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PubMed1986

Campylobacter jejuni in hospitalized children with diarrhoea in Chiang Mai, Thailand.

In this hospital based study, Campylobacter jejuni, although endemic in Northern Thailand was not found in a significantly higher percentage of diarrhoea than in control children. It was isolated from the stools of 14 of 208 diarrhoea (6.7%) and 6 of 108 (5.5%) control patients. Ten of the 14 positive diarrhoea cases were mixed infections, other pathogens isolated simultaneously were enteropathogenic E. coli 4x, Shigella spp. 3x, Salmonella spp. 4x, rotavirus 3x, Plesiomonas shigelloides 1x and parasites 3x. Infection with Campylobacter jejuni occurred mainly in the 1-2 year age group and was not found in patients over 5. It was distributed over the year without seasonal peaks. In four of the 14 positive C. jejuni cases no other pathogens were found. One of these suffered 2nd degree malnutrition with measles and one was a chronic diarrhoea case with a history of antibiotic use and past Salmonella and Shigella infections. The remaining two cases had no underlying or associated illnesses. It was concluded that Campylobacter jejuni may be important as an associated pathogen in complicated diarrhoea infections but is rare as a sole causative agent.

Adolescent↗
PubMed1989

Experimental infection of rhesus monkeys with SIV isolated from African green monkeys.

To establish an animal model for AIDS, 6 juvenile rhesus monkeys were infected intravenously with cell-free SIVagmTYO-1, 5, or 7. One animal was infected with SIV of known pathogenicity isolated from a sooty mangabey (SIVsmm). The 2 animals infected with TYO-1, 1 of 2 infected with TYO-7 and the 1 infected with SIVsmm seroconverted within 4-8 weeks after infection and infectious virus could be recovered 8-10 or 44 weeks after infection. Three of the 4 seroconverted monkeys developed a persistent lymphadenopathy 12 weeks after infection. Rhesus monkeys infected with SIVagm could serve as a model to study HIV infection and for vaccine trials.

Acquired Immunodeficiency Syndrome↗
PubMed1988

A double-blind, multicenter, comparative study of the safety and efficacy of cefixime versus amoxicillin in the treatment of acute urinary tract infections in adult patients.

In this 31-site multicenter trial, 565 adult patients with urinary tract infections were randomly assigned to receive either a 10-day course of cefixime 400 mg once daily (n = 279) or amoxicillin 250 mg three times daily (n = 286). Although all patients were included in the safety analysis, only 93 (33 percent) cefixime-treated and 99 (35 percent) amoxicillin-treated patients were fully evaluable for the efficacy analysis. One week after therapy, the evaluable patients treated with cefixime demonstrated a 90 percent clinical cure rate and a 92 percent eradication rate of the baseline pathogen. This compared with an 83 percent clinical cure rate and an 84 percent bacterial eradication rate in the amoxicillin-treated group. The most frequently isolated pathogen was Escherichia coli (80 percent) followed by Proteus mirabilis (10 percent). One hundred thirty-seven (49 percent) of the 279 cefixime-treated and 126 (44 percent) of the 286 amoxicillin-treated patients reported at least one adverse experience during the study. Adverse reactions associated with cefixime were similar to those reported for other beta-lactam antibiotics. The most frequent adverse experiences reported by cefixime-treated patients were diarrhea (15 percent) and stool changes (12 percent). Headaches (11 percent) and diarrhea (9 percent) were the most frequently reported adverse reactions by the amoxicillin-treated patients. Eleven cefixime-treated patients (3.9 percent) and 10 amoxicillin-treated patients (3.5 percent) discontinued therapy because of adverse experiences. Results of this study demonstrate that a once-daily regimen of cefixime is as safe and effective as a three-times-daily regimen of amoxicillin in the treatment of acute urinary tract infections. Although the incidence of bowel changes was somewhat higher in the cefixime treatment group, these events usually resolved when therapy was discontinued.

Acute Disease↗
PubMed2003

Ventilator-associated pneumonia at a tertiary-care center in a developing country: incidence, microbiology, and susceptibility patterns of isolated microorganisms.

OBJECTIVE: Ventilator-associated pneumonia (VAP) complicates the course of up to 24% of intubated patients. Data from the Middle East are scarce. The objective of this study was to evaluate the incidence, microbiology, and antimicrobial susceptibility patterns of isolated microorganisms in VAP in a developing country. DESIGN: Prospective observational cohort study. SETTING: The American University of Beirut Medical Center, a tertiary-care center that serves as a major referral center for Lebanon and neighboring countries. PATIENTS: All patients admitted to the intensive care and respiratory care units from March to September 2001, and who had been receiving mechanical ventilation for at least 48 hours, were included in the study. Results of samples submitted for culture were recorded and antimicrobial susceptibility testing of isolated pathogens was performed. RESULTS: Seventy patients were entered into the study. The incidence of VAP was 47%. Gram-negative bacilli accounted for 83% of all isolates. The most commonly identified organism was Acinetobacter anitratus, followed by Pseudomonas aeruginosa. Fifty percent of all gram-negative bacterial isolates were classified as antibiotic resistant. Compared with patients without VAP, patients with VAP remained intubated for a longer period and stayed in the intensive care unit longer. VAP was not associated with an increased mortality rate. CONCLUSION: Compared with other studies, the results from this referral center in Lebanon indicate a higher incidence of VAP and a high prevalence of resistant organisms. These data are relevant because they direct the choice of empiric antibiotic therapy for VAP.

Acinetobacter↗
PubMed2005

Clinical features and aetiology of septic arthritis in northern Israel.

OBJECTIVE: To assess the clinical features and determine the pathogens responsible for septic arthritis in patients admitted to two community hospitals in the Haifa district in northern Israel over a 17-yr period. METHODS: A retrospective study of the hospital records of patients with septic arthritis admitted to Carmel Medical Center and Bnai Zion Medical Center in Haifa between 1987 and 2003. RESULTS: Of 150 cases identified by discharge summary diagnostic codes, only 110 patients met criteria for the case definition of septic arthritis, and these form the basis of this report. Their mean age was 37.2 yr. Of the patients, 10.4% were recent immigrants, most of them from the former Soviet Union and from Ethiopia. Primary joint disease was reported in 21.8% of the cases, osteoarthritis being most prevalent (8.1%). Of the infected joints, 8.1% were prosthetic. Staphylococcus aureus was the most common pathogen isolated, making up 40% of all positive cultures. Streptococcal and Gram-negative bacilli were both identified in 14%. Eight patients had tuberculous arthritis (9%). Another pathogen, unusual in developed countries, was Brucella species, which was identified in 11% of the cases. Two-thirds of the patients underwent surgical joint drainage while the rest were treated solely with antibiotics. CONCLUSIONS: The present study highlights the importance of characterizing the profile of species causing septic arthritis in specific regions, taking into account ethnic, genetic and environmental factors. In our survey population, tuberculous arthritis is a growing problem, mainly due to recent immigration waves, and brucella is an endemic and common pathogen. It is important to keep a high level of suspicion for these latter two bacteria, as they require special and unique care.

Adolescent↗
PubMedDate not supplied

Spike glycoprotein cleavage recognition site analysis of infectious bronchitis virus.

The spike glycoprotein of infectious bronchitis virus (IBV), a coronavirus, is translated as a precursor protein (So), then cleaved into two subunits (S1 and S2) by host cell serine proteases. In this study, we compared the cleavage recognition site of 55 IBV isolates to determine if the cleavage recognition site sequence, which consists of five basic amino acid residues, correlates with host cell range, serotype, geographic origin, and pathogenicity as it does in orthomyxoviruses and paramyxoviruses. The most common cleavage recognition site observed (33 of 55 viruses) was Arg-Arg-Ser-Arg-Arg, representing at least 11 different serotypes. Thus, cleavage recognition site does not appear to correlate with serotype. We also determined that cleavage recognition site sequence does not correlate with pathogenicity because attenuated and pathogenic isolates (different passages of the same virus) contain identical cleavage recognition site sequences. In addition, nephropathogenic strains had the same cleavage recognition site sequence as many nonnephropathogenic isolates. Cleavage recognition site sequence does correlate with viruses in different geographic regions, which may be an important characteristic to examine in epidemiologic studies. An IBV monoclonal antibody neutralization-resistant mutant (NR 18) had an unusual substitution of Ile for Arg at the fourth position, giving the sequence Arg-Arg-Ser-Ile-Arg, which likely prevents cleavage and, thus, destroys the conformationally dependent monoclonal antibody binding epitope. Six residues on the amino-terminal side of the cleavage recognition site are conserved in 31% of the isolates and consist of only one or two basic amino acids. Thus, the number of basic residues around the cleavage recognition site does not appear to correlate with increased cleavability, host cell range, and increased virulence as it does with envelope glycoproteins in orthomyxoviruses and paramyxoviruses.

Amino Acid Sequence↗
PubMed2002

[Initial empirical antimicrobial therapy with piperacillin/tazobactam in intra-abdominal infections due to perforation of the large intestine and rectum and in postoperative complications after resection of the large intestine and rectum].

One of the basic therapeutic procedures in surgical intraabdominal infections is early administration of antimicrobial drugs. The basic requirement for the selection of antimicrobial drugs is a broad-spectum bactericide action with low toxicity. Within the framework of a retrospective non-comparative investigation the action of the betalactam antibiotic piperacillin combined with the betalactamase inhibitor tazobactam was tested which was used in the initial empirical antimicrobial treatment of 33 patients with intraabdominal infectious complications caused by perforation of the large bowel or dehiscence of the anastomosis on the large intestine or rectum. Twenty-eight patients developed diffuse inflammation of the peritoneum (caused by perforation of a diverticulum in 17, by dehiscence of the anastomosis on the large intestine and rectum after resection on account of carcinoma in 7, by a penetrating injury of the large bowel and rectum in 3 and by postirradiation necrosis of the rectum in one female patient). Five patients developed an intraabdominal abscess as a complication of diverticulitis of the large intestine or as a postoperative infectious complication after resection of the large bowel and rectum. All patients were operated (resection of the large bowel according to Hartmann, or stoma above the site of injury or dehiscence of the intestinal anastomosis or drainage of the abscess). After surgery administration of piperacillin/tazobactam (4.5 g, subsequently after 8 hours). The period of administration was on average 8 days (5 to 11 days). After surgery the contents of the peritoneal cavity were collected for bacteriological examination incl. evaluation of the sensitivity of the isolated bacteria to piperacillin/tazebactam. From the isolated pathogens 58% were Gram-negative aerobic bacteria, in 24% anaerobic bacteria and in 18% enterococci. In 3 patients antimicrobial treatment was because of resistance of isolated bacteria to piperacillin/tazobactam (Klebsiella species, Pseudomonas aeruginosa) combined with aminoglycosides (amikacin, netilmicin). Postoperative complications developed in 9 patients (27%), incl. 3 who died (9%). In patients with intraabdominal infection caused by perforation of the large bowel and rectum or dehiscence of the anastomosis after resection of the large bowel and rectum piperacillin/tazobactam is the antibiotic of choice for the initial empirical antimicrobial treatment on account of its great efficacy against the majority of isolated bacteria, its safety and low toxicity.

Abdominal Abscess↗
PubMed1989

The occurrence of Cryptosporidium oocysts in faecal samples submitted for routine examination at Kenyatta National Hospital.

One hundred and thirty-three loose or diarrhoeic stool specimens from patients admitted at Kenyatta National Hospital were examined for cryptosporidiosis. Oocysts were detected in 5(3.8%) of the total in which Cryptosporidium was the sole pathogenic agent. In addition to Cryptosporidium, other pathogens isolated included bacteria, protozoa and helminths. We therefore report that Cryptosporidium is a cause of diarrhoea and should be looked for in the absence of other pathogenic organisms.

Adolescent↗
PubMed2001

Pathobiology of amber disease, caused by Serratia Spp., in the New Zealand grass grub, Costelytra zealandica.

Amber disease in the New Zealand grass grub (Costelytra zealandica) is caused by some strains of Serratia entomophila or Serratia proteamaculans (Enterobacteriaceae). When treated with pathogenic isolates, larvae ceased feeding within 48 h, developed an amber coloration after 72 h, and entered a long chronic phase without feeding. An acute dose of 2-4 x 10(4) pathogenic bacteria was sufficient to produce disease in 50% of treated larvae. Time to death was directly related to temperature. At 15 degrees C, infected larvae remained in a chronic, nonfeeding state for more than 4 months prior to death. Nonpathogenic isolates, lacking the disease-causing plasmid (pADAP), had no effect on either feeding or disease. Twenty-four hours after ingestion, bacteria were found predominantly in the hindgut and growth occurred primarily within the fermentation chamber and in the head section of the larvae. Nonpathogenic strains did not multiply in treated larvae. Treatment of diseased larvae with antibiotic eliminated Serratia cells from the insects but did not result in restoration of feeding or the dark gut characteristic of the healthy larva.

Animals↗
PubMed1985

Role of imipenem/cilastatin in the treatment of soft tissue infections.

Imipenem/cilastatin was given to 243 evaluable patients with moderately severe to severe soft tissue infections. Cultures prior to therapy yielded Staphylococcus aureus (108 isolates), group D and non-group D enterococci (49), group A streptococci (42), other aerobic gram-positive cocci (72), Pseudomonas aeruginosa (54), Escherichia coli (32), Proteus mirabilis (31), Enterobacter (21), Klebsiella (20), other aerobic gram-negative rods (58), Bacteroides fragilis group (16), and other anaerobes (65). Overall, 95 percent (230 of 243) of the patients treated had clinical cure (137 of 243) or improvement (93 of 243). Of the 506 strains of etiologic bacterial pathogens isolated from these patients and tested against imipenem, 498 (98 percent) were susceptible to the antibiotic. Many were resistant to both older and newer penicillins and cephalosporins. Serial cultures of infection sites revealed that 426 of 498 (86 percent) of pre-therapy bacterial isolates were eradicated by imipenem/cilastatin therapy. Eight of 498 etiologic pathogens (1.6 percent) acquired resistance to imipenem (seven P. aeruginosa and one enterococcus). Such resistance acquisition was associated with clinical failure in two patients. Imipenem/cilastatin appears to be a highly effective, relatively safe therapy of soft tissue infections caused by a wide variety of gram-positive and gram-negative aerobes and anaerobes, both polymicrobial and monomicrobial in nature. Imipenem/cilastatin should be considered particularly when infection by the more antibiotic-resistant of these bacteria is suspected or proved.

Abscess↗
PubMed1999

A triply cloned strain of xylella fastidiosa multiplies and induces symptoms of citrus variegated chlorosis in sweet orange

Xylella fastidiosa isolate 8.1.b obtained from a sweet orange tree affected by citrus variegated chlorosis in the state of Sao Paulo, Brazil, and shown in 1993 to be the causal agent of the disease, was cloned by repeated culture in liquid and on solid PW medium, yielding triply cloned strain 9a5c. The eighth and the 16th passages of strain 9a5c were mechanically inoculated into sweet orange plants. Presence of X. fastidiosa in sweet orange leaves of shoots having grown after inoculation (first-flush shoots) was detected by DAS-ELISA and PCR. Thirty-eight days after inoculation, 70% of the 20 inoculated plants tested positive, and all plants gave strong positive reactions 90 days after inoculation. Symptoms first appeared after 3 months and were conspicuous after 5 months. X. fastidiosa was reisolated from sweet orange leaves, 44 days after inoculation. These results indicate that X. fastidiosa strain 9a5c, derived from pathogenic isolate 8.1.b by triply cloning, is also pathogenic. Strain 9a5c is now used for the X. fastidiosa genome sequencing project undertaken on a large scale in Brazil.http://link. springer-ny.com/link/service/journals/00284/bibs/39n2p106.html

Journal Article↗
PubMed1997

News & notes: adhesiveness of Bacteroides fragilis strains isolated from feces of healthy donors, abscesses, and blood.

Bacteroides fragilis strains attached to oral epithelial cells (ECs) and the cell line Intestine 407 and associated with human phagocytes with different efficiencies depending on their source. The 58%, 75%, and 40% of strains isolated from feces, abscesses, and blood respectively adhered to ECs with good efficiency (11-40 bacteria/cell). Of the strains from feces and abscesses, 17% and 20% exhibited a high adherence (>40 bacteria/cell); however, none of the blood isolates presented this property. Similar results were obtained with the cell line Intestine 407 and human phagocytes. Of the isolates from feces, abscesses, and blood, 20%, 56%, and 71% respectively also exhibited hemagglutination ability, indicating that this property is a virulence trait more frequently present among pathogenic isolates than in commensal strains.

Abscess↗
PubMed1993

Pediatric infective endocarditis in the modern era.

Sixty-two cases of endocarditis occurring in children between January 1977 and February 1992 were reviewed and compared with series from the 1970s and early 1980s. Changes in risk factors, pathogens, diagnostic modalities, and outcome were determined. Complex congenital heart disease (22 cases) and unrepaired ventricular septal defect (9 cases) were the most common underlying lesions. A total of 19 children with normal anatomy had endocarditis; 6 had community-acquired infection and 13 had hospital-acquired endocarditis (11 of these 13 children had central venous catheters in place, including 7 premature infants). Echocardiograms revealed vegetations in 25 of 49 patients; 24 of these patients had positive echocardiographic findings on the first study. Echocardiographic findings were most often negative in children with complex cyanotic heart disease. Staphylococcus aureus (39%) was the most common pathogen isolated and was associated with a higher incidence of central nervous system complications (p < 0.0015) and a greater need for surgical intervention (p = 0.01) than were other pathogens. Methicillin-resistant S. aureus (eight cases) and coagulase-negative staphylococci (three cases) emerged as important pathogens but were not associated with increased morbidity or mortality rates. Fungal endocarditis (six cases) had a 67% mortality rate. Overall the mortality rate was 11%. Endocarditis remained undiagnosed in seven seriously ill patients until postmortem examination. This study indicates that, during the past decade, important changes in risk factors, pathogens, and the susceptible population have altered the presentation and management of endocarditis in children.

Adolescent↗
PubMed1996

Cytokine mRNA expression in mononuclear cells from different tissues during acute SIVmac251 infection of macaques.

We used semiquantitative RT-PCR to monitor the expression of mRNA encoding cytokines (IL-1 beta, IL-6, TNF-alpha, and IL-10) and IFN-gamma in fresh isolated peripheral blood mononuclear cells (PBMCs), lymph node mononuclear cells (LNMCs), and mononuclear cells obtained after bronchoalveolar lavages (BALMCs), of four cynomolgus macaques inoculated intravenously with a pathogenic isolate of simian immunodeficiency virus (SIVmac251). To investigate the effects of the viral load on the expression of the cytokines, two monkeys received 30 mg kg-1 day-1 of didanosine (ddI). The two nontreated monkeys became infected and seroconverted, whereas the ddI-treated monkeys were completely protected as demonstrated by all criteria of diagnosis of SIV infection. Concomitant with the peak of viral replication (2 weeks after the experimental inoculation), high levels of IL-6 mRNA were produced in PBMCs, LNMCs, and BALMCs of the two placebotreated infected monkeys. Overexpression of TNF-alpha and IL-10 mRNAs was sometimes observed in LNMCs and BALMCs. A progressive overexpression of IFN-gamma mRNA, starting 2 weeks after experimental inoculation, was observed in BALMCs from infected animals. Concurrently, a marked increase in the CD8+ lymphocyte percentage in the BAL fluids was detected by FACS analysis. Thus, our results emphasize the importance of a comparative study of the expression of cytokines in different tissues. They suggest the interactions of monocyte/macrophage monokine production with viral replication, as well as the role of IFN-gamma in the development of lung cellular immunity to SIV infection.

Acute Disease↗
PubMed2003

Pathogenic colonization of oral flora in frail elderly patients fed by nasogastric tube or percutaneous enterogastric tube.

BACKGROUND: Aspiration of infected oropharyngeal content is the main cause of aspiration pneumonia. This complication, mainly related to gram-negative bacteria, threatens percutaneous enterogastric tube as well as nasogastric tube (NGT) fed patients. The objective of this study was to examine the oral microbiota of tuboenterally fed patients and compare it with that of orally fed counterparts. METHODS: Patients were recruited for this study from six nursing and skilled nursing facilities with an overall number of 845 beds. Enrolled were 215 patients: Group 1 consisted of 78 patients on NGT feeding, Group 2 consisted of 57 patients on percutaneous enterogastric tube feeding, and Group 3 consisted of 80 patients fed orally who were from the same facilities. Cultures were performed by sampling the oropharynx of each subject in order to identify gram-negative bacteria and Staphylococcus aureus. RESULTS: A high prevalence of potentially pathogenic isolations was found in tuboenterally fed patients: 81% in Group 1 and 51% in Group 2, as compared with only 17.5% in Group 3 (p <.0001). Pseudomonas aeruginosa was cultured from 31% of the subjects in Group 1 and 10% of Group 2, but in none of Group 3 (p <.001). Klebsiella and Proteus were isolated mainly from the NGT fed patients (p <.003). No correlation was found between the time duration on tube feeding or the presence of residual dentition and pathogenic microbiota. CONCLUSION: This study shows that tuboenteral feeding in elderly patients is associated with pathogenic colonization of the oropharynx. These findings are related to the risk of aspiration pneumonia and are compelling for the reevaluation of current oral cleansing procedures.

Aged↗
PubMedDate not supplied

Chemoattractant factors (IP-10, MIP-1alpha, IL-16) mRNA expression in mononuclear cells from different tissues during acute SIVmac251 infection of macaques.

We have used semiquantitative RT-PCR to monitor the expression of mRNA encoding chemoattractant factors IP-10, MIP-1alpha, and IL-16 in freshly isolated peripheral blood mononuclear cells (PBMCs), lymph node mononuclear cells (LNMCs), and mononuclear cells obtained after bronchoalveolar lavages (BALMCs) of two cynomolgus macaques inoculated intravenously with a pathogenic isolate of simian immunodeficiency virus, SIVmac251. Concomitant with the peak of systemic viral replication (two weeks after experimental inoculation) and proinflammatory cytokine IL-6 mRNA expression, high levels of MIP-1alpha and IP-10 mRNA were produced in LNMCs and BALMCs. In BALMCs, in which we have reported a marked progressive overexpression of IFN-gamma mRNA coinciding with an increase in the CD8+ lymphocyte percentages, we noticed a progressive overexpression of IL-16 mRNA. Our results suggest the role of chemokines IP-10, MIP-1alpha, and IL-16 in the development of inflammatory and immune responses during the early stages of lentiviral infection.

Animals↗
PubMed1972

In vitro susceptibility testing with tobramycin.

Tobramycin (nebramycin factor 6) is an aminoglycoside antibiotic active in vitro against many gram-negative species and Staphylococcus aureus. The susceptibility of 191 recently isolated pathogenic bacteria to tobramycin was measured by both a routine broth dilution procedure and the FDA standardized disc technique using a 10-mug disc. Twenty-five isolates each of Escherichia, Enterobacter, Klebsiella, indole-negative Proteus, Pseudomonas, Serratia, and S. aureus, and 16 isolates of group D enterococci were tested. The greatest activity was seen with S. aureus and Pseudomonas species; nearly all isolates of both were inhibited by 0.20 mug or less per ml. Tobramycin was slightly less active against Klebsiella and Enterobacter and moderately active against Escherichia and Proteus, with most isolates of these genera being inhibited by 1.56 mug/ml. Neither Serratia nor the enterococci were particularly susceptible. Correlations between zones of inhibition around the 10-mug disc and minimal inhibitory concentrations were determined, and a zone diameter of 16 mm was recommended as the critical point for prediction of susceptibility.

Aminoglycosides↗
PubMed2002

Clostridium novyi causing necrotising fasciitis in an injecting drug user.

Necrotising fasciitis with pronounced local oedema is described in an injecting drug user. Clostridium novyi was an unexpected single pathogen isolated from infected tissue. The patient was among a cluster of cases, all injecting drug users, presenting with toxaemia and soft tissue infection. The causal role and pathogenicity of C novyi is discussed.

Adult↗