Community-genotype methicillin-resistant Staphylococcus aureus skin and soft tissue infections in Latin America: a systematic review

ABSTRACT Background: Community-genotype methicillin-resistant Staphylococcus aureus (CG-MRSA) emerged in the 1990s as a global community pathogen primarily involved in skin and soft tissue infections (SSTIs) and pneumonia. To date, the CG-MRSA SSTI burden in Latin America (LA) has not been assessed. Objective: The main objective of this study was to report the rate and genotypes of community-genotype methicillin-resistant Staphylococcus aureus (CG-MRSA) causing community-onset skin and soft tissue infections (CO-SSTIs) in LA over the last two decades. In addition, this research determined relevant data related to SSTIs due to CG-MRSA, including risk factors, other invasive diseases, and mortality. Data sources: Relevant literature was searched and extracted from five major databases: Embase, PubMed, LILACS, SciELO, and Web of Science. Methods: A systematic review was performed, and a narrative review was constructed. Results: An analysis of 11 studies identified epidemiological data across LA, with Argentina presenting the highest percentage of SSTIs caused by CG-MRSA (88%). Other countries had rates of CG-MRSA infection ranging from 0 to 51%. Brazil had one of the lowest rates of CG-MRSA SSTI (4.5-25%). In Argentina, being younger than 50 years of age and having purulent lesions were predictive factors for CG-MRSA CO-SSTIs. In addition, the predominant genetic lineages in LA belonged to sequence types 8, 30, and 5 (ST8, ST30, and ST5). Conclusion: There are significant regional differences in the rates of CG-MRSA causing CO-SSTIs. It is not possible to conclude whether or not CG-MRSA CO-SSTIs resulted in more severe SSTI presentations or in a higher mortality rate.

Microbiologic characteristics and antibiotic resistance rates of diabetic foot infections / Perfil microbiológico e de resistência bacteriana no pé diabético infectado

ABSTRACT Purpose: the purpose of this research was to identify the sociodemographic and microbiological characteristics and antibiotic resistance rates of patients with diabetic foot infections, hospitalized in an emergency reference center. Methods: it was an observational and transversal study. The sociodemographic data were collected by direct interview with the patients. During the surgical procedures, specimens of tissue of the infected foot lesions were biopsied to be cultured, and for bacterial resistance analysis. Results: the sample consisted of 105 patients. The majority of patierns were men, over 50 years of age, married and with low educational level. There was bacterial growth in 95 of the 105 tissue cultures. In each positive culture only one germ was isolated. There was a high prevalence of germs of the Enterobacteriaceae family (51,5%). Gram-negative germs were isolated in 60% of cultures and the most individually isolated germs were the Gram-positive cocci, Staphylococcus aureus (20%) and Enterococcus faecalis (17,9%). Regarding antibiotic resistance rates, a high frequency of Staphylococcus aureus resistant to methicillin (63,0%) and to ciprofloxacin (55,5%) was found; additionally, 43,5% of the Gram-negative isolated germs were resistant to ciprofloxacin. Conclusions: the majority of patients were men, over 50 years of age, married and with low educational level. The most prevalent isolated germs from the infected foot lesions were Gram-negative bacteria, resistant to ciprofloxacin, and the individually most isolated germ was the methicillin resistant Staphylococcus aureus.

RESUMO Objetivo: identificar o perfil sociodemográfico, microbiológico e de resistência bacteriana em pacientes com pé diabético infectado. Métodos: tratou-se de estudo observacional, transversal que avaliou os perfis sóciodemográfico e microbiológico de pacientes portadores de pé diabético infectado internados em Pronto Socorro de referência. Os dados sociodemográficos foram coletados por meio de entrevista. Foram colhidos, durante os procedimentos cirúrgicos, fragmentos de tecidos das lesões podais infectadas para realização de cultura/antibiograma. Resultados: a amostra foi composta por 105 pacientes. O perfil sociodemográfico mais prevalente foi o de pacientes do sexo masculino, acima dos 50 anos, casados e com baixa escolaridade. Das 105 amostras de fragmentos de tecidos colhidos para realização de cultura e antibiograma, 95 foram positivas, com crescimento de um único germe em cada um dos exames. Houve predomínio de germes da família Enterobacteriaceae (51,5%). Germes Gram-negativos foram isolados em 60,0% das culturas e os espécimes mais isolados individualmente foram os cocos Gram-positivos, Staphylococcus aureus (20,0%) e Enterococcus faecalis (17,9%). Considerando-se os perfis de resistência bacteriana, verificou-se alta taxa de Staphylococcus aureus resistente à meticilina (63,0%) e à ciprofloxacino (55,5%); verificou-se, também, que 43,5% dos germes Gram-negativos eram resistentes à ciprofloxacino. Conclusões: o perfil sociodemográfico majoritário, foi o de homens, com mais de 50 anos e com baixa escolaridade. Concluímos que os germes mais prevalentes nas lesões podais dos pacientes diabéticos foram os Gram-negativos, resistentes ao ciprofloxacino e que o germe mais isolado individualmente foi o Staphylococcus aureus resistente à meticilina.

Caracterización de los pacientes con bacteriemia por Staphylococcus aureus resistente a la meticilina en un hospital militar de alta complejidad / Characterization of patients with bacteremia by methicillin-resistant Staphylococcus aureus in a high-complexity military hospital

Resumen Introducción. En las Fuerzas Militares de Colombia, cerca de 500.000 de sus miembros asisten a consulta en los establecimientos sanitarios militares. En esta población, Staphylococcus aureus resistente a la meticilina (SAMR) se ha convertido en un agente patógeno de gran incidencia. Objetivo. Caracterizar los pacientes con diagnóstico de bacteriemia por SAMR en el Hospital Militar Central entre el 2012 y el 2015. Materiales y métodos. Se llevó a cabo un estudio observacional descriptivo de revisión retrospectiva de historias clínicas de pacientes mayores de 18 años, hospitalizados y con hemocultivos positivos para S. aureus resistente a la meticilina. Para la identificación de los pacientes se empleó el sistema Whonet, version 5.6. Resultados. De los 177 cultivos positivos para S. aureus, el 24,8 % (n=44) correspondió a SAMR, con mayor prevalencia en pacientes militares activos(n=20m 45,4 %). Se observó una frecuencia similar para la bacteriemia por SAMR adquirida en la comunidad y la adquirida en el hospital, siendo más frecuente (n=37, 84 %) el fenotipo de la comunidad en ambos grupos. El principal foco infeccioso fueron los tejidos blandos, seguidos por el tejido pulmonar. Se presentaron mayores tasas de complicaciones (61%, n=13) en la bacteriemia adquirida en el hospital; 34,9 % (n=15),de los pacientes tuvieron una estancia hospitalaria prolongada atribuible a las complicaciones desencadenadas por la bacteriemia. Conclusiones. La población más afectada por SAMR fueron los pacientes militares activos (n=20, 45,4 %), con una frecuencia similar de la bacteriemia adquirida en la comunidad (n=18, 43,2 %) y la adquirida en el hospital (n=25, 56,8 %), y el principal foco infeccioso fueron los tejidos blandos. Dados estos resultados, es necesario adelantar estudios para establecer la prevalencia de infecciones por SAMR en la piel.

Abstract Introduction: In Colombia, there are about 500,000 members in the national armed forces who consult military health institutions. In this population, methicillin-resistant Staphylococcus aureus (MRSA) has become a high-incidence pathogen. Objective: The aim of this study was to characterize patients with MRSA bacteremia in the Hospital Militar Central between 2012 and 2015. Materials and methods: This was an observational descriptive study with a retrospective review of clinical histories of hospitalized patients older than 18 years of age with positive blood cultures for methicillin-resistant S. aureus. The identification of the patients was made using the Whonet system, version 5.6. Results: From cultures positive for S. aureus, 24.8% were methicillin-resistant strains, with a higher prevalence in active military personnel. A similar frequency was observed for community-acquired MRSA bacteremias and those acquired at the hospital, with the community phenotype being the most frequent in both groups. The main infectious focus related to the development of bacteremia was soft tissue, followed by pulmonary tissue. There were higher complication rates in nosocomial bacteremias; 34.9% of the patients had prolonged stays attributable to complications triggered by the bacteremia. Conclusions: Active military personnel was the most affected population by MRSA, with a similar frequency in community-acquired and nosocomial bacteremias. The main infectious focus was soft tissue. Taking into account these data, studies that establish the prevalence of skin infections by MRSA should be carried out.

Características clínicas y microbiológicas de las infecciones de piel y tejidos blandos por Staphylococcus aureus en niños de un hospital en Medellín durante los años 2013 a 2015 / Clinical and microbiological characteristics of skin and soft tissue infections caused by Staphylococcus aureus in children in a hospital in Medellin from 2013 to 2015

Resumen Introducción: El principal microorganismo implicado en las infecciones de piel y tejidos blandos (IPTB) es Staphylococcus aureus, con incremento en las cepas resistentes a meticilina en los últimos años. Objetivo: Identificar la frecuencia de S. aureus resistente a meticilina (SARM) en IPTB en niños que consultaron a un hospital de cuarto nivel en la ciudad de Medellín. Métodos: Estudio descriptivo, retrospectivo, a partir de la revisión de historias clínicas. Se incluyeron pacientes menores de 18 años con IPTB causadas por S. aureus que no cumplieran con criterios de enfermedad invasora. Resultados: La prevalencia de SARM en esta población fue de 31%. El principal diagnóstico fue absceso cutáneo (68%), seguido por infección de sitio quirúrgico (15%) y celulitis no purulenta (6%). Tenían alguna co-morbilidad 85% de los pacientes. Todos los aislados fueron sensibles a rifampicina y cotrimoxazol. Ocho por ciento de los aislados fueron resistentes a clindamicina. Se encontró mayor prevalencia de SARM en lactantes comparado con los mayores de 2 años (60 vs 23%, p = 0,0109). Conclusión: Ante la alta prevalencia de SARM en IPTB se recomienda incluir en el tratamiento empírico antimicrobianos con cobertura para estas cepas, principalmente para lactantes.

Background: Skin and soft tissue infections (SSTI) are very common in children and Staphylococcus aureus is the main agent, with an increase of methicillin resistant strains (MRSA) in recent years. Aim: To identify the frequency of MRSA in skin and soft tissue infections (SSTI) in children from a high complex hospital in Medellin, Colombia. Methods: This is a descriptive, retrospective study, information was obtained from medical records. We included patients younger than 18 years with SSTI due to S. aureus who did not meet criteria for invasive disease. Results: The prevalence of MRSA in this population was 31%. The main diagnosis was cutaneous abscess (68%), followed by surgical site infection (15%) and non-purulent cellulitis (6%). Eighty five percent of the patients had at least 1 comorbidity. All isolates were sensitive to rifampicin and cotrimoxazole and 8% of the isolates were resistant to clindamycin. There was a higher prevalence of MRSA in patients under 2 years compared to older (60 vs 23%, p = 0,0109). Conclusion: In view of the high prevalence of MRSA in SSTI, empirical treatment with adequate coverage for MRSA is recommended, especially for patients under 2 years of age.

Community-associated methicillin-resistant Staphylococcus aureus in non-outbreak skin infections

The aim of this study was to determine the prevalence of Staphylococcus aureus and risk factors for the acquisition of MRSA (Methicillin Resistant Staphylococcus aureus) as the main cause of skin and soft tissue infections. S. aureus were characterized for the presence of PVL, TSST-1 and mecA genes. SCCmec typing was carried out in mecA positive strains and PFGE was performed only in these strains. During the study period, 127 outpatients attending a dermatology clinical the Botucatu Medical School, a regional tertiary hospital in Botucatu, Sao Paulo, Brazil, were diagnosed with active skin infections. A total 66 (56.9%) S. aureus strains were isolated. The methicillin resistance gene mecA was detected in seven (10.6%) S. aureus strains. The SCCmec types detected in the seven mecA-positive S. aureus strains were type Ia in one, type II in three, and type IV in three. The PVL gene was detected in 10 (15.1%) in sensitive strains. Pulsed field gel electrophoresis revealed non-clonal diversity among the isolates. The risk factors associated with MRSA acquisition in this study were previous ciprofloxacin use and working in a healthcare environment. The risk factors indicate plausible routes of CA-MRSA transmission among the subjects studied.

Skin infections in male pupils of primary schools in Al Ahsa

To determine the prevalence, the nature, and the possible socio-demographic risk factors involved in the development of common transmissible skin disorders [TSD] among the studied population. A cross-sectional consecutive survey was carried out from November 15, 2008 to May 14, 2009 in Al-Ahsa governorate. This study included 1337 male primary school children. Data were collected using the following tools: Socio-demographics and hygienic habits according to pre-established forms and a thorough dermatological examination of all the included children. The prevalence of TSD was 27.15% with a statistically significant difference according to rural/urban locations [33.74% vs. 22.27%]. Fungal infections were the leading diseases [9.1%] followed by bacterial infections [8.9%], parasitic infestations [4.3%], and viral infections [4.1%]. TSD were significantly more frequent in students whose fathers have a primary or preparatory educational status and in the students having the habit to play barefooted. Our study found that TSD was relatively frequent among male primary school students in Al-Ahsa. Our study has several limitations. One major limitation is that female primary school students were excluded from the study. Despite this major limitation, we hope the findings may be useful in planning health care programs for Saudi children with the hope of reducing the prevalence of TSD in the future

Bacteriemia en pacientes internados con celulitis / Bacteremia in patients hospitalized with cellulitis

La celulitis es una inflamación aguda de la dermis y tejido celular subcutáneo de causa bacteriana, que generalmente complica a heridas, úlceras y dermatosis, aunque de manera frecuente no existe sitio de entrada. Se recomienda la realización de cultivo de punción de piel y partes blandas (PPB). Los hemocultivos raramente dan resultados positivos. El objetivo de este trabajo fue determinar la prevalencia de bacteriemia en pacientes internados en nuestra institución con diagnóstico de celulitis. Se analizaron retrospectivamente los registros clínicos de los pacientes con este diagnóstico al ingreso entre junio de 2007 y marzo de 2010. Se evaluaron los datos poblacionales, presencia de comorbilidades, y resultados de los cultivos. En ese período, se internaron 140 pacientes con diagnóstico de celulitis y a todos ellos se les realizó hemocultivo y cultivos de PPB. Setenta y cuatro eran varones (52.8%). La edad promedio: 47.5 ± 19.7 años (rango 16-94). El 40% tuvo cultivos positivos de PPB, en los que el Staphylococcus aureus meticilino resistente (SAMR) fue el germen más frecuentemente aislado (35.7%); la prevalencia de bacteriemia fue del 8.6%, en donde el germen más frecuente fue Streptoccocus Beta hemolítico, grupo G (33% del total de hemocultivos positivos). La bacteriemia se asoció significativamente a mayor estadía hospitalaria (10.5 ± 8.9 vs. 4.9 ± 6, p = 0.004). Se asoció con mayor riesgo de hemocultivo positivo a ser diabético, tener cultivo de PPB positivo, consumo de alcohol y/o enfermedad pulmonar obstructiva crónica.

Cellulitis is an acute inflammation of dermis and subcutaneous tissue, usually complicating wounds, ulcers, or dermatosis. Even though in these cases it is recommended to perform culture from skin and soft tissue samples, the utility of blood cultures remains controversial due to the low frequency of positive results. Here we report the prevalence of bacteremia in patients with cellulitis admitted in our Hospital, and evaluate the presence of risk factors associated with the occurrence of this event. Clinical records of patients with diagnosis of cellulitis admitted between June 2007 and March 2010 were retrospectively reviewed. Patients without skin and soft tissue culture and/or blood cultures were excluded. Demographic data, presence of comorbidities, and culture results were analyzed. In this period, 140 patients were admitted with this diagnosis. Fifty six (40%) of them had positive skin and soft tissue cultures; where methicillin resistant Staphylococcus aureus (MRSA) was the most frequently isolated bacterium species (35.7%). Bacteremia was detected in 8.6% of these cases, where the most frequently isolated bacteria were Group G Beta haemolytic Streptococcus (33%). Bacteremia was significantly associated with longer hospital stay (10.5 ± 8.98 vs. 4.9 ± 6, p = 0.004). The following variables were significantly associated with the occurrence of positive blood cultures: diabetes (41.7% vs. 14.1%; p = 0.02; OR 4.4), positive skin and soft tissue culture (75% vs. 35.2%; p = 0.01; OR 5.5), alcoholism (16.7% vs. 3.9%; p = 0.01; OR 4.9), and chronic obstructive pulmonary disease (16.7% vs. 0.78%; p = 0.01; OR 25.4).

Methicillin resistant staphylococcus aureus prevalence amongst community versus hospital acquired skin and soft tissue infections

Methicillin resistant Staphylococcus aureus [MRSA] is becoming increasingly prevalent, not only in the hospital acquired but also the community acquired infections. Skin and soft tissues are a few of the important targets for this pathogen. A study was conducted at the departments of surgery, dermatology and pathology, Combined Military Hospital, Gujranwala Cantt to know the prevalence of MRSA amongst community vs. hospital acquired skin and soft tissue infections [SSTIs]. A total of 216 community acquired and 48 hospital acquired SSTIs were included in the study. The pus swabs/pus specimens collected from all the cases were processed for routine cultures. Isolates were identified as Staphylococcus aureus and resistance to methicillin was detected using standard techniques. Staphylococcus aureus was isolated in 64.35% of the community acquired and 72.91% of the hospital acquired SSTIs. Prevalence of MRSA amongst community acquired SSTIs was 26.6% while in the hospital acquired SSTIs was 68.57%. The study indicates quite a high prevalence of MRSA amongst community acquired and a very high prevalence in hospital acquired SSTIs. Further large scale studies are required to monitor the prevalence and spread of MRSA amongst SSTIs

Enfermedad invasora por Staphylococcus aureus meticilino: resistente adquirida en la comunidad / Community-acquired methicillin-resistant Staphylococcus aureus disseminated disease

Se presenta un caso de enfermedad invasora por Staphylococcus aureus meticilino resistente (SAMR)adquirido en la comunidad (SAMR-c). Paciente varón de 21 años, previamente sano, que consultó por nódulos subcutáneos compatibles con gomas. La ultrasonografía reveló múltiples abscesos subcutáneos e imágenes consistentes con piomiositis, además de derrame pleural y pericárdico. En el cultivo del material purulentoobtenido por punción-aspiración con aguja fina de las lesiones se aisló S. aureus. El antibiograma por difusiónmostró resistencia a cefalotina, eritromicina y clindamicina, y sensibilidad a trimetroprima-sulfametoxazol, ciprofloxacina y rifampicina. La meticilino resistencia se confirmó por aglutinación con partículas de látex sensibilizadas con anticuerpos monoclonales dirigidos contra la proteína ligadora de penicilina 2A. El paciente fue tratado con ciprofloxacina y rifampicina durante cuatro semanas, con evolución favorable. La frecuencia de infecciones por SAMR-c está en aumento, observándose en personas sin factores de riesgo aparentes. Esto llevaría a fracaso en el tratamiento empírico para infecciones de la comunidad en los que se presume etiología estafilocócica

A 21 year old man, previously healthy, presented with subcutaneous nodes consistent with gummas. Ultrasonography disclosed multiple subcutaneous abscesses and images suitable with piomiositis, pleural and pericardium effusion. A puncture-aspirate with fine-needle was performed and produced purulent material, with isolate of Staphylococcus aureus. Antimicrobial susceptibility testing by disk diffusion showed resistant to cefalotin, erythromycin and clindamycin, and susceptibility to trimethoprim-sulfamethoxazole, ciprofloxacin and rifampicin. Methicilin-resistance was confirmed by Staphyslide agglutination testing (Biomérieux). The patient was treatedwith ciprofloxacin and rifampicin during four weeks, with a good clinical response. The frequency of CA-MRSAinfections is increasing, and these are reported in patients without identified predisposing risks leading to failureon empiric therapy for community infections presumed to be due to staphylococcal agent

Infecciones de piel y partes blandas en pacientes ambulatorios / Skin and soft tissue infection in outpatients

Introducción: en la última década se ha informado a nivel mundial la emergencia de infecciones causadas por cepas de Staphylococcus aureus meticilino-resistente (SAMR) sin los factores de riesgo clásicos descriptos para portar este germen, con un patrón de susceptibilidad diferente a los antibióticos y adquirido en la comunidad. En nuestro país las primeras comunicaciones de infecciones producidas por este germen fueron en el año 2001 en niños con infecciones de piel y partes blandas internados en el Centro Hospitalario Pereira Rossell (CHPR).Objetivo: 1) Analizar las características clínicas y la etiología de las infecciones de piel y partes blandas en pacientes ambulatorios. 2) Determinar en estas infecciones la prevalencia de Staphylococcus aureus meticilino-resistente adquirido en la comunidad (SAMR-com) y su sensibilidad a los antibióticos. Material y métodos: se realizó un estudio descriptivo, prospectivo, de pacientes que consultaron en el Departamento de Emergencia Pediátrica del CHPR por infecciones de piel y partes blandas adquiridas en la comunidad, en el período 24 de marzo de 2004 al 31 de julio de 2004, tratados en forma ambulatoria y en los que se aisló una bacteria de las muestras obtenidas para estudio bacteriológico. Se incluyeron pacientes con impétigo, forúnculo, absceso, celulitis a punto de partida cutáneo, panadizo y herida o quemadura sobreinfectada. Se analizaron datos demográficos, factores de riesgo para portar SAMR, características clínicas de los pacientes y análisis bacteriológico de los resultados de las muestras obtenidas de acuerdo al informe realizado por el Laboratorio Central del CHPR, sección Bacteriología. Resultados: se incluyeron 297 pacientes. Los diagnósticos clínicos realizados fueron: impétigo 122 (48,4 por ciento), forúnculo 29 (11,5 por ciento), celulitis 19 (7,5 por ciento), absceso 30 (11,9 por ciento), panadizo ocho (3,2 por ciento), heridas o quemaduras infectadas seis (2,4 por ciento) y coexistencia de alguna...

Methicillin resistant Staphylococcus aureus

The prevalence of methicillin resistant Staphylococcus aureus (MRSA) at the General Hospital, Port-of-Spain, between June 1995 and May 1996 was determined. The MRSA prevalence rate was 4.6of all S aureus isolates, with all but one nosocomially acquired. 15 isolates were associated with infections, and three were colonizing strains. 17 of the 18 patients with MRSA had received antibiotics previously, including 13 who had received multiple antibiotics. Skin and soft tissue were the sites of infection and colonization in 12 cases; and surgical wards and the Intensive Care Unit (ICU) accounted for 16 MRSA isolates. All isolates were sensitive to vancomycin and all but one were resistant to gentamicin. MRSA occurred sporadically in a wide distribution of wards and physicians' services, although the isolation of three strains from the ICU and three strains from a surgical ward were temporally related. Only one of two deaths was attributable to MRSA. Control of the spread of MRSA in this hospital must include the reinforcement of the appropriate use of antibiotics, hand washing and appropriate isolation of patients in the surgical and intensive care wards.