RESUMO
We present the case of a 71-year-old man who developed sepsis caused by Capnocytophaga canimorsus as a result of being bitten by his own dog. Positive blood cultures were obtained, but due to difficulties in determining the bacterial species, the patient was treated empirically with ceftriaxone and levofloxacin. After using the recommended empirical therapy, the patient's condition improved. Capnocytophaga canimorsus is difficult to identify, among others, due to its long growth time and specific development conditions (capnophiles). These Gram-negative bacilli cause a number of diseases in humans, ranging from infections of the skin and subcutaneous tissue, through peritonitis, to sepsis. The portal of infection with these bacteria is most often a wound caused by an animal bite. Additional risk factors that increase the risk of developing a severe infection and even death include older age, concomitant chronic diseases, and immunosuppression.
Assuntos
Antibacterianos , Mordeduras e Picadas , Capnocytophaga , Infecções por Bactérias Gram-Negativas , Humanos , Cães , Mordeduras e Picadas/microbiologia , Mordeduras e Picadas/complicações , Animais , Masculino , Idoso , Infecções por Bactérias Gram-Negativas/tratamento farmacológico , Infecções por Bactérias Gram-Negativas/microbiologia , Infecções por Bactérias Gram-Negativas/diagnóstico , Capnocytophaga/isolamento & purificação , Antibacterianos/uso terapêutico , Sepse/microbiologia , Sepse/etiologia , Sepse/tratamento farmacológico , Levofloxacino/uso terapêutico , Ceftriaxona/uso terapêuticoRESUMO
We report a case of Vandammella animalimorsus in an adult female patient following a cat scratch/bite. Animal bite/scratches may lead to zoonotic transmission of bacteria that subsequently lead to infection. Wound management and antimicrobial therapy is often necessary. The organism was initially misidentified as Neisseria animaloris/zoodegmatis and highlights the difficulty of correctly identifying some bacteria in clinical microbiology laboratories.
Dogs and cats carry bacteria that are not carried in humans. Dog and cat bites or scratches may lead to these bacteria being spread to humans. This can lead to infection. These infections are usually treated by wound care and antibiotics. We describe a case of infection in a human with a bacteria from a cat following a cat bite/scratch to the patient's leg and discuss how the infection was diagnosed and treated.
Assuntos
Mordeduras e Picadas , Feminino , Animais , Gatos , Humanos , Mordeduras e Picadas/microbiologia , Mordeduras e Picadas/complicações , Antibacterianos/uso terapêutico , Perna (Membro)/patologia , Perna (Membro)/microbiologia , Infecções por Enterobacteriaceae/microbiologia , Infecções por Enterobacteriaceae/diagnóstico , Infecções por Enterobacteriaceae/tratamento farmacológico , Enterobacteriaceae/isolamento & purificação , AdultoRESUMO
INTRODUCTION: Patients and physicians often underestimate cat bite injuries. The deep and narrow wound seals quickly and provides an environment for the inoculated saliva and bacteria. Interestingly, the literature reports no bacterial growth in the microbiological workup of wound swaps in up to 43%. The time between bite injury and the first clinical presentation, the start of antibiotic treatment and surgical debridement might affect these findings. Therefore, the current project examines if (1) these factors impact the outcome of microbiological results following cat bite injuries and (2) the detection of bacterial growth leads to higher complication rates, longer hospital stays, longer total treatment time, or higher total treatment costs. MATERIALS AND METHODS: This single-center retrospective study analyzed data from 102 adult patients. All patients received antibiotic and surgical treatment following a cat bite injury. Microbiological samples were collected during surgery in all cases. The time from the bite incident to the first presentation, beginning of antibiotic administration, and surgical debridement was calculated. Demographic data, complication rate, length of hospital stay, total treatment time, and total treatment costs were recorded. (1) A generalized linear model was fitted using the microbiological outcome as the dependent variable. (2) Two groups (negative or positive microbiological results) were formed and statistically compared. RESULTS: The median age was 50 (SD 16), and 72% were female. (1) The time from the bite incident to the first clinical presentation, antibiotic administration, or surgical treatment was not associated with the outcome of the microbiological result. (2) No significant differences were observed between the two groups. CONCLUSIONS: Our data do not suggest that early antibiotic administration or delayed surgical treatment affects the outcome of the microbiological workup following cat bite injuries to the hand and forearm. The microbiological outcome did not affect the complication rate, treatment time, and total treatment costs.
Assuntos
Antibacterianos , Mordeduras e Picadas , Traumatismos da Mão , Mordeduras e Picadas/complicações , Mordeduras e Picadas/microbiologia , Mordeduras e Picadas/cirurgia , Feminino , Animais , Humanos , Masculino , Gatos , Estudos Retrospectivos , Pessoa de Meia-Idade , Antibacterianos/uso terapêutico , Adulto , Traumatismos da Mão/cirurgia , Traumatismos da Mão/microbiologia , Desbridamento , Traumatismos do Antebraço/cirurgia , Resultado do Tratamento , Idoso , Tempo de Internação/estatística & dados numéricosRESUMO
Pasteurellosis is a common zoonotic infection that occurs after an animal bite or scratch (B/S). We compared the clinical features of six patients with non-B/S pasteurellosis with those of 14 patients with B/S infections. Pasteurella multocida was identified with matrix-assisted laser desorption/ionization time-of-flight mass spectrometry in all six non-B/S infections, whereas 13 of the 14 B/S infections were identified with diagnostic kits. The non-B/S infections were pneumonia (n = 3), skin and soft tissue infections (n = 2), and bacteremia (n = 1). Pneumonia occurred in two patients with underlying pulmonary disease, whereas ventilator-associated pneumonia developed in one patient with cerebral infarction. Pasteurella multocida was isolated from a blood specimen and nasal swab from a patient with liver cirrhosis (Child-Pugh class C) and diabetes. Cellulitis developed in one patient with diabetes and normal-pressure hydrocephalus, who had an open wound following a fall, and in one patient with diabetes and a foot ulcer. Three patients with non-B/S infections had no pet and no episode of recent animal contact. The rate of moderate-to-severe comorbidities was significantly higher in patients with non-B/S infections than in those with B/S infections (100% and 14.3%, respectively, p < 0.001). In conclusion, non-B/S infections can develop in patients with chronic pulmonary disease, invasive mechanical ventilation, or open wounds, or who are immunocompromised, irrespective of obvious animal exposure. In contrast to B/S infections, non-B/S pasteurellosis should be considered opportunistic.
Assuntos
Mordeduras e Picadas , Infecções por Pasteurella , Pasteurella multocida , Humanos , Infecções por Pasteurella/microbiologia , Infecções por Pasteurella/diagnóstico , Animais , Masculino , Feminino , Pasteurella multocida/isolamento & purificação , Pessoa de Meia-Idade , Idoso , Mordeduras e Picadas/complicações , Mordeduras e Picadas/microbiologia , Idoso de 80 Anos ou mais , Adulto , Bacteriemia/microbiologia , Bacteriemia/diagnósticoAssuntos
Actinomyces , Mordeduras e Picadas , Animais , Humanos , Masculino , Cavalos , Mordeduras e Picadas/microbiologiaRESUMO
BACKGROUND: Capnocytophaga, a bacteria native to the oral flora of canines, in rare cases can lead to severe infections resulting in septic shock, respiratory tract infection, and multiple organ failure. In case of trauma following animal bites with rapidly progressing clinical courses, also adjunctive therapeutic measures such as extracorporeal blood purification therapies might be beneficial. CASE PRESENTATION: We report on a 68-year-old male who was hospitalized with fever, oliguria and repeated vomiting after suffering a minor bite by his dog. On admission, he was diagnosed with sepsis. In addition, his coagulation status was markedly deranged resulting in the administration of mass transfusions to stabilize his coagulative status. Following detection of Capnocytophaga canimorsus, anti-infective therapy was initiated. In the context of a progressive respiratory deterioration and an increasing vigilance disorder, he had to be intubated. Due to development of renal failure, dialysis was started in conjunction with CytoSorb hemoadsorption therapy to control the hyperinflammatory condition. All of the applied therapeutic measures led to a rapid clinical stabilization, a control of the hyperinflammatory situation, and an improvement in his neurological status. The therapy was well tolerated with no complications encountered. CONCLUSIONS: This case supports the clinical recognition of severe Capnocytophaga infection that can lead to critical conditions even in immunocompetent patients. Combined broad spectrum antibiotic therapy, mass transfusions, CRRT, and CytoSorb hemoadsorption therapy resulted in a control of the critical situation. However, further research is needed to fully elucidate the role of hemoadsorption in this rare but life-threatening setting.
Assuntos
Mordeduras e Picadas , Hemadsorção , Sepse , Trombocitopenia , Idoso , Animais , Masculino , Capnocytophaga , Insuficiência de Múltiplos Órgãos/microbiologia , Insuficiência de Múltiplos Órgãos/terapia , Sepse/microbiologia , Sepse/terapia , Mordeduras e Picadas/complicações , Mordeduras e Picadas/microbiologia , HumanosRESUMO
CDC group non-oxidizer (NO)-1 is the provisional name designated in 1993 for phenotypically similar, Gram-stain-negative bacilli recovered primarily from human wound infections after animal bites. Otherwise, this group has been rarely alluded to in recent literature. CDC NO-1 strains had been described as non-motile, asaccharolytic, oxidase-negative, catalase-positive, nitrate-reducing bacilli, with predominate cellular fatty acids of C10â:â0 3OH, C16â:â1 ω7c, C16â:â0 and C18â:â1 ω7c. Only one 16S rRNA gene sequence deposited in NCBI (accession no. DQ054782) had been identified as CDC group NO-1 prior to this study. That sequence was closely related (>99â% identity) to sequences called 'Xenophilus species' from canine (JN713339) and feline (KM461961) oral microbiomes as well as to sequences derived from human strains (this study). Some of the 11 isolates delineated here were recovered from human wound infections subsequent to cat/dog bites; others were from wounds (links to animal bites not described) and two were recovered from dialysates. After 16S rRNA and whole genome sequencing, the isolates were found to be most closely related to each other but fell into two distinct genera assignable to the family Comamonadaceae, provisionally discussed here as CDC group NO-1 and CDC group NO-1-like. The genomes of CDC group NO-1 isolates ranged from 3.08 to 3.38 MB with G+C contents of 65.08-66.92â%; genomes derived from CDC group NO-1-like strains were smaller, ranging from 2.72 to 2.82 Mb with G+C contents of 62.87-63.0âmol%. Based on a polyphasic study of these bacteria, we describe Vandammella animalimorsus gen. nov., sp. nov. and Franklinella schreckenbergeri gen. nov., sp. nov. for these clusters.
Assuntos
Mordeduras e Picadas , Comamonadaceae , Filogenia , Animais , Técnicas de Tipagem Bacteriana , Composição de Bases , Mordeduras e Picadas/microbiologia , Gatos , Centers for Disease Control and Prevention, U.S. , Comamonadaceae/classificação , DNA Bacteriano/genética , Cães , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Estados UnidosAssuntos
Abscesso/microbiologia , Bacteriemia , Febre por Mordedura de Rato , Streptobacillus , Animais , Bacteriemia/diagnóstico , Bacteriemia/tratamento farmacológico , Mordeduras e Picadas/microbiologia , Humanos , Perna (Membro)/patologia , Extremidade Inferior , Masculino , Pessoa de Meia-Idade , Febre por Mordedura de Rato/diagnóstico , Febre por Mordedura de Rato/tratamento farmacológico , RatosRESUMO
Tail biting is an abnormal behaviour that causes stress, injury and pain. Given the critical role of the gut-microbiota in the development of behavioural problems in humans and animals, the aim of this study was to determine whether pigs that are biters, victims of tail biting or controls (nine matched sets of pigs) have a different microbiota composition, diversity and microbial metabolite profile. We collected faecal and blood samples from each individual for analysis. The gut microbiota composition was most different between the biter and the control pigs, with a higher relative abundance of Firmicutes in tail biter pigs than the controls. Furthermore, we detected differences in faecal and plasma short chain fatty acids (SCFA) profiles between the biter and victim pigs, suggesting physiological differences even though they are kept in the same pen. Thus, in addition to supporting an association between the gut microbiota and tail biting in pigs, this study also provides the first evidence of an association between tail biting and SCFA. Therefore, further research is needed to confirm these associations, to determine causality and to study how the SCFA profiles of an individual play a role in the development of tail biting behaviour.
Assuntos
Comportamento Animal , Mordeduras e Picadas/veterinária , Microbioma Gastrointestinal , Suínos/microbiologia , Animais , Mordeduras e Picadas/sangue , Mordeduras e Picadas/microbiologia , Estudos de Casos e Controles , Ácidos Graxos Voláteis/sangue , Fezes/química , Feminino , Masculino , Suínos/sangue , CaudaRESUMO
INTRODUCCIÓN: Las mordeduras causadas por animales de compañía constituyen el 5% de las heridas traumáticas registradas en los servicios de urgencias. OBJETIVO: Conocer los principales agentes infecciosos presentes en las mordeduras provocadas por perros y gatos, tanto de forma individual como conjunta; así como los factores que favorecen la infección. METODOLOGÍA: Se realizó una búsqueda bibliográfica en Pub-Med con la siguiente estrategia de búsqueda: (("Bites, Human"[Mesh]) OR "Bites and Stings"[Mesh]) AND "Infection"[Mesh]. Se incluyeron 24 trabajos en la síntesis cualitativa escritos en lengua inglesa o española, casos clínicos o descriptivos y publicados entre los años 2000 y 2019. RESULTADOS: Las especies más frecuentemente aisladas fueron Capnocytophaga canimorsus en perros y Pasteurella multocida en gatos. La existencia de comorbilidades en el individuo, la mordedura en la mano, o la presencia de signos de alteración del estado general del individuo mordido fueron considerados como factores de riesgo para el desarrollo de la infección tras la mordedura. CONCLUSIONES: Todos los afectados por mordeduras animales deben recibir asistencia médica y considerar la administración de una pauta de profilaxis antimicrobiana con el fin de reducir el riesgo de shock séptico. Por otro lado, es importante advertir al laboratorio de microbiología de la naturaleza de las muestras clínicas obtenidas para alcanzar el mejor diagnóstico etiológico.
BACKGROUND: Bites caused by pets constitute 5% of the traumatic injuries registered in the emergency services. AIM: To know the main infectious agents present in dog and cat bites, both individually and jointly, in humans, as well as the predisposing factors that favor infection and its spread. METHODS: A bibliographic search was carried out in PubMed with the following search strategy: (("Bites, Human" [Mesh]) OR "Bites and Stings" [Mesh]) AND "Infection" [Mesh]. Twenty-four papers were included in the qualitative synthesis written in English or Spanish, clinical or descriptive cases and published between 2000 and 2019. Results: Most frequently isolated species were Capnocytophaga canimorsus in dogs and Pasteurella multocida in cats. The existence of comorbidities in the individual, the bite on the hand, or the presence of signs of alteration of the general state of the bitten individual were considered as risk factors for the development of infection after the bite. CONCLUSIONS: All patients with animal bites should receive medical assistance, and the administration of an antibiotic prophylaxis regimen should be considered to reduce the risk of septic shock. Besides, it is important to advise the microbiology laboratory of the nature of the clinical samples obtained in order to reach the best etiological diagnosis.
Assuntos
Humanos , Animais , Gatos , Cães , Mordeduras e Picadas/microbiologia , Doenças do Gato , Doenças do Cão , Capnocytophaga/isolamento & purificação , Pasteurella multocida/isolamento & purificaçãoAssuntos
Artrite Infecciosa/etiologia , Mordeduras e Picadas/complicações , Gatos , Piomiosite/etiologia , Animais , Artrite Infecciosa/diagnóstico por imagem , Artrite Infecciosa/patologia , Mordeduras e Picadas/microbiologia , Humanos , Articulação do Joelho , Masculino , Piomiosite/diagnóstico , Coxa da Perna , Adulto JovemRESUMO
BACKGROUND: Capnocytophaga canimorsus is a Gram-negative capnophilic rod and part of dogs/cats' normal oral flora. It can be transmitted by bites, scratches, or even by contact of saliva with injured skin. Asplenic patients and patients with alcohol abuse are at particular risk for fulminant C. canimorsus sepsis. However, also immunocompetent patients can have a severe or even fatal infection. This is the first case of a severe C. canimorsus infection in an immunocompromised host complicated by acute renal cortical necrosis with a "reverse rim sign" in contrast-enhanced computed tomography on hospital admission. CASE PRESENTATION: We report the case of a 44-year functionally asplenic patient after an allogeneic stem cell transplantation, who presented with septic shock after a minor dog bite injury 4 days prior. Because of abdominal complaints, epigastric pain with local peritonism, and radiological gallbladder wall thickening, an abdominal focus was suspected after the initial work-up. The patient underwent emergent open cholecystectomy, but the clinical suspicion of abdominal infection was not confirmed. Septic shock was further complicated by cardiomyopathy and disseminated intravascular coagulation. As a causative pathogen, C. canimorsus could be isolated. The clinical course was complicated by permanent hemodialysis and extensive acral necrosis requiring amputation of several fingers and both thighs. CONCLUSION: We present a severe case of a C. canimorsus infection in a functionally asplenic patient after a minor dog bite. The clinical course was complicated by septic shock, disseminated intravascular coagulation, and the need for multiple amputations. In addition, the rare form of acute renal failure - bilateral acute renal cortical necrosis - was visible as "reverse rim sign" on computed tomography scan. This case is an example of the potential disastrous consequences when omitting pre-emptive antibiotic therapy in wounds inflicted by cats and dogs, particularly in asplenic patients.
Assuntos
Mordeduras e Picadas/complicações , Mordeduras e Picadas/microbiologia , Capnocytophaga , Infecções por Bactérias Gram-Negativas/complicações , Necrose do Córtex Renal/microbiologia , Adulto , Amputação Cirúrgica , Animais , Antibacterianos/uso terapêutico , Mordeduras e Picadas/terapia , Capnocytophaga/isolamento & purificação , Capnocytophaga/patogenicidade , Coagulação Intravascular Disseminada/microbiologia , Coagulação Intravascular Disseminada/patologia , Coagulação Intravascular Disseminada/terapia , Cães , Feminino , Infecções por Bactérias Gram-Negativas/patologia , Infecções por Bactérias Gram-Negativas/terapia , Humanos , Hospedeiro Imunocomprometido , Infecções Intra-Abdominais/etiologia , Infecções Intra-Abdominais/microbiologia , Infecções Intra-Abdominais/terapia , Necrose do Córtex Renal/etiologia , Necrose do Córtex Renal/terapia , Choque Séptico/microbiologia , Choque Séptico/terapia , SuíçaRESUMO
ABSTRACT: Capnocytophaga canimorsus is a bacteria commonly found in the normal oral cavity of dogs that can cause bacteremia in immunocompromised patients following a dog bite. This case describes sepsis and disseminated intravascular coagulation associated with C. canimorsus in a patient with a history of alcohol abuse. Clinicians must be alert to the risk factors for this infection and provide appropriate prophylaxis following dog bites.
Assuntos
Antibacterianos/administração & dosagem , Bacteriemia/microbiologia , Bacteriemia/terapia , Mordeduras e Picadas/microbiologia , Mordeduras e Picadas/terapia , Capnocytophaga/patogenicidade , Coagulação Intravascular Disseminada/microbiologia , Coagulação Intravascular Disseminada/terapia , Cães/microbiologia , Infecções por Bactérias Gram-Negativas , Hospedeiro Imunocomprometido , Meningite/microbiologia , Meningite/terapia , Sepse/microbiologia , Sepse/terapia , Alcoolismo , Amputação Cirúrgica , Animais , Gangrena/microbiologia , Gangrena/cirurgia , Humanos , Masculino , Pessoa de Meia-IdadeAssuntos
Antibacterianos/uso terapêutico , Mordeduras e Picadas/microbiologia , Animais , Mordeduras e Picadas/complicações , Cães , Serviço Hospitalar de Emergência , Humanos , Guias de Prática Clínica como Assunto , Ensaios Clínicos Controlados Aleatórios como Assunto , Infecção dos Ferimentos/tratamento farmacológico , Infecção dos Ferimentos/microbiologia , Infecção dos Ferimentos/prevenção & controleAssuntos
Antibacterianos/uso terapêutico , Mordeduras e Picadas/tratamento farmacológico , Prescrição Inadequada/prevenção & controle , Infecção dos Ferimentos/tratamento farmacológico , Animais , Mordeduras e Picadas/microbiologia , Cães , Serviço Hospitalar de Emergência , Humanos , Guias de Prática Clínica como Assunto , Infecção dos Ferimentos/microbiologia , Infecção dos Ferimentos/prevenção & controleRESUMO
Pasteur discovered the causative agent of fowl cholera (Pasteurella multocida) in 1880. Since then, multiple zoonotic infections affecting humans have been reported. P. multocida infections usually result from bites of cats or dogs. The earliest reports of nonbite transmissions (NBTs) were attributed to cat scratches and lung colonization. More recently, multiple modes of unusual NBTs have been reported, including animal exposures with no direct contact. Here, we report 79 cases of pet-associated infections, with 34 NBTs. Previously unreported and unsuspected, novel modes of NBTs presented include stepping on dog drool infecting a submetatarsal ulcer, contamination of a wound by socks covered with cat hair and dander resulting in P. multocida bacteremia, stumbling over a dog and falling while drunk and abrasions contaminated with dog saliva resulting in wound infection, and severe epiglottitis and supraglottitis after eating peanut butter and crackers half eaten by a dog. Cat bites were more common than dog bites. Both bite and nonbite infections were more common in the elderly, with more older patients in the nonbite group. Upper extremity bites were more than lower extremity bites for both cats and dogs. NBTs were associated with more co-morbidities and resulted in more life-threatening infections than bites, confirming the findings of a prior smaller series. Open wounds were the most common point of entry for nonbite infections, with majority in the lower extremity. Based on this study and prior reports, pet owners must protect open wounds and individuals with certain underlying conditions and infants should avoid pet exposure completely. Our findings and animal transmission of bite and nonbite P. multocida infections reported in literature are summarized.
Assuntos
Mordeduras e Picadas/epidemiologia , Infecções por Pasteurella/epidemiologia , Infecções por Pasteurella/transmissão , Pasteurella multocida/isolamento & purificação , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Animais , Mordeduras e Picadas/microbiologia , Gatos , Criança , Pré-Escolar , Cães , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Animais de Estimação , Estudos Retrospectivos , Infecção dos Ferimentos/microbiologia , Infecção dos Ferimentos/transmissão , Zoonoses/microbiologia , Zoonoses/transmissãoRESUMO
Beneficial effects of cold atmospheric argon plasma (CAAP) on wound healing and its capacity for bacterial decontamination has recently been documented. First, in vivo studies in small animals did not prove any decontamination effect in canine bite wounds. The present study evaluated the overall decontamination effect of CAAP for different bacteria frequently encountered in canine bite wounds with respect to growth phase, initial bacteria concentration and treatment duration. Standard strains of Escherichia (E.) coli, Staphylococcus (S.) pseudintermedius, S. aureus, Streptococcus (S.) canis, Pseudomonas (P.) aeruginosa and Pasteurella multocida were investigated. To evaluate the influence of the bacterial growth phase, each bacterium was incubated for three and eight hours, before CAAP treatment. Three different bacterial concentrations were created per bacterium and growth phase, and were exposed to CAAP for 30â¯s, 1â¯min and 2â¯min. CAAP treatment resulted in acceptable decontamination rates (range 98.9-99.9%) in all bacteria species in vitro; however, differences in susceptibility were detected. Decontamination rate was mainly influenced by initial bacterial concentration and treatment time. Growth phase only influenced decontamination in S. pseudintermedius. Treatment time significantly (Pâ¯<â¯.05) correlated with the decontamination rate in E. coli, S. canis and S. aureus, with an exposure time of 2â¯min being most effective. Initial bacterial concentration significantly (Pâ¯<â¯.05) influenced decontamination in Pasteurella multocida and P. aeruginosa, in which treatment time was not as important. CAAP exerts effective antibacterial activity against the tested bacteria strains in vitro, with species specific effects of treatment time, growth phase and concentration.
Assuntos
Argônio/farmacologia , Bactérias/efeitos dos fármacos , Mordeduras e Picadas/microbiologia , Desinfecção/métodos , Gases em Plasma/farmacologia , Animais , Descontaminação/métodos , Desinfetantes/farmacologia , Cães , Testes de Sensibilidade Microbiana , Cicatrização/efeitos dos fármacosRESUMO
A blood smear examination led to the diagnosis of severe bacterial infection in a splenectomized patient. The knowledge of a relevant clinical information (recent dog bite) could have led to immediate presumptive identification of the causative agent, Capnocytophaga canimorsus.