Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0004610 (bacteremia)
 13,199 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

A Gram-negative bacillus that defies identification was isolated from blood cultures of 17 patients with fever. Fifteen patients were male adults, and 14 patients had underlying diseases, including previous splenectomy in five, which impair host defenses against infection. Illnesses occurred in the summer and autumn in 14 cases and had been recently preceded by dog bites in 10 cases. Clincal syndromes included cellulitis in seven cases, primary bacteremia without localization in four, purulent meningitis in four, and endocarditis in three. Three patients died. The organism grows slowly on blood or chocolate agar in 10% CO, is oxidase- and catalase-positive, and is negative for nitrate reduction, indole production, and urease. It produces acid from glucose, lactose, and maltose. These features distinguish it from all previously described and classified bacteria. Furthermore, the epidemiologic features of the patients suggest that this organism is an opportunistic invader and may have an animal reservoir in nature.
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PMID:Unidentified gram-negative rod infection. A new disease of man. 83 7

Eleven patients were colonized or infected with diphtheroids identified as Corynebacterium xerosis. All the patients were compromised hosts by nature of their underlying disease and/or therapy. Two patients developed bacteremia following colonization of the respiratory tract with C. xerosis. Other patients were colonized at various sites, which included the respiratory tract, abdominal and thoracic wounds, amputated limb, and arterial-venous shunt. Distinctive features for the identification of C. xerosis include negative reactions for hemolysis, urease, and motility, and positive reactions for catalase, glucose, sucrose and nitrate reduction. Antimicrobial susceptibility tests were performed by the disk diffusion method. In many instances the organisms were resistant to the antimicrobial regimens received by the patients. This was most frequent for nafcillin, gentamicin, kanamycin, clindamycin, and chloramphenicol. On the other hand, the organisms were highly susceptible to penicillin, ampicillin, cephalothin and carbenicillin.
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PMID:Isolation of Corynebacterium xerosis from clinical specimens: infection and colonization. 87 4

Branhamella catarrhalis was formerly regarded as a common, essentially harmless inhabitant of the pharynx. This misapprehension was caused, in part, by confusion with another pharyngeal resident, Neisseria cinerea. The two organisms can now be differentiated by the positive reactions of B. catarrhalis in tests for nitrate reduction and hydrolysis of tributyrin and DNase. B. catarrhalis is currently recognized as the third most frequent cause of acute otitis media and acute sinusitis in young children. It often causes acute exacerbations of chronic bronchopulmonary disease in older or immunocompromised adults and is incriminated occasionally in meningitis, endocarditis, bacteremia, conjunctivitis, keratitis, and urogenital infections. Virulence-associated factors, such as pili, capsules, outer membrane vesicles, iron acquisition proteins, histamine-synthesizing ability, resistance to the bactericidal action of normal human serum, and binding to the C1q complement component, have been identified in some strains. beta-Lactamase producing strains, first detected in 1976, have risen to approximately 75% worldwide. Thus far, however, practically all American strains of B. catarrhalis remain susceptible to alternative antibiotics. A possible selective advantage of recent isolates is their reportedly heightened tendency for adherence to oropharyngeal cells from patients with chronic bronchopulmonary disease.
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PMID:Branhamella catarrhalis: an organism gaining respect as a pathogen. 212 28

Bacteremia due to multiply-antibiotic-resistant Serratia marcescens occurred within 1 week in four patients who were in adjacent beds in an intensive care unit. The strains were serotyped as O14:H12 and were nitrate negative. This unusual biochemical marker was useful in the investigation of the outbreak.
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PMID:Nosocomial outbreak of nitrate-negative Serratia marcescens infections. 704 Apr 69

A new case of Neisseria elongata ssp. nitroreducens bacteremia and endocarditis in a 74-year-old woman who had undergone aortic valve replacement in 1992 is reported in detail. N. elongata ssp. nitroreducens differs from the other subspecies of N. elongata in the additional reduction of nitrate without gas formation. Like most Neisseria spp. except Neisseria meningitidis and Neisseria gonorrhoeae, this N. elongata ssp. nitroreducens is usually classified in the group of "non-pathogenic" Neisseria spp. This case report indicates that the presence of subspecies of this group is significant when isolated from normally sterile sites and can cause severe disease in susceptible individuals.
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PMID:Bioprosthetic valve endocarditis caused by Neisseria elongata subspecies nitroreducens. 881 67

Nitric oxide production was studied in cirrhotic patients with spontaneous bacterial peritonitis (SBP) or with other infections. We followed up on the time course of serum nitrate levels in 51 hospitalized patients aged between 34 and 81 years. Four groups were defined: patients with SBP (group 1, n = 14), patients with bacteremia (group 2, n = 11), patients with urinary tract infection (group 3, n = 11) and patients in a stable clinical condition (group 4, n = 20). The four groups did not differ in terms of Pugh score (11 +/- 1, 10 +/- 1, 11 +/- 1, and 10 +/- 1, respectively). Serum nitrate levels averaged 31 +/- 2 micromol/L in group 4 (84 samples). On the day results of cytobacteriological examination were positive, mean serum nitrate levels were 75 +/- 17, 63 +/- 9, and 36 +/- 9 micromol/L, respectively, in groups 1 (17 cases), 2 (11 cases), and 3 (11 cases) (P < .001). The maximum nitrate values recorded during follow-up were higher in groups 1 (149 +/- 15 micromol/L) and 2 (112 +/- 11 micromol/L) than in group 3 (66 +/- 7 micromol/L; P < .001 and < .01, respectively). These maximum values were recorded in all groups approximately 2 weeks after the infection was diagnosed. The mean duration of NO overproduction, as defined by nitrate level (3)90 micromol/L, was 15 +/- 3 days in group 1 and 5 +/- 1 day in group 2. When the nitrate concentration was studied in serum and ascitic fluid sampled on the same day, it was found to be higher in ascitic fluid than in serum in eight cases of SBP in the period preceding the peak serum nitrate concentration (100 +/- 17 vs. 63 +/- 14 micromol/L; P < .001). Our data indicate that SBP in cirrhotic patients led to a long-lasting increased local production of NO. This overproduction may contribute to maintaining splanchnic vasodilation and thus worsen the hyperkinetic state in these patients.
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PMID:Long-lasting NO overproduction in cirrhotic patients with spontaneous bacterial peritonitis. 918 47

The antibody response to bacteria of the so-called HACEK group, i.e. Haemophilus spp., Actinobacillus actinomycetemcomitans, Cardiobacterium hominis, Eikenella corrodens and Kingella kingae, was measured in sera of six patients with endocarditis. The corresponding isolates from their blood cultures were identified by conventional methods, including reactions for nitrate reduction and catalase as well as acid production from sugars. Crude antigens were prepared by glycine extraction and sonification of the blood culture isolates, and used to determine titers by complement fixation. A patient with Haemophilus parainfluenzae bacteremia received a short course of antibiotic therapy, and relapsed with spondylitis and endocarditis 5 months later. Titers of sera against his own isolate rose from 1:40 to 1:320 and fell to 1:40 after therapy within one year. A patient with C. hominis endocarditis had a similarly prolonged course. The complement fixation titer against his own isolate was already 1:240 before antibiotics were administered. Another patient with C. hominis endocarditis presented a titer of 1:320 2 weeks after the diagnosis. These three patients revealed C-reactive protein values over 50 mg/l in the first serum sample. Decrease of both antibody titers and C-reactive protein values correlated with clinical improvement. Two patients with prosthetic valve replacement 5 months earlier developed C. hominis and K. kingae endocarditis, respectively. At admission, C-reactive protein values were 64 and 82, respectively, and therapy was instituted immediately. The first sera were received 3 and 6 weeks, respectively, after isolation of the corresponding blood culture isolates and revealed already low titers, i. e. 1:80 and 1:60, respectively. A woman with A. actinomycetemcomitans endocarditis received immediate therapy and did not develop titers against her own isolate. CRP was 100 at admission and remained over 50 5 weeks later. We conclude that the complement fixation assay with individual antigen preparations was easy to perform and allowed monitoring of the antibody response in 5 of 6 HACEK endocarditis cases under therapy, but the usefulness of this method to find culture-negative HACEK endocarditis needs to be established.
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PMID:Antibody response in six HACEK endocarditis cases under therapy. 967 92

Overproduction of nitric oxide (NO) upon expression of inducible NO synthase (iNOS) may be responsible for refractory hypotension in septic shock. Whereas high levels of NOS activity have been documented in experimental models of endotoxemia or intravenous challenge with Escherichia coil, much less is known concerning tissue models of Gram-negative infection. We examined NO production (measured as the accumulation of plasma NO3- + NO2-) in a murine model of Gram-negative peritonitis. Plasma NO3- + NO2- increased progressively from 25 microM to peak levels of 50-150 microM 24 h after intraperitoneal challenge with E. coli 0111:B4, similar to values reported for septic shock patients. Treatment of infected mice with NG-monomethyl-L-arginine, an inhibitor of NOS activity, resulted in the efficient inhibition of NO3- + NO2- production. In order to evaluate the roles of interferon-gamma (IFN-gamma) and tumor necrosis factor (TNF-alpha) in the induction of NO synthesis in murine peritonitis, mice deficient in the respective cytokine receptors were studied. In control in vitro experiments, macrophages from IFN-gammaR- or TNFR55-deficient mice, while failing to respond to IFN-gamma or TNF-alpha, respectively, produced high levels of NO under appropriate stimulation. When challenged intraperitoneally with E. coli, IFN-gammaR- or TNFR55-deficient mice exhibited similar levels of bacteremia and NO production as their wild-type controls. These data thus suggest that enhanced NO production during focal Gram-negative infection may occur in the absence of signaling through either IFN-gammaR or TNFR55.
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PMID:Nitric oxide production in experimental gram-negative infection: studies with cytokine receptor-deficient mice. 968 89

Our laboratory has previously shown that after immunization with a strain of Salmonella typhimurium, SL3235, made avirulent by a blockage in the pathway of aromatic synthesis, murine splenocytes were profoundly suppressed in their capacity to mount an in vitro antibody plaque-forming cell (PFC) response to sheep erythrocytes. Evidence indicated that suppression was mediated by nitric oxide (NO), since the in vitro addition of NG-monomethyl-L-arginine blocked suppression. The present studies examined the effect of blocking NO production on Salmonella-induced immunosuppression by in vivo administration of aminoguanidine hemisulfate (AG). AG was administered to C3HeB/FeJ mice in their drinking water (2.5% solution) for 7 days prior to intraperitoneal inoculation with SL3235. AG treatment inhibited the increase in nitrate and nitrite levels in plasma and nitrite levels in the spleen seen in immunized mice. Importantly, AG treatment completely blocked suppression of the splenic PFC response and markedly attenuated the suppression of the response to concanavalin A in immunized mice, providing further evidence that Salmonella-induced immunosuppression is mediated by NO. AG treatment also alleviated the majority of the splenomegaly associated with SL3235 inoculation, which correlated with a blockage of influx of neutrophils and macrophages into spleens, as assessed by flow cytometry. AG treatment unexpectedly resulted in 90% mortality in mice injected with the highly attenuated vaccine strain of Salmonella, SL3235. Increased mortality in AG-treated mice correlated with inability to clear organisms from the spleen by day 15 postinoculation and with persistent bacteremia, compared with control mice. Collectively, these in vivo results underscore the dual biological consequences of NO production following Salmonella infection, with NO being necessary for host defense, but also having the potentially adverse effect of immunosuppression. A unifying hypothesis to explain how these seemingly paradoxical effects could both result from NO production is presented.
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PMID:In vivo blockage of nitric oxide with aminoguanidine inhibits immunosuppression induced by an attenuated strain of Salmonella typhimurium, potentiates Salmonella infection, and inhibits macrophage and polymorphonuclear leukocyte influx into the spleen. 991 5

We describe the isolation of Photorhabdus (Xenorhabdus) luminescens from four Australian patients: two with multiple skin lesions, one with bacteremia only, and one with disseminated infection. One of the patients had multiple skin lesions following the bite of a spider, while the lesions in the other patient were possibly associated with a spider bite. The source of infection for the remaining two patients is unknown. As a member of the family Enterobacteriaceae, P. luminescens is unusual in that it fails to reduce nitrate and ferments only glucose and mannose. It gives negative reactions for lysine decarboxylase, arginine dihydrolase, and ornithine decarboxylase (Moeller). The species is motile, utilizes citrate, hydrolyzes urea, and usually produces a unique type of annular hemolysis on sheep blood agar plates incubated at 25 degrees C. A weak bioluminescence is the defining characteristic. P. luminescens is an insect pathogen and is symbiotically associated with entomopathogenic nematodes. Its isolation from human clinical specimens has been reported previously from the United States. Restriction fragment length polymorphism-PCR analysis of the 16S rRNA gene demonstrated a high level of similarity among the Australian clinical strains and significant differences between the Australian clinical strains and the U.S. clinical strains. However, numerical analyses of the data suggest that the two groups of clinical strains are more similar to each other than they are to the symbiotic strains found in nematodes. This is the first report of the isolation of P. luminescens from infected humans in Australia and the second report of the isolation of this species from infected humans worldwide.
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PMID:Isolation, identification, and molecular characterization of strains of Photorhabdus luminescens from infected humans in Australia. 1052 68


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