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At least 865 records · Page 48Linked to original sources

Hospital-acquired diarrhea in adults: a prospective case-controlled study in Mexico.

OBJECTIVE: To know the incidence, etiology, risk factors, morbidity, and mortality of nosocomial diarrhea in adults. DESIGN: Nested case-control study, matched by service, length of stay, date of admission, and presence of leukopenia and/or the acquired immunodeficiency syndrome (AIDS). Cases were those who developed nosocomial diarrhea. Controls were those who did not develop nosocomial diarrhea during a comparative period nor during the next ten days. Stool samples were processed in search for parasites, yeasts, bacteria, and rotavirus. SETTING: Third-level referral center, in Mexico City, Mexico, for general internal medicine and surgical problems. PATIENTS: Eligible subjects were all new admissions to the hospital from November 1987 to September 1988. Reasons for exclusion were presence of chronic diarrheal disease or melena. There were 115 cases and 111 controls. RESULTS: Overall risk of acquiring nosocomial diarrhea was 5.5%, or 1.8 episodes per 100 patient-weeks. A potential pathogen was found in 59%. Yeasts and Entamoeba histolytica were the most frequently isolated pathogens. Mortality in cases was 18%, as compared with 5% in controls (p less than .01). Multivariate analysis showed enteral feeding, recent enemas, presence of Candida species, use of antacids/H2-blockers, and presence of nasogastric tubes as significant risk factors for nosocomial diarrhea. CONCLUSIONS: Diarrhea is a common complication in hospitalized patients. It occurs more often than previously suspected and is linked with a substantial mortality. The spectrum of etiologic agents is different from that reported in pediatric hospitals. Given that nosocomial diarrhea may constitute, at least, a marker of severity of illness, it should receive more attention in general hospitals.

Adult↗

DNA fingerprinting of Candida rugosa via repetitive sequence-based PCR.

A repetitive sequence-based PCR (rep-PCR) technique was developed to characterize the genotypic relatedness among Candida rugosa isolates. Two repetitive sequences, viz., Care-2 and Com29 from Candida albicans, were used to design primers Ca-21, Ca-22, and Com-21, respectively. When used alone or in combination, these primers generated discriminatory fingerprints by amplifying the adjacent variable regions of the genome. Twenty-three isolates from burn patients, eight from other human sources, and four C. rugosa isolates pathogenic in animals were placed into nine fingerprinting groups. Different primers placed these isolates into identical groups, indicating that rep-PCR is a specific and reproducible technique for molecular characterization of C. rugosa. Moreover, these primers unequivocally discriminated among other important Candida species such as C. albicans, C. glabrata, C. tropicalis, C. krusei, C. parapsilosis, C. kefyr, and C. lusitaniae. These data confirm the conservation of repetitive sequences in Candida species. Because of its ease and sensitivity, rep-PCR offers a relatively rapid and discriminatory method for molecular typing of C. rugosa in outbreaks.

Animals↗

Aetiology of clinical mastitis in six Somerset dairy herds.

Clinical mastitis was monitored in six Somerset dairy herds for one year. The herds all had three-month geometric mean bulk milk somatic cell counts of less than 250,000 cells/ml. Escherichia coli was the predominant pathogen isolated on all the farms and in all months of the year. Environmental pathogens accounted for 61.4 per cent of all cases of clinical mastitis and for 79.3 per cent of the mastitis cases in which an aetiological agent was identified. The mean annual incidence was 41.6 cases per 100 cows (range 14 to 75). Affected cows suffered a mean of 1.5 cases and 16.4 per cent of quarters suffered at least one repeat case. Mastitis due to E. coli was more severe than mastitis due to other causes and it tended to be more severe in early lactation and during the housing period. Mastitis was significantly more severe (grades 2 and 3) in the herd with the lowest bulk milk somatic cell count and in the herd which was kept indoors throughout the year than in the other four herds. Mastitis was fatal in 2.2 per cent of cases and resulted in the death of 0.6 per cent of the lactating cows.

Animals↗

[New quinolones in urological diseases of an inflammatory nature].

New drugs of the group of the 3rd generation fluoroquinolones i. e. norfloxacin, ciprofloxacin, ofloxacin and pefloxacin possess a high antibacterial activity against the majority of the problem causative agents of urinary infections. This was confirmed by the studies on sensitivity of 950 clinical strains of the pathogens isolated from inpatients of an urological department. Sensitivity of the majority of the pathogens to the fluoroquinolones was the following: 80.3 to 100 per cent among enteric bacteria, 80.2 to 89.6 per cent among Pseudomonas spp. and 94.7 to 100 per cent among Staphylococci, 288 patients were treated with the fluoroquinolones. The patients were divided into 3 groups according to the urinary infection i. e. acute inflammatory diseases, chronic pyelonephritis and chronic inflammatory diseases of the genital tract. The results of the studies estimated by complex clinico-laboratory indices revealed a close efficacy of the drugs in the patients. This was due to their analogous antibacterial spectra and similar pharmacokinetic characteristics investigated in 23 patients after the drug administration by various routes: intravenous and oral. No differences in tolerance of the fluoroquinolones were observed.

Acute Disease↗

[Isolation of anaerobic bacteria from clinical specimens and the drug susceptibility of Bacteroides fragilis].

In the routine bacteriological examination of 8,423 clinical specimens, 906 strains of anaerobic bacteria were isolated at National Taiwan University Hospital between April 1972 and April 1976. Most of the strains were isolated from sites allied to the abdominal cavity and genito-urinary tract. Bacteroides fragilis was the most commonly isolated pathogen. The minimal inhibitory concentrations of 10 different antimicrobial agents to 74 clinical isolates of B. fragilis were determined by an agar dilution method under anaerobic conditions. The percentages of the strains susceptible to clindamycin, carbenicillin, ampicillin, cephalothin, and tetracycline were 98, 92, 75, 41 and 5%, respectively. Rifampin, metronidazole and chloramphenicol also inhibited all isolates in clinically attainable concentrations. All strains were resistant to the aminoglycoside antibiotics, kanamycin and gentamicin.

Abdomen↗

Acute lower respiratory tract infections in children admitted to Port Moresby General Hospital.

The clinical pattern of acute lower respiratory tract infection (ALRTI) in children admitted to Port Moresby General Hospital (PMGH) was studied. Most patients (60%) were less than twelve months of age. Common symptoms were cough, fever and shortness of breath. Common signs were crepitations, chest recession, elevated temperature and tachypnoea. Concurrent illness was common, with evidence of malnutrition in 62% patients. Most patients were anaemic (haemoglobin less than 10g per dl). Blood cultures isolated pathogens in 13% of patients in which it was done, the most common isolate being Haemophilus influenzae. Chest radiograph showed most patients had multisegmental changes, with the lower lobes commonly involved. Of the 129 patients, discharges accounted for 106 (82%), while 15 (12%) absconded and eight (6%) died. Of those 121 discharged or absconding, 15 (12%) were readmitted within three months of departure. Sixty-six (51%) patients stayed in hospital for four days or less. Of the eight patients who died, six (75%) were malnourished, six (75%) were less than eighteen months of age, seven (87.5%) were sick for one week or less before admission, five (62.5%) had received antibiotics before admission and chest radiograph showed more lung zones affected than in those not dying. Of the eight patients who died, six had white cell counts (WCC) performed and none of these was more than 30,000.

Anti-Bacterial Agents↗

Prevalence of enteropathogens in stools of rural Maasai children under five years of age in the Maasailand region of the Kenyan Rift Valley.

Stool samples were collected during August 1994 from seventy rural Maasai children under the age of five years who were living in the Maasailand region of the Kenyan Rift Valley. Microbiological analysis was carried out on these samples to identify which intestinal pathogens were present among the infant population of the Maasai. Of the samples studied 54% were pathogen positive. The most common pathogen isolated was Giardia lamblia which was detected in 31% of the samples. Other pathogens that were detected include: Entamoeba histolytica (23%), Enteropathogenic Escherichia coli (13%), Strongyloides stercoralis (4%), Blastocystis hominis (3%) and Cryptosporidium sp (3%). Although all samples were screened for Campylobacter and rotavirus, neither pathogen was detected. Water samples were taken from all the water sources in the study area and analysed microbiologically. Results showed that all the sources were contaminated with the faecal E. coli whose populations ranged from 14 CFU/100 ml to greater than 1800 CFU/100ml.

Age Distribution↗

Studies of infectivity and pathogenicity of an isolate of Trypanosoma evansi in Yankasa sheep.

The course of experimental infection and pathogenicity of an isolate of Trypanosoma evansi were investigated using eight infected and six uninfected control Yankasa sheep. The sheep were each infected intravenously via the jugular vein with approximately 2.0 x 10(6) T. evansi parasites. The effects of the parasite on body temperature, packed cell volume (PCV), haemoglobin, erythrocytes, total protein, were monitored three times a week for approximately 9 weeks. Body weights were determined once every week for the duration of the experiment. The results showed that all the infected sheep were positive for the parasite. The prepatent period varied between 3 and 6 days. T. evansi produced parasitaemic waves at an average of 8.3 days interval. Two distinct forms of the disease were produced namely, acute (4-14 days postinfection), and chronic (43-59 days postinfection). Anaemia was a distinct feature of the disease. While the mean rectal temperatures were significantly elevated (P < 0.05), the mean values of the haematological parameters of the infected sheep dropped significantly (P < 0.05) compared to the preinfection levels. Observed clinical signs included pale mucous membrane, epiphora, loss of appetite, emaciation, dullness and rough hair coat together with fluctuating pyrexia which in most cases coincided with rise in parasitaemia. It is suggested that the isolate of T. evansi is pathogenic for Yankasa sheep.

Animals↗

Differences in the API 20E biochemical patterns of clinical and environmental Vibrio parahaemolyticus isolates.

Genetic differences in clinical and environmental strains of Vibrio parahaemolyticus have been widely used as criteria in identifying pathogenic isolates. However, few studies have been carried out to assess the differences in biochemical characteristics of V. parahaemolyticus isolates from human and environmental sources. We compared the biochemical profiles obtained by the characterization of V. parahaemolyticus isolates from human infections and the marine environment using the API 20E system. Environmental and clinical isolates showed significant differences in the gelatin and arabinose tests. Additionally, clinical isolates were correctly identified according to the API 20E profile using 0.85% NaCl diluent, but they presented nonspecific profiles with 2% NaCl diluent. In contrast, use of 2% NaCl diluent facilitated correct identification of the environmental isolates. Clinical isolates showed significant differences in up to five biochemical tests with respect to the API 20E database. The API 20E system is widely used in routine identification of bacteria in clinical laboratories, and this discrepancy in an important number of biochemical tests may lead to misidentification of V. parahaemolyticus infection.

Animals↗

A BIR motif containing gene of African swine fever virus, 4CL, is nonessential for growth in vitro and viral virulence.

An African swine fever virus (ASFV) gene with similarity to viral and cellular inhibitor of apoptosis genes (iap) has been described in the African isolate Malawi Lil-20/1 (ORF 4CL) and a cell-culture-adapted European virus, BA71V (ORF A224L). The similarity of the ASFV gene to genes involved in inhibiting cellular apoptosis suggested the gene may regulate apoptosis in ASFV-infected cells and thus may function in ASFV virulence and/or host range. Sequence analysis of additional African and European pathogenic isolates demonstrates that this gene is highly conserved among both pig and tick ASFV isolates and that its similarity to iap genes is limited to the presence of a single IAP repeat motif (BIR motif) in the ASFV gene. To study gene function, a 4CL gene deletion mutant, delta 4CL, was constructed from the pathogenic Malawi Lil-20/1 isolate. Growth characteristics of delta 4CL in swine macrophage cell cultures were indistinguishable from those of parental virus. Infected macrophage survival time and the induction and magnitude of apoptosis in virus-infected macrophages were comparable for cells infected with either delta 4CL or parental virus. In infected swine, delta 4CL exhibited an unaltered Malawi Lil-20/1 virulence phenotype. These data indicate that, although highly conserved among ASFV isolates, the 4CL gene is nonessential for growth in macrophage cell cultures in vitro and for pig virulence. Additionally, despite its limited similarity to JAP genes, 4CL exhibits no anti-apoptotic function in infected macrophage cell cultures. The high degree of gene conservation among ASFV isolates, together with the apparent lack of function in the swine host, suggests 4CL may be a host range gene involved in aspects of infection in the arthropod host, ticks of the genus Ornithodoros.

African Swine Fever↗

Endocarditis by Lactobacillus rhamnosus due to yogurt ingestion?

A young man who ate large quantities of probiotic yogurt developed endocarditis and septic arthritis caused by Lactobacillus rhamnosus. The pathogenic isolate could not be distinguished from the yogurt microflora using methods routinely used in the clinical microbiology laboratory. Only by using more appropriate methodology, including PCR, the pathogen could be distinguished from the yogurt isolate.

Adult↗

Phenotypic and molecular typing of Vibrio harveyi isolates and their pathogenicity to tiger shrimp larvae.

AIMS: The objective of the present study was to identify the biotype(s) and molecular type(s) of Vibrio harveyi associated with pathogenicity in tiger shrimp (Penaeus monodon) larvae. METHODS AND RESULTS: Five luminescent and four nonluminescent V. harveyi isolates were subjected to phenotyping and random amplified polymorphic DNA (RAPD) fingerprinting, and pathogenicity testing to P. monodon mysis. Four isolates induced 34-41% mortality of P. monodon mysis when challenged at the rate of 10(6) CFU ml(-1) within 60 h. Sucrose-fermenting biotypes of V. harveyi appeared to be associated with pathogenicity to larval shrimp. Higher temperature and salinity appeared to play a role on the onset of vibriosis and mortality in the challenged larval shrimp. Pathogenic isolates of V. harveyi could be demarcated as revealed by their clustering in the dendrogram constructed based on the RAPD fingerprints. CONCLUSIONS: Nonluminescent V. harveyi also appear to be important aetiological agents of vibriosis of shrimp larvae. Sucrose-fermenting biotypes are likely to be pathogenic. High temperature may trigger onset of vibriosis. SIGNIFICANCE AND IMPACT OF THE STUDY: Biotyping of V. harveyi isolates and looking for traits, such as ability to ferment sucrose may be helpful in identifying the pathogenic forms, and such approach requires to be investigated further with larger number of isolates.

Animals↗

Reovirus type 2 isolated from cerebrospinal fluid.

An 8-week-old female infant presented with a history of active varicella complicated by Escherichia coli sepsis, oral thrush, hypoalbuminemia, intermittent fevers, diarrhea and feeding intolerance. Rhesus monkey kidney cells inoculated with cerebrospinal fluid revealed reovirus-like particles by electron microscopy. Virus neutralization and RNA-gel electrophoresis studies identified the isolated pathogen as reovirus serotype 2. This report represents one of only a few to isolate reovirus from the central nervous system in humans.

Combined Modality Therapy↗

Acute bacterial diarrhoea in the emergency room: therapeutic implications of stool culture results.

Empiric treatment with ciprofloxacin and norfloxacin has been recommended recently for patients with acute diarrhoeal disease. In a retrospective 6-month study period the results of stool cultures from 209 patients with acute diarrhoea admitted to the emergency room were analysed. Seventy-eight cultures (37%) were positive for one or more bacteria. Shigella was the most commonly isolated pathogen (68%). Shigella sonnei comprised 72% and Shigella flexneri 19% of all the bacterial isolates. While no antimicrobial resistance to ciprofloxacin was found for both Shigella species, only 36 and 26% of the Shigella isolates were sensitive to ampicillin and trimethoprim-sulfamethoxazole (TMP-SMZ), respectively. These findings point out to the emergence of drug resistance to commonly used antimicrobial drugs. Shigella's high sensitivity to the newer quinolones should make this the treatment of choice for the very sick patient, although physicians should be cautioned to the fact that indiscriminate use of this drug could result in the emergence of resistance similar to that noted with ampicillin and TMP-SMZ.

Acute Disease↗

Comparison of the efficacy and safety of moxifloxacin and trovafloxacin for the treatment of acute, bacterial maxillary sinusitis in adults.

In this multicentre, multinational, comparative, double-blind clinical trial, out-patients with both symptoms and radiographic evidence of acute sinusitis were randomly assigned to receive either a seven-day, once daily (o.d.) oral regimen of moxifloxacin (400 mg) or a 10-day o.d. oral regimen of trovafloxacin (200 mg). Among 452 patients considered valid for clinical efficacy, moxifloxacin treatment was found to be statistically equivalent to trovafloxacin (96.9 per cent vs 92.1 per cent -95 per cent CI = 0.6 per cent; 8.9 per cent) at the seven to 10 days post-therapy assessment. At follow-up, the success rate in the moxifloxacin group was 94.9 per cent and that for the trovafloxacin group was 97.6 per cent (95 per cent CI = -4.9 per cent; 1.3 per cent). The predominant causative organisms were Streptococcus pneumoniae, Haemophilus influenzae and Staphylococcus aureus followed by Enterobacteriaceae and Moraxella catarrhalis. The bacteriological success rate at the post-therapy evaluation was similar in both treatment groups: 94.4 per cent and 90.1 per cent in the moxifloxacin and trovafloxacin groups respectively (95 per cent CI = -3.0 per cent; 11.9 per cent). Only three of the 103 baseline isolated pathogens still persisted in the moxifloxacin group, whereas there were 10 of the 121 isolates that failed to respond in the trovafloxacin treatment group. At least one drug-related event was reported by 16.9 per cent of the moxifloxacin-treated patients and by 22.3 per cent of those who received trovafloxacin. CNS events such as dizziness and vertigo were reported more than five times more often in patients receiving trovafloxacin than in the moxifloxacin group. Trovafloxacin recipients were also more than twice as likely to discontinue treatment due to adverse events than moxifloxacin-treated patients. Overall, moxifloxacin was at least as effective clinically and bacteriologically as trovafloxacin and better tolerated.

Acute Disease↗

Temocillin in the treatment of chest infections.

In our study, 16 patients with acute infection complicating severe respiratory disease were treated with temocillin 2g or 3g daily for 5 to 10 days. In 10 patients, a recognised respiratory pathogen, either Haemophilus influenzae (temocillin-sensitive) or Streptococcus pneumoniae (temocillin-resistant), was isolated from sputum before the start of treatment. 13 patients improved clinically but 5 subsequently relapsed. Two patients failed to respond, and 1 died of respiratory failure. There was no clearcut relationship between the clinical progress and sensitivity of the isolated pathogen to temocillin, and there were no adverse effects associated with the administration of temocillin.

Aged↗

Antigenic and genetic analyses of H5 influenza viruses isolated from ducks in Asia.

The hemagglutinin (HA) of six H5 influenza virus strains isolated from ducks in Japan and China in 1976 to 1996 were analyzed antigenically and genetically. Antigenic analysis using a panel of monoclonal antibodies revealed that the HA of H5 influenza viruses isolated from ducks are antigenically closely related to each other. Phylogenetic analysis indicates that the isolates from ducks in Hokkaido were derived from an ancestor common with the highly pathogenic isolates from chickens and humans in Hong Kong in 1997.

Animals↗

[Resistance patterns of various bacteria isolated from slaughtering and breeding calves].

The development of sensitivity to antibiotic and chemotherapeutic agents of a number of important pathogens isolated from veal and replacement calves showed adverse features. This impression is gained when the results of sensitivity testing of these bacteria during the past twenty years are compared. The findings were provided by the Animal Health Service in the Province of Gelderland.

Animals↗