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From Haemobartonella to hemoplasma: molecular methods provide new insights   总被引:1,自引:0,他引:1  
Hemotropic mycoplasmas (aka hemoplasmas) are the causative agents of infectious anemia in numerous mammalian species. Originally known as Haemobartonella and Eperythrozoon species, these organisms have been reclassified within the genus Mycoplasma. The development of new molecular assays has expanded our knowledge of this heterogeneous group of agents and allowed us to study their epidemiology and pathogenesis. The present review summarizes recently gained insights into feline hemotropic mycoplasmas, formerly known as Haemobartonella felis. Besides the two initially identified feline hemoplasma species, Mycoplasma haemofelis and Candidatus Mycoplasma haemominutum, we discovered a third novel hemoplasma in a Swiss pet cat; preliminary results suggest that the pathogenic potential of the latter agent depends on cofactors. In applying PCR-based assays, feline hemoplasma infections have been documented in domestic cats and wild felids worldwide. Differences between the three hemoplasmas in regard to response to antibiotic treatment and establishment of a carrier status have been reported. Additionally, besides an ostensible vector-borne transmission, direct transmission by aggressive interaction of cats or interspecies transmission might play a role in the epidemiology of these organisms. Based on a potential vector-borne and interspecies transmission, a zoonotic potential of hemoplasmas should be further investigated.  相似文献   

3.
Hemobartonellosis is caused by Mycoplasma haemofelis, previously known as Haemobartonella felis. Cats infected with this organism typically develop regenerative anemia. The related species Mycoplasma haemominutum may also cause anemia. The purposes of this study were to use polymerase chain reaction technology to determine if both organisms exist in naturally infected cats from Saskatchewan and Alberta, and to determine if disease manifestation corresponds to mycoplasma species. Thirteen of 18 cats with regenerative anemia were infected, 12 with M. haemofelis and 1 with M. haemominutum. Eight of 22 cats with nonregenerative anemia were infected, 4 with M. haemofelis and 4 with M. haemominutum. Two of 20 cats with normal complete blood (cell) counts were infected with M. haemominutum. Although both mycoplasma species were identified, ill cats were more often infected with M. haemofelis.  相似文献   

4.
Mycoplasmas are frequently isolated from many animal species. In domestic cats, mycoplasmas may be isolated from respiratory and ocular mucosae, but other sites are also occasionally colonized by these organisms. No cases of Mycoplasma species-associated neurologic disease have been reported in cats. We describe a case of Mycoplasma felis-associated meningoencephalitis in a 10-month-old domestic shorthair cat.  相似文献   

5.
The new perspectives about hemotrophic mycoplasma infections in cats and dogs can be summarized as follows: Haemobartonella and Eperythrozoon species infecting the dog and cat have been reclassified as mycoplasmal parasites and given the names M haemofelis (Ohio or large form of H felis), M haemominutum (California or small form of H felis), and M haemocanis (H canis). The prevalence of hemotrophic mycoplasma infections in anemic cats in the United States is about 25% and usually involves M haemofelis. However, nonanemic cats may also be infected most commonly with M haemominutum. Chronic infections with hemotrophic mycoplasmas may promote myeloproliferative disorders in FeLV-infected cats. M haemocanis infection in dogs may be a widespread latent disease in kennel-raised dogs and is being investigated. The PCR assay is exquisitely sensitive for detection of M haemofelis and M haemominutum, and testing of blood donor cats and perhaps dogs should be done regularly. Fleas are involved in the transmission of M haemofelis to the cat, whereas R sanguines may be involved with transmission of M haemocanis to the dog. Treatment with doxycycline effectively controls acute infection in the cat and dog, and enrofloxacin may also be effective in the cat, but none of the antibiotics tested to date consistently clears the parasites.  相似文献   

6.
Hemoplasmas are known causes of anemia in some cats and some Bartonella species have been associated with anemia in people and in dogs. In this retrospective study, we used polymerase chain reaction (PCR) assays to determine the prevalence rates of Mycoplasma haemofelis, 'Candidatus M haemominutum', A phagocytophilum, Ehrlichia species, and Bartonella species DNA in the blood of cats with anemia and a control group of healthy cats. DNA of the organisms was amplified from 22 of 89 cats with anemia (24.7%) and 20 of 87 healthy cats (23.0%). DNA of a hemoplasma was amplified from 18 of 89 cats with anemia (20.2%) and 13 of 87 healthy cats (14.9%); DNA of a Bartonella species was amplified from five of 89 cats with anemia (5.6%) and seven of 87 healthy cats (8.0%). There were no statistically significant differences detected between groups.  相似文献   

7.
Medical records were reviewed for 21 clinically ill cats testing positive for deoxyribonucleic acid (DNA) of "Candidatus Mycoplasma haemominutum" in their blood. Fever, anorexia, lethargy, and anemia were among the most common abnormalities recorded. Thirteen cats were anemic; seven had evidence of other diseases that could have been the primary cause of anemia or activated hemoplasmosis. For six cats, "Candidatus Mycoplasma haemominutum" was the only recognizable cause of the anemia. Of these cats, anemia resolved in one cat without treatment and in three cats that were treated with doxycycline, with or without prednisone. Results of the study suggest that this hemoplasma species can be a primary pathogen in cats.  相似文献   

8.
The mycoplasmas constitute a group of microorganisms placed between bacteria and virus. The name, Mycoplasma, is derived from the mycelial morphology of the organisms. The minimal reproductive unit, the elementary body, measures 0.2-0.5 mum. Unlike bacteria, mycoplasmas are not confined by a rigid cell wall, but just by a thin membrane. For their cultivation, though common bacteriological technique is adequate, especially enriched media are required. Antibiotics, as a rule penicillins, are added to the medium for inhibition of bacteria. Up to the present, 5 porcine species of mycoplasma are known: Mycoplasma suipneumoniae, Mycoplasma hyorhinis, Mycoplasma hyosynoviae, Mycoplasma flocculare, and Acholeplasma granularum. The 4 species first mentioned are very common among swine in Denmark. A. granularum has not been demonstrated so far. Occasionally, other species of mycoplasma are found in swine. M. suipneumoniae is by far the most important porcine mycoplasma, being to-day regarded as the primary etiologic agent in porcine enzootic pneumonia. A pure mycoplasma infection usually results in only weak clinical signs of pneumonia, but the disease may be aggravated by secondary factors as bacteria, parasites, and bad housing conditions. Enzootic pneumonia is usually prevalent only in fattening units, where it tends to persist indefinitely. The mycoplasma infection is practically incurable. Control of the disease is attempted by the SPF-program launched by the Danish Meat Research Institute, Roskilde. In this connexion the high sensitivity of mycoplasmas to physico-chemical influence is of advantage, because it results in a low rate of survival of the organisms outside the host. A further advantage is afforded by the fast that M. suipneumoniae is a definitely swine-specific organism. The rest of the porcine mycoplasmas are of far lesser importance. Yet, M. hyorhinis may produce a sero-fibrinous inflammation of serous cavities and joints in pigs less than 10 weeks old, and M. hyosynoviae may produce arthritis in fattening pigs.  相似文献   

9.
Microbiological and serological studies on caprine pneumonias in Oman   总被引:9,自引:0,他引:9  
Eight of 10 typical cases of contagious caprine pleuro-pneumonia in Oman yielded strain F38-like mycoplasmas from the lungs in high titre, but no other mycoplasmas: both negative animals had been treated with tylosin shortly before death. Among 21 other lungs examined three of six cases of acute pneumonia yielded Mycoplasma ovipneumoniae; one also yielded M capricolum. M ovipneumoniae was also isolated from all eight cases of chronic pneumonia sampled from an abattoir, and from the lungs of three animals which died without overt signs of pneumonia. A single isolate of M arginini and three of unidentified mycoplasmas were also obtained from goats with and without pneumonia. Various bacterial species were isolated, none of which predominated. Antibodies to M mycoides subspecies capri (M m capri) and strain F38 were detected in sera from eight different sources. Assuming titres of 1 in 40 or more as positive in the indirect haemagglutination test used, 29 per cent of 422 serum samples had antibodies to M m capri alone, 2.6 per cent to strain F38 alone and 3.6 per cent to both organisms. These results confirm the presence of F38-like mycoplasmas in Oman, and indicate also widespread infection with M m capri. The role of the latter in caprine pneumonias in Oman requires elucidation.  相似文献   

10.
猫血巴尔通体研究概况   总被引:2,自引:0,他引:2  
猫血巴尔通体是引起猫发生传染性贫血的病原之一,在分类学上归属于立克次体目、无形体科.最近有很多新的研究指出这类病原体应归属于支原体目,"血巴尔通体"和"附红细胞体"也应该合称为"血营养性支原体"(Hemotrophic mycoplasmas).猫血巴尔通体作为血营养性支原体的重要代表,己经被广泛深入地研究,文章对其病原学、流行病学、发病机制、防治等方面的研究成果进行回顾与总结,以期对本病有进一步认识,对其他血营养性支原体的研究提供参考.  相似文献   

11.
ECOLOGY OF MYCOPLASMAS IN CLINICALLY HEALTHY CATS   总被引:1,自引:0,他引:1  
Mycoplasmas were isolated from various sites and organs of a series of 319 clinically healthy cats. They include M. felis, M. gateae, M. Arginini, A. laidlawii, feline ureaplasmas, M. pulmonis, M. arthritidis, and M. gallisepticum. In addition, there were 10 strains of mycoplasmas which could not be identified with the specific antiserums by growth inhibition tests. Antibody against M. felis was demonstrated by haemagglutination-inhibition and complement-fixation tests in cats which were over 6 months of age. However, no such antibody against M. felis was detected in animals which were less than 6 months old. No antibody against A. laidlawii, M. gateae, M. arginini and feline ureaplasmas was demonstrated by the same serological methods. The significance of these mycoplasmas in cats is described.  相似文献   

12.
Chlamydiae are an important cause of acute and chronic conjunctivitis in cats. Until recently, only one organism was thought to infect cats, Chlamydophila felis (previously Chlamydia psittaci var. felis). Recently, other Chlamydia-like organisms belonging to the family Parachlamydiaceae, which comprises organisms that reside and proliferate within free-living amoeba, have been identified in cats with neutrophilic and eosinophilic conjunctivitis. The relative importance of these organisms and their amoebic hosts requires investigation. There is also weak evidence that chlamydiae may also be capable of causing reproductive tract disease and lameness in cats. Diagnosis of chlamydial conjunctivitis requires use of specialized culture techniques or the polymerase chain reaction. The antibiotic of choice to treat these infections is doxycycline; azithromycin is less effective. All cats in the household should be treated simultaneously. The zoonotic potential of these organisms appears low, but some precaution is warranted when handling affected cats.  相似文献   

13.
Abstract: The red cell parasites formerly known as Haemobartomlla and Eperythrozoon spp have been reclassified as hemotrophic mycoplasmas (hemoplasmas) based on strong phylogenetic evidence and 16S ribosomal RNA gene sequences. The latter form the basis for polymerase chain reaction assays used to detect infection. Candidatus designation was given to incompletely characterized species. Like other mycoplasmas, hemoplasmas are small epicellular parasites that lack a cell wall and are susceptible to tetracyclines; their circular, double-stranded DNA encodes only those gene products essential for life. Diseases caused by infection with hemoplasmas range from overt life-threatening hemolytic anemia to subtle chronic anemia, ill-thrift, and infertility. In addition, the organisms may act as cofactors in the progression of retroviral, neoplastic, and immune-mediated diseases. Intimate contact of hemoplasma organisms with RBCs leads to cell injury through immune-mediated and other mechanisms that have not yet been defined. Despite an intense immune response and even with antibiotic treatment, infected animals probably remain chronic carriers after clinical signs have resolved.  相似文献   

14.
Toxoplasmosis.     
Toxoplasmosis in dogs and cats can cause chorioretinitis, anterior uveitis, or both. Ocular lesions are a common manifestation of generalized toxoplasmosis. The prevalence of toxoplasmosis as a cause of idiopathic anterior uveitis in cats is not clear, although there is a significant association between exposure to T. gondii and feline anterior uveitis. The pathogenesis of ocular toxoplasmosis may be different in humans and cats, and the anterior uveitis may represent a type of immune-mediated inflammation. A diagnosis is made by observing compatible clinical findings and obtaining supportive findings on serologic tests. Despite improved diagnostic techniques, including determination of IgM class antibodies and PCR testing, definitive diagnosis of ocular toxoplasmosis remains a challenge. Topical anti-inflammatory therapy should be used in cats with anterior uveitis, a positive serum titer, and no concurrent systemic signs. Systemic clindamycin should be given to cats with ocular and systemic signs and to cats with suggestive serology and idiopathic anterior uveitis that fails to respond to topical therapy alone.  相似文献   

15.
OBJECTIVE: To identify the prevalence of DNA of Mycoplasma haemofelis; 'Candidatus Mycoplasma haemominutum'; Anaplasma phagocytophilum; and species of Bartonella, Neorickettsia, and Ehrlichia in blood of cats used as blood donors in the United States. DESIGN: Prospective study. ANIMALS: 146 cats that were active blood donors. PROCEDURES: Environmental history was requested for each blood-donor cat from which a blood sample (mixed with EDTA) was available. Polymerase chain reaction assays capable of amplifying the DNA of the microorganisms of interest following DNA extraction from blood were performed. RESULTS: Overall, DNA of one or more of the infectious agents was detected in blood samples from 16 of 146 (11%) feline blood donors. Twenty-eight laboratory-reared cats housed in a teaching hospital had negative results for DNA of all organisms investigated. The DNA of at least 1 infectious agent was amplified from blood samples collected from 16 of 118 (13.6%) community-source cats; assay results were positive for 'Candidatus M haemominutum,' M haemofelis, or Bartonella henselae alone or in various combinations. Of the community-source cats allowed outdoors (n = 61) or with known flea exposure (44), DNA for a hemoplasma or B henselae was detected in 21.3% and 22.7%, respectively. CONCLUSIONS AND CLINICAL RELEVANCE: When community-source cats, cats allowed outdoors, or cats exposed to fleas are to be used as blood donors, they should be regularly assessed for infection with M haemofelis, 'Candidatus M haemominutum,' and Bartonella spp, and flea-control treatment should be regularly provided.  相似文献   

16.
Mycoplasma is the common name for the smallest free-living microorganisms, the Mollicutes. Mycoplasma hyopneumoniae is of great importance in veterinary medicine, causing enzootic pneumonia in pigs. M hyorhinis can cause polyserositis and may cause pneumonia in piglets. Oligonucleotides complementary to variable regions of 16S rRNA from these mycoplasmas were designed and used as probes for detection and identification of these mycoplasmas. The probe complementary to 16S rRNA of M hyorhinis gave a very weak cross-hybridisation with M hyosynoviae in filter hybridisation experiments, but not with any of the other porcine mycoplasmas tested. Three oligonucleotide probes complementary to M hyopneumoniae 16S rRNA were tested. One of the probes (Mhp6/30) was found to be specific to M hyopneumoniae, but the other two gave cross-hybridisation with M flocculare. Using the Mhp6/30 probe in direct filter hybridisation experiments, it proved possible to detect M hyopneumoniae in lung biopsies from experimentally infected pigs.  相似文献   

17.
This paper concerns the taxonomic status of the F38-like group (MacOwan), a prime determinant of contagious caprine pleuropneumonia (CCPP). Extensive biochemical and serological investigations on strain F38 are reported. Some complex serological relationships with other mycoplasma species are revealed. The results, taken in conjunction with earlier published work on geno-typic characters, lead to the conclusion that final classification of these organisms should await further comparative studies of a number of field strains with a related group of strains classified as M. capri-colum.The characterization of F38 confirms its partial relationship to the “M. mycoides group” of ovine/caprine/bovine mycoplasmas, and has also revealed a very close phenotypic relationship to the bovine mycoplasma serogroup 7, a finding of potential diagnostic and epidemiological importance.Key words: mycoplasmas, classification, F38-like group  相似文献   

18.
We have examined the presence of hemoplasmas, hemotropic mycoplasmas, among domestic cats (Felis catus) in Japan by using a species specific PCR, and found 'Candidatus Mycoplasma turicensis', a recently recognized hemoplasma species. A total of 60 feline blood samples collected in 2004 and 2005 were subjected to PCR amplification for the detection of Mycoplasma haemofelis, 'Candidatus Mycoplasma haemominutum' and 'Candidatus Mycoplasma turicensis'. Six blood samples collected from domestic cats were found infected with the 'Candidatus M. turicensis'. All of them are also infected with other species of hemoplasmas, M. haemofelis and/or 'Candidatus M. haemominutum'. This is the first to demonstrate 'Candidatus M. turicensis' infections among cat population in Japan.  相似文献   

19.
Iron is essential to virtually all living organisms and is integral to multiple metabolic functions. The most important function is oxygen transport in hemoglobin. Iron deficiency anemia in dogs and cats is usually caused by chronic blood loss and can be discovered incidentally as animals may have adapted to the anemia. Severe iron deficiency is characterized by a microcytic, hypochromic, potentially severe anemia with a variable regenerative response. Iron metabolism and homeostasis will be reviewed, followed by a discussion of diagnostic testing and therapeutic recommendations for dogs and cats with iron deficiency anemia.  相似文献   

20.
At least three haemotropic mycoplasmas have been recognized in cats: Mycoplasma haemofelis (Mhf), 'Candidatus Mycoplasma haemominutum' (CMhm) and 'Candidatus M. turicensis' (CMt). The latter was originally identified in a Swiss pet cat with haemolytic anaemia and shown to be prevalent in domestic cats and wild felids worldwide using molecular methods. So far, there has been no confirmatory morphological evidence of the existence of CMt presumably due to low blood loads during infection while CMhm has only been characterized by light microscopy with discrepant results. This study aimed to provide for the first time electron microscopic characteristics of CMt and CMhm and to compare them to Mhf. Blood samples from cats experimentally infected with CMt, CMhm and Mhf were used to determine copy numbers in blood by real-time PCR and for transmission and scanning electron microscopy. High resolution scanning electron microscopy revealed CMt and CMhm to be discoid-shaped organisms of 0.3 μm in diameter attached to red blood cells (RBCs). In transmission electron microscopy of CMt, an oval organism of about 0.25 μm with several intracellular electron dense structures was identified close to the surface of a RBC. CMhm and CMt exhibited similar morphology to Mhf but had a smaller diameter. This is the first study to provide morphological evidence of CMt thereby confirming its status as a distinct haemoplasma species, and to present electron microscopic features of CMhm.  相似文献   

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