From contamination to infective endocarditis-a population-based retrospective study of Corynebacterium isolated from blood cultures.

Corynebacterium is a genus that can contaminate blood cultures and also cause severe infections like infective endocarditis (IE). Our purpose was to investigate microbiological and clinical features associated with contamination and true infection. A retrospective population-based study of Corynebacterium bacteremia 2012-2017 in southern Sweden was performed. Corynebacterium isolates were species determined using a matrix-assisted laser desorption/ionization-time-of-flight mass spectrometry (MALDI-TOF MS). Patient were, from the medical records, classified as having true infection or contamination caused by Corynebacterium through a scheme considering both bacteriological and clinical features and the groups were compared. Three hundred thirty-nine episodes of bacteremia with Corynebacterium were identified in 335 patients of which 30 (8.8%) episodes were classified as true infection. Thirteen patients with true bacteremia had only one positive blood culture. Infections were typically community acquired and affected mostly older males with comorbidities. The focus of infection was most often unknown, and in-hospital mortality was around 10% in both the groups with true infection and contamination. Corynebacterium jeikeium and Corynebacterium striatum were significantly overrepresented in the group with true infection, whereas Corynebacterium afermentans was significantly more common in the contamination group. Eight episodes of IE were identified, all of which in patients with heart valve prosthesis. Six of the IE cases affected the aortic valve and six of seven patients were male. The species of Corynebacterium in blood cultures can help to determine if a finding represent true infection or contamination. The finding of a single blood culture with Corynebacterium does not exclude true infection such as IE.

Induction of Necrosis in Human Macrophage Cell Lines by Corynebacterium diphtheriae and Corynebacterium ulcerans Strains Isolated from Fatal Cases of Systemic Infections.

When infecting a human host, Corynebacterium diphtheriae and Corynebacterium ulcerans are able to impair macrophage maturation and induce cell death. However, the underlying molecular mechanisms are not well understood. As a framework for this project, a combination of fluorescence microscopy, cytotoxicity assays, live cell imaging, and fluorescence-activated cell sorting was applied to understand the pathogenicity of two Corynebacterium strains isolated from fatal cases of systemic infections. The results showed a clear cytotoxic effect of the bacteria. The observed survival of the pathogens in macrophages and, subsequent, necrotic lysis of cells may be mechanisms explaining dissemination of C. diphtheriae and C. ulcerans to distant organs in the body.

Recombinant M. bovis BCG expressing the PLD protein promotes survival in mice challenged with a C. pseudotuberculosis virulent strain.

The aim of this study was to evaluate the survival of mice inoculated with M. bovis BCG Pasteur recombinant expressing the PLD protein and challenged with a C. pseudotuberculosis virulent strain. Four groups were immunized with a sterile 0.9% saline solution (G1), 106 CFU of M. bovis BCG Pasteur (G2), 106 CFU of M. bovis BCG/pld (G3) or 106 CFU of M. bovis BCG/pld with a booster with rPLD (G4) and challenged with 104 CFU of C. pseudotuberculosis MIC-6 strain. The highest survival rate of 88% was observed in G4, followed by 77% in G3 and 66% in G2. A significant statistical difference was observed in the levels of cytokines IFN-γ and IL-10 in vaccinated groups (G3 and G4) when compared with the control group (G1) (p < 0.05). The results seem promising as the recombinant vaccine elicited a cellular immune response and provided significant survival after a high virulent challenge.

A novel experimental platform for toxigenic and non-toxigenic Corynebacterium ulcerans infection in mice.

Corynebacterium ulcerans is a zoonotic pathogen that can produce diphtheria toxin and causes an illness categorized as diphtheria in the European Union because its clinical appearance is similar to that of diphtheria caused by Corynebacterium diphtheriae. Despite the importance of the pathogen in public health, the organism's mechanism of infection has not been extensively studied, especially in experimental animal models. Therefore in the present study we constructed an intranasal infection system for mice. Mice are insensitive to diphtheria toxin and this has the advantage of excluding the cytotoxic effect of the toxin that might interfere with the analysis of the early stage of infection. Both the toxigenic and non-toxigenic C. ulcerans strains were capable of killing mice within 3 days after inoculation at 10(7) colony-forming units per mouse. In experimentally infected animals, C. ulcerans was detected in the respiratory tract but not in the intestinal tract. The bacterium was also detected in peripheral blood and it disseminated into the lung, kidney and spleen to produce a systemic infection. This experimental infection system provides a platform for analyzing the virulence of C. ulcerans in future studies.

Proportional mortality: A study of 152 goats submitted for necropsy from 13 goat herds in Quebec, with a special focus on caseous lymphadenitis.

The objectives of this study were to determine the main causes of mortality, with a special focus on caseous lymphadenits as a cause of death or wasting in caprine herds from Quebec. Goats (n = 152) from 13 herds were submitted for necropsy; the cause of mortality, and the presence, location, and cause of abscesses (if present) were recorded. Proportional mortalities were distributed as: Clostridium perfringens type D enterotoxemia (17.1%), pneumonia (13.8%), paratuberculosis (10.5%), listeriosis (6.6%), pregnancy toxemia (5.3%), caprine arthritis-encephalitis (4.6%), and caseous lymphadenitis (3.9%). Caseous lymphadenitis was diagnosed in 24.3% of the submitted goats, but was not a major cause of wasting or mortality. Abscesses were localized internally in 54.1% of the cases. Paratuberculosis was diagnosed in 29 goats (16 as cause of death) and was considered a major cause of wasting and/or mortality.

Mortalité proportionnelle: Une étude de 152 chèvres soumises pour nécropsie provenant de 13 élevages caprins du Québec, avec une attention particulière à la lymphadénite caséeuse. Les objectifs de cette étude furent de déterminer les principales causes de mortalité avec une attention particulière à la lymphadénite caséeuse comme cause de mortalité ou de dépérissement chez les chèvres du Québec. Cent-cinquante-deux chèvres provenant de 13 élevages différents ont été soumises pour nécropsie; la cause de mortalité, la présence d'abcès, leur localisation et leur cause (s'il y a lieu) furent compilées. Les mortalités proportionnelles furent distribuées ainsi : entérotoxémie de type D (17,1 %), pneumonie (13,8 %), paratuberculose (10,5 %), listériose (6,6 %), toxémie de gestation (5,3 %), arthrite-encéphalite caprine (4,6 %) et lymphadénite caséeuse (3,9 %). La lymphadénite caséeuse a été diagnostiquée chez 24,3 % des chèvres soumises, mais sans être une cause majeure de dépérissement et de mortalité. Les abcès étaient localisés de façon interne dans 54,1 % des cas. Au total, la paratuberculose a été diagnostiquée chez 29 chèvres (16 en étant décédées) et fut considérée comme une cause majeure de dépérissement et/ou de mortalité.(Traduit par les auteurs).

Corynebacterium jeikeium endocarditis: a systematic overview spanning four decades.

Skin flora is an important source of microorganisms that cause infective endocarditis. While staphylococcal and beta-hemolytic streptococcal species are well-recognized components of skin flora that can cause infective endocarditis, other skin flora rarely produce endocardial infection. One species of Corynebacterium has received the most attention, Corynebacterium jeikeium. This bacterium, a gram-positive rod that is a strict aerobe, is known to cause mechanical prosthetic valve infection and vancomycin is generally required for treatment of this multidrug-resistant organism. Following treatment of an unusual case of bioprosthetic valve endocarditis due to C. jeikeium, a Medline search for English-language articles published from January 1966 to October 2004 was performed. Reports of C. jeikeium endocarditis cases with culture of either blood or cardiac surgery tissue samples positive for C. jeikeium and with clinical and echocardiographic findings of infective endocarditis were reviewed. Clinical data and results of diagnostic procedures were examined. All 38 patients with C. jeikeium endocarditis reported in the literature had at least one predisposing condition for the development of infective endocarditis. The majority of patients (74%) had involvement of a prosthetic heart valve. The mortality attributed to C. jeikeium endocarditis was 33% and was similar in patients who did and did not undergo valve replacement. This relatively high mortality rate mandates that clinicians be aware of this rare endocardial infection. C. jeikeium is a rare cause of endocarditis and it more commonly infects prosthetic valves. Careful scrutiny is required when C. jeikeium is isolated from a blood culture, particularly in patients with underlying prosthetic cardiac valves.

Morbidity and mortality associated with Arcanobacterium pyogenes in a group of captive blackbuck (Antilope cervicapra).

Arcanobacterium pyogenes was associated with necrotizing pneumonia; mandibular osteomyelitis; peritonitis; and hepatic, pulmonary, renal, and subcutaneous abscessation in a group of captive blackbuck (Antilope cervicapra). Males were more frequently (73.3%) affected than females. Infection with A. pyogenes was fatal or necessitated euthanasia in 15 of 16 (93.7%) cases. Deaths associated with A. pyogenes occurred most frequently (60%) during winter.

Fatal septic shock caused by Corynebacterium D2.

BACKGROUND: Septic shock remains one of the leading causes of mortality in critically ill patients. Optimal management depends on prompt diagnosis with identification of the causative organisms to allow appropriate antibiotic therapy. PATIENT: We report the first case of septic shock caused by Corynebacterium D2, a micro-organism that can cause encrusted cystitis and pyelitis of transplanted kidneys or, more rarely, native kidneys. Diagnosis rests on identification of risk factors, positive urine cultures, and computed tomography results. Despite optimal treatment our patient died with persistent encrusted pyelitis. CONCLUSIONS: Corynebacterium D2 is known to cause chronic inflammation of the bladder and proximal urinary tract but can also cause severe septic shock in immunocompetent patients.

Mortality from grossly encrusted bilateral pyelitis, ureteritis, and cystitis by Corynebacterium group D2.

This is the first report of death due to gross encrustations of the entire upper urinary tract and bladder by Corynebacterium group D2 in a man with no history of renal transplantation or prolonged catheterizations. This case demonstrates that debilitated patients with a prior endoscopic procedure are at risk for this disease process. Prolonged treatment with appropriate antibiotics, acidification of the urine, and removal of crusts is essential for proper management.

[Surgery of endocarditis in the drug dependent and HIV patient. A prospective comparison with conservative treatment]. / Chirurgie der Endokarditis beim Drogensüchtigen und HIV-Patient. Ein prospektiver Vergleich mit der konservativen Behandlung.

The incidence of infective endocarditis in drug addicts is increasing with the spreading of intravenous drug abuse. The tricuspid valve is the most commonly involved valve followed by the mitral valve. We evaluated prospectively 22 patients with a mean age of 23 years, presenting with addiction-associated endocarditis endocarditis and referred to our institution during a three-year period. The tricuspid valve was involved in 13 instances, mitral valve in 4, mitral plus tricuspid valve in 5 patients and aortic valve in 1 case. Staphylococcus aureus was the most frequent infective organism (15x), followed by Streptococci (4x), Corynebacteria (2x) and one case with a mixed infection. Six patients were positive for an HIV-infection and 17 had evidence for a chronic viral hepatitis. Ten patients (3 of them HIV-seropositive) were treated surgically. Resection of the tricuspid valve with (1x) or without replacement (4x), resection of vegetations and valve repair (2x), mitral valve replacement (2x), aortic valve replacement (1x) were performed. In case of tricuspid endocarditis, the decision whether to proceed with resection, repair or replacement with a bioprosthesis was taken according to valve pathology and the psycho-social situation of the patient. When the vegetations involved only one leaflet and could be removed easily, vegetectomy with annuloplasty or with repair using autologous pericardium was performed. Valvulectomy without replacement was the chosen method for those where persistent or recurrent drug abuse could not be excluded. A bioprosthesis was inserted when the tricuspid valve was completely destroyed and there was a proven abstinence from drugs over a period of several weeks preoperatively.(ABSTRACT TRUNCATED AT 250 WORDS)

Diphtheria with a difference--a rare Corynebacterium fatality with associated apoptotic cell death.

A case of infection with Corynebacterium ulcerans (C. ulcerans), resulted in the sudden death of a previously healthy 73-year-old woman. Death from Corynebacterium diphtheriae (C. diphtheriae) infection is well-documented. Fatalities following infection with C. ulcerans are unreported; this would appear to be the first documented death due to such infection.

[Findings of Corynebacterium equi Magnusson 1923 in connection with foal mortality in the Eastern Bohemia Region]. / Nález Corynebacterium equi Magnusson 1923 v souvislosti s úhyny hríbat ve Východoceském kraji.

A case history of mass foal disease which affected ten of the total stock of 50 foals and killed eight is described. The disease was characterized by respiratory disorders and extensive pneumonias with abscess formation, metastatic abscesses in mesenterial lymph nodes and in other organs. As a result of the examination of two dead foals and three nasal smears from diseased animals, gram-positive bacteria were isolated from the lungs, pulmonary and abdominal abscesses and the nasal smears of the affected foals; with their cultivation, morphological and biochemical characteristics these bacteria correspond to the species Corynebacterium equi. The properties of the four isolated strains were compared with the most important literary data.

Enhanced resistance to Corynebacterium pseudotuberculosis infections associated with reduced serum immunoglobulin levels in levamisole-treated mice.

The effect of levamisole (1-2,3,5,6-tetrahydro-6-imidazo[2,1-b]thiazole monohydrochloride) treatment on the course of a Corynebacterium pseudotuberculosis infection and the ability of either vaccinated or unvaccinated randomly bred mice to resist challenge were investigated. It was found that either a double treatment of levamisole administered with or without a sublethal inoculation of C. pseudotuberculosis or a single treatment of levamisole alone had a significant effect on the ability of mice to resist challenge with virulent C. pseudotuberculosis. This prolonged, enhanced nonspecific and specific resistance was associated with a quantitative reduction in the geometric mean serum immunoglobulin levels, with the immunoglobulin G2 and immunoglobulin A levels being more severely affected. As the enhanced nonspecific resistance to C. pseudotuberculosis was associated with depressed serum immunoglobulin levels in the mice pretreated with levamisole alone, it was suggested that the cell-mediated immunity may play a more important role than the humoral immunity in the resistance to C. pseudotuberculosis infection.