Infección por Serratia marcescens: una inusual causa de lesiones cutáneas / Serratia marcescens infection: an unusual cause of skin lesions

Serratia marcescens corresponde a un bacilo gram negativo, miembro de la familia Enterobacteriaceae. Este microorganismo tiene una alta capacidad de supervivencia en condiciones hostiles y ha sido implicado en infecciones del tracto respiratorio, vía urinaria, meningitis, endocarditis y sistema musculoesquelético. No obstante, es considerado una causa rara de infecciones cutáneas. Esta última tiene distintas presentaciones clínicas, la más frecuente es fascitis necrotizante seguida de celulitis. Los nódulos, las pápulas después de inyecciones de rellenos, las erupciones papulares diseminadas, las placas eritematosas, las pústulas y las úlceras son parte del amplio espectro de formas clínicas descritas en la literatura. Presentamos el caso de una paciente de 50 años, con historia de compromiso del estado general, lesiones cutáneas polimorfas y fiebre. Se confirmó una infección cutánea por Serratia marcescens mediante cultivos. Se destaca el polimorfismo y la coexistencia de distintas manifestaciones en una misma paciente, incluyendo celulitis, nódulo, ulceras y necrosis cutánea y la importancia del estudio microbiológico para el adecuado tratamiento antibiótico.

Serratia marcescens corresponds to gram negative bacillus, a member of the Enterobacteriaceae family. This microorganism has a high survival capacity in hostile conditions and has been implicated in respiratory tract, urinary tract, meningitis, endocarditis and musculoskeletal system infections. However, it is considered a infrequent cause of cutaneous infections. Has different clinical presentations, the most frequent is necrotizing fasciitis followed by cellulite. Nodules, papules after filler injections, disseminated papular eruption, erythematous plaques, pustules and ulcers are part of the broad spectrum of clinical forms described in the literature. We present the case of a 50 year old patient with a history of compromised general condition, polymorphic cutaneous lesions and fever. Serratia marcescens cutaneous infection was confirmed by cultures. The polymorphism and the coexistence of different manifestations in the same patient, including cellulitis, nodule, ulcers and skin necrosis, and the importance of the microbiological study for the adequate antibiotic treatment are highlighted.

Enfermedad granulomatosa crónica: infecciones múltiples como forma de presentación. Caso clínico pediátrico / Chronic granulomatous disease: multiple infections as clinical presentation. Pediatric case report

La enfermedad granulomatosa crónica es una inmunodeficiencia primaria infrecuente, debida a un defecto en la actividad microbicida de los fagocitos, originada por mutaciones en los genes que codifican alguna de las subunidades del complejo enzimático nicotinamida adenina dinucleótido fosfato oxidasa. La incidencia estimada es 1 en 250 000 recién nacidos vivos. Puede presentarse desde la infancia hasta la adultez, por lo general, en menores de 2 años. Las infecciones bacterianas y fúngicas, en conjunto con las lesiones granulomatosas, son las manifestaciones más habituales de la enfermedad. Los microorganismos aislados más frecuentemente son Aspergillus spp., Staphylococcus aureus, Serratia marcescens, Nocardia spp. Se reporta el caso clínico de un varón de 1 año de vida en el que se diagnosticó enfermedad granulomatosa crónica a partir de infecciones múltiples que ocurrieron simultáneamente: aspergilosis pulmonar invasiva, osteomielitis por Serratia marcescens y granuloma cervical por Enterobacter cloacae.

Chronic granulomatous disease is an uncommon primary immunodeficiency due to a defect of the killing activity of phagocytes, caused by mutations in any of the genes encoding subunits of the superoxide-generating phagocyte NADPH oxidase system. The incidence is 1 in 250 000 live births. It can occur from infancy to adulthood, usually in children under 2 years. Bacterial and fungal infections in association with granuloma lesions are the most common manifestations of the disease. Aspergillus species, Staphylococcus aureus, Serratia marcescens, Nocardia species are the most common microorganisms isolated. We describe here a case of a 1-year-old boy with chronic granulomatous disease and invasive pulmonary aspergillosis, Serratia marcescens osteomyelitis and Enterobacter cloacae cervical granuloma.

Brote por Serratia marcescens en una Unidad de Cuidados Intensivos Neonatales: Guayaquil-Ecuador / Serratia marcescens outbreak in Neonatal Intensive Care Unit: Guayaquil, Ecuador

We report a Serratia marcescens outbreak occurred in the NICU of a pediatric hospital in Guayaquil, Ecuador. Nine cases of infection were detected, from which septicemia was developed in 55.5%. The index case was a newborn derived from another institution with septic arthritis caused by the outbreak strain. The infection rate was 17.6% and mortality rate was 33.3%. All isolates were resistant to aminoglycosides and susceptible to third generation cephalosporins and carbapenems. Clonality analysis by pulsed-field gel electrophoresis (PFGE) revealed the presence of two closely related clones confirming the horizontal spread. Measures were taken by the committee such as: strengthening the hand hygiene, patient hygiene and cohort studies of gastrointestinal colonization, which allowed the control of the outbreak.

Comunicamos un brote nosocomial por Serratia marcescens en una Unidad de Cuidados Intensivos en un hospital pediátrico de Guayaquil, Ecuador. Se detectaron nueve casos de infección, manifestándose en 55,5% de los casos como sepsis. El caso índice correspondió a un neonato derivado de otra institución con artritis séptica. La tasa de ataque fue 17,6% (n: 51) y la mortalidad 33,3%. Todos los aislados presentaron resistencia a las cefalosporinas y aminoglucósidos y sensibilidad a carbapenémicos. El análisis de clonalidad reveló la presencia de dos clones estrechamente relacionados, confirmando la diseminación horizontal. Las medidas de control de brote fueron: reforzamiento de higiene de manos, cohorte de los pacientes y búsqueda de colonización gastrointestinal.

Gene expression analysis of the SdeAB multidrug efflux pump in antibiotic-resistant clinical isolates of Serratia marcescens.

Purpose: Many isolates of Serratia marcescens, a well-known opportunistic pathogen, can be multidrug resistant. Fluoroquinolones are among the most important groups of antibiotics used for treatment of these organisms. However, fluoroquinolone resistance among S. marcescens isolates is fast increasing. Drug extrusion through efflux pumps like SdeAB/ HasF is one of the major mechanisms of resistance to fluoroquinolones. This study was carried out to analyze, through gene expression analysis of sdeB, the relative contribution of this mechanism toward fluoroquinolone resistance in clinical isolates of Serratia. Materials and Methods: Total RNA from 45 clinical isolates of S. marcescens was isolated. Quantitative real-time RT PCR was performed on the extracted RNA to study the gene expression of sdeB and was normalized to the sdeB expression in the standard strain of S. marcescens. Results: Of the 45 isolates analyzed, sdeB expression was found to be elevated in 20 isolates (44%). Of these 20 isolates, eight (40%) were fully resistant to at least one of the fluoroquinolones studied. Conversely, of the 20 isolates that over-expressed sdeB, 12 (60%) were fully sensitive to all fluoroquinolones tested. Conclusions: Drug efflux pumps are an important means of fluoroquinolone resistance among clinically important species ofSerratia. The expression of these pumps can be up-regulated in the presence of antibiotics and have the potential for changing the phenotype from sensitive to resistant, thus contributing to therapeutic failures.

A case of community-acquired Acinetobacter junii-johnsonii cellulitis / Celulitis por Acinetobacter junii-johnsonii adquirida en la comunidad: una presentación de caso

Acinetobacter skin and soft tissue infection outside of the traumatic wound setting are rare occurrences. The majority of cases occur in the presence of significant comorbilities and by Acinetobacter baumanii. Herein a case is reported of community-onset, health-care-associated, non-traumatic cellulitis caused by Acinetobacter, species junii-johnsonii with bacteremia. This is the first reported case of Acinetobacter junii-johnsonii skin and soft tissue infection. Hemorrhagic bullae might be one of the clinical features of Acinetobacter cellulitis.

La infección de piel y tejidos blandos por Acinetobacter no relacionada con trauma es una presentación inusual. La mayoría de los casos descritos presentan enfermedades concomitantes y son causados por Acinetobacter baumanii. Se describe un caso de celulitis no traumática por A. junii-johnsonii con bacteriemia, de inicio en la comunidad y asociado con el tratamiento médico. De acuerdo con nuestro conocimiento, éste sería el primer caso reportado de infección de tejidos blandos y piel por A. junii-johnsonii. La vesícula hemorrágica podría ser una característica clínica de celulitis por Acinetobacter.

Outbreak of neonatal infection by an endemic clone of Serratia marcescens / Surto de infecção neonatal a partir de clone endêmico de Serratia marcescens

INTRODUCTION: The outbreak occurred between February and June 2006 and included identification of the cases, analysis of medical records, cultures from environmental sources, resistance analyses and genotyping profile of Serratia marcescens. METHODS: The cultures were composed of 13 blood isolates, 17 rectal and hand swabs and air sampling. RESULTS: The data obtained by pulsed-field gel electrophoresis exhibited three strains that contaminated 24 patients. Systemic infection was the most common in neonates with lower weight, long periods of hospitalization, premature delivery and the use of mechanical ventilation. CONCLUSIONS: This investigation revealed the multifactorial nature of the outbreak. An endemic clone of S. marcescens was detected.

INTRODUÇÃO: O surto ocorreu entre fevereiro a junho de 2006 e incluiu identificação de casos, análise dos prontuários, culturas ambientais, análise de resistência e genotipagem dos isolados de Serratia marcescens. MÉTODOS: Os cultivos foram compostos de 13 isolados de sangue e 17 swabs de reto e mãos e amostras do ar. RESULTADOS: Os dados obtidos por eletroforese de campo pulsado evidenciaram três cepas que contaminaram 24 pacientes. Infecção sistêmica foi mais comum em neonatos com menor peso, longo tempo de internação, nascimento prematuro e uso de respiração mecânica. CONCLUSÕES: Foi evidenciada a natureza multifatorial do surto. Foi encontrado um clone endêmico de S. marcescens.

Cerebral abscess caused by Serratia marcescens in a premature neonate

BACKGROUND: Cerebral abscesses are extremely rare in neonates. Serratia marcescens is an unusual cause of sepsis and neurological spread is especially ominous. PURPOSE: To report the case of a 34-week neonate who developed this rare condition and to discuss diagnostic and therapeutic measures. CASE REPRT: A 34-week male neonate sequentially developed respiratory distress syndrome, early sepsis and necrotizing enterocolitis; later cultures revealed S. marcescens. After deterioration, a cerebral abscess became evident, which revealed S. marcescens. Clinical improvement ensued after high-dose amikacin and meropenem. CONCLUSION: Clinical signs are often non-specific. Proper diagnostic measures, neurosurgical consultation and aggressive antibiotic therapy are essential for these high-risk neonates.

INTRODUÇÃO: Abscessos cerebrais são extremamente raros em neonatos. Serratia marcescens é causadora incomum de sepse nestes pacientes e a disseminação no sistema nervoso central é grave. OBJETIVO: Relatar um prematuro de 34 semanas que desenvolveu esta condição e discutir as medidas diagnósticas e terapêuticas. RELATO DE CASO: Prematuro masculino de 34 semanas desenvolveu síndrome do desconforto respiratório, sepse neonatal e enterocolite necrotizante; hemoculturas revelaram S. marcescens. Após deterioração clínica, evidenciou-se um abscesso cerebral cuja drenagem revelou S. marcescens. Houve melhora após introdução de amicacina e meropenem. CONCLUSÃO: Os sinais clínicos são inespecíficos. Passos diagnósticos apropriados, avaliação neurocirúrgica precoce e antibioticoterapia agressiva são essenciais para estes prematuros.

Serratia marcescens: Descripción de un brote de infección intrahospitalaria / Serrtia marcesceens: description of a nosocomial outbreake

We describe a nosocomial outbreak of Serratia marcescens infections in different departaments, which occurred between May and December 2001. It involved 85 patients, 72 with clinical infections and 13 in which the strains isolated were found as colonization. The most common site was urinary tract infection. Thirty six percent of the infections were severe (including pneumonia and bacteremia), occurring in patients older than 65 years, with predisposing conditions, previous antibiotic usage, prolonged hospitalisation and invasive procedures. Global lethality was 2,8%. All the cases had genetically the same strain, so a common source of infection was thought. The environmental and water microbiological studies yielded no growth of Serratia, except for the water faucet in the Neurology ward, where the index case was detected, and probably where the epidemic originated.

Se describe un brote de infección intrahospitalaria por Serratia marcescens ocurrido entre mayo y diciembre del 2001 en el Hospital Del Salvador, comprometiendo a varios servicios clínicos. Este brote involucró 85 pacientes con 72 infecciones y 13 colonizaciones. La localización más frecuente de las infecciones fue la urinaria. El 36% de las infecciones fue grave (neumonías y bacteremias), afectando a pacientes sobre 65 años de edad, con patologías predisponentes como: hospitalización prolongada, procedimientos invasores, cirugía y uso de antimicrobianos previos. La letalidad global fue de 2,8%. Todos los casos correspondieron genéticamente a la misma cepa por lo que se planteó una probable fuente común de infección. El estudio microbiológico de las muestras ambientales y de las aguas no detectó S. marcescens, a excepción de un grifo del lavamanos del Servicio de Neurología donde se detectó el caso índice, por lo cual se puede deducir que probablemente éste fue el origen del brote epidémico.