Shock séptico de foco respiratorio por Pasteurella multocida en un paciente inmunocompetente. Caso Clínico / Septic shock originating from a pulmonary focus caused by Pasteurella multocida. Report of one case

Pasteurella multocida is a gram-negative coccobacillus bacterium found as a commensal in the oropharynx of domestic animals such as cats and dogs and some farm animals. Soft tissue infections and occasionally bacteremia in immunocompromised patients with direct contact with animals are described. We report a 61 year old male with a history of scratches and close contact with domestic cats, with a septic shock originating from a pulmonary focus, requiring mechanical ventilation and vasopressors. Blood cultures disclosed the presence of Pasteurella multocida. He responded successfully to antimicrobials.

Bacteriemia por Pasteurella multocida asociada al contacto con un animal doméstico / Pasteurella multocida bacteremia associated with contact with a domestic animal: case report

Resumen Pasteurella multocida es reconocida por ser una de las especies más frecuentemente aisladas en la microbiota oral de animales domésticos y salvajes; asociadas a infecciones de piel y tejidos blandos secundarias a mordeduras y rasguños. Las infecciones sistémicas son poco frecuentes, asociadas a la diseminación desde infecciones localizadas y a factores de riesgo asociados a inmunosupresión. Presentamos un caso de bacteriemia por Pasteurella multocida en un paciente de 88 años, relacionada con alimentos compartidos con su mascota; un mecanismo de producción de bacteriemia nunca antes descrito en la literatura médica.

Pasteurella species are known to be one of the most frequently isolated in oral microbiota of domestic and wild animals, because of that, they are associated with skin and soft tissues infections secondary to bites and scratches. Systemic infections are uncommon, but are associated with dissemination from localized infections and some risks factors related to immunosuppression. We report a case of Pasteurella multocida bacteremia in an 88 years old patient, associated with food sharing with his dog; a bacteremia mechanism never described before in the medical literature.

Virulence genes and antimicrobial resistance of Pasteurella multocida isolated from poultry and swine

Abstract Pasteurella multocida causes atrophic rhinitis in swine and fowl cholera in birds, and is a secondary agent in respiratory syndromes. Pathogenesis and virulence factors involved are still poorly understood. The aim of this study was to detect 22 virulence-associated genes by PCR, including capsular serogroups A, B and D genes and to evaluate the antimicrobial susceptibility of P. multocida strains from poultry and swine. ompH, oma87, plpB, psl, exbD-tonB, fur, hgbA, nanB, sodA, sodC, ptfA were detected in more than 90% of the strains of both hosts. 91% and 92% of avian and swine strains, respectively, were classified in serogroup A. toxA and hsf-1 showed a significant association to serogroup D; pmHAS and pfhA to serogroup A. Gentamicin and amoxicillin were the most effective drugs with susceptibility higher than 97%; however, 76.79% of poultry strains and 85% of swine strains were resistant to sulphonamides. Furthermore, 19.64% and 36.58% of avian and swine strains, respectively, were multi-resistant. Virulence genes studied were not specific to a host and may be the result of horizontal transmission throughout evolution. High multidrug resistance demonstrates the need for responsible use of antimicrobials in animals intended for human consumption, in addition to antimicrobial susceptibility testing to P. multocida.

Antimicrobial resistance and virulence gene profiles in P. multocida strains isolated from cats

Cats are often described as carriers of Pasteurella multocida in their oral microbiota. This agent is thought to cause pneumonia, conjunctivitis, rhinitis, gingivostomatitis, abscess and osteonecrosis in cats. Human infection with P. multocida has been described in several cases affecting cat owners or after cat bites. In Brazil, the cat population is approximately 21 million animals and is increasing, but there are no studies of the presence of P. multocida in the feline population or of human cases of infection associated with cats. In this study, one hundred and ninety-one healthy cats from owners and shelters in São Paulo State, Brazil, were evaluated for the presence of P. multocida in their oral cavities. Twenty animals were positive for P. multocida, and forty-one strains were selected and characterized by means of biochemical tests and PCR. The P. multocida strains were tested for capsular type, virulence genes and resistance profile. A total of 75.6% (31/41) of isolates belonged to capsular type A, and 24.4% (10/41) of the isolates were untypeable. None of the strains harboured toxA, tbpA or pfhA genes. The frequencies of the other genes tested were variable, and the data generated were used to build a dendrogram showing the relatedness of strains, which were clustered according to origin. The most common resistance profile observed was against sulfizoxazole and trimethoprim-sulphamethoxazole.

Effect of particulate matter less than 10µm (PM10) on mortality in Bogota, Colombia: a time-series analysis, 1998-2006 / Efecto del material particulado menor a 10µm (PM10) sobre la mortalidad en Bogotá, Colombia: un análisis de series de tiempo 1998-2006

Objective. To analyze the association between daily mortality from different causes and acute exposure to particulate matter less than 10 microns in aerodynamic diameter (PM10), in Bogota, Colombia. Materials and methods. A time-series ecological study was conducted from 1998 to 2006. The association between mortality (due to different causes) and exposure was analyzed using single and distributed lag models and adjusting for potential confounders. Results. For all ages, the cumulative effect of acute mortality from all causes and respiratory causes increased 0.71% (95%CI 0.46-0.96) and 1.43% (95%CI 0.85-2.00), respectively, per 10µg/m³ increment in daily average PM10 with a lag of three days before death. Cumulative effect of mortality from cardiovascular causes was -0.03% (95%CI -0.49-0.44%) with the same lag. Conclusions. The results suggest an association between an increase in PM10 concentrations and acute mortality from all causes and respiratory causes.

Objetivo. Analizar la asociación entre la mortalidad diaria debida a distintas causas y la exposición aguda a partículas menores de 10 micras de diámetro aerodinámico (PM10), en Bogotá, Colombia. Material y métodos. Se realizó un estudio ecológico de series de tiempo (1998-2006). La asociación entre mortalidad y exposición se analizó ajustando modelos de retraso simple y retraso distribuido para diferentes causas de mortalidad. Resultados. En todas las edades, el riesgo acumulado en la mortalidad aguda por todas las causas y causa respiratoria aumentó 0.71% (IC95% 0.46-0.96) y 1.43% (IC95% 0.85-2.00), respectivamente, por incremento de 10µg/m³ en el promedio diario de PM10, tomando un retraso de tres días anteriores al deceso, mientras el riesgo acumulado en la mortalidad por causa cardiovascular fue de -0.03% (IC95% -0.49-0.44), para el mismo retraso. Conclusiones. Los resultados sugieren asociación entre el incremento de las concentraciones de PM10 y la mortalidad aguda por todas las causas y causa respiratoria.

Evaluación de dos técnicas de subtipificación molecular para el estudio de Pasteurella multocida / Evaluation of two techniques of molecular subtyping to study Pasteurella multocida

Se determinó la tipibilidad, la reproducibilidad y el poder discriminatorio de ERIC-PCR y ApaI-PFGE para establecer la relación genética de cepas de Pasteurella multocida. Se estudiaron 49 cepas de diferente origen, subespecie, biotipo, grupo capsular, serotipo somático y perfil de resistencia antimicrobiana. Por ERIC-PCR se establecieron 31 patrones, los que presentaron entre 10 y 14 bandas en un rango comprendido entre 0,2 y 1,2 kb. Por ApaI-PFGE se detectaron 37 patrones de restricción, los cuales presentaron entre 7 y 15 bandas bien definidas de 34 a 450 kb. La tipibilidad de ERIC-PCR fue del 100% (T=1) y la de ApaI-PFGE del 94% (T=0,94). La reproducibilidad de ambas técnicas fue del 100% (R=1); sin embargo, el poder discriminatorio de ERIC-PCR fue 93% (D=0,93) y el de ApaI-PFGE 98% (D=0,98). Mediante ambas técnicas fue posible agrupar las cepas con relación epidemiológica y diferenciar claramente las cepas no relacionadas. Se demostró el valor de ERIC-PCR y ApaI-PFGE para complementar estudios epidemiológicos, principalmente si las cepas en estudio son analizadas por ambas técnicas.

Typeability, reproducibility, and discriminatory power of ERIC-PCR and ApaI-PFGE to establish the genetic relation of P. multocida strains were determined. Forty-nine strains of different source, biotype, capsular group, somatic serotype, and resistance to antimicrobials were studied. By ERIC-PCR, 31 patterns were defined with 10 to 14 bands in a rank of 0.2 and 1.2 kb. By ApaI-PFGE, 37 restriction patterns were established with 7 to 15 bands of 34 to 450 kb. Typeability was 100% (T=1) for ERIC-PCR, and 94% (T=0.94) for ApaI-PFGE. Reproducibility of both techniques was 100% (R=1). Discriminatory power was 93% (D=0.93) for ERIC-PCR, and 98% (D=0.98) for ApaI-PFGE. By using both techniques, epidemiologically related strains were grouped, and unrelated strains were clearly differentiated. The value of ERIC-PCR and ApaI-PFGE as complements to epidemiologic studies was demonstrated, especially when both techniques were used to analyze the strains.

Detection of Pasteurella multocida in experimentally infected embryonated chicken eggs by PCR assay.

Applicability of polymerase chain reaction (PCR) assay to detect Pasteurella multocida in experimentally infected embryonated chicken egg was assessed in the present study. PCR assay rapidly and specifically detected the genome of P. multocida in amniotic fluid, allantoic fluid and homogenates of infected embryo and its membranes. The sensitivity of detection was as low as 20 bacterial cells/ml of allantoic or amniotic fluids. Detection of P. multocida in dead embryos by PCR was possible up to 6 and 30 days or more following storage of dead embryos at 37 degrees C, and at 4 degrees C as well as at -20 degrees C, respectively. The study revealed that PCR assays could be employed directly for detection and confirmation of P. multocida infection in experimentally infected chicken embryos.

Characteristics of Pasteurella multocida isolated from humans, swine and poultry in Thailand.

Pasteurella multocida is a pathogen of animals and humans. Most of the patients have been associated with animals but many cases had not contacted them. The failure to diagnose P. multocida infections is mostly due to misidentification on gram stained smears and inadequate laboratory identification techniques. In order to compile detailed characteristics of the organism we studied the physical and biochemical properties of 70 isolates of P. multocida - 17 human, 23 swine and 30 poultry. All isolates produced catalase, oxydase, indol, nitrate reduction and ornithine decarboxylase. They failed to produce urease, gelatinase, methyl red, acetoin and could not grow on MacConkey agar, SS-agar, in nutrient broth with 0% or 6% NaCl. With respect to fermentable sugars, all isolates consistantly produced acid from glucose, mannitol and mannose. None of the cultures fermented lactose, maltose and dulcitol. Marked variations in the patterns of fermentation of arabinose and xylose were found. The characteristics tested are important to facilitate identification of P. multocida but could not be used to differentiate the host of the bacterium.

Serotipos de Pasteurella haemolytica en pulmones neumóticos de ovinos en México / Serotypes of Pasteurella haemolytica isolated from pneumonic sheeps in Mexico

Se investigó la distribución de los serotipos de Pasteurella haemolytica en pulmones neumónicos de ovinos en México. De un total de 860 pulmones neumónicos revisados, provenientes de 2 poblaciones de ovinos, se aislaron 120 cepas de P. haemolytica (14%). Las cepas aisladas fueron serotipificadas con los 12 antisueros monoespecíficos contra P. haemolytica, mediante la prueba de aglutinación rápida en placa. Los serotipos más comunes fueron el Al, A2, A5 y A9, representando el 22%, 16%, 11% y 7%, respectivamente. El 27% de los aislamientos (33 cepas) correspondió a cepas no tipificables. Al comparar las 2 poblaciones de ovinos muestreadas, se apreció que existieron diferencias en la frecuencia con que se aislaron los diferentes serotipos de P. haemolytica. Estos resultados deberán ser considerados en la elaboración de bactérias para prevenir la pasteurelosis pulmonar en ovinos; ya que éstas deben de contener los serotipos predominantes de la zona geográfica donde se pretende inmunizar a los ovinos