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Bacteriology of sore throats in a Sudanese population.

One hundred and eighty-six throat swabs were collected from patients with sore throats and 164 throat swabs were collected from healthy controls. All swabs were investigated bacteriologically, and sensitivity tests were performed on all pathogenic isolates. Group A Streptococcus pyogenes was the predominant pathogenic organism (24.7%) and Proteus vulgaris the least predominant organism (0.5%) isolated from patients with sore throats. Streptococcus pyogenes infection was found to be most common among school children between the ages of 9 and 12 (61.5%). The pathogenic organisms were found to be sensitive to erythromycin (92.6%).

Adolescent↗

Bacterial eye infection in neonates, a prospective study in a neonatal unit.

One hundred and fifty five neonates with conjunctivitis admitted into the neonatal unit at the Lagos University Teaching Hospital were microbiologically investigated. This was to determine the bacterial aetiologic agent(s) in neonatal eye infection and highlight some risk factors. Antimicrobial susceptibility testing was done on the pathogens isolated using the diskagar diffusion method. The incidence of conjuctivitis in the newborn was 18 per 1000 live births. Predisposing factor noted were vaginal delivery, asphyxia neonatorum and prolonged rupture of membrane. Pathogens predominantly isolated were Staphylococcus aureus (37.4%), Coagilase negative Staphylococci (12.3%), Klebsiella pneumoniae (12.9%) and Pseudomonas aeruginosa (8.2%). Antimicrobial suscepibility results revealed varied degrees of susceptibility to ofloxacin (75%), Cloxacillin, erythromycin, Gentamicin and augumentin (30%) by the gram positive bacteria while most of the gram negative were susceptible to colistin and ofloxacin (above 90%). The high incidence of bacterial eye infection should be minimized by the elimination of the risk factors and adoption of stringent aseptic measures in the care of the neonate.

Conjunctivitis, Bacterial↗

[A clinical evaluation of injectable fluconazole in the treatment of deep mycosis associated with hematological malignancy].

The clinical efficacy and the safety of fluconazole as given at an intravenous dose of 100-400 mg daily were assessed in 7 patients with deep mycosis associated with hematological malignancy. Enrolled in the study were 1 patient with acute lymphatic leukemia, 1 with acute myelocytic leukemia, 2 with acute myelomonocytic leukemia, 2 with malignant lymphoma and 1 with myelodysplastic syndrome. Pathogens isolated from 4 patients were all Candida species including 2 Candida albicans, 1 Candida parapsilosis and 1 Candida krusei. Diagnoses of fungal infections of the patients were Candida pneumonia in 3 patients, candidemia in 1 and fungemia suggested in 3. Assessment of the clinical efficacy was made on 4 patients from whom pathogens were isolated. The global clinical improvement was good in 2 patients and fair in 1 with Candida pneumonia and good in 1 with candidemia. In the mycological assessment, pathogenic fungi were eradicated in 3 patients and decreased in 1 patient. No significant adverse reactions nor abnormality in clinical laboratory tests related with the dosing of fluconazole were observed in any of the patients.

Acute Disease↗

Carriage of enteric bacterial pathogens by house flies in Yangon, Myanmar.

The carriage of enteric bacterial pathogens by house flies, caught from different places of human habitation and at different seasons, was quantitatively determined in the town of Tamwe, Yangon, Myanmar. A total of 186 fly-pools, each containing 10 live flies, were caught in entomological cages by random sampling regarding season, month, frequency and place of collection. A 10% suspension of each homogenised fly-pool in sterile normal saline was prepared on the day of collection and was cultured to isolate pathogens using standard microbiological methods. Escherichia coli, Vibrio cholerae non-O1, and species of Salmonella and Shigella were isolated from 76.3%, 45.7%, 11.8% and 4.8% respectively from all the fly-pools. Enteric bacterial pathogens were isolated more frequently in flies from refuse dumps and animal pens and least commonly in flies from kitchens. Of the E. coli isolates, one pool each from flies trapped in animal pens (n = 30 fly-pools), latrines (n = 32) and refuse dumps (n = 34) produced enterotoxins (ETEC). These ETEC isolates were obtained in the months of June and July. The rates of isolation of pathogens were highest in the hot-wet season. The faecal coliform counts in the fly-pools also increased in this season compared with those in cool-dry and hot-dry seasons. These data suggest that flies may be an important carrier of enteric infections in Myanmar.

Animals↗

Prospective study of diarrhoeal outbreaks in child long-daycare centres in western Sydney.

OBJECTIVE: To investigate outbreaks of diarrhoeal illness in children attending long-daycare centres (LDCs), to characterise parasitic, bacterial and viral isolates from the children's faeces and to identify individual and LDC risk factors for diarrhoea. DESIGN: Eleven-month prospective case-control study of diarrhoeal outbreaks among children in LDCs. SUBJECTS: 2368 children attending 35 LDCs in the western Sydney area. MAIN OUTCOME MEASURES: Frequency of diarrhoeal outbreaks, rate of attack and spread to family members; pathogens isolated from stools; and individual and LDC risk factors. RESULTS: The overall incidence of diarrhoeal disease was low (0.28 outbreaks per centre per year and 0.056 outbreak-associated cases per child-year). Attack rates during outbreaks varied widely (4%-55%; mean, 15%), as did secondary spread rates to family members (1%-15%; mean, 9%). Pathogens were isolated from 7% of symptomatic children and 7% of controls; no outbreak was shown to be caused by a recognised pathogen. Children with outbreak-associated diarrhoeal illness were more likely to have suffered vomiting, poor appetite, lack of energy, fever and to have taken antibiotics in the previous week than other children. Hygiene practices varied widely among centres. CONCLUSIONS: We found low incidence and morbidity from diarrhoeal illness in Australian urban LDCs. Diarrhoea in children in LDCs may be caused predominantly by non-infectious factors such as diet and antibiotic exposure. Current hygiene measures in LDCs seem adequate to prevent and contain outbreaks of infectious diarrhoea.

Child↗

The influence of clinical use of antibiotics and the sensitivity of strains isolated from postoperative infections--a comparison of nosocomial pathogens with strains isolated from the bacterial flora of patients.

In the present study, we investigated how the recent clinical use of antibiotics have altered the antibiotic susceptibility of strains isolated from postoperative infections, especially Gram-negative rods. For Pseudomonas aeruginosa, serogroup E strains accounted for about 20 per cent of postoperative infections, but were unable to be isolated from either the feces of patients on admission or from the appendix contents of patients with appendicitis. It therefore appeared that serogroup E strains were responsible for the nosocomial infections in our department. The strains of methicillin-resistant Staphylococcus aureus and Pseudomonas aeruginosa serogroup E, which we assumed to be nosocomial pathogens, acquired a high level of resistance to antibiotics soon after third-generation cephems became widely used. On the other hand, the antibiotic susceptibility of Enterobacter cloacae, Citrobacter freundii, and the serogroups of Pseudomonas aeruginosa other than E, which were considered to originate from the bacterial flora of patients, did not vary throughout the several years of the study period.

Bacteria↗

Characterization of pathogenic and non-pathogenic African swine fever virus isolates from Ornithodoros erraticus inhabiting pig premises in Portugal.

Ten African swine fever virus isolates from the soft tick Ornithodoros erraticus collected on three farms in the province of Alentejo in Portugal were characterized by their ability to cause haemadsorption (HAD) of red blood cells to infected pig macrophages, using restriction enzyme site mapping of the virus genomes and by experimental infection of pigs. Six virus isolates induced haemadsorption and four were non-haemadsorbing (non-HAD) in pig macrophage cell cultures. The restriction enzyme site maps of two non-HAD viruses, when compared with a virulent HAD isolate, showed a deletion of 9.6 kbp in the fragment adjacent to the left terminal fragment and of 1.6 kbp in the right terminal fragment and an insertion of 0.2 kbp in the central region. The six HAD viruses isolated were pathogenic and produced typical acute African swine fever in pigs and the four non-HAD isolates were non-pathogenic. Pigs that were infected with non-HAD viruses were fully resistant or had a delay of up to 14 days in the onset of disease, after challenge with pathogenic Portuguese viruses. Non-HAD viruses could be transmitted by contact but with a lower efficiency (42-50 %) compared with HAD viruses (100 %). The clinical differences found between the virus isolates from the ticks could have implications for the long-term persistence of virus in the field because of the cross-protection produced by the non-pathogenic isolates. This may also explain the presence of seropositive pigs in herds in Alentejo where no clinical disease had been reported.

African Swine Fever Virus↗

The immunogenicity and pathogenicity of Pasteurella multocida isolated from poultry in Indonesia.

Of 13 field isolates of Pasteurella from chickens and ducks in Indonesia, 10 were confirmed as P. multocida subspecies multocida, one as P. multocida subspecies gallicida and one as P. multocida subspecies septica. Nine were capsular Type A four were Serotype 1, one was Serotype 4, one was Serotype 11, one was Serotypes 4,12, and the remaining six were untypable. Five isolates were pathogenic for mice and two were pathogenic for chickens. Both a trivalent vaccine which included local field isolates and an imported commercial vaccine, were efficacious in layer chickens against challenge with virulent reference and local field strains. Though not statistically significant, the protection provided by the trivalent vaccine against virulent field isolate challenge was slightly better and could provide an improvement over the currently used imported vaccine although further field trials are required. A bacterin vaccine produced from a Serotype 1 field isolate grown in the allantoic sac of embryonated chicken eggs provided chickens with good cross protection against heterologous serotype challenge.

Animals↗

A noncomparative study of cefprozil at two dose levels in the treatment of acute uncomplicated bacterial sinusitis.

The efficacy and safety of cefprozil at two dose levels were evaluated in 110 patients with acute uncomplicated bacterial sinusitis in an uncontrolled, noncomparative, Phase II trial. Ninety patients received 250 mg of cefprozil (low-dose group) and 20 patients received 500 mg of cefprozil (high-dose group) every 12 hours for ten days. Evaluable patients had symptoms consistent with acute sinusitis, pathogens isolated at pretreatment susceptible to cefprozil, and a radiograph positive for sinusitis within 48 hours before treatment. A satisfactory clinical response was achieved in 34 of 39 evaluable patients (87%) in the low-dose group and in all 16 evaluable patients (100%) in the high-dose group. Pathogens were eradicated in 35 of 39 patients (90%) in the low-dose group and in 15 of 16 patients (94%) in the high-dose group. A total of 140 of 155 pathogens (90%) isolated pretreatment were susceptible to cefprozil. Six patients (7%) in the low-dose group and one patient (5%) in the high-dose group reported at least one adverse clinical event.

Adolescent↗

Disparate cultures of middle ear fluids. Results from children with bilateral otitis media.

Cultures of middle ear fluids (MEFs) are needed to determine both efficacy of antibiotics and vaccines, and microbiologic outcome of otitis media (OM). We reviewed data on 221 children, aged 2 months to 12 years; 122 had acute otitis media (AOM), 99 had asymptomatic MEF. We included only Streptococcus pneumoniae, Haemophilus influenzae, Branhamella catarrhalis, and Staphylococcus aureus as pathogens. Of children with AOM, MEF was sterile or contained nonpathogens in both ears in 51, and one or more pathogens in 71. Of these 71, 40 had the same pathogen or pathogens in both ears; 25 patients had a pathogen in one ear and sterile fluid or only nonpathogens in the other; four patients had a different pathogen in each ear; and two patients had two pathogens in one ear and only one in the other. Of those with asymptomatic MEFs, in 80 the effusion was sterile or contained only nonpathogens in both ears, and in 19 contained one or more pathogens. Of these 19, ten had the same pathogen isolated from both ears; nine had a pathogen in one ear and sterile fluid or only nonpathogens in the other. Thus, in 31 children with AOM and nine with asymptomatic MEFs, results of cultures of MEF were different.

Bacteria↗

Microbial adhesion to ionogenic PHEMA, PU and PP implants.

This study concentrates on adhesion of microorganisms to polymeric biomaterials implanted in the urinary tract. A number of extensively used polymeric biomaterials (i.e., poly(hydroxyethyl-methacrylate) and its copolymers with a series of acrylic monomers--acrylic acid and dimethylaminoethyl methacrylate--polyetherurethane and polypropylene (PP)) was prepared by using suitable polymerization methods. Their surface structures were characterized by wettability and surface free energy measurements, scanning electron microscopy, electron spectroscopy for chemical analysis, and attenuated total reflection Fourier transform infrared spectroscopy techniques. It was found that these surfaces have different surface free energies in the range of 26.9-63.0 erg cm-2 with different charge and charge densities. The adherence of two strains of Escherichia coli (non-pathogen and pathogen) isolated from indigenous flora of trachea and pathogen flora of urethral surfaces, and uropathogenic Candida albicans to the polymeric surfaces was studied in vitro by means of microscopic techniques. The hydrophobicity of cell surfaces was determined by using two methods including adhesion to hydrocarbons and contact angle measurements. The uropathogenic E. coli and C. albicans were found to be relatively hydrophobic with a similar surface free energy, approximately 40 erg cm-2, when compared with normal E. coli strain which has 61 erg cm-2 free energy. The uropathogenic strains were poorly adherent to hydrophilic polymer surfaces while showing excellent adherence on hydrophobic PP surfaces. However, a relatively hydrophilic, nonpathogenic E. coli strain showed the opposite adhesion behaviour to the same surfaces.

Bacterial Adhesion↗

A pulsed-field gel electrophoresis typing scheme for Vibrio parahaemolyticus isolates from fifteen countries.

Vibrio parahaemolyticus is an important foodborne pathogen in Taiwan and many other maritime Asian countries where seafood is frequently consumed. A total of 535 strains of V. parahaemolyticus were recovered mostly (97%) from clinical samples obtained in Taiwan or in 14 other countries. These strains were typed by pulsed-field gel electrophoresis following SfiI digestion and a typing scheme was generated. The 115 different patterns identified were grouped into 13 types with dissimilarity values less than 15, plus 16 miscellaneous patterns not grouped into any of the types. Types I, A, D and J contained the most patterns, with the numbers of patterns being 17, 13, 12, and 11, respectively. However, types I, B, D, A, H and C contained the most strains, with the numbers of strains being 204, 73, 71, 54, 29 and 25, respectively. Type I consisted exclusively of the pandemic O3:K6 strains and genetically closely related strains. This PFGE typing scheme for V. parahaemolyticus could be used for the characterization of pathogenic isolates.

Animals↗

ompU genes in non-toxigenic Vibrio cholerae associated with aquaculture.

AIMS: The study was undertaken with the objective of understanding the virulence-associated genes of the CTX and TCP gene clusters in environmental isolates of Vibrio cholerae, an important human pathogen, isolated from the aquaculture environment. The involvement of the ompU gene in conferring bile resistance in these isolates was also evaluated. METHODS AND RESULTS: The V. cholerae isolates were tested by PCR and fluorescent antibody test for O1 (Ogawa and Inaba) and O139 serotypes. All isolates were found to be non-toxigenic V. cholerae confirmed by their positive PCR reaction for toxR but negative for ctx, zot and tcp gene. The hlyA gene was detected in 85% of the strains and ompU in 77%. The results on the bactericidal effect of bile salts suggest that ompU may play a role in conferring bile resistance in non-O1/non-O139 strains. CONCLUSION: The results of the study indicate that most environmental strains lacked the CTX and TCP gene clusters. However, most isolates had the hlyA gene indicating the potential of these environmental strains to cause mild gastroenteritis. It was also observed that strains lacking ompU showed less tolerance to bile salts. SIGNIFICANCE AND IMPACT OF THE STUDY: Information on virulence factors of V. cholerae associated with aquaculture environment and products would be of value in risk assessment for human health.

Adhesins, Bacterial↗

Methicillin-resistant Staphylococcus aureus infections in vascular surgery: increasing prevalence.

BACKGROUND: Methicillin-resistant Staphylococcus aureus (MRSA) is a virulent organism that causes substantial infection-related morbidity and mortality in hospitalized patients. For example, MRSA infection of prosthetic vascular grafts can be limb- and life-threatening in surgical patients. We investigated the incidence of MRSA infection in vascular surgical patients who developed postoperative infectious complications. METHODS: Prospective data (including procedure, nature of complication, and outcome) were collected on all vascular surgery patients (n = 772) over a two-year period from January, 2000, to December, 2001. The study cohort included all patients who developed postoperative complications (n = 119, 15.4%), including infection, unplanned or prolonged intubation, metabolic abnormalities, and myocardial ischemia. Bacteriologic data of all clinical cultures were reviewed and infection-related outcomes were examined. RESULTS: Hospital-acquired infection occurred in 79 (66.4%) of 119 patients who developed postoperative complications. Review of microbiology data (total, 197 bacterial isolates) confirmed that gram-positive organisms were the leading cause of infections, with 120 gram-positive isolates (60.9%). Of the gram-positive isolates, S. aureus was the most common pathogen, isolated in 73 (60.8%) cultures. The single most prevalent organism was MRSA, identified in 42 of 73 (57.5%) of cultures. The site of MRSA infection was confirmed to be the surgical site (54.8%), sputum (17.0%), blood (14.3%), urine (9.5%), peritoneal fluid (2.4%), or catheter insertion site (2.4%). Only four patients had prior MRSA infection or colonization. Prosthetic vascular grafts were placed in 51 (42.9%) of the 119 vascular patients, and 26 patients (51.6%) acquired MRSA infection. Graft removal was required in three patients due to infection (MRSA infection in two patients, Pseudomonas aeruginosa in one patient). Forty percent of patients with MRSA infection required an amputation as their surgical procedure. No patient died of MRSA bacteremia during the study period. Mean hospital length of stay (LOS) was longer in patients with MRSA infection (29.6 d vs. 22.7 days, range 2-174 days, p < 0.05) compared to the total study cohort of vascular patients with postoperative infections. CONCLUSIONS: Methicillin-resistant S. aureus has emerged as the leading cause of postoperative infection in vascular surgery patients, and is associated with substantial morbidity, increased hospital LOS, and higher incidences of amputation and graft removal. Greater emphasis on preoperative screening protocols for MRSA colonization is warranted, in conjunction with aggressive infection control measures, alteration of preoperative prophylactic antimicrobial use in MRSA-colonized patients, and meticulous postoperative surveillance for MRSA infection. Furthermore, antimicrobial treatment of postoperative infectious complications in vascular surgery patients should include empiric coverage for MRSA in institutions where MRSA is endemic.

Adult↗

A multinational, multicentre, non-blinded, randomized study of moxifloxacin oral tablets compared with co-amoxiclav oral tablets in the treatment of acute exacerbation of chronic bronchitis.

The aim of this study was to compare the efficacy and safety of once daily dosing with moxifloxacin (BAY 12-8039) with that of coamoxiclav given three times daily for the treatment of acute exacerbation of chronic bronchitis (AECB). Moxifloxacin (one 400 mg tablet daily) was administered orally for 5 days and co-amoxiclav (three 625 mg tablets daily) was given orally for 7 days. The study was randomized, non-blinded, multinational (12 countries) and multicentre (68 centres). A total of 575 patients, all with clear signs of AECB, were treated, 292 with moxifloxacin and 283 with co-amoxiclav. Of these, 512 patients were evaluable for efficacy (261 in the moxifloxacin group and 251 in the co-amoxiclav group). The primary efficacy parameter was clinical response at 14 days in the evaluable population. A clinical success was classified as resolution or improvement of symptoms. Variables used to assess clinical response included wheeze, cough, dyspnoea, sputum volume, rales and rhonchi. The success rate for moxifloxacin in the evaluable patients was 96.2% and that for co-amoxiclav was 91.6%. The 95% confidence intervals for this difference (0.4%; 8.7%) indicate equivalence in the treatments. Sputum samples were taken from patients and 140 of these contained a pathogen, Haemophilus influenzae being the most frequently isolated. Moraxella catarrhalis and Streptococcus pneumoniae were also commonly isolated pathogens. The eradication rate at 14 days in the evaluable patients was 87.7% in the moxifloxacin group and 89.6% in the coamoxiclav group. Both drugs were well tolerated with no significant differences in the numbers of drug-related adverse events or the numbers of patients withdrawing because of an adverse event. These results and the broad spectrum of antibacterial activity make moxifloxacin a promising and safe alternative to conventional therapy for the empirical treatment of AECB.

Acute Disease↗

Campylobacter enteritis in Johannesburg.

In order to establish a reasonable protocol for a diagnostic laboratory we conducted a survey during which we confined the routine culture of stool samples for Campylobacter fetus to two groups--all infants under 2 years of age, and older children and adults with obviously diarrhoeic stools. Camp. fetus was isolated from 100 of 2323 stool specimens (4,3%). This is within the 3 - 8% isolation rates previously reported from surveys in which all specimens were cultured. Camp. fetus isolates represented 16,9% of all bacterial pathogens isolated, and Black infants showed a significantly greater isolation rate than White infants. We feel that culture for Camp. fetus is an essential part of any routine bacteriological investigation of diarrhoea. A partially selective culture policy for Camp. fetus will result in a recovery rate at least equal to that of Salmonella and enteropathogenic Escherichia coli.

Adult↗

Cell adherence--a determinant of virulence in Yersinia enterocolitica.

The adherence of pathogenic bacteria to eukaryotic cells plays a central role in their ability to colonize the mucosal epithelial surfaces. The adherence by Y. enterocolitica to the mucosal surface of the gut is the initiating event leading to penetration of mucosa. Adhesion of 10 probable pathogenic and one non-pathogenic isolate was studied using ileum and colon epithelial cells of mouse for 90 minutes. Adhesion study revealed that isolates of Y. enterocolitica had a good adhesive property while non pathogenic showed negligible adherence. All isolates showed better adherence to colon epithelial cells. The organism continued to be excreted in faeces up to 8-10 days after oral feeding. Adhesion positive isolates were found to be virulent when tested in mice for diarrhoea and death. Adhesion was found to be thermoregulated.

Animals↗

RANTES, IFN-gamma, CCR1, and CCR5 mRNA expression in peripheral blood, lymph node, and bronchoalveolar lavage mononuclear cells during primary simian immunodeficiency virus infection of macaques.

Primary infection of macaques with pathogenic isolates of simian immunodeficiency virus (SIV) (as a model of HIV infection in humans) represents a unique opportunity to study early lentivirus/host interactions. We sought to determine whether there is a temporal relationship linking SIV replication and dissemination and the expression of the chemokine RANTES (regulated upon activation normal T cell expressed and secreted) and the SIV/HIV coreceptor CCR5 in different tissues during acute SIV infection of macaques. Four cynomolgus macaques were inoculated intravenously with a pathogenic primary isolate of SIVmac251. RT-PCR was used to monitor the expression of RANTES and CCR5 mRNA in fresh isolated mononuclear cells from blood, lymph node, and bronchoalveolar lavages. These expressions were compared to those of IFN-gamma as an indicator of the development of the immune response and to another receptor for RANTES, CCR1, which is not described as a coreceptor for SIV/HIV-1 entry. An enhancement of CCR1/CCR5 mRNA expression was noticed during primary SIVmac251 infection of macaques, mainly in tissue. In the three different compartments investigated, IFN-gamma and RANTES overexpression was noticed by the time of systemic viral replication containment. Our results put CCR5 and RANTES mRNA expression back in the context of inflammatory and immune responses to SIV primary infection.

Animals↗