Clinical and pathological findings of Rhodococcus equi infection in foals / Achados clínicos e patológicos da infecção por Rhodococcus equi em potros

Infection by Rhodococcus equi is considered one of the major health concerns for foals worldwide. In order to better understand the disease's clinical and pathological features, we studied twenty cases of natural infection by R. equi in foals. These cases are characterized according to their clinical and pathological findings and immunohistochemical aspects. Necropsy, histologic examination, bacterial culture, R. equi and Pneumocystis spp. immunohistochemistry were performed. The foals had a mean age of 60 days and presented respiratory signs (11/20), hyperthermia (10/20), articular swelling (6/20), prostration (4/20), locomotor impairment (3/20) and diarrhea (3/20), among others. The main lesions were of pyogranulomatous pneumonia, seen in 19 foals, accompanied or not by pyogranulomatous lymphadenitis (10/20) and pyogranulomatous and ulcerative enterocolitis (5/20). Pyogranulomatous osteomyelitis was seen in 3 foals, one of which did not have pulmonary involvement. There was lymphoplasmacytic (4/20), lymphoplasmacytic and neutrophilic (1/20) or pyogranulomatous arthritis (1/20), affecting multiple or singular joints. Immunohistochemistry revealed to be a valuable tool for the detection of R. equi, confirming the diagnosis in all cases. Furthermore, pulmonary immunostaining for Pneumocystis spp. demonstrates that a coinfection with R. equi and this fungal agent is a common event in foals, seen in 13 cases.(AU)

Infecção por Rhodococcus equi é considerado um dos maiores problemas sanitários para potros em todo o mundo. Para melhor compreender a apresentação clínica e patológica da enfermidade, foram avaliados vinte casos de infecção natural por R. equi em potros. Os casos são caracterizados de acordo com seus achados clínicos e patológicos e aspectos imuno-histoquímicos. Foram realizados exames de necropsia, histologia, bacteriologia e imuno-histoquímica para R. equi e Pneumocystis spp. Os potros tinham idade media de 60 dias e apresentaram sinais respiratórios (11/20), hipertermia (10/20), aumento de volume articular (6/20), prostração (4/20), distúrbios locomotores (3/20) e diarreia (3/20), entre outros. As lesões mais importantes eram pneumonia piogranulomatosa, vista em 19 potros, acompanhada ou não por linfadenite piogranulomatosa (10/20) e enterocolite ulcerativa (5/20). Osteomielite piogranulomatosa foi constatada em três potros, um dos quais não apresentava envolvimento pulmonar. Artrites afetando uma ou múltiplas articulações eram caracterizadas por infiltrado linfoplasmocítico (4/20), linfoplasmocítico e neutrofílico (1/20) e piogranulomatoso (1/20). A imuno-histoquímica demonstrou ser uma ferramenta valiosa na detecção de R. equi, permitindo confirmar o diagnóstico em todos os casos avaliados. Além disso, a imuno-histoquímica para Pneumocystis spp. demonstra que a coinfecção por R. equi e o agente fúngico é um evento frequente em potros, constatado em 13 casos.(AU)

Identification of pathogens and virulence profile of Rhodococcus equi and Escherichia coli strains obtained from sand of parks

The identification of pathogens of viral (Rotavirus, Coronavirus), parasitic (Toxocara spp.) and bacterial (Escherichia coli, Salmonella spp., Rhodococcus equi) origin shed in feces, and the virulence profile of R. equi and E. coli isolates were investigated in 200 samples of sand obtained from 40 parks, located in central region of state of Sao Paulo, Brazil, using different diagnostic methods. From 200 samples analyzed, 23 (11.5%) strains of R. equi were isolated. None of the R. equi isolates showed a virulent (vapA gene) or intermediately virulent (vapB gene) profiles. Sixty-three (31.5%) strains of E. coli were identified. The following genes encoding virulence factors were identified in E. coli: eae, bfp, saa, iucD, papGI, sfa and hly. Phylogenetic classification showed that 63 E. coli isolates belonged to groups B1 (52.4%), A (25.4%) and B2 (22.2%). No E. coli serotype O157:H7 was identified. Eggs of Toxocara sp. were found in three parks and genetic material of bovine Coronavirus was identified in one sample of one park. No Salmonella spp. and Rotavirus isolates were identified in the samples of sand. The presence of R. equi, Toxocara sp, bovine Coronavirus and virulent E. coli isolates in the environment of parks indicates that the sanitary conditions of the sand should be improved in order to reduce the risks of fecal transmission of pathogens of zoonotic potential to humans in these places.

Phenotypic and genotypic characterization of Rhodococcus equi isolated from sputum

INTRODUCTION: Rhodococcus equi is an opportunistic pathogen, causing rhodococcosis, a condition that can be confused with tuberculosis. Often, without identifying M. tuberculosis, physicians initiate empiric treatment for tuberculosis. R. equi and M. tuberculosis have different susceptibility to drugs. Identification of R. equi is based on a variety of phenotypic, chromatographic, and genotypic characteristics. OBJECTIVE: This study aimed to characterize bacterial isolates from sputum samples suggestive of R. equi. METHODS: The phenotypic identification included biochemical assays; thin-layer chromatography (TLC) and polymerase chain reaction (PCR) were used for genotypic identification. RESULTS: Among 78 Gram-positive and partially acid-fast bacilli isolated from the sputum of tuberculosis-suspected patients, 51 were phenotypically and genotypically characterized as R. equi based on literature data. Mycolic acid analysis showed that all suspected R. equi had compounds with a retention factor (Rf) between 0.4-0.5. Genotypic characterization indicated the presence of the choE gene 959 bp fragments in 51 isolates CAMP test positive. Twenty-two CAMP test negative isolates were negative for the choE gene. Five isolates presumptively identified as R. equi, CAMP test positive, were choE gene negative, and probably belonged to other bacterial species. CONCLUSIONS: The phenotypic and molecular techniques used constitute a good methodological tool to identify R. equi.

Rhodococcus equi en paciente VIH/sida: primera detección molecular en Cuba / First molecular detection of Rhodococcus equi in a HIV/aids patient in Cuba

Introducción: Rhodococcus equi es reconocido como un patógeno emergente que causa importante morbilidad y mortalidad entre los pacientes inmunocomprometidos. Objetivo: confirmar la presencia de R. equi en líquido pleural mediante la técnica del polimorfismo en la longitud de los fragmentos de restricción. Métodos: se empleó muestra de líquido pleural de un paciente sida con síntomas respiratorios. Se realizaron cultivos microbiológicos, pruebas de tinción, fenotípicas, bioquímicas y la técnica del polimorfismo en la longitud de los fragmentos de restricción para el diagnóstico del microorganismo. Resultados: las técnicas de tinción, fenotípicas y bioquímicas brindaron un diagnóstico sugestivo de infección por R. equi, el cual fue confirmado por las técnicas moleculares utilizadas. Conclusiones: este trabajo reporta la detección molecular, por primera vez en Cuba, de R. equi en paciente VIH/sida. Los resultados obtenidos permiten sugerir que técnicas de biología molecular pueden ser aplicadas en el diagnóstico y la identificación de R. equi.

Introduction: Rhodococcus equi is recognized as an emerging pathogen that causes important morbidity and mortality among immunocompromised patients. Objective: to confirm the presence of R. equi in pleural fluid through the restriction fragment length polymorphism technique. Methods: the pleural fluid sample from one AIDS patient with respiratory symptoms was used. Microbiologic culture, staining tests, phenotypic and biochemical tests and restriction fragment length polymorphism technique for the diagnosis of microorganism were performed. Results: the staining technique along with the phenotypic and biochemical tests provided the presumptive diagnosis of R. equi infection, which was further confirmed by the molecular techniques. Conclusions: this paper reported the molecular detection of R. equi from one HIV/aids patient for the first time in Cuba. The results suggested that the molecular biology techniques could be used in the diagnosis and identification of R. equi.

Rhodococcus equi infection after reduction mammaplasty in an immunocompetent patient / Infección por Rhodococcus equi luego de cirugía de reducción mamaria en huésped inmunocompetente

The majority of infections caused by R. equi occur in hosts with some degree of cell-mediated immunodeficiency. Immunocompetent individuals are infrequently affected and usually present with localized disease. Infections of the skin or related structures are uncommon and are usually related to environmental contamination. The microbiology laboratory plays a key role in the identification of the organism since it may be mistaken for common skin flora. We describe a 31 year-old woman without medical problems who presented nine weeks after breast reduction with right breast cellulitis and purulent drainage from the surgical wound. She underwent incision and drainage, and cultures of the wound yielded Rhodococcus equi. The patient completed six weeks of antimicrobial therapy with moxifloxacin and rifampin with complete resolution.

La mayoría de las infecciones causadas por Rhodococcus equi ocurren en huéspedes con algún grado de inmunodeficiencia celular. Los individuos inmunocompetentes son afectados con baja frecuencia y suelen presentarse con enfermedad localizada. Las infecciones de la piel o partes blandas son poco frecuentes y están usualmente relacionadas con contaminación ambiental. El laboratorio de microbiología juega un papel clave en la identificación del organismo, ya que este puede confundirse con flora normal de la piel. Se describe una mujer de 31 años sin problemas médicos que consultó nueve semanas después de haber sido sometida a cirugía de reducción mamaria, con celulitis del seno derecho y drenaje purulento de la herida quirúrgica. Se practicó incisión y drenaje quirúrgico y los cultivos de la herida demostraron R. equi. La paciente recibió seis semanas de tratamiento antimicrobiano con moxifloxacina y rifampicina demostrando resolución completa.

Bacteremia due to Rhodococcus equi in an immunocompetent infant.

Rhodococcus equi , previously known as Corynebacterium equi, is one of the most important causes of zoonotic infection in grazing animals. Increased cases of human infection with R. equi have been reported especially in immunocompromised patients. Infection in immunocompetent patients is extremely rare. We report a case of R. equi bacteremia in a 26-day-old immunocompetent infant with recurrent swellings on different parts of the body. To the best of our knowledge, this is the first ever report of R. equi bacteremia from an immunocompetent patient from Northern India.

Rhodococcus equi isolation from sputum of patients with suspected tuberculosis

Rhodococcus equi has emerged as an opportunistic pathogen associated with pulmonary, invasive or systemic infections in immunocompromised patients. We report the identification of 51 R. equi isolates found in sputum samples of 546 individuals suspected to have pulmonary tuberculosis in two Public Health Hospital Units in Brazil. The epidemiology of R. equi infection as well as the phenotypic identification and drug susceptibility profile of isolates are described in this paper.

Molecular characterization of Rhodococcus equi isolates of horse breeding farms from an endemic region in South of Brazil by multiplex PCR

Rhodococcus equi is a gram-positive coco-bacillus and an intracellular opportunistic pathogen which causes pneumonia in foals. It is widely detected in environment and has been isolated from several sources, as soil, feces and gut from health and sick foals. The goal of this study was to characterize the epidemiological status (endemic, sporadic or no infection) of horse breeding farms from Bage County in South of Brazil, using a multiplex PCR. One hundred and eighteen R. equi isolates were identified by biochemical tests and submitted to a specie-specific and vapA multiplex PCR. These isolates were obtained from: three farms where the R. equi infection has been noticed, two farms where the disease has been not reported and one farm where the disease is frequent. All clinical isolates from horse breeding farms where the disease is endemic and/or sporadic were vapA-positive. None environmental isolates were vapA-positive. In three horse breeding farms with sporadic R. equi infection, 11.54 percent of the isolates from adult horse feces were vapA-positive. The multiplex PCR technique has proven to be effective for the molecular and epidemiological characterization of the R. equi isolates in horse breeding farms. An important finding in this study was the isolation of vapA-positive R. equi from adult horse feces, which is an evidence for other routes of dissemination of this pathogen in the farms.

Rhodococcus equi é um coco-bacilo gram positivo que causa pneumonia em potros. Trata-se de um patógeno oportunista amplamente detectado no ambiente e isolado de várias fontes, como solo, fezes e intestino de potros doentes e sadios. O presente estudo visa caracterizar a situação epidemiológica de criatórios eqüinos da região de Bagé, RS, Brasil, pela técnica de PCR multiplex. Cento e dezoito isolados de R. equi foram identificados por testes bioquímicos e, posteriormente, submetidos a um PCR multiplex para caracterização da espécie e da presença do gene vapA. Estes isolados eram provenientes de três haras com histórico da doença, dois haras onde não havia casos da doença e uma propriedade onde a infecção por R. equi é relatada frequentemente. Todos os isolados clínicos provenientes de haras onde a doença é endêmica e/ou esporádica foram vapA positivos. Nenhum isolado ambiental foi vapA positivo. Nos três haras onde a doença é esporádica, 11,54 por cento dos isolados de fezes de eqüinos adultos foram positivos para o gene vapA. A técnica de PCR multiplex mostrou-se efetiva para caracterização epidemiológica e molecular dos criatórios equinos, estando de acordo com o histórico da propriedade. Um fato relevante demonstrado pela aplicação desta técnica foi a detecção de R. equi vapA positivo nas fezes de eqüinos adultos. Esta observação pode pressupor que haja outras vias de disseminação da bactéria dentro de uma propriedade.

Minimal inhibitory concentration of azithromycin in Rhodococcus equi strains isolated from foals

O perfil de sensibilidade microbiana e a concentração inibitória mínima (MIC) da azitromicina para 42 cepas de Rhodococcus equi isoladas de potros, no Brasil, e em uma cepa-controle, foi avaliado, respectivamente, pelos métodos de difusão com discos e E-test. A azitromicina apresentou 100 por cento de efetividade in vitro para todas as cepas em ambos os testes. As cepas de R. equi apresentaram MIC90 para azitromicina em valores <1.5µg/ml. Este estudo mostra a alta efetividade da azitromicina em linhagens de R. equi isoladas no Brasil, sugerindo o uso dessa droga como alternativa na terapia da rodococose em potros.

Bacteremia por Rhodococcus equi em paciente com síndrome da imunodeficiência adquirida: relato de caso / Bacteremia due to Rhodococcus equi in a patient with acquired immunodeficiency syndrome: case report

Rhodococcus equi é um importante agente de infecções zoonóticas, podendo causar sérias infecções em humanos, principalmente em pacientes imunocomprometidos. Neste estudo, nós relatamos o caso de uma bacteremia fatal devido a Rhodococcus equi em paciente com síndrome da imunodeficiência adquirida (HIV positivo).

Rhodococcus equi is an important agent for zoonotic infections, and may cause serious infections in humans, especially immunocompromised patients. In this study, a case of fatal bacteremia due to Rhodococcus equi in a patient with acquired immunodeficiency syndrome (HIV positive) is reported.

Pathogenicity of Rhodococcus equi in mice, isolated from environment, human and horse clinical samples

Rhodococcus equi is a facultative intracellular pathogen associated with bronchopneumonia, mesenteric lymphadenitis and enterocolitis in foals. Although R. equi is likely to be found in every horse-breeding farm, the clinical disease is unrecognized in most of them. Capsule components, equi factor, micolic acid and some products encoded by the large 85-90Kb plasmid were described as virulence factors. However, the pathogenesis of R. equi infections and the sensibility of foals are not completely understood. The aim of this study was evaluate the virulence of R. equi isolated from human, horses and environment for mices. Nine strains carrying the 85-90Kb plasmid isolated from foal clinical specimens, one from immunodeficient human patient and six plasmidless strains (four isolated from feces, one from pasture and one from immunodeficient human patient) were inoculated in cyclophosphamide immunossuppressed mice. The pathological changes and viability of R. equi cells in the liver of mice was verified after the 3rd, 6th an 10th day after inoculation for horse and environmental isolates and for R. equi isolates from human patients on the 1st, 3rd and 6th day. During the necropsy procedures, infiltrate of macrophages and pyogranulomatous lesions were detected after the sixth pos-inoculation day in the liver and spleen. In horse isolates, only plasmid positive strains were virulent, but in human isolates both strains (plasmid positive e plasmid negative) were virulent. Both groups of the immunossupressed mice inoculated with R. equi isolated from environment showed pathological changes. All R. equi strains were unable to kill non imunossuppressed mice.

Rhodococ-cus equi é um patógeno intracelular facultativo associado com broncopneumonia, linfadenite mesentérica e enterocolite em potros. Apesar do patógeno ser amplamente distribuído no ambiente equino, a doença não é encontrada em todos os criatórios. Componentes capsulares, "fator equi", ácido micólico e alguns produtos codificados por um grande plasmídeo de 85-90Kb foram descritos como fatores de virulência. Entretanto, a patogênese da infecção e a susceptibilidade dos potros não são completamente entendidas. Nove cepas carreando o plasmídeo e isoladas de potros doentes, um isolado de paciente humano imunossuprimido, e seis cepas sem plasmídeo (4 de fezes, 1 de pastagem e 1 de paciente humano imunossuprimido) foram inoculadas em camundongos imunossuprimidos com ciclofosfamida. As alterações patológicas e a viabilidade das células de R. equi no fígado foram verificadas depois do terceiro, sexto e décimo dia após a inoculação para isolados clínicos e depois do primeiro, terceiro e sexto dia para isolados de pacientes humanos. Na necropsia foram detectados infiltrado de macrófagos e lesões piogranulomatosas no fígado e baço dos camundongos após o sexto dia da inoculação. Para isolados clínicos, somente os plasmídeo positivos foram virulentos, mas para os humanos, ambos os isolados (plasmídeo positivos e plasmídeo negativos) foram virulentos. Ambos os grupos de camundongos imunossuprimidos inoculados com isolados ambientais mostraram alterações patológicas. Todos os isolados foram incapazes de matar camundongos imunocompe-tentes.

Neumonía cavitada por Rhodococcus equi en paciente inmunocomprometido no infectado por virus de inmunodeficiencia humana: Caso clínico y revisión / Necrotizing pneumonia due to Rhodococcus equi in non HIV immunocompromised host: Case report and review

Rhodococcus equi, es un bacilo grampositivo intracelular que causa infecciones mayoritariamente en pacientes inmunodeprimidos. Reportamos el caso de una mujer de 52 años, en tratamiento de lupus eritematoso sistémico, con historia progresiva de 10 meses de evolución caracterizada por tos, disnea progresiva, expectoración muco-purulenta, ocasionalmente hemoptoica, fiebre intermitente, y pérdida de peso del 10 por ciento. Tuvo respuesta parcial a diversos cursos de tratamiento antimicrobiano y el seguimiento radiológico evidenció la aparición de múltiples focos de consolidación bilaterales, algunos de ellos nodulares. El estudio microbiológico de un lavado broncoalveolar y de una biopsia pulmonar percutánea permitió la identificación de R. equi y la histología de la biopsia pulmonar fue compatible. Recibió tratamiento antimicrobiano bi-asociado prolongado con buena respuesta clínica y radiológica. Se debe considerar este agente en el estudio de pacientes inmunocomprometidos que cursan con neumonías de evolución prolongada.

Bacteremia due to Rhodococcus equi--a case report.

Rhodococcus equi (R. equi) primarily causes zoonotic infections affecting grazing animals and is an unusual cause of infection in immunocompetent human beings. We report a case of bacteremia due to R. equi a rare isolate in a child suffering from protein energy malnutrition

Primer aislamiento clínico de Rhodococcus equi en Costa Rica / First isolation clinics of Rhodococcus equi in Costa Rica

Se reporta el primer aislamiento de Rhodococcus equi en nuestro país. Se trata de una niña que después de nacer en el Hospital San Juan de Dios fue trasladada al Servicio de Neonatología del Hospital Nacional de Niños con diagnóstico de neumonía severa. De hemocultivo se aisló un bacilo Gram positivo cuyas características morfológicas y bioquímicas permitieron clasificarlo como Rhodococcus equi. Se comentan detalles de su clasificación, su comportamiento ante los antimicrobianos y la rápida evolución clínica hacia la muerte de la niña. Se hace revisión de literatura

Uncommon manifestations of opportunistic infections in an HIV infected patient.

A case of an HIV infected patient complicated with Penicillium marneffei and Rhodococcus equi infection is reported. He presented with chronic ulcer as pyoderma gangrenosum-like on his right calf and submandibular lymphadenitis as scrofuloderma-like. Penicillium marneffei and Rhodococcus equi were isolated from the ulcer and lymph node respectively.

Aspectos epidemiológicos do Rhodococcus equi em eqüinos do Município de Bagé, RS, Brasil / Epidemiological aspects of Rhodococcus equi in horses from Bagé county, RS, Brazil

Este trabalho foi realizado com o intuito de obter informaçoes epidemiológicas sobre o Rhodococcus equi (R.equi) em seis haras do município de Bagé, estado do Rio Grande do Sul. Foram coletadas 36 amostras de solo superficial e 143 de fezes de eqüinos, sendo semeados em meio seletivo para o R. equi(NANAT) e incubadas em aerobiose a 37 graus por até 72 horas. Também foi coletada amostra de solo para determinaçao de pH e matéria orgânica (MO) de cada haras. A identificaçao do R. equi baseou-se na pesquisa do ®fator equi¼ e características morfológicas, tintoriais e bioquímicas. Isolou-se o microrganismo de 75 porcento (27/36) das amostras de solo superficial e 66,43 porcento (95/143) das amostras de fezes de eqüinos. O isolamento o R. equi em 100 porcento dos haras analisados comprova a disseminaçao desta bactéria na regiao estudada. Os dados obtidos na análise de pH e MO do solo nao demonstraram correlaçao com a taxa de isolamento do R. equi do solo superficial dos haras.

Steroid transformation with immobilized locally isolated Corynebacterium equi cells

The locally isolated Corynebacterium equi cells were immobilized by entrapment in calcium alginate beads. The transformation yield of cortisol to prednisolone by the immobilized cells was about 8% higher than obtained with free cell culture. Optimization of the immobilization process was investigated. Addition of 1.5% beta- cyclodextrin had positively affected the dehydrogenation reaction. The immobilized calcium alginate beads could be used for five repeated fermentation cycles

1-Dehydrogenation of cortisol with bacteria II- Some aspects of the enzymic 1-Dehydrogenation of cortisol with Corynebacterium equi

The enzymatic delta 1- dehydrogenation of cortisol to prednisolone with C. equi under varient conditions was evaluated. Mg+2 and K encouraged the formation of high yields of prednisolone while Mn+2 gave comparatively lower product yield. Supplementation of the transformation medium with fumarate, citrate and oxalate markedly enhanced the formation of prednisolone. Among the vitamins tested, menadione and riboflavine led to the formation of high yields of prednisolone. Higher conversion estimates were observed when cortisol was mixed with Tween 40

Delta 1-Dehydrogenation of cortisol with bacteria III- Some biochemical aspects of delta 1 dehydrogenation of cortisol with Corynebacterium equi

The enzymic transformation of cortisol with Corynebacterium equi was examined in the presence of some biological bases, redox agents, enzyme inhibitors and steroid inducers. Supplementation of the reaction mixture with adenine and adenosine retarded the formation of prednisolone, while uracil and xanthine led to the formation of high yields of prednisolone. The enzymic delta 1-dehydrogenation reaction of cortisol was accelerated in the presence of oxidized glutathione. The bioconversion of cortisol to predniso[lone, was also activated in the presence of azide and cyanide. With iodoacetate, the delta 1-Dehydrogenation reaction was promoted. The delta 1-Dehydrogenation reaction of cortisol was considerably induced when the cells, were pretreated with delta 1 Dehydroprogesterone, and delta 1-dehydrotestosterone