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Cefpirome versus ceftazidime in the treatment of urinary tract infections.

In an open, randomized multiclinic trial, hospitalized patients with upper or complicated lower urinary tract infections requiring treatment with a parenteral antibiotic were randomized to receive 1 g doses of cefpirome (594 patients) or ceftazidime (303 patients) 12 hourly for at least five days. Cefpirome was considerably more active in vitro than ceftazidime against Gram-positive pathogens isolated from the urine samples. At the early follow-up, 2-15 days after treatment, clinical cure was achieved in 86% and 82% of the patients in the cefpirome and ceftazidime groups respectively. Elimination of the causative pathogen without recurrence or early reinfection was achieved in 87% of the patients in both groups. Drug related adverse events occurred in 8.9% of cefpirome treated patients and in 4.6% of those receiving ceftazidime. No specific type of adverse reaction accounted for this difference. Treatment was discontinued because of adverse events in 2.5% and 1.7% of the patients respectively. Cefpirome was found to be safe and at least as effective as ceftazidime for the treatment of urinary tract infections in hospitalized patients.

Ceftazidime↗

Comparison of seven antibiotic treatments with no treatment for bacteriological efficacy against bovine mastitis pathogens.

Milk culture results were retrospectively reviewed from 9007 cases of subclinical mastitis affecting cows housed in dairy herds located in New York and northern Pennsylvania. Cases included in this analysis had at least one mastitis pathogen isolated from the initial milk sample, were recultured within 1 mo, had permanent cow identification, and had records of whether mastitis was treated with an antibiotic or no treatment at all. Overall bacteriological cure rate for 21 mastitis pathogens was 68% (6097 of 9007). Antibiotic treated cases had a higher cure rate (75%) than did untreated cases (65%). Antibiotic treatments that significantly differed from the untreated cure rate of 65% were amoxicillin (82%), erythromycin (76%), cloxacillin (73%), and pirlimycin (44%). Cure rates for antibiotic treatments with cephapirin, hetacillin, or penicillin did not differ from the untreated cure rate. Agents for which some antibiotics were associated with increased cure rates compared with no treatment were Streptococcus agalactiae, streptococci other than Strep. agalactiae, and coagulase-negative staphylococci. The antibiotic most commonly associated with higher cure rates was amoxicillin. Most of the 21 mastitis agents showed no difference in bacteriologic cure rates between any of the 7 antibiotic treatments and no treatment.

Amoxicillin↗

Epidemiologic and clinical characteristics of acute diarrhea with emphasis on Entamoeba histolytica infections in preschool children in an urban slum of Dhaka, Bangladesh.

The epidemiology, clinical features, nutritional status, and causative agents of diarrhea were studied in 289 Bangladeshi children (147 boys and 142 girls) 2-5 years old. The use of improved diagnostic tests for amebiasis enabled for the first time analysis of the contribution of Entamoeba histolytica to total diarrheal illness in this community setting. The average incidence rate of diarrhea was 1.8/child-year, and the average number of diarrheal days was 3.7 days/child-year over an average observation period of 2.8 years/child. Seventy-five percent of the diarrheal episodes were < or = 2 days in duration. Persistent diarrhea was relatively uncommon (0.2% of the children) and chronic diarrhea was observed in only one episode. Compared with malnourished and/or stunted children, better-nourished children experienced significantly fewer diarrheal episodes. The diarrheal incidence rate for children with blood group A was significantly less that that of the children with blood groups O and AB. The most frequent bacterial enteropathogens isolated from diarrheal stool specimens were enterotoxigenic Escherichia coli (9%) and Aeromonas species (9%), followed by Plesimonas shigelloides (4%) and Shigella flexneri (3.8%). Rotavirus was the most common viral agent isolated from diarrheal stool samples (5%). Giardia lamblia, Cryptosporidium parvum, and E. histolytica were identified in 11%, 8.4%, and 8%, respectively, of the diarrheal stool specimens. Dysentery was observed in 7.7% of all diarrheal episodes. The most common pathogens isolated from dysenteric stool were S. flexneri (11.6%), Aeromonas sp. (10%), E. histolytica (8.7%), Campylobacter jejunii (5.8%), P. shigelloides (4.3%), and A. caviae (4.3%). The overall incidence rate of E. histolytica-associated diarrhea was 0.08/child-year. Visible blood and hemoccult test-detected blood loss was found in 7% and 25%, respectively, of cases of E. histolytica-associated diarrhea. Children who had recovered from a diarrheal episode with E. histolytica, but not E. dispar, had half the chance of developing subsequent E. histolytica-associated diarrhea, consistent with the development of species-specific acquired immunity. In conclusion, the use of modern diagnostic tests demonstrated that E. histolytica contributed to overall morbidity from diarrheal illness. Understanding the etiology, frequency, and consequences of acute diarrhea in children from a developing country should aid in the design of interventions to improve child health.

Age Distribution↗

[Bacteremic episodes in pediatric oncologic patients, especially caused by the Streptococcus viridans group].

BACKGROUND: The management of infectious complications plays a major role in the care for pediatric cancer patients. The majority of infections in the neutropenic patient present as fever of unknown origin without recovering a pathogen from the blood stream. The careful evaluation of bacteremic episodes is essential, since knowledge of the bacterial spectrum expected is crucial for the successful anti-infective treatment. PATIENTS AND METHODS: From 1985 to 1995 all bacteremic episodes in pediatric oncology patients at the University Children's Hospital Freiburg were retrospectively analyzed with respect to the pathogens encountered, the antibiotic susceptibility profile and the underlying conditions. RESULTS: Overall, 113 bacteremic episodes were encountered in pediatric oncology patients, 68 of them in patients with hematological malignancies, and 45 in patients with solid tumors. In both patient groups, gram-positive bacteria were predominant with 72% and 58%, respectively. In patients with hematological malignancies, viridans streptococci were the most frequently isolated pathogens (35%) with a relevant morbidity (29% of patients developed a severe sepsis syndrome and/or ARDS), but were found only in 9% of patients with solid tumors. In 28% of patients with leukemia or lymphoma, gram-negative rods were cultured, in 6% Pseudomonas spec., in 4% Acinetobacter spec., and in 18% enterobacteria. In patients with solid tumors, in 38% gram-negative rods were isolated, 7% Pseudomonas spec., 16% Acinetobacter spec., 16% enterobacteria. In 3 patients, fungemia was observed. The antibiotic susceptibility profile was quite favorable in both, gram-positive and -negative bacteria: none of the gram-positive isolates was resistant to vancomycin, none of the Staphylococcus aureus isolates was resistant to oxacillin. All gram-negative bacteria were fully susceptible to ceftazidime, imipenem and ciprofloxacin. CONCLUSION: Gram-positive bacteria account for 2/3 of all bacteremic episodes in pediatric oncology patients. Streptococcus viridans was the most important pathogen in hematological malignancies accounting for a significant, pathogen-specific morbidity.

Adolescent↗

Acute bacterial cholangitis.

Acute bacterial cholangitis refers to a bacterial infection of the biliary tract. Choledocholithiasis is the most common cause of biliary obstruction, with Escherichia coli, Klebsiella spp, and Enterococcus spp the most frequent biliary pathogens isolated in patients with cholangitis. Clinical presentation varies from mild illness to septic shock. The diagnosis of cholangitis is clinical and is supported by laboratory and radiographic findings. Initial treatment is supportive and includes antibiotics to cover the typical pathogens, but definitive treatment requires biliary drainage. Endoscopic retrograde cholangiopancreatography (ERCP) is the preferred technique to achieve biliary decompression with placement of an internal or nasobiliary stent. In cases in which ERCP is unsuccessful or technically not feasible, percutaneous transhepatic biliary drainage (PTBD) is preferred over surgery, which carries significant morbidity and mortality. In order to prevent post-ERCP cholangitis, prophylactic antibiotics are recommended in patients undergoing ERCP for known or suspected biliary obstruction.

Journal Article↗

Lack of toxicity of Helminthosporium maydis-invaded corn and culture filtrates to chicks and mice.

Six isolates of Helminthosporium maydis, obtained from southern leaf blight-damaged corn, were grown separately on autoclaved corn and fed to chicks and mice to evaluate their toxigenicity. Two-, three-, and four-week-old culture filtrates from three pathogenic isolates grown separately on modified Fries medium were also evaluated for toxigenicity. None of the invaded corn samples or culture filtrates affected the weights of chicks or mice when compared to controls. Postmortem examinations did not reveal significant gross lesions. H. maydis was not toxigenic under our experimental conditions.

Animal Feed↗

[Isolation and identification of Bacillus anthracis in an accidental case].

During June to July 2005, a few farmers in Chengde county of Hebei province were got ill after eating beef of sick cattle. The cattle could be infected with Bacillus anthracis. One beef sample and one soil sample contaminated with cattle blood were collected and used for pathogen isolation and identification in laboratory. Two bacteria strains were isolated from beef and soil sample, respectively, and showed typical morphology of Bacillus anthracis on blood agar and under microscope with Gram stain. The two bacteria strains were also positive to standard positive serum of Bacillus anthracis by slide agglutination test. Biochemical characteristics of the two bacteria were tested using API CHB/E strip and analyzed by API software (version 3.3), result showed that the two isolated bacteria were Bacillus anthracis. Polymerase chain reaction (PCR) was used to further characterize the two isolated bacteria strains. Three pairs of primer were designed and used for PCR, and these primers exactly matched the protective antigen gene, edema factor gene and capsule gene, respectively. By analyzed on agarose gel, PCR products were 423bp, 494bp and 397bp, respectively, and this result showed that the two isolated bacteria contained two plasmids, pX01 and pX02, which encoded anthrax toxin and capsule, respectively. Anthrax toxin and capsule were very important virulent factors for Bacillus anthracis. PCR products were purified and then cloned to T vector, positive clone was chose and sequenced. By BLAST with GenBank, sequence of the three genes of the two bacteria strains had a similarity of 99% with Bacillus anthracis A2012 strain, Ames Ancestor strain and A16R strain. Based on results of colonial morphology, serum test and biochemistry characterization, the two bacteria strains are Bacillus anthracis. They can encode anthrax toxin and capsule, and are virulent to animal and human.

Animals↗

[Economic impact of rationalized antibiotic therapy in a general hospital].

PURPOSE: To evaluate the economic impact and the bacterial resistance rates after 2 years of a rationalized antibiotic prescription program in a 502-bed hospital. CURRENT KNOWLEDGE AND KEY POINTS: Prescribing protocols were established by consensus in 1998 and were reinforced a year later by nominative dispensing of the most costly antibiotics. The impact of the program was assessed in terms of changes in the overall cost of antibiotics and in the pattern of bacterial resistance among pathogens isolated in the institution, during the period prior to the onset of the program (1997) and its realization (1998 and 1999). FUTURE AND PROJECTS: The expenses for antibiotic drugs decreased by 46% in 2 years. Resistance rates among the different pathogens studied have remained stable. No increase of mortality was observed. Our rational policy in antibiotic therapy had a positive economic impact. However, new additional measures should be encouraged to prevent antimicrobial resistance.

Anti-Bacterial Agents↗

Scopulariopsis brevicaulis infection in a patient with acute myeloid leukemia.

Scopulariopsis brevicaulis is a soil fungus normally associated with onychomycosis. It causes subcutaneous infection in immunocompromised patients and is rarely isolated from blood. A case of systemic Scopulariopsis brevicaulis infection was reported in a patient with acute myeloid leukemia. The patient developed persistent fever that did not respond to wide spectrum antibiotics and amphotericin B. Scopulariopsis brevicaulis was the only pathogen isolated from blood cultures. The fever subsided with itraconazole and there was no recurrence of fungal infection with prolonged maintenance of oral itraconazole.

Acute Disease↗

[High prevalence of beta hemolytic streptococci isolated from throat swabs in Buenos Aires].

Beta hemolytic streptococci, particulary group A, are the most frequently isolated pathogens in cases of pharyngoamigdalitis. Other beta hemolytic streptococci also produce this pathology. An increase of positive cultures for group A streptococci was detected during 2004 in relation to previous years. The aim of this study was to determine the isolation rates of beta hemolytic streptococci groups A, C and G during a period of 5 years. Pharyngeal exudates were obtained from children (aged 6 months to 18 years) and adults. Swabs were cultured on Columbia agar plates containing 5% sheep blood. Lancefield grouping was performed using a latex immunoagglutination test. Group A beta hemolytic streptococci were isolated significantly more frequently from pediatric population than from adults. Groups A, C and G beta hemolytic streptococci were isolated significantly more frequently during 2004 than in previous years. Group G beta hemolytic was more prevalent in adult population than in patients less than 18 years of age. Among the isolated beta hemolytic streptococci, in adults and children, 18.9% and 5.8% were non-group A streptococci, respectively. Therefore special attention should be paid not only to group A beta hemolytic streptococci but also to other groups. Throat culture is the most reliable method for detecting the presence of the beta hemolytic streptococci and should also be indicated in adult patients.

Adolescent↗

[Surveillance of antimicrobial resistance of bacteria isolated from bloodstream infections: data of the French National Observatory for Epidemiology of Bacterial Resistance to Antibiotics (ONERBA), 1998-2003].

UNLABELLED: The French national observatory for epidemiology of bacterial resistance to antibiotics (ONERBA) includes numerous networks for the surveillance of bacterial resistance to antibiotics. OBJECTIVE: The aim of this study was to update antimicrobial resistance data of bacterial pathogens isolated from blood cultures. METHOD: Data was collected from several surveillance surveys reviewed by the ONERBA scientific committee during 2003. RESULTS: Gram positive cocci and Gram negative bacilli accounted respectively for 45 and 49% of all bacteria isolated from blood cultures (N=19 882). The frequency of MRSA among S. aureus was 35%. The frequencies of resistance to penicillin, amoxicillin and cefotaxime of S. pneumoniae were 10, 2, and 0.2%, respectively. In 2002, 70% of coagulase negative staphylococci were resistant to methicillin. Only 50 and 60% of E. coli isolates were susceptible to aminopenicillin and a combination amoxicillin-clavulanic acid, respectively. Since 2001, the susceptibility of E. coli isolates to ciprofloxacin has been regularly decreasing. Imipenem and ceftazidime were the most active antimicrobial agents against P. aeruginosa with a susceptibility rates below 90%. CONCLUSION: Data provided by the ONERBA should allow to improve the quality of empiric antimicrobial treatments.

Anti-Bacterial Agents↗

Identification of novel antigens that protect against systemic meningococcal infection.

Systemic infection with Neisseria meningitidis leads to a devastating, septicaemic illness with a high mortality, particularly in children. Currently, there are no vaccines to prevent disease caused by strains of N. meningitidis serogroup B, the commonest isolate in developed countries. Here, we describe the identification of vaccine candidates that protect mice against lethal challenge with this bacterium. A total 11 meningococcal proteins that are necessary for establishing systemic infection were expressed as recombinant antigens and assessed for their ability to protect animals against live bacterial challenge; the lactate permease (LctP) and ExbB, which is required for iron acquisition, elicited protective immunity. Both LctP and ExbB are expressed by a wide range of pathogenic isolates of N. meningitidis. Targeting bacterial factors required for pathogenesis may lead to new vaccines to protect individuals from this important human pathogen.

Bacterial Proteins↗

A novel enzyme conferring streptothricin resistance alters the toxicity of streptothricin D from broad-spectrum to bacteria-specific.

Streptothricins (STs) produced by Streptomyces strains are broad-spectrum antibiotics. All STs consist of a carbamoylated D-gulosamine to which the beta-lysine homopolymer (1 to 7 residues) and the amide form of the unusual amino acid streptolidine (streptolidine lactam) are attached. Although many ST-resistance genes have been identified in bacteria, including clinically isolated pathogens and ST-producing Streptomyces strains, only one resistance mechanism has been identified to date. This mechanism involves the modification of the ST molecule by monoacetylation of the moiety of the beta-lysine(s). In this study, we successfully isolated a novel ST-resistance gene (sttH) from Streptomyces albulus, which is a known ST nonproducer. The in vitro analysis of SttH demonstrated that this enzyme catalyzes the hydrolysis of the amide bond of streptolidine lactam, thereby conferring ST resistance. Interestingly, the selective toxicity of ST-D possessing 3x beta-lysine moiety was altered from broad-spectrum to bacteria-specific by the hydrolysis of streptolidine lactam, although ST-F (1 x beta-lysine) was detoxified by SttH in both prokaryotes and eukaryotes (yeasts). STs have not been clinically developed due to their toxicities; however, in this study, we showed that hydrolyzed ST-D (ST-D-acid) exhibits potent antibacterial activity even when its toxicity against eukaryotic cells is reduced by SttH. This suggests that ST-D-acid is a potential candidate for clinical development or for use as a new lead compound for drug discovery.

Bacterial Proteins↗

An in vitro evaluation of antibiotic combinations for urinary tract infections in patients with diabetes mellitus.

This prospective in-vitro study evaluates the synergistic potential of various antibiotic combinations against resistant pathogens isolated from urinary tract infections (UTIs) in patients with diabetes mellitus. Antibiotic combinations using the microtiter checkerboard method showed that overall, synergy could be seen in 41.86%-67.44% cases amongst the five different antibiotic combinations studied against the four predominant resistant pathogens namely Escherichia coli, Pseudomonas aeruginosa, Staphylococcus aureus and Klebsiella ozaenae. The checkerboard synergy studies showed that 69.23% of the S. aureus strains tested were synergistically inhibited by the combination of ofloxacin + cefotaxime [OF+CF], 83.33% of the E. coli strains and 75% of the K. ozaenae strains were synergistically inhibited by the combination of amikacin + cefotaxime [AK+CF], while 58.33% of the P. aeruginosa strains were synergistically inhibited by the combination of amikacin + piperacillin [AK+PP].

Adolescent↗

Isolation of enterobacteria from diarrhoeic West African dwarf goats.

An investigation was undertaken to determine Enterobacteriaceae from faecal swabs of West African dwarf goats suffering from diarrhoea in the Nsukka area of Anambra State, Nigeria. In one academic year a total of 37 enteric bacteria were successfully recovered aseptically from 35 faecal swabs from caprine species. The predominant enterobacteria pathogens isolated from diarrhoeic goats and their relative percentage frequency of isolation were: 27 Escherichia (73%), 7 Proteus (19%) and 3 Shigella (8%). Of the total isolates 73% were Escherichia coli, 13% were Proteus morgani, 3% Proteus mirabilis, 3% Proteus vulgaris and 8% Shigella sonnei. Further work is required to elucidate the precise aetiologic role of these organisms in the pathogenesis of caprine diarrhoea in West African dwarf goats.

Animals↗

A novel RNA mycovirus in a hypovirulent isolate of the plant pathogen Diaporthe ambigua.

Hypovirulent isolates of the fruit tree fungal pathogen Diaporthe ambigua have previously been shown to harbour a double-stranded (ds)RNA genetic element of about 4 kb. In this study, we established the complete cDNA sequence of this dsRNA, which represents a replicative form of a positive-strand RNA virus that we have named D. ambigua RNA virus (DaRV). The nucleotide sequence of the genome is 4113 bp and has a GC content of 53%. Two large ORFs are present in the same reading frame. They are most probably translated by readthrough of a UAG stop codon in the central part of the genome. The longest possible translation product (p125) has a predicted molecular mass of about 125 kDa. A significant homology can be found to the non-structural proteins of carmoviruses of the positive-strand RNA virus family TOMBUSVIRIDAE: These proteins also include the conserved RNA-dependent RNA polymerase (RDRP) domain. In contrast to the genome organization of these plant viruses, no ORF is present at the 3' end of the DaRV genome that encodes a coat protein. Therefore, it is proposed that DaRV is not encapsidated but that it occurs as RNA-RDRP complexes and/or that it might be associated with cell membranes. Interestingly, six putative transmembrane helices are predicted in the N-terminal part of p56 (translation product of the first ORF, N-terminal part of p125), which might direct and anchor the viral complex to membranes. DaRV is a mycovirus with a unique genome organization and has a distant relationship to the plant virus family TOMBUSVIRIDAE:

Amino Acid Sequence↗

Ampicillin-aminoglycoside combinations as initial treatment for neonatal septicaemia or meningitis. A retrospective evaluation of 12 years' experience.

In a retrospective study covering the years 1975-1986, 341 episodes of invasive infections in 338 newborn infants were evaluated. Of the 365 pathogens isolated from blood and/or cerebrospinal fluid, 91% were sensitive to either ampicillin or aminoglycosides or both. Ampicillin resistance was mainly found in very low and low birthweight infants with late-onset infections, in which aerobic Gram-negative rods were common pathogens. In contrast, aminoglycoside resistance was common in early-onset infections, due to the dominance of group B streptococcal infections. The ampicillin-aminoglycoside combination had been given as initial treatment in 189 cases of septicaemia or meningitis. Treatment failed in 36 infections (20%), although all organisms were sensitive to one or both antibiotics. Treatment failed in 6 of 34 patients with meningitis but the failure was not related to ampicillin or aminoglycoside resistance. In conclusion, both in vitro and clinical results show that the ampicillin-aminoglycoside combination can be used as initial treatment of invasive infections in neonates.

Ampicillin↗

[Traveler's diarrhea. Incidence--pathogens--pathophysiology--clinical aspects--prevention and therapy].

About one-third of travellers will be affected by travellers' diarrhoea. Regions with low risk are Northern Europe, the United States, Australia and New Zealand. Intermediate risk is found in Southern Europe, most islands of the Caribbean, Japan, Israel and Southern Africa and high risk in developing countries. Among the most commonly isolated pathogens are enterotoxigenic E. coli, Salmonella, Shigella, Campylobacter, G. lamblia, E. histolytica and viruses. The individual risk depends on the age and constitution of the traveller, on styles of travel and on previous expositure in developing countries. Travellers' diarrhoea is usually a short self-limited disease for 2-5 days. Nutritional prophylaxis along the principle "boil it, cook it, peel it, or forget it" is useful. Prophylaxis with non-antibiotic drugs is only justified in special cases.

Bacteria↗