Bacteremia and sepsis by Arcanobacterium haemolyticum in a young immunocompetent patient / Bacteriemia y sepsis por Arcanobacterium haemolyticum en un paciente joven inmunocompetente

Abstract We report the case of a twenty-year-old immunocompetent male patient presenting to the emergency room with pharyngitis and fever. Blood cultures were drawn and Arcanobacterium haemolyticum (rough biotype) was recovered. The presence of the arcanolysin gene was investigated at the molecular level and the upstream region was amplified and sequenced in order to correlate it with the smooth or rough biotype. Although the isolate was susceptible to penicillin, vancomycin and gentamicin, empirical treatments first with amoxicillin/clavulanic acid (1g/12h) and then with ceftriaxone (1g/12h) failed and the infection evolved to sepsis. Finally, treatment with vancomycin (1 g/12 h) plus piperacillin/tazobactam (4.5g/8h) was effective. Lemierre's syndrome was ruled out. To the best of our knowledge, this is the first case of bacteremia by A. haemolyticum reported in Argentina.

Resumen Se describe el caso de un paciente varón inmunocompetente de veinte anos de edad que se presentó en la sala de emergencias con faringitis y fiebre. Se extrajeron muestras para realizar hemocultivos y se recuperó Arcanobacterium haemolyticum (biotipo rugoso). Se investigó la presencia del gen de la arcanolisina por un método molecular, y se amplificó y Faringitis; secuenció la región upstream de dicho gen para determinar su correlación con los biotipos lisos Bacteriemia; o rugosos. Aunque el aislamiento fue sensible a la penicilina, la vancomicina y la gentamicina, Sepsis; los tratamientos empíricos primero con amoxicilina/ácido clavulánico (1 g/12 h) y luego con Síndrome de Lemierre ceftriaxona (1 g/12 h) no fueron efectivos, y la infección evolucionó a sepsis. Finalmente, el tratamiento con vancomicina (1 g/12 h) más piperacilina/tazobactam (4,5g/8h) fue efectivo. Se descartó la presencia del síndrome de Lemierre. Según nuestro conocimiento, este es el primer caso de bacteriemia por A. haemolyticum reportado en Argentina.

Rhodococcus equi, primer reporte de un caso de enfermedad diseminada en el Perú / Rhodococcus equi, first case report of disseminated disease in Peru

Resumen Presentamos el caso de un paciente con infección por virus de inmunodeficiencia humana (VIH) con recuento de LTCD4+ 49 céls/mm3, que consultó por un cuadro de siete meses de baja de peso, dolor abdominal, diarrea crónica y lesiones cutáneas gomosas. El mielocultivo y hemocultivos fueron positivos para Rhodococcus equi. Además, se observaron lesiones histológicas en piel e intestino compatibles con este agente como malacoplaquia, reacción granulomatosa y cuerpos de Michaelis-Gutmann. Se descartó compromiso pulmonar mediante tomografía de tórax. Recibió terapia antibacteriana combinada con claritromicina, imipenem y vancomicina. A pesar del tratamiento, el paciente evolucionó desfavorablemente y falleció.

Abstract We present the case of a patient with human immunodeficiency virus (HIV) with a LTCD4 + 49 cells/mm3, who was admitted due to a seven-month period of weight loss, abdominal pain, chronic diarrhea and rubbery skin lesions. Myeloculture and blood cultures were positive for Rhodococcus equi. In addition, histological lesions in the skin and intestine compatible with this agent were observed, such as malacoplachy, granulomatous reaction and Michaelis-Gutmann bodies. Pulmonary involvement was ruled out by chest tomography. The patient received antibacterial therapy combined with clarithromycin, imipenem, and vancomycin. Despite the treatment, the patient evolved unfavorably and died.

Rhodococcus equi como causa de neumonía en el síndrome de inmunodeficiencia adquirida / Rhodococcus equi as a cause of pneumonia in the acquired immunodeficiency syndrome

RESUMEN Rhodococcus equi es un microorganismo emergente asociado a infecciones oportunistas en individuos inmunocomprometidos, especialmente en pacientes con infección por virus de inmunodeficiencia humana. Se desarrolló una búsqueda en la Biblioteca Virtual de Infomed, fueron revisados 215 trabajos científicos sin limitación de año y país, seleccionándose 55. El rhodococcus es un patógeno intracelular capaz de crecer y persistir dentro de los macrófagos que expresan en su superficie el receptor Mac-1 (CD11b/CC18), y posteriormente destruirlos. La manifestación clínica más frecuente es la neumonía de comienzo insidioso y en su evolución natural tiende a la cavitación. El diagnóstico se realiza mediante su identificación en cultivo de muestras de tejido afectado. Los hemocultivos son positivos en el 50% de los inmunodeprimidos En el diagnóstico radiográfico, los hallazgos más comunes referidos en la literatura científica son el compromiso lobar y la cavitación. La particular evolución que experimentan los pacientes con síndrome de inmunodeficiencia adquirida y neumonía por R. equi, obliga a implementar esquemas terapéuticos basados en antimicrobianos con actividad bactericida intracelular, administrados inicialmente por vía intravenosa y durante un tiempo prolongado e incluso la cirugía. La infección por R. equi es una complicación infrecuente en pacientes con síndrome de inmunodeficiencia adquirida, pero con una elevada tasa de letalidad, por lo que debe ser sospechado en pacientes que presenten una infección respiratoria de curso inhabitual. El diagnóstico precoz, el tratamiento antimicrobiano combinado y prolongado y el inicio de la Terapia Antiretroviral de Gran Actividad en forma temprana pueden mejorar la evolución y el pronóstico de estos pacientes.

ABSTRACT Rhodococcus equi is an emergent microorganism associated to opportunistic infections in immune-compromised individuals, especially in patients infected with the human immunodeficiency virus. A search was carried out in the Virtual Library of Infomed; 215 scientific works were reviewed without limits of publication years and countries. From them, 55 were chosen. Rhodococcus equi is an intracellular pathogen that is able to grow and live inside the macrophages expressing the Mac-1 (CD11b/CC18) receptor in the surface and destroying them later. The most common clinical manifestation is insidious beginning pneumonia, tending to cavitation in its natural evolution. The diagnosis is made through identification in culture of affected tissues samples. Blood cultures are positive in 50 % of the immune-depressed people. At the radiographic diagnosis, the most common findings referred to in the scientific literature are lobar compromise and cavitation. The particular evolution of the patients with acquired immune-deficiency syndrome and pneumonia due to Rhodococcus equi forces the implementation of therapeutic schemes based on antimicrobials with intracellular bactericide activity, administered firstly intravenously and during a long time, and even to perform the surgery. Rhodococcus equi infection is an infrequent complication in patients with acquired immunodeficiency syndrome, but having a high lethality rate, therefore it should be suspected in patients presenting a respiratory infection of unusual curse. The precocious diagnosis, combined and prolonged antimicrobial treatment and early beginning of the highly active antiretroviral therapy could improve the evolution and prognosis of these patients.

Infección por Rhodococcus equi en pacientes con SIDA: Análisis retrospectivo de 13 pacientes en Argentina / Rhodococcus equi infection in AIDS patients: Retrospective analysis of 13 patients in Argentina

Introduction: Rhodococcus equi is a gram positive coccoid rod that causes pulmonary infections in immunosuppressed patients. Methods: We retrospectively analyzed epidemiological, clinical, microbiological, radiological, and immunological features as well as the outcomes of 13 AIDS patients with R. equi infection. Results: Between January 1994 and December 2012, 13 patients attending the AIDS department of the Infectious Diseases reference hospital in Buenos Aires were diagnosed with R. equi infection. All were men, the median age was 27 years. At the time of diagnosis, the median of CD4+ T cell counts was 11 cells/μl Twelve patients presented pulmonary disease with isolation of the microorganism from sputum or bronchoalveolar lavage; in the other patient the diagnosis was postmortem with positive culture of cerebrospinal fluid. The most frequent clinical manifestations were fever, haemoptysis, and weight loss. The predominant radiological finding was lobe consolidation with cavitation. Nine patients died after a median survival of 5.5 months. In all of them, cultures persisted positive until the last admission. The other 4 patients did continue clinical follow-ups. Conclusion: The insidious course of R. equi disease and the difficulties in the isolation of the microorganism contribute to the delay in the diagnosis and to the high mortality rate of this opportunistic infection.

Introducción: Rhodococcus equi es un cocobacilo grampositivo que provoca compromiso pulmonar en pacientes inmunodeprimidos. Métodos: En el presente trabajo se analizaron de manera retrospectiva los hallazgos epidemiológicos, clínicos, microbiológicos, imagenológicos, inmunológicos y la evolución de 13 pacientes con SIDA y enfermedad por R. equi. Resultados: Entre enero de 1994 y diciembre de 2012, 13 pacientes internados en la División de VIH/SIDA del hospital de referencia para Enfermedades Infecciosas de la ciudad de Buenos Aires egresaron con diagnóstico de enfermedad por R. equi. Todos eran varones y la mediana de edad fue 27 años. La mediana de linfocitos T CD4+ fue de 11 céls/μl Doce pacientes presentaron enfermedad pulmonar con aislamiento del microorganismo del esputo o del lavado bronco-alveolar; en el restante se recibió post mortem el cultivo positivo de líquido cefalorraquídeo. Las manifestaciones clínicas más frecuentes fueron fiebre, hemoptisis y pérdida de peso. La imagen radiológica predominante fue la consolidación con cavitación. Nueve pacientes fallecieron, con una mediana de supervivencia de 5,5 meses. En todos ellos el cultivo persistió positivo hasta la última internación. Los cuatro restantes abandonaron los controles y no pudieron ser evaluados en el tiempo. Conclusión: El curso insidioso de la enfermedad por R. equi y las dificultades en la identificación del microorganismo, contribuyen al retardo en el diagnóstico y a la elevada mortalidad de esta infección oportunista en esta población de pacientes.

Development of a real-time SYBR Green PCR assay for the rapid detection of Dermatophilus congolensis

Methods such as real time (RT)-PCR have not been developed for the rapid detection and diagnosis of Dermatophilus (D.) congolensis infection. In the present study, a D. congolensis-specific SYBR Green RT-PCR assay was evaluated. The detection limit of the RT-PCR assay was 1 pg of DNA per PCR reaction. No cross-reaction with nucleic acids extracted from Pseudomonas aeruginosa, Mycobacterium tuberculosis, Staphylococcus aureus, or Austwickia chelonae was observed. Finally, the RT-PCR assay was used to evaluate clinical samples collected from naturally infected animals with D. congolensis. The results showed that this assay is a fast and reliable method for diagnosing dermatophilosis.

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.

Neumonía por Rhodococcus equi: hallazgos clínico-radiológicos en ocho pacientes con sida / Pneumonia caused by Rhodococcus equi: clinical and radiological findings in 8 AIDS patients

INTRODUCIÓN: el Rhodococcus equi, es una bacteria que pertenece al orden de los Actinomicetales. Su presentación en el hombre es poco frecuente. Es con la epidemia del VIH/sida que se han ido incrementando los casos. En los humanos el órgano principal de esta infección es el pulmón, provoca una neumonía que se caracteriza por una evolución clínica y radiológica lenta. OBJETIVO: describir las alteraciones radiográficas iniciales causadas por la infección por R. equi en 8 pacientes con sida, su evolución radiológica y la presentación clínica e inmunológica. MÉTODOS: se realizó un estudio retrospectivo descriptivo de las imágenes radiológicas pulmonares observadas en el período entre agosto de 1994 y enero de 2008 en pacientes con síndrome de inmunodeficiencia humana adquirida (sida) e infección respiratoria causada por Rhodococcus equi. RESULTADOS: el cuadro clínico se caracterizó por la fiebre elevada hasta 39 °C, tos con expectoración y disnea. La presentación radiológica más frecuente fue la opacidad homogénea en 62,5 por ciento de los casos, predominó la afectación pulmonar en los lóbulos inferiores. La evolución radiológica se caracterizó por la opacidad con cavitación en su interior en 4 casos, fibrosis en 4 casos y 1 tuvo resolución total de las lesiones. El conteo de linfocitos T CD4 + estuvo disminuido en los 8 pacientes. La evolución de los pacientes osciló entre los 2 y 33 meses. CONCLUSIONES: el diagnóstico de neumonía por R. equi debe ser considerado, en aquellos pacientes portadores de VIH/sida con estado inmunológico comprometido y proceso respiratorio con manifestación radiológica de consolidación pulmonar con evolución hacia la cavitación, con evolución clínica y radiológica tórpida y prolongada.

INTRODUCTION: the Rhodococcus equi is one bacterium of the order Actinomycetales. It rarely appears in humans, but the HIV/AIDS epidemic has increased the number of cases and the main affected organ is the lung. It causes pneumonia characterized by a slow clinical and radiological progression. OBJECTIVE: to describe the initial radiological alterations from R. equi infection in 8 AIDS patients, the radiological evolution and the clinical and immunological presentation. METHODS: a retrospective descriptive study of radiological pulmonary images from AIDS patients with respiratory infection due to Rhodococcus equi was conducted. RESULTS: these patients presented with high fever (39ºC), cough with expectoration and shortness of breath. Homogeneous opacity was the most frequent radiological presentation (62,5 percent of cases), located predominantly in the lower lobules. The radiological evolution was characterized by opacity with inner cavitation in 4 cases, fibrosis in 4 cases, and one case showed total recovery of lesions. The CD4+ T-cell count was low in all the patients. The evolution ranged from 2 to 33 months. CONCLUSIONS: the R equi pneumonia diagnosis should be borne in mind when dealing with HIV/AIDS patients with compromised immunological condition and breathing process with radiological manifestation of pulmonary consolidation evolving into cavitation, and torpid and prolonged clinical and radiological evolution.

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.

A Case of Catheter-Related Bacteremia of Tsukamurella pulmonis / 대한진단검사의학회지

Tsukamurella pulmonis is an aerobic actinomycete. We report a catheter-related bacteremia of T. pulmonis. A 39 yr-old male with ALL was hospitalized to receive bone marrow transplantation (BMT). Although the patient developed a high fever at the 7th hospital day (HD), it subsided with vancomycin treatment, and he received BMT at 9th HD. Fever resurged at 16th HD despite sustained treatment with vancomycin, meropenem, and amphotericin B, but subsided with removal of Hickman catheter (HC) at 19th HD. Three sets of blood cultures comprising one from the HC and two from venipunctures were taken at 7th, 16th, and 19th HD, and the distal tip of the HC was also cultured. The aerobic vials of all 3 HC-withdrawn blood cultures and one peripheral blood culture taken at 19HD and the HC tip culture grew long, straight, thin gram-positive rods that were positive on modified Kinyoun stain. This organism showed tiny, rough, grey colonies after 3-day incubation and grew to large flat colonies when incubation was extended. It was catalase-positive, urease-positive, and alkaline-slant/alkaline-deep on triple sugar iron agar, and hydrolyzed hypoxanthine. The sequence of 1,296 base pairs of 16S rRNA of this organism showed a 100.0% homology with the published sequence of T. pulmonis DSM 44142T. To our knowledge, this is the first report of T. pulmonis bacteremia in Korea.

A Case of Necrotizing Fasciitis Due to Streptococcus agalactiae, Arcanobacterium haemolyticum, and Finegoldia magna in a Dog-bitten Patient with Diabetes / 대한진단검사의학회지

We report a case of necrotizing fasciitis involving Streptococcus agalactiae, Arcanobacterium haemolyticum, and Finegoldia magna in a 36-yr-old female diabetic patient, which started after a minor dog bite to the toe of the patient. This case suggested that a trivial infection after a minor dog bite in an immunocompromised patient such as diabetes patient could result in a significant complication such as necrotizing fasciitis. The life-threatening infection was cured by timely above-the-knee amputation, as well as penicillin G and clindamycin therapy.

Prevalência de gardnerella e mobiluncus em exames de colpocitologia em Tomé-Açu, Pará / Prevalence of gardnerella and mobiluncus in vaginal cytology examinations in Tome-Açu-Pará

Objetivo: a Gardnerella vaginalis, isoladamente ou associada ao Mobiluncus sp., é um dos principais agentes causadores de infecções em mulheres em idade reprodutiva, seja pela falta de hábitos de higiene adequados, número de parceiros sexuais ou desequilíbrios da microflora vaginal. Assim, buscou-se verificar a prevalência de G vaginalis e/ou Mobiluncus sp., associadas às condições sócio-culturais em mulheres atendidas no Hospital de Quatro Bocas de Tomé-Açu - Pará, através de exame preventivo de câncer de colo do útero. Método e Resultados: analisados materiais cervico-vaginais e informações sócio-culturais de 156 mulheres, com faixas etárias de 17 e 73 anos, período de outubro de 2003 a julho de 2004, para o diagnóstico de prevenção de câncer ginecológico. Todas as amostras foram processadas de modo convencional e analisadas no Laboratório de Citopatologia da Universidade Federal do Pará por três observadores (estudo cego). Como resultados verificou-se que das 156 mulheres pesquisadas , a maior prevalência estava associada à G vaginalis (48,15%), faixa etária de 21 a 30 anos, ou pela associação G vaginalis e Mobiluncus sp (36,36%). Em relação ao grau de escolaridade e ocupação, a maior prevalência ocorreu em mulheres com r grau incompleto (47,37%), com atividades do lar (21,05%) e comércio (22,81%). Conclusões: estes dados reforçam pesquisas que relacionam a prevalência de G vaginalis e/ou Mobiluncus sp, em mulheres com vida sexual e menor grau de escolaridade.

Objective: gardnerella vaginalis, alone or associated to Mobiluncus sp., is one of the main etiological agents ofinfection in women of reproductive age, due to lack of appropriate hygiene habits, number of sexual partners ar imbalance of the vaginal microbiota. Therefore, our objective was to assess the prevalence of bacterial vaginosis caused by G vaginalis and/or Mobiluncus sp., and associate this to the sociocultural conditions in women attended ai Hospital de Quatro Bocas in Tomé-Açu - Pará - Brazil, through gynecological cancer screening. Methods and Results: cervico-vaginal smears and socio-cultural information of 156 women aged 17 to 73 were analyzedfor diagnosis and prevention of gynecological cancer from October 2003 to July 2004. Ali samples were processed in the conventional way and analyzed at Universidade Federal do Pará's Laboratory of Cytopathology by three observers (a blind study). Among ali 156 women, the largest prevalence was associated to G vaginalis (48,15%) in 21 to 30- year-old women, ar to the association of G vaginalis and Mobiluncus sp (36,36%). As for the occupation and instruction degree, the infection was most prevalent in women with incomplete primary school (47,37%), housewives (21,05%) and market workers (22,81 %). Conclusions: our data reaffirm previous researches that relate the prevalence ofbacterial vaginosis caused by G vaginalis and /or Mobiluncus sp. to low instruction degree in sexually active women.

Micrococcal botryomycosis of the left temporal region.

Botryomycosis arises from chronic infections produced by low-virulence organisms in an altered host environment. Staphylococci have been the most common organisms implicated, but various other bacteria have also been identified in human botryomycosis lesions. The relative balance between the host's resistance and the microorganism's virulence may be altered in some way that perpetuates the growth of the lesions in a symbiotic fashion. The diagnosis of botryomycosis is one that is often easily overlooked because it can be confused with other mycetomas such as actinomycosis and nocardosis. We report here a case of micrococcal botryomycosis that occurred in the left temporal region in a 70 year-old male, which was diagnosed by the help of a histopathological examination and microbial cultures.

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.

Rhodococcus equi--an emerging human pathogen in immunocompromized hosts: a report of four cases from Malaysia.

Rhodococcus equi, a recognized pathogen in horses, is emerging as a human opportunistic pathogen, especially in immunocompromized hosts. We describe four immunocompromized patients who had serious R. equi infections with an overall mortality of 75%. The natural habitat of R. equi is soil, particularly soil contaminated with animal manure. Necrotizing pneumonia is the commonest form of infection but extrapulmonary infections, such as wound infections and subcutaneous abscess, have also been described in humans. R. equi is cultured easily in ordinary non-selective media. Large, smooth, irregular colonies appear within 48 hours. It is a facultative, intracellular, nonmotile, non-spore forming, gram-positive coccobacillus, which is weakly acid-fast staining and bears a similarity to diphtheroids. It forms a salmon-colored pigment usually after 48 hours incubation. A particular characteristic of this organism is that it undergoes synergistic hemolysis with some bacteria on sheep blood agar. R. equi may be misidentified as diphtheroids, Mycobacterium species, or Nocardia. In vitro R. equi is usually susceptible to erythromycin, ciprofloxacin, vancomycin, aminoglycosides, rifampin, imipenem and meropenem. The organism can be difficult to eradicate, making treatment challenging. Increased awareness of the infection may help with early diagnosis and timely treatment.

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.