Pathogenesis of Erysipelothrix piscisicarius infection in tiger barbs (Puntigrus tetrazona)

Erysipelothrix piscisicarius is an emerging bacterial pathogen and the aetiologic agent of piscine erysipelosis, a recently recognized disease of ornamental fish. However, little is known regarding the dynamics of infection in fish. The purpose of this study was to gain a better understanding of the pathogenesis of piscine erysipelosis in the tiger barb (Puntigrus tetrazona) by investigating tissue tropisms and responses to bacterial dissemination following immersion challenge with a virulent strain recovered from diseased fish. The challenge resulted in 83% mortality by day 16. Erysipelothrix piscisicarius DNA was first detected in the skin using quantitative PCR, and bacteria were visualized in association with microscopic lesions on day 4. By day 8, E. piscisicarius DNA was further detected in intestines, hearts, spleens, gills and skin; parenchymal organs were largely spared. The data suggest a primary cutaneous portal of entry and tropism for collagenous tissues, particularly those within vascular walls. Initial spread occurs directly from the dermis into interstitial areas of skeletal muscle, then centrally to the peritoneum and coelomic cavity following collagenous tissue pathways. Although histopathology revealed widespread bacterial dissemination over time, the severity of skin and muscle lesions with high levels of bacterial DNA identifies these tissues as primary targets of infection.

Fatal Erysipelothrix rhusiopathiae septicemia in two Atlantic dolphins (Stenella frontalis and Tursiops truncatus)

We describe gross, histopathologic, ultrastructural, immunohistochemical, and microbiologic features of acute septicemia by Erysipelothrix rhusiopathiae in an Atlantic spotted dolphin Stenella frontalis and an Atlantic bottlenose dolphin Tursiops truncatus. Generalized lymphadenomegaly and widespread hemorrhages were the most consistent macroscopic findings. Tricavitary effusion and icterus were noted in one individual. Histologically, all organs examined showed numerous variably sized bacillary bacterial emboli (Gram-positive; Ziehl-Neelsen-negative), typically associated with systemic congestion, edema, hemorrhages, and fibrinocellular thrombi. These bacteria were frequently intravascular, either extracellular or intramonocytic/macrophagic, and to a lesser extent, free within the interstitium of parenchymal organs. In both cases, microbiological analysis yielded E. rhusiopathiae. A primary anti-E. rhusiopathiae antibody created in mice from one of the strains isolated allowed positive immunohistochemical detection. Electron microscopy and dual immunohistochemistry with lysozyme and MAC387 antibodies confirmed the intramacrophagic location of the bacilli. E. rhusiopathiae, a known multispecies and zoonotic agent, should be considered as a potential etiologic agent in septicemia cases in free-ranging individuals of these dolphin species.

Erysipelothrix rhusiopathiae pneumonia in an immunocompetent patient

Erysipelothrix rhusiopathiae is a Gram-positive bacillus that causes infections primarily in animals. In humans, this bacterium usually causes localized cutaneous infections called erysipeloid. Here we report a case of pneumonia with isolation of E. rhusiopathiae from bronchoalveolar lavage and sputum. To our knowledge, this is the first report of a pneumonia case caused by E. rhusiopathiae confirmed by culture.

An autopsy case of Erysipelothrix rhusiopathiae endocarditis

A 58-year-old man was admitted to our hospital with fever. The vegetation was confirmed by echocardiography on the tricuspid valve and Erysipelothrix rhusiopathiae was isolated by blood culture. The patient died due to heart failure, and tricuspid valve vegetation was confirmed on autopsy and the sample of Gram's staining showed gram-positive microcolonies. Although about 60 cases of E. rhusiopathiae endocarditis have been reported, Japanese cases are extremely rare.

Investigations on the Pathogenicity of Erysipelothrix rhusiopathiae in Laying Hens

Erysipelas was diagnosed in 1998 from 34-wk-old laying hens in a free range flock in Germany. Erysipelothrix rhusiopathiae of serotype 1 was cultured from internal organs of the affected birds. This article describes the pathogenicity of the field isolate of E. rhusiopathiae in experimentally infected specific pathogen-free (SPF) laying hens. Three experiments were performed with SPF chickens inoculated at 17, 27, and 37 wk of age by either intramuscular (IM) or oral route. Inoculated birds were observed for 14 days. The highest mortality rates occurred in older birds, with 100% mortality observed in the 37-wk-old birds inoculated IM, 60% mortality reported in the younger 27-wk-old birds, and no mortality in the 17-wk-old age group. In the orally infected 27-wk-old birds, 40% mortality was detected, whereas no mortality was observed in the oldest birds by the same route. The results of the experiments support the contention that older birds are more sensitive to infection than younger birds and that mortality in laying hens is age related and dependent on the route of infection.

Erysipelothrix rhusiopathiae septicemia in a Laughing kookaburra (Dacelo novaeguineae)

Erysipelothrix rhusiopathiae (E. rhusiopathiae) septicemia was demonstrated in a captive Laughing kookaburra (Dacelo novaeguineae). The bird died after a 2-week period of weakness and weight loss. At necropsy, the bird was emaciated and had reddened and wet lungs. Microscopic lesions were limited to hepatic and pulmonary congestion with focal thrombosis. Erysipelothrix rhusiopathiae was isolated by routine bacterial culture from several organs. Further characterization of the isolate by pulsed-field gel electrophoresis indicated that the isolate has a new genotype pattern 3A(III), which is 91.7% homologous to an E. rhusiopathiae that was isolated from a pig in 2001 and 88% homologous to an isolate recovered in 2000 from a turkey with septicemia. This is the first report of E. rhusiopathiae-induced septicemia in a kookaburra.

Erysipelothrix septicemia in a little blue penguin (Eudyptula minor)

On June 25, 2002, aquarium veterinarians treated a 5-year-old, male little blue penguin (Eudyptula minor) that was acutely recumbent and dull, with inappetence of 24-hour duration. The penguin died within 10 minutes of presentation despite emergency resuscitation efforts. Gross pathologic findings consisted of pulmonary congestion and intestinal hemorrhage. Histopathologic findings included necrosis of tips of intestinal villi, increased numbers of mononuclear cells in pulmonary interstitium and hepatic sinusoids, and gram-positive bacteria in systemic microvasculature. Transmission electron microscopic examination revealed short gram-positive bacilli located in lumina of glomerular capillaries and in cytoplasm of mononuclear phagocytic cells in the lung and liver. Erysipelothrix rhusiopathiae was recovered from the lung, liver, and intestine by bacteriologic culture. Amplicons from polymerase chain reaction (PCR) tests using Erysipelothrix genus-specific primers and total genomic DNA extracted from formalin-fixed, paraffin-embedded tissue sections of lung and intestine demonstrated 99% nucleotide sequence identity with 16S small-subunit ribosomal DNA of E. rhusiopathiae and E. tonsillarum. The source of infection was speculated to be fish in the diet; however, repeated attempts to detect Erysipelothrix spp. from the mucous layer of food fish using bacteriologic culture and PCR were unsuccessful. This is the first report of erysipelas in a captive aquatic bird. Details of the isolation of E. rhusiopathiae and the application of molecular testing to identify Erysipelothrix DNA in formalin-fixed, paraffin-embedded tissue sections are given.

Chronic monoarthritis of the knee in systemic lupus erythematosus

We describe a middle-aged lady with systemic lupus erythematosus who presented with chronic left knee monoarthritis without constitutional symptoms. The histology of synovial tissue taken at arthroscopy showed acute inflammation and Erysipelothrix rhusiopathiae, identified with some difficulty, was isolated from the enrichment broth only. Blood cultures were negative. Her history revealed significant exposure to pond fish. She responded well to intravenous penicillin and remains well 12 months later.

Erysipelothrix rhusiopathiae septic arthritis

We describe herein the case of a man with Erysipelothrix rhusiopathiae septic arthritis and possible infective endocarditis. This is the first report in the English-language medical literature of septic arthritis caused by this organism.

Diagnosis by polymerase chain reaction of Erysipelas septicemia in a flock of ring-necked pheasants

A flock of 810 pheasants experienced 6.2% mortality over 6 days. Affected birds were weak and lethargic for up to 24 hr before death. Examined birds were thin, and gross lesions consisted of thick opaque crops and cecal cores. Histologically, there was capillariasis of the crop and multifocal ulcerative typhlitis with Heterakis spp. infection, and numerous systemic intravascular monocytes were filled with clusters of blue rod-shaped organisms. The organisms were gram-positive bacilli by Brown and Brenn staining and ultrastructural analysis. Liver bacterial cultures were negative for pathogenic bacteria. Erysipelas septicemia was diagnosed by an Erysipelothrix species-specific polymerase chain reaction method with the substrate DNA isolated from formalin-fixed, paraffin-embedded liver.

Erysipelothrix rhusiopathiae: an uncommon but ever present zoonosis

Erysipelothrix rhusiopathiae is an important animal pathogen with a worldwide distribution, yet this zoonotic infection is rarely reported in humans. Three cases of E. rhusiopathiae infection, which illustrate the varied clinical presentations of this pathogen in humans, are presented together with the pathological findings and treatment regimens.

Fatal Erysipelothrix rhusiopathiae septicemia in a captive Pacific white-sided dolphin (Lagenorhyncus obliquidens)

One male of a group of seven Pacific white-sided dolphins (Lagenorhynchus obliquidens) died after a brief period of nonspecific clinical signs. Four beluga whales (Delphinapterus leucas) and four harbor seals (Phoca vitulina) were managed in the same water system. Gross examination of the dolphin revealed only moderately enlarged mesenteric lymph nodes. Histopathology revealed small to massive numbers of gram-positive bacilli, usually intravascular, in all tissues. Bacteria were both extracellular and present in macrophages, monocytes, and neutrophils. Aerobic bacterial culture of lung, liver, kidney, and spleen yielded pure cultures of Erysipelothrix rhusiopathiae. Based on clinical course, histopathology, and bacteriology, a diagnosis of acute erysipelas septicemia was made. None of the other cetaceans or pinnipeds exhibited clinical signs.

Disseminated intravascular coagulation in chickens inoculated with Erysipelothrix rhusiopathiae

In a first experiment, 28 specific pathogen-free chickens aged 3 weeks showed clinical signs 1 to 5 days after intramuscular inoculation with Erysipelothrix rhusiopathiae. Twelve of 28 birds died 2 to 4 days after inoculation. Macroscopically, the liver, spleen and kidneys were seen to be enlarged and congested. Histologically, fibrinous thrombus formation, seen in the hepatic sinusoids, renal glomerular capillaries and small pulmonary blood vessels, was a characteristic feature. In addition, the liver showed marked congestion, increase of mononuclear cells and heterophils in the sinusoids, hyperplasia of sinusoidal lining cells, and vacuolar changes in hepatic cells. The spleen showed fibrinous exudation of the lymphoid follicles and ellipsoids with lymphocytic depletion, and hyperplasia of ellipsoidal reticular cells. There was oedema, congestion and cellular infiltration in the interstitium of the kidney. The bursa of Fabricius and thymus showed marked lymphocytic depletion. In a second experiment, the blood chemical values (uric acid, glutamic-oxalacetic transaminase, lactate dehydrogenase and gamma-glutamyl transpeptidase) of birds inoculated intramuscularly with E. rhusiopathiae were significantly higher than those of uninfected controls. The blood prothrombin times and activated partial thromboplastin times of the inoculated group were significantly greater than those of the control group. The pathological and haematological findings demonstrated that E. rhusiopathiae induced disseminated intravascular coagulation in the chickens.

Non-purulent arthritis in Danish slaughter pigs. I. A study of field cases

The pathology and microbiology of non-purulent arthritis in Danish slaughter pigs were studied in order to draw up an updated picture of the disease. Samples of one or more joints, their regional lymph nodes and the heart were collected from 101 arthritic pigs, totalling 137 joints, 86 lymph nodes and 96 hearts (group I). For another selected group including 25 pigs (group II), the preliminary diagnosis of mycoplasmic arthritis, based on the appearance of the corresponding regional lymph node, was assessed versus the appearance of the joint fluid. A total of 44 samples were examined. More than 70% of all joint samples in both groups were sterile. Erysipelothrix rhusiopathiae was isolated from 7% of the joints and Mycoplasma hyosynoviae from 9%. A contamination flora was isolated in 17% of the samples. Very few of the lymph nodes (5%) were infected, and none of the hearts were. In group-II M. hyosynoviae was isolated from 8% of the joints. From the remainder the isolates were contamination flora or low numbers of non-specific bacteria. The gross pathological changes of the lymph nodes and joints of the E. rhusiopathiae cases differed notably from those of the M. hyosynoviae cases. The pathological features of the lymph nodes, in particular, were type specific. This suggests that these features may be used to differentiate between the two types of arthritis. Considering the high number of sterile samples, it is necessary to test this hypothesis in greater detail. A programme is outlined to elucidate the zoonotic and hygienic consequences of a proposed alternative handling and removal procedures for the two types of arthritis at slaughter.

Erysipelothrix rhusiopathiae, serotype 17, septicemia in moose (Alces alces) from Algonquin park, Ontario

Erysipelothrix rhusiopathiae septicemia was diagnosed in three of four moose found dead in Algonquin Provincial Park, Ontario, Canada, in the spring of 1989. Type 17 E. rhusiopathiae was isolated from liver, lung, kidney, and lymph nodes of affected animals, which were in poor body condition, and suffering hair loss associated with tick (Dermacentor albipictus) infestations. Microscopic lesions consisted of mild, multifocal, necrotizing myocarditis, sarcocystosis, and lymph node atrophy. The bacterium may have gained entry to these animals via ingestion of, or percutaneous exposure to, contaminated water, or possibly by the bites of ticks. Malnutrition and tick infestation may have predisposed the animals to infection by this opportunistic pathogen.

Changes in rat leukocyte populations in peripheral blood, spleen, lymph nodes, and synovia during Erysipelas bacteria-induced polyarthritis

Kinetics of leukocyte subsets were followed for several weeks in rats suffering from polyarthritis induced by experimental infection with erysipelas bacteria (Erysipelothrix rhusiopathiae, serovar 2, strain T28). A marked leukocytosis was found in peripheral blood, and, with some delay, in the synovia and draining lymph nodes of affected joints. In the lymphoid organs tested considerable blast formation of lymphoid cells with a paucity of polymorphonuclear granulocytes was found, while the latter represented the majority of leukocytes in acutely inflamed joints. Cells isolated from spleen showed only moderate and transient alterations in proportions of subpopulations during the first week after inoculation of erysipelas bacteria. In contrast, cells isolated from synovia of inflamed joints and draining lymph nodes displayed more intense and longer lasting alterations: In arthritic animals, the proportion of MHC class II-positive lymphocytes generally increased and remained elevated at least during the first three weeks of the disease. Spontaneous release of IL-2 from cells isolated up to 20 days post induction of the arthritis indicated a considerable activation of lymphocytes in vivo. Interestingly, with exception of synovia, the relative amount of T-lymphocytes including their major CD4+ and minor CD8+ subsets showed little alteration during the course of the disease. Much more pronounced were the rapidly and the extent the membrane Ig-positive B-lymphocytes increased in the synovia as well as in the lymph nodes. Thus, B-lymphocytes may be of particular relevance for elucidating pathomechanisms of erysipelas polyarthritis.

[Erysipelas in the roe deer--a case report]

An infection of a young male roe deer caused by Erysipelothrix rhusiopathiae with a pronounced thrombotic endocarditis in the left valves and focal necrosis in the septum of the heart leading to bacterial sepsis is described. Findings of this kind are extremely rare in roe deer. However, they document the wide host range, which is also illustrated by the numerous publications on such infections in other species.

Recognition of IL1-activated chondrocytes in porcine articular cartilage

A polyclonal antiserum has been raised against interleukin 1 (IL1)-induced epitopes on the surface of porcine articular chondrocytes. Using this antiserum in immunolocalization studies we have been able to identify individual chondrocytes in situ both in experimentally activated articular cartilage and in pathological tissue from pigs with induced polyarthritis.

Erysipelothrix rhusiopathiae: an occupational pathogen

Erysipelothrix rhusiopathiae is a nonsporulating, gram-positive, rod-shaped bacterium which was identified more than 100 years ago as the etiologic agent of swine erysipelas. Since then, it has been found to cause infection in several dozen species of mammals and other animals. Humans become infected through exposure to infected or contaminated animals or animal products. By far the most common type of human infection is a localized, self-limited cutaneous lesion, erysipeloid. Diffuse cutaneous and systemic infections occur rarely. Approximately 50 cases of endocarditis have been reported; all but one recent case have involved native valves. The organism may be isolated from biopsy or blood specimens on standard culture media. It is identified by morphology, lack of motility, and biochemical characteristics; identification may be confirmed by the mouse protection test. It is susceptible to penicillins, cephalosporins, erythromycin, and clindamycin, but it is often resistant to many other antibiotics, including vancomycin, a drug frequently used in empiric therapy for infections due to gram-positive bacteria.

Naturally occurring erysipelas in rats

Erysipelothrix rhusiopathiae was isolated from the main limb joints of two Sprague Dawley rats affected by spontaneous lesions of chronic fibrinopurulent polyarthritis, endocarditis and mycocarditis.

Isolation of Erysipelothrix rhusiopathiae from a red-tailed hawk (Buteo jamaicensis) with a concurrent pox virus infection

Erysipelothrix rhusiopathiae was isolated from the spleen, liver, lung, heart, kidney, and skin of a red-tailed hawk (Buteo jamaicensis) which had a concurrent avian pox virus infection. The hawk had been housed on a farm with domestic turkeys, providing a possible source of the E. rhusiopathiae.

[Morphologic studies of reactive changes in the joint cartilage in experimental erysipelas arthritis]

In experimentally Erysipelothrix rhusiopathiae-induced polyarthritis of pigs, important pathomechanisms of bacterial invasion of the articular cartilage matrix were studied. Furthermore, observations were made concerning inflammatory cartilage changes in the transitional zone of the distal femur condyle. The morphological changes were a loss of proteoglycans, proliferation and transformation of cartilage cells, compensatory formation of collagenous fibers progressing to cartilage fibrosis and pannus formation. As histology only represents a static picture, different methods are necessary to finally verify the dynamics of this process. It appears likely, that cartilage and pannus combined, and synergistically after fibroblastic transformation, produce a reparative scar in the area of cartilage alteration.

The role of cartilage canals in the pathogenesis of experimentally induced polyarthritis

Porcine articular cartilage from cases of experimentally induced Erysipelas polyarthritis, a comparative model of rheumatoid arthritis (RA) in man, was examined with different histological and immunohistochemical techniques. The preexisting canals in articular cartilage played a crucial role during the flooding and deposition of arthritogenic microorganisms deep into the cartilage matrix. Subsequently this vascularized tissue mediated the same inflammatory reactions in hyaline cartilage of young animals as seen in other connective tissues. However, these stereotypical responses to injury were modulated by the unique composition and structure of articular cartilage.

Intercellular network in articular cartilage of pigs with experimentally induced arthritis. I. Fact or artifact?

Porcine articular cartilage from cases of experimentally induced Erysipelas arthritis was examined with different histological techniques and by electron microscopy. A small percentage of specimens of osteoarthritic cartilage revealed an interlacunar network in the extracellular matrix. These "matrix-streaks" showed characteristic features of densely packed fibrillar elements and collagenous fibrils, as narrow bands connecting adjacent chondrocytes. In a given cartilage site the network had a constant pattern. It is hypothesized that the network formation is correlated with altered joint metabolism and represents regressive changes in cartilage matrix as a result of external mechanical forces. Using a variety of methods, the possibility of the network being an artifact of histological processing could virtually be ruled out. As there are so far only few and contradictory reports on the interlacunar network of articular cartilage, its precise biological significance remains to be established.

Experimental arteritis in young rats induced by Erysipelothrix rhusiopathiae

The acute phase of arteritis of the common iliac artery induced in young rats by the inoculation of viable Erysipelothrix rhusiopathiae (E. rhusiopathiae) was examined. Within three days post inoculation, cell infiltration was first detected in the periarterial tissue, extending centripetally to the outer two-thirds of the media. However, the inner third of the media and the intima were free from cell infiltration, and the media showed no degeneration. E. rhusiopathiae first invaded the periarterial tissue and the adventitia, thereafter, invaded the outer two-thirds of the media, but not the inner third of the media or the intima. Invasion by the bacteria preceded cell infiltration. Arteritis was not induced by heat killed bacteria or the supernate from the culture medium. The arteritis was produced preferentially in large or medium-sized muscular arteries. Immunofluorescence test by FITC-conjugated peanut lectin demonstrated the desialated sites by the effect of the neuraminidase produced by E. rhusiopathiae in the arterial region that were concomitant with the invasion of the bacteria. C3 was also detected along the adventitia of the artery. The results demonstrated that viable E. rhusiopathiae can induce arteritis of muscular arteries and that the neuraminidase produced by the bacteria may play a role in the pathogenesis.

A report of swine erysipelas in a litter of piglets

Out of a litter of 7 two-week old Landrace piglets, 6 developed cutaneous haemorrhages especially on the limbs and ears. Two of these piglets died within 24 hours of the haemorrhages appearing whilst the other 4 recovered following penicillin therapy. The histopathological lesions were centred around the smaller vessels of the dermis and hypodermis. These included hyperaemia, leukostasis and intravascular fibrin coagulation or thrombosis. Bacterial emboli were present within the vessels of the skin, spleen, liver and kidney and loose in the areolar tissue of the dermis and hypodermis. Other lesions included scattered but extensive dermal and hypodermal haemorrhages and a mild cellular infiltration of the dermis and hypodermis.

Postembedding immunohistochemical demonstration of antigen in experimental polyarthritis using plastic embedded whole joints

A method is presented for the immunohistochemical demonstration of antigens in whole undecalcified joints of small laboratory animals. With this method of tissue preparation, involving embedding in a medium mainly based on 2-hydroxyethyl methacrylate, preservation of antigenicity is satisfactory. Antigens can be demonstrated in 2 micron sections by either immunofluorescence or immunoperoxidase and an indirect technique. Therefore in addition to the morphological analysis of joint alterations in experimental polyarthritis, there is now an opportunity to trace the inciting antigen and to study in parallel the enzymatic equipment of the cells involved, using consecutive sections from a single block of tissue.

Endocarditis caused by Erysipelothrix rhusiopathiae in a dog

Bacterial endocarditis was diagnosed in a 4-year-old male German shorthaired Pointer with a 4-month history of shifting lameness and intermittent fever. The dog died in spite of treatment for progressive depression and dehydration. Blood cultures were positive for Erysipelothrix rhusiopathiae strain 7, which is known to be pathogenic for dogs. The clinical diagnosis was confirmed at necropsy.20

Pathology of experimental erysipelas in turkeys

Gross and histopathologic lesions were studied in 10 Broad-Breasted White turkeys with acute erysipelas induced experimentally. The gross pathologic features of the disease conformed very closely with descriptions in the literature (7). Histopathologic evaluation was concentrated on the inoculation site (skin), proventriculus, ileocecal area of the intestine, liver, spleen, kidney, lung, and heart. In all organs examined the dominant histopathologic alteration was vascular damage as evidenced by: generalized congestion, edema, focal hemorrhage, disseminated fibrin thrombi, and numerous bacterial aggregates either within fibrin thrombi or engulfed by cells of the reticuloendothelial system. Degenerative changes or overt necrosis of parenchymal cells were evident in liver, spleen, and kidney. The cellular inflammatory component of acute lesions was minimal. Heterophil and mononuclear leukocytic infiltrates were observed in scarified skin and, in turkeys surviving several days, in livers and hearts.

Effect of experimentally induced trichinellosis on the infection with Erysipelothrix rhusiopathiae in rats

Infection with Erysipelothrix rhusiopathiae in rats infested 20 days earlier with Trichinella spiralis developed more slowly, the clinical and pathoanatomic changes in the joints were expressed to a less extend, and the mortality rate was lower. The erythrocyte sedimentation rate, the precipitin formation and the phagocytic activity of the macrophages did not considerably change. Experiments carried out to elucidate this fact did not reveal any antigenic or antagonistic relationships between parasite and bacterium nor any protective effect of the host's serum. The inhibitory influence of corticosteroids on the defence forces was not completely manifested in the rats infested. This fact might be explained by interrelations depending both on the cycle of helminth development and on the non-specific immunological reactivity of the organism, the latter being stimulated by the helminth invasion.

[Erysipelothrix rhusiopathiae infections. General review of 31 cases of septicemia with endocarditis reported in the literature (author's transl)]

Erysipelothrix rhusiopathiae is widely distributed in nature (animal, soil). It is commonly known as the causative agent of cutaneous lesions called "erysipeloid of Rosenbach". Only 31 cases of bacterial endocarditis have been reported in the literature. The etiologic diagnosis of Esysipelothrix infection was established by the presence of bacteria in blood cultures or heart-valve cultures. Immunological study is unusual owing to the rapid course of the infection. The histologic observation of heart lesions corroborates the diagnosis. The patient's receptivity depends on his occupation, general health (importance of rheumatic heart disease), sex (male), age (from 40 to 60 years old), but also on the season (from July to October) and climate (temperate). With the exception of the few cases where it is possible to recognize a portal of entry of infection or the appearance of typical cutaneous manifestations, bacterial endocarditis due to Erysipelothrix presents a clinical picture similar to that of most other bacterial endocarditis. The antibiotic treatment is an association of penicillin-streptomycin, administered in large doses over a period of at least four weeks. In spite of intensive therapy, many patients died.