediátrica. Años 2015 a 2020

Introducción: Staphylococcus aureus (SA) puede ocasionar cuadros infecciosos severos y muerte. La emergencia de cepas resistentes a meticilina constituye un desafío terapéutico. Objetivos: determinar el perfil de resistencia antimicrobiana de: Staphylococcus aureus adquirido en la comunidad (SA-CA), obtenidos de muestras biológicas de niños, entre 2015 a 2020. Material y Método: estudio descriptivo, observacional y retrospectivo. Las muestras para cultivos se extrajeron al ingreso hospitalario del paciente. Para determinación de resistencia y sensibilidad se utilizó normas de CSLI. Resultados: 244 aislamientos de SA-CA. Masculinos 99 (59%), menores de un año: 42 (25%), de 2 a 5 años: 34 (20%), de 6 a 11 años: 50 (30%) y entre 12 a 15 años: 42 (25%). De los aislados, 72% fueron SAMR (121/168) y 28% SAMS (47/168). Se observó un incremento de tasas anuales de aislamientos SAMR en infecciones de la comunidad desde el 2015 al 2020. Los aislamientos se originaron en piel y partes blandas 53,2 %; sangre 37,4%, orina 3,5%, LCR 2,4%, liquido articular 1,7%, abscesos profundos 1,2% y liquido pleural 0,6%. La prevalencia de SAMR-CA fue de 60,5 en el 2015, 59,6 %, 61,5%, 72,2 %, 67,3% y 75,5 % en los años sucesivos. No se aisló ninguna cepa resistente a la vancomicina. El 10,1% de las cepas estudiadas presentó resistencia inducida a la clindamicina. Conclusión: El SAMR se ha establecido como patógeno de la comunidad. La resistencia inducida por clindamicina fue del 10,1%. Un tercio de las infecciones fueron causadas por SAMS. Las prevalencias de SAMS muestran tendencia a la disminución.

Introduction: Staphylococcus aureus (SA) can cause severe infectious conditions and death. The emergence of methicillin-resistant strains constitutes a therapeutic challenge. Objectives: to determine the antimicrobial resistance profile of: Staphylococcus aureus acquired in the community (SA-CA), obtained from biological samples of children, between 2015 and 2020. Material and Method: descriptive, observational and retrospective study. The samples for cultures were extracted upon hospital admission of the patient. To determine resistance and sensitivity, CSLI standards were used. Results: 244 isolates of SA-CA. Males 99 (59%), under one-year-old: 42 (25%), from 2 to 5 years old: 34 (20%), from 6 to 11 years old: 50 (30%) and between 12 and 15 years old: 42 (25%). Of the isolates, 72% were SAMR (121/168) and 28% SAMS (47/168). An increase in annual rates of MRSA isolates in community infections was observed from 2015 to 2020. The isolates originated in skin and soft parts 53.2 %; blood 37.4%, urine 3.5%, CSF 2.4%, joint fluid 1.7%, deep abscesses 1.2% and pleural fluid 0.6%. The prevalence of MRSA-CA was 60.5 in 2015, 59.6%, 61.5%, 72.2%, 67.3%, and 75.5% in subsequent years. No vancomycin resistant strain was isolated. 10.1% of the strains studied presented induced resistance to clindamycin. Conclusion: MRSA has been established as a community pathogen. The resistance induced by clindamycin was 10.1%. One third of the infections was caused by SAMS. The prevalence of SAMS shows a downward trend.

Clinical Profile, Intensive Care Needs, and Short-Term Outcome of Toxic Shock Syndrome Among Children: A 10-Year Single-Centre Experience from North India

Objective To describe the clinical and laboratory profle, management, intensive care needs, and outcome of children with toxic shock syndrome (TSS) admitted to the pediatric intensive care unit (PICU) of a tertiary care center in North India. Methods This retrospective study was conducted in the PICU of a tertiary care hospital in North India over a period of 10 y (January 2011–December 2020) including children<12 y with TSS (n=63). Results The median (interquartile range, IQR) age was 5 (2–9) y, 58.7% were boys, and Pediatric Risk of Mortality III (PRISM-III) score was 15 (12–17). The primary focus of infection was identifed in 60.3% children, 44.5% had skin and soft tissue infections, and 17.5% (n=11) had growth of Staphylococcus aureus. Common manifestations were shock (100%), rash (95.2%), thrombocytopenia (79.4%), transaminitis (66.7%), coagulopathy (58.7%), and acute kidney injury (AKI) (52.4%); and involvement of gastrointestinal (61.9%), mucus membrane (55.5%), respiratory (47.6%), musculoskeletal (41.3%), and central nervous system (CNS) (31.7%). The treatment included fuid resuscitation (100%), vasoactive drugs (92.1%), clindamycin (96.8%), intravenous immunoglobulin (IVIG) (92.1%), blood products (74.6%), mechanical ventilation (58.7%), and renal replacement therapy (31.7%). The mortality was 27% (n=17). The duration of PICU and hopsital stay was 5 (4–10) and 7 (4–11) d, respectively. Higher proportion of nonsurvivors had CNS involvement, transaminitis, thrombocytopenia, coagulopathy, and AKI; required mechanical ventilation and blood products; and had higher vasoactive–inotropic score. Conclusion TSS is not uncommon in children in Indian setup. The management includes early recognition, intensive care, antibiotics, source control, and adjunctive therapy (IVIG and clindamycin). Multiorgan dysfunction and need for organ supportive therapies predicted mortality.

Inhibitory Effect of Gallium Nitrate against Staphylococcus aureus and Its Action on the Formation of Biofilms on Titanium Surfaces

Aims: This study aimed to investigate the effect of gallium nitrate [Ga(NO3)3], an inorganic antimicrobial agent, against the growth and biofilm formation of Staphylococcus aureus on the titanium surface. Study Design: This study is a laboratory investigation involving the determination of the inhibitory concentration (IC) of Ga(NO3) 3 against the planktonic strain of S. aureus and biofilm formation on titanium coupons. Place and Duration of Study: Sample: Center of Science and Technology for Sustainability (CCTS), Federal University of São Carlos, SP, Brazil, between March 2020 and March 2022. Methodology: The inhibitory concentration of gallium nitrate was determined in a 96-well microtiter plate in Muller Hinton broth. The potential of the antimicrobial agent to inhibit biofilm formation by S. aureus on titanium surfaces was evaluated by Scanning Electron Microscopy (SEM). The cytotoxicity potential of Ga(NO3)3 was determined on V79 cells. Results: The results showed that the susceptibility of gallium nitrate against S. aureus was 1.40 µM, while SEM images revealed that concentrations of 90 µM inhibited biofilm formation by S. aureus. Conclusion: This research has shown promising results regarding gallium nitrate's potential of inhibiting the growth of both planktonic and sessile S. aureus cells. In addition, coating titanium surfaces with Ga(NO3)3 would be an extra alternative to prevent implant-associated infections due to its non-toxicity to cells.

Repositioning of FDA-approved drugs for the treatment of methicillin-resistant Staphylococcus aureus infection: Structure-based virtual screening and in vitro assay

Background: Computer-aided repositioning of approved drugs is an increasingly popular strategy for the discovery of effective therapies. The potency of the newly repositioned drugs can be optimized using them as a component of an effective drug combination, thereby achieving the desired therapeutic effect at a lower and more tolerable drug concentration. Aim and Objectives: The aim of the study was to perform structure-based virtual screening and repurposing of FDA-approved drugs for the treatment of methicillin resistance by Staphylococcus aureus (SA) and perform an in vitro validation of the prediction. Materials and Methods: Following ethical clearance at the Department of Pharmacology and Therapeutics, College of Health Sciences, Usmanu Danfodiyo University Sokoto, molecular docking was performed against 5 validated protein targets involved in the development of methicillin resistance by SA and an in vitro validation of the prediction was done using 3 of the top-ranking drug candidates against methicillin-resistant vancomycin-susceptible strain of the pathogen (ATCC 43300). Results: Desmopressin and docetaxel, two of the 20 top-ranking repurposed drugs discovered through virtual screening, enhanced the inhibitory effect of oxacillin against the ATCC 43300 SA strain in a ratio-dependent manner, although each of the two drugs singly was only weakly effective against the bacterial strain. The standard drug, vancomycin (also among the top-scoring candidates), alone, was effective against ATCC 43300 strain and in combination with oxacillin, the two drugs produced a ratio-dependent synergistic effect against the bacterial strain. Conclusion: These findings suggest that oxacillin-based combinations with desmopressin, docetaxel, and the standard drug vancomycin, three of the 20 top-ranking drugs, at optimum ratios, may be beneficial in reversing the resistance of the ATCC 43300 SA strain to oxacillin, thus supporting the prediction of the molecular docking results.