Influence of fecal shedding of Salmonella organisms on mortality in hospitalized horses

OBJECTIVES: To predict mortality of horses by use of clinical data from the first day of hospitalization, to determine whether fecal shedding of Salmonella organisms is related to severity of clinical disease, and to determine the impact of fecal shedding of Salmonella organisms on mortality. DESIGN: Prospective study. ANIMALS: 1,446 hospitalized horses. PROCEDURE: Medical information was obtained from horses hospitalized in an intensive care unit or isolation facility during a 4.5-year period. A model was created to predict mortality, using covariates determined on the day of admission. Predicted mortality provided a measure of clinical condition. Predicted mortality was compared between horses that were and were not shedding Salmonella organisms in their feces to determine whether shedding was associated with severity of disease. Predicted and observed mortality between horses were also compared to evaluate the association between fecal shedding of Salmonella organisms and mortality. RESULTS: 92 horses were identified as shedding Salmonella organisms. In a multivariable model, 4 variables (heart rate, respiratory rate, rectal temperature, and clinical management) were associated with mortality. A higher predicted probability of death was observed in horses that shed Salmonella krefeld or more than 1 serotype. Relative risk (RR) of mortality was high for horses shedding S typhimurium (RR, 1.94; 95% confidence interval, 1.04 to 3.59) and multiple serotypes (RR, 4.75; 95% confidence interval, 2.29 to 9.84). When the clinical condition (i.e., prior predicted probability of death) was taken into consideration, fecal shedding of Salmonella organisms was not significantly associated with mortality. CLINICAL IMPLICATIONS: In this horse population, fecal shedding of S krefeld was associated with more severe clinical conditions at the time of admission; however, fecal shedding of Salmonella organisms during hospitalization did not alter predicted mortality.     

Detection of Salmonella enteritidis in eggs by the polymerase chain reaction

A polymerase chain reaction (PCR) for the specific detection of the gene sequence, sefA, encoded by all isolates of Salmonella enteritidis, was developed. The PCR could detect as few as four S enteritidis washed bacterial cells but egg contents inhibited the PCR. Eggs spiked with 50 S enteritidis bacterial cells were homogenised, inoculated into buffered peptone water and grown at 37 degrees C for 16 hours, when the PCR was successful. A positive internal control was developed to differentiate between true and false negative PCR results for the detection of S enteritidis. In a limited trial of the egg handling procedures and the PCR, one of 250 chickens' eggs from retail outlets was found to be contaminated with S enteritidis.     

Molecular analysis of Salmonella enteritidis by pulsed-field gel electrophoresis and ribotyping

A total of 61 isolates of Salmonella enteritidis were analyzed by the techniques of pulsed-field gel electrophoresis (PFGE) and ribotyping. Twenty-three of the isolates were from Zurich, Switzerland, and 38 isolates were from the University Hospital, Kuala Lumpur, Malaysia. Five of the Malaysian isolates were hospital-related outbreak strains and were shown to be indistinguishable by PFGE analysis following digestion with three different restriction endonucleases, XbaI (5'-TCTAGA-3'), SpeI (5'-ACTAGT-3'), and AvrII (5'-CCTAGG-3'). The PFGE pattern of an isolate from a suspected carrier staff nurse was found to be identical to those of the hospital outbreak isolates. These isolates were also indistinguishable by ribotyping with SmaI and SphI. The same single PFGE pattern was also detected in 29 of 32 sporadic isolates of S. enteritidis. Four closely related ribotypes were detected among these 29 isolates. Similarly, outbreak-related strains from Switzerland showed close genetic identity by PFGE and ribotyping. Strains obtained from poultry showed more variations in their PFGE patterns and ribotypes, although the patterns were still closely related. In addition, SphI ribotypes A and D among the Swiss strains correlated with phage types 4 and 8, respectively. No correlation of phage types with PFGE pattern was noted. Both PFGE and ribotyping indicate that the S. enteritidis strains circulating in Malaysia and Switzerland are very similar and may be clonally related. Comparison of the PFGE patterns with the ribotypes for 23 Swiss and 16 Malaysian isolates showed that there was a 69% concordance in the grouping of isolates. We conclude that the close genetic similarity observed between epidemiologically unrelated and outbreak-related isolates of S. enteritidis suggests that both PFGE and ribotyping are of limited value in the epidemiological analysis of these particular isolates, possibly because of the highly clonal nature of pathogenic strains of S. enteritidis.     

Interaction of dexamethasone and Salmonella enteritidis immune lymphokines on Salmonella enteritidis organ invasion and in vitro polymorphonuclear leukocyte function

OBJECTIVE: To evaluate the effects of gemeprost on utero-placental and luteal circulation and on the embryo/fetus in normal first trimester pregnancies. STUDY DESIGN: Sixty-seven women with a normal first trimester pregnancy requesting termination of pregnancy for psychosocial reasons were randomly allocated to pre-operative treatment with vaginal suppositories containing placebo or gemeprost. The women underwent transvaginal color and spectral Doppler ultrasound examination before the application of the suppository, 4 h after the application of the suppository but before the abortion, and on the seventh post-operative day. Blood flow velocities in the uterine and subchorionic arteries, the intrachorionic area and arteries in the wall of the corpus luteum and the embryonic/fetal heart rate were measured. RESULTS: The median value for pulsatility index (PI) in the dominant uterine artery was 2.4 before treatment with gemeprost and 8.5 4 h after treatment (P = 0.0006); the corresponding values for time-averaged maximum velocity (TAMXV) being 27 cm/s and 10 cm/s (P = 0.0006). Four (14%) of 28 embryos/fetuses in the gemeprost group were dead 4 h after treatment with gemeprost and the median heart rate of those still alive was significantly lower than before treatment (130 vs. 163 bpm; P = 0.003). In the placebo group, the results for the uterine arteries and the embryonic/fetal heart rate did not differ significantly between the first and second ultrasound examinations. The median values for PI and TAMXV in the arteries of the corpus luteum wall at the first ultrasound examination were 0.71 and 18 cm/s, respectively, in the placebo group and 0.71 and 20 cm/s, respectively, in the gemeprost group. These values remained almost unchanged at the second and third ultrasound examinations in both groups. CONCLUSION: Gemeprost has profound effects on utero-placental circulation in the first trimester and can induce embryonic/fetal bradycardia and sometimes embryonic/fetal demise. It has no unequivocal effect on luteal circulation.     

Psoas abscess caused by Salmonella enteritidis: presentation of a case

The psoas abscess is an entity of infrequent occurrence in daily clinical practice. Many pathogens have been related with the genesis of this focal infections, but it can be said nowadays that the Staphylococcus aureus is more often involved in them. We present the case of a male aged 26, with a culture of purulent drained material, where Salmonella enteritidis, a microorganism of exceptional presentation in this pathology, was isolde. Moreover, some hypothesis have been proposed about the possible physiopathology and the current state of the diagnostic and therapeutic techniques in these processes is revised.     

Phage restriction and the presence of small plasmids in Salmonella enteritidis

Sequence variation within the variable region of the 16S rRNA at position 440 to 480 allowed the synthesis of specific PCR primers for the identification of groups within the species Photorhabdus luminescens, symbionts of entomopathogenic nematodes of the genus Heterorhabditis. For the second PCR primer the highly conserved region at 755 to 795 was used. The P. luminescens type strain specific primer could not recognize any other P. luminescens strain. The primer TEMPERATUS based on the sequence of strain DSM12190 (isolated from North West European H. megidis strain HSH2) identified all P. luminescens associated with H. megidis from North West Europe and two isolates from closely the related nematode strains from Ireland. The primer TROPICUS based on strain DSM12191 (isolated from the nematode type strain H. indica strain LN2) identified P. luminescens of tropical origin isolated from H. indica. Symbionts of H. bacteriophora could not yet be separated into well described groups with the primers used. A comparison of sequence data resulted in the identification of additional groups. The non-symbiotic P. luminescens isolates are distinct in the variable region. The group HELIOTHIDIS contains 15 P. luminescens associated with H. bacteriophora from North East America. The MARELATUS group contains symbionts of the nematode H. marelatus from the West Coast of the US. The data together with the specific symbiotic association of P. luminescens strains with different nematode species support the division of the taxon P. luminescens into different species.     

Efficacy of a live avirulent Salmonella typhimurium vaccine in preventing colonization and invasion of laying hens by Salmonella typhimurium and Salmonella enteritidis

An avirulent live delta cya delta crp Salmonella typhimurium strain chi 3985 that precludes colonization and invasion of chickens by homologous and heterologous Salmonella serotypes was evaluated for its long-term protection efficacy. Chickens vaccinated orally at 2 and 4 wk of age were assessed for protection against oral challenge with wild-type S. typhimurium and Salmonella enteritidis strains at 3, 6, 9, and 12 mo of age. A comparison of Salmonella isolation from vaccinated and nonvaccinated layers after challenge with S. typhimurium or S. enteritidis showed that delta cya delta crp S. typhimurium chi 3985 induced excellent protection against intestinal, visceral, reproductive tract, and egg colonization, invasion, and/or contamination by Salmonella. The duration of protection lasted for 11 mo after vaccination, at which time the experiment was terminated. S. enteritidis and S. typhimurium were isolated from the yolk, albumen, and shells of eggs laid by nonvaccinated chickens challenged with Salmonella. S. typhimurium caused pathological lesions in nonvaccinated chickens, whereas vaccinated and nonvaccinated chickens challenged with S. enteritidis showed no pathological lesion in the visceral and reproductive organs. Vaccination with chi 3985 prevented transmission of S. typhimurium or S. enteritidis into eggs laid by vaccinated layers with no effect on egg production. To our knowledge, this is the first publication confirming that vaccination with live avirulent Salmonella can induce long-term protection against Salmonella infection in layers.     

Sanitation of biowaste compost by using Salmonella enteritidis as a pathogen indicator and survival of Salmonella in seepage water

The following investigations show the frequency of the occurrence of Salmonella in biowastes. Salmonellae, belonging to the serotypes Salmonella enteritidis, infantis and agona were detected in 50% of the investigated biowaste samples. In order to control the reliability of compositing techniques on eliminating pathogens, Salmonella enteritidis was used as a pathogen indicator, which was brought into a container composting process and investigated on it's decline. Although the input indicator bacteria were eliminated in every case latest until the end of container composting, Salmonella was detected in 36% of the investigated fresh compost samples. Every time when Salmonella was detected in input material, the same serotypes were to be found in seepage water and survived there until the end of intensive rot. In laboratory experiments the maximum survival time of Salmonella enteritidis in seepage water at +5 degrees C was 42 days. Seepage water was found out to be a reservoir for survival of Salmonellae and has to be considered as a permanent source of contamination. In the question of the disposal of seepage water there are disagreements between the instructions of TA Siedlungsabfall and TA Luft.     

Synergism of lactate and succinate as metabolites utilized by Veillonella to inhibit the growth of Salmonella typhimurium and Salmonella enteritidis in vitro

The inhibition of salmonellae growth by a Veillonella bacterium isolated from the cecal contents of adult chickens was examined. The Veillonella isolate was grown on an agar medium supplemented with 175 mumol of lactate or succinate/ml. Either 0, 100, 125, 150, or 175 mumol of succinate/ml was added to the lactate medium; either 0, 100, 125, 150, or 175 mumol of lactate/ml was added to the succinate medium; and the pH of all media was adjusted to 6.0. Agar overlays of Veillonella cultures grown on the media were inoculated with Salmonella typhimurium or S. enteritidis. The largest zones of inhibition of salmonellae growth were produced by Veillonella cultures grown on medium supplemented with 175 mumol/ml of both lactate and succinate. The widths of the zones of inhibition decreased as the concentration of lactate was reduced in the succinate medium and as the concentration of succinate was reduced in the lactate medium. Analyses of lactate broth and succinate broth inoculated with Veillonella indicated that inhibition of salmonellae growth on the agar media was related to the production of volatile fatty acids by Veillonella, the presence of residual succinate in the media, and the final pH of the media.     

Inhibition of Salmonella enteritidis by oleuropein in broth and in a model food system

OBJECTIVE: To compare the pharmacokinetics of methylprednisolone in renal transplant recipients on 2 occasions separated by at least 1 month during chronic immunosuppression. DESIGN: A prospective unblinded trial. PATIENTS: Ten renal transplant recipients (aged 25-62 years) evaluated in a public university-affiliated hospital clinic. INTERVENTIONS: All patients received their chronic oral dose of methylprednisolone as a 10-20-minute intravenous infusion during the 2 study periods. MAIN OUTCOME MEASURES: Serum methylprednisolone concentrations were determined by HPLC and were used to generate the pharmacokinetic parameters of the drug. RESULTS: During study 1, which ranged from 1.2 to 24 months posttransplant, the mean +/- SD methylprednisolone dose was 13.2 +/- 6.4 mg. In study 2 (2.5-38.5 mo posttransplant), the mean dose was 10.6 +/- 3 mg. During both study periods, methylprednisolone concentrations exhibited a monoexponential decline. Considerable variability in methylprednisolone clearance was observed between periods in certain patients. Four of the 10 patients demonstrated a reduction in clearance from study 1 to study 2, which ranged from a 28% to a 53% decrease. Two patients exhibited an increase in clearance of 40% and 49%. The mean +/- SD total body clearance in study 1 was 363 +/- 330 mL/min/kg, whereas the mean volume of distribution was 1.18 +/- 0.53 L/kg. The mean elimination rate constant was 0.29 +/- 0.14 h-1, with a mean serum half-life of 2.87 +/- 1.15 h during the first phase. In study 2, the mean methylprednisolone clearance was 261 +/- 150 mL/min/kg (p > 0.05) and the mean volume of distribution was 0.89 +/- 0.31 L/kg (p > 0.05). The mean serum half-life of methylprednisolone was 2.91 +/- 0.60 h (p > 0.05), with the mean elimination rate constant of 0.25 +/- 0.06 h-1 (p > 0.05). CONCLUSIONS: These data demonstrate that intrapatient variability in methylprednisolone clearance exists among certain renal allograft recipients. As a result of the observed variability, patients who are continued on the same dose of methylprednisolone during the posttransplant period of chronic immunosuppression will be subjected to a changing pattern of exogenous glucocorticoid exposure. The impact of these changing patterns requires further prospective evaluation.     

Phage types and ribotypes of Salmonella enteritidis in southern Italy

Differently from other European countries, Southern Italy was affected by a considerable increase in human infections due to Salmonella enterica subsp. enterica serovar Enteritidis (S. Enteritidis) only after 1990. On the present investigation, two groups of S. Enteritidis strains isolated during the low-incidence period 1980-1984 and the epidemic period 1990-1993, respectively, have been submitted to phage-typing and ribotyping in order to ascertain whether the epidemic increase was determined by the spread of a foreign bacterial clone or not. Among the 150 isolates relative to the aforesaid two periods, 12 different phage types (PTs) were observed. PT4 was the most common phage type among the strains isolated in 1980-1984 (61%) as well as in those of the epidemic period 1990-1993 (72%). PT8 was the second most frequent (33%) phage type in 1980-1984. It was substituted by PT1 (19%) in the 1990-1993 period. Analysis of rDNA patterns obtained after Hinc II digestions and Escherichia coli rRNA hybridizations showed 8 different patterns, A to H. The great majority of the strains studied (140 isolates, 93%) belonged to the ribotype A, showing a similar frequency both in 1980-1984 (36 of 39, 92%) and in 19901993 (104 of 111, 94%). The predominance of PT4 and ribotype A among both preepidemic and epidemic strains is in agreement with the hypothesis that host genetic diversity decline and modern farming practices in the poultry industry have facilitated a widespread dissemination of preexisting endemic strains. This hypothesis urges to plan new strategies in preventing S. Enteritidis infections.     

Reduction of fecal contamination of street-vended beverages in Guatemala by a simple system for water purification and storage, handwashing, and beverage storage

CD4+ cells from young (3 months) and old (19 months) mice were stimulated by plate-bound anti-CD3 monoclonal antibody (mAb) alone or also by soluble anti-CD28 mAb. Supernatants were analysed by enzyme-linked immunosorbent assay (ELISA) to determine cytokine concentrations. Total RNA was extracted from cells, reverse transcribed and the cDNA amplified by polymerase chain reaction (PCR) to evaluate the amount of specific mRNA. The results indicate that anti-CD3 alone is not sufficient to induce interleukin-2 (IL-2) production in CD4+ cells from both young and old mice. However, anti-CD28, together with anti-CD3 mAb, induces a much higher production of IL-2 in CD4+ cells from young as compared with old mice. Conversely, interferon-gamma (IFN-gamma) production is also induced by anti-CD3 alone and is higher in CD4+ cells from old as compared with young mice. Upon addition of anti-CD28 mAb, IFN-gamma production increases in both groups, but it remains much higher in old than in young mice. Also the production of IL-4 and IL-10 is induced by anti-CD3 mAb but it is increased by the addition of anti-CD28 mAb. CD4+ cells from old mice produce more IL-4 and IL-10 as compared with cells from young mice. The amounts of cytokine specific mRNA in CD4+ cells from young and old mice parallel the cytokine levels in culture supernatants. Results on the mRNA turnover indicate that when CD4+ cells are stimulated by anti-CD3 or costimulated also by anti-CD28 mAb, the IFN-gamma, IL-4 and IL-10 specific mRNAs are more stable in old than in young mice, suggesting that mRNA stability has a relevant role in the different patterns of cytokine production.     

Epidemiology and control of egg-associated Salmonella enteritidis in the United States of America

The isolation rate for Salmonella enterica serotype Enteritidis (SE) in humans in the United States of America (USA) increased from 1,207 sporadic isolates identified in 1976 (0.6 isolates/100,000 population) to 10,201 identified in 1995 (4.0/100,000 population). The proportion of reported Salmonella isolates which were SE increased from 5% to 25% during the same time period. In 1990, 1994, and 1995, SE was the most commonly reported reported Salmonella serotype in the USA. Much of this increase has been associated with the consumption of contaminated shell eggs. An examination of the results of a United States Department of Agriculture (USDA) survey of spent hens at slaughter and unpasteurised liquid egg at breaker plants (liquid egg processors) in 1991 and 1995 reveals an increase in the prevalence of SE isolates overall and in most regions of the USA. SE phage type 4 (pt 4), the predominant SE phage type in other parts of the world, has emerged in the egg industry in the western USA concurrent with a sharp increase in the number of sporadic human SE pt 4 isolates in California and Utah. Research on the molecular structure and virulence of SE pt 4 isolates from the USA as compared with isolates from other parts of the world (human and poultry) should be a priority. A comparison of DNA from pt 4 isolates from the USA and Europe may provide information about the potential threat to public health and poultry in the USA from this phage type. Some regional success in the reduction of human illness as a result of SE control efforts is apparent. The Pennsylvania Egg Quality Assurance Program has shown progress in reducing SE infection in participating flocks. At a national level, however, neither the incidence of human illness due to SE nor the prevalence of SE in flocks and unpasteurised liquid eggs have decreased significantly, despite the implementation of the USDA 'trace back' regulation from 1990 to 1995, and intensified efforts to educate food handlers and to enforce safe food handling practices. More effort is needed to control SE at every stage of the egg continuum, from production through to consumption. A risk-reduction approach, with barriers to the introduction and multiplication of the pathogen throughout the farm-to-table continuum, is the most practical method for reducing human illness from SE in shell eggs at present. An effective long-term solution will require interdisciplinary efforts involving government, industry, consumers, and academics. Interventions should be developed and evaluated in compliance with the potential for reducing the risk to human health and cost-effectiveness.     

Effect of induced molting on the severity of intestinal lesions caused by Salmonella enteritidis infection in chickens

A study was conducted to describe the intestinal lesions caused by Salmonella enteritidis infection in 20-, 40-, and 74-week-old white leghorn chickens that were undergoing a feed deprivation-induced molt. The chickens were infected on the fourth day after feed was removed. At 4 days postinfection (8 days of feed deprivation), cecal and cecal tonsil inflammation was significantly greater in molted infected chickens than in unmolted infected chickens. The cecal lamina propria and epithelium of molted infected chickens contained heterophilic infiltrates, and there were heterophils and sloughed epithelial cells in cecal lumina. Colonic inflammation, consisting of heterophils infiltrating lamina propria and epithelium, occurred more often in molted infected chickens than in unmolted infected chickens. Immunoperoxidase staining of intestinal sections from 20- and 40-week-old chickens revealed S. enteritidis antigen in the lamina propria of cecum, cecal tonsil, and occasionally the colon of molted infected chickens. The character of the S. enteritidis-induced intestinal lesions associated with molting was similar for different ages of birds.     

Effect of nisin on heat injury and inactivation of Salmonella enteritidis PT4

To gain more insight into decision making around the termination of resuscitation (CPR), we studied factors which influenced the time before discontinuing resuscitation, and the criteria on which those decisions were based. These criteria were compared with those of the European Resuscitation Council (ERC) and the American Heart Association (AHA). For this study, we reviewed the audiotapes of resuscitation attempts in a hospital. A total of 36 attempts were studied, involving 27 men and nine women, mean (S.D.) age 64 (18) years. A total of 19 patients received resuscitation on general wards, and 17 in the emergency room after an out-of-hospital circulatory arrest. The median interval time (range) from start to termination was 33 min (8-81 min). Results from multiple linear regression showed that a delay greater than 5 min in first advanced life support measures, drawing a sample for biochemical analysis, and the patient's response shown by return of spontaneous circulation were independently associated with the time of terminating resuscitation. The team used a number of criteria which can be found in the guidelines of the ERC and the AHA, but also used additional criteria. The ERC and the AHA criteria were not sufficient to cover all termination decisions. We conclude that the point in time to terminate resuscitation is not always rationally chosen. Updating of the current guidelines for terminating resuscitation and training resuscitation teams to use these guidelines is recommended.     

Genotypic characterization of Salmonella enteritidis phage types by plasmid analysis, ribotyping, and pulsed-field gel electrophoresis

Pulsed-field gel electrophoresis (PFGE) was used to resolve XbaI and SpeI macrorestriction fragments from 60 defined phage type (PT) reference strains of Salmonella enteritidis. The level of discrimination was compared to that afforded by plasmid profile analysis and ribotyping. Twenty-eight distinct XbaI pulsed-field profiles (PFPs) were observed, although a single type, PFP X1, predominated. Absence of the 57-kb spv-associated fragment was observed for three PT reference strains, and the profile was designated PFP X1A. The XbaI macrorestriction profiles of a further four PT reference strains were altered by the presence of plasmid-associated bands. Twenty-six SpeI-generated PFPs (plus one subtype) were observed for the same strains. No SpeI fragment corresponding to the 38-MDa serovar-specific plasmid was detected. The distribution of XbaI and SpeI profiles did not always correspond, producing a total of 32 combined PFPs for the 60 PT reference strains. This compared with a total of 18 different plasmid profiles and three PvuII ribotypes generated by the same strains. The results of this study indicate that PFGE may offer an improved level of discrimination over other genotypic typing methods for the epidemiological typing of S. enteritidis.     

Reduction of bacterial contamination during mechanical autotransfusion by uv irradiation--initial results

Electrodiagnostic techniques used in an EMG-Laboratory and the diagnostic value in focal mononeuropathies are presented. The electrodiagnostic techniques include nerve conduction studies and needle electrode examination. Measurement of distal latency, amplitude, conduction velocity and the finding of focal conduction block may localize the focal character of the mononeuropathy. The needle electrode examination gives further information about distribution, extent, activity, or chronicity of the disease, especially in cases with axonal injuries. Some normal electrodiagnostic patterns are presented, accompanied by some illustrative pathological cases.