Pacemaker pocket infection by Nocardia carnea. First case description and literature review

Acid-fast gram-positive bacilli are a seldom causal agent of cardiac implantable electronic devices (CIED) infections. A pacemaker pocket infection by Nocardia carnea is presented. The objective of this review is to know the incidence of pacemaker pocket infection by Nocardia and to collect information to contribute to the management of this infection. We describe both our case and those found in the literature. Only three cases were found. Two of the patients were older than 70 years without immunosuppression, presenting erythema at the pacemaker implantation site as main symptom. Bloodstream infection was registered in one of them. Three microorganisms were sensitive to cotrimoxazole. The minimum time of antibiotic therapy was 6 weeks. An incomplete device removal was done in one case, resulting in an unfavorable clinical course. The incidence of pacemaker pocket infection by these microorganisms is low, resolved in most cases with antibiotic treatment and device removal.     

The E2 glycoprotein of classical swine fever virus is a virulence determinant in swine

To identify genetic determinants of classical swine fever virus (CSFV) virulence and host range, chimeras of the highly pathogenic Brescia strain and the attenuated vaccine strain CS were constructed and evaluated for viral virulence in swine. Upon initial screening, only chimeras 138.8v and 337.14v, the only chimeras containing the E2 glycoprotein of CS, were attenuated in swine despite exhibiting unaltered growth characteristics in primary porcine macrophage cell cultures. Additional viral chimeras were constructed to confirm the role of E2 in virulence. Chimeric virus 319.1v, which contained only the CS E2 glycoprotein in the Brescia background, was markedly attenuated in pigs, exhibiting significantly decreased virus replication in tonsils, a transient viremia, limited generalization of infection, and decreased virus shedding. Chimeras encoding all Brescia structural proteins in a CS genetic background remained attenuated, indicating that additional mutations outside the structural region are important for CS vaccine virus attenuation. These results demonstrate that CS E2 alone is sufficient for attenuating Brescia, indicating a significant role for the CSFV E2 glycoprotein in swine virulence.     

贯穿式胰管空肠黏膜缝合在胰十二指肠切除术中的对比研究

目的:比较贯穿式胰管空肠黏膜缝合与传统缝合方式用于胰十二指肠切除术(PD)中的效果,并分析其用于PD术中的价值。方法:收集2010年9月-2015年12月我院行PD的60例病人临床资料,按照吻合方法的不同分为2组:贯穿组和传统组,各30例。贯穿组患者均采用贯穿式胰管空肠黏膜缝合,传统组患者均采取传统缝合的方式。对比两组患者临床一般指标(胰肠吻合时间、术中出血量和术后住院时间)以及围术期并发症(如胰瘘、淋巴漏、胃排空障碍、肺部感染、吻合口出血、腹腔脓肿)等情况,并比较两组再手术率和再入院率。结果:贯穿组胰肠吻合时间、术中出血量和术后住院时间较传统组减少,差异有统计学意义(P0.05)。贯穿组围术期胰瘘发生率为10.00%,显著低于传统组的40.00%,差异有统计学意义(P0.05),贯穿组B级胰瘘发生率显著低于传统组,差异有统计学意义(P0.05)。贯穿组再手术率、再入院率与传统组比较差异无统计学意义(P0.05)。结论:贯穿式胰管空肠黏膜缝有利于PD患者术后恢复,且围术期胰瘘发生率低,不失为一种有效的胰肠吻合方式。     

Arabidopsis thaliana as a model for the study of plant–virus co-evolution

Understanding plant–virus coevolution requires wild systems in which there is no human manipulation of either host or virus. To develop such a system, we analysed virus infection in six wild populations of Arabidopsis thaliana in Central Spain. The incidence of five virus species with different life-styles was monitored during four years, and this was analysed in relation to the demography of the host populations. Total virus incidence reached 70 per cent, which suggests a role of virus infection in the population structure and dynamics of the host, under the assumption of a host fitness cost caused by the infection. Maximum incidence occurred at early growth stages, and co-infection with different viruses was frequent, two factors often resulting in increased virulence. Experimental infections under controlled conditions with two isolates of the most prevalent viruses, cauliflower mosaic virus and cucumber mosaic virus, showed that there is genetic variation for virus accumulation, although this depended on the interaction between host and virus genotypes. Comparison of Q_ST-based genetic differentiations between both host populations with F_ST genetic differentiation based on putatively neutral markers suggests different selection dynamics for resistance against different virus species or genotypes. Together, these results are compatible with a hypothesis of plant–virus coevolution.     

Effects of virus infection on demographic traits of an agamospermous population of Eupatorium chinense (Asteraceae)

There are few studies of the interaction between wild plants and viruses. In this paper, the incidence of a geminivirus (tobacco leaf curl virus, TLCV) infection, and its effects on mortality, growth and reproduction of its host-plant, Eupatorium chinense, are reported. A total of 221 plants of an agamospermous population of E. chinense were chosen and their demographic behaviour followed over 2 years (1991–1992). The proportion of infected plants differed between years, with fewer plants infected in 1991 than in 1992. Under low virus incidence (35.3% in 1991), infection was significantly associated with taller plants (>80 cm). However, when the incidence of infected plants increased by almost two times (69.1%) in 1992, this tendency disappeared and small plants were also infected. Virus infection had significant effects on mortality of agamospermous plants. Almost half of the initial number of marked plants (n=221) died after 1 year of observations. Of those dead plants (n=105), 86 plants (82%) were infected in 1991, indicating that virus infection was an important, but not the sole cause of mortality. In 1992, 116 plants were alive, and of these, 40% were infected in 1991, indicating that some infected plants survived 1 year. Agamospermous plants were classified in three groups according to the extent of virus infection (plants infected in 2 years, infected in 1 year and uninfected plants) to detect the effect of virus infection on growth of plants of E. chinense. Infected plants had significantly lower growth rates than healthy plants. Infected plants also produced significantly fewer seeds than uninfected plants. Virus infection, however, had no significant effect on the probability of reproduction in plants of E. chinense, suggesting that infected plants may reproduce but with a lower seed output. In this study, we showed that virus infection may have a strong effect on demographic traits and, as a consequence, on fitness components of plants of E. chinense. These effects were higher than those sometimes observed in other plant-herbivore or plant-pathogen interactions.     

Infection of less virulent Helicobacter pylori strains in asymptomatic healthy individuals in Thailand as a potential contributing factor to the Asian enigma

In Thailand, gastric cancer incidence is considerably low despite the high prevalence of Helicobacter pylori infection. We investigated the prevalence of H. pylori infection and the genotypes of cagA by using 179 stool specimens obtained from asymptomatic Thai individuals. In this study, the prevalence of H. pylori infection was 43.6%, and the detection rate of cagA-positive strains was 43.5%. In addition, the proportion of the highly virulent East-Asian type of cagA was 7.2%. These results indicate that the low prevalence of cagA-positive H. pylori strain as well as the low prevalence of East-Asian genotype cagA-positive strains may contribute to the low gastric cancer incidence.     

Population-based study of Streptococcus suis infection in humans in Phayao Province in northern Thailand

Background

Streptococcus suis infection in humans has received increasing worldwide recognition.

Methods and Findings

A prospective study of S. suis infection in humans was conducted in Phayao Province in northern Thailand to determine the incidence and the risk behaviors of the disease in this region in 2010. Thirty-one cases were confirmed. The case fatality rate was 16.1%, and the estimated incidence rate was 6.2 per 100,000 in the general population. The peak incidence occurred in May. The median age of the patients was 53 years and 64.5% were men. Consumption of raw pork products was confirmed in 22 cases and the median incubation period (range) was 2 days (0–11) after consumption of raw pork products. Isolates from 31 patients were confirmed as serotype 2 in 23 patients (74.2%) and serotype 14 in eight patients (25.8%). The major sequence types (STs) were ST1 (n = 20) for serotype 2 and ST105 (n = 8) for serotype 14. The epidemiological analysis suggested three possible clusters, which included 17 cases. In the largest possible cluster of 10 cases in Chiang Kham and its neighboring districts in May, the source of infection in four cases was identified as a raw pork dish served at the same restaurant in this district. Microbiological analysis confirmed that three of four cases associated with consumption of raw pork at this restaurant were attributable to an identical strain of serotype 2 with ST1 and pulsotype A2.

Conclusions

Our data suggest a high incidence rate of S. suis infection in the general population in Phayao Province in 2010 and confirm a cluster of three cases in 31 human cases. Food safety control should be strengthened especially for raw pork products in northern Thailand.     

Actualización sobre infección por Clostridium difficile en el paciente mayor

Clostridium difficile infection is the most common cause of health care-associated diarrhoea, and its incidence increases with age. Clinical challenges, risk of resistance to treatment, risk of recurrence, and treatment responses are different in elderly.The aim of this review is to discuss the updated epidemiology, pathophysiology, diagnosis, and therapeutic management of C. difficile infection in elderly with the available data.     

Analysis on the Clinical Features of 507 HDV-Infected Patients

The objective of this study was to analyze the clinical feature of hepatitis delta virus (HDV)-infected patients and to discuss the pathological mechanism of hepatitis D. A total of 507 patients with hepatitis due to the infection of HDV were included. The incidence rates of various hepatitis subtypes, the sequelae, the clinical manifestation, the hepatic function, and the hepatic virus makers for all the 507 patients were analyzed statistically. A cohort of 213 patients with hepatitis B, who were also HDV free, served as the control. HDV infection significantly contributed to the increased incidence rate and mortality of severe hepatitis (SH) and cirrhosis (P < 0.01). HDV was also associated with higher incidence rates of hemorrhage in the gastrointestinal tract, abdominal ascites and hepatic encephalopathy, repetitive augmentation of alanine transaminase, and its enhanced magnitude (P < 0.01 or 0.05). The major liver function changes in patients with SH or chronic serious hepatitis was significant compared to the control (P < 0.01). Within the HDV(+) category, HBeAg(?) expression was significantly higher in the HBV DNA(?) group than the HBV DNA(+) group (P < 0.01). The expression of HDAg(+) HBeAg(?) in acute hepatitis, SH, and cirrhosis was significantly higher than that of HDAg(+) HBeAg(+) (P < 0.01 or P < 0.05). The HDV infection was closely associated with the development and prognosis of chronic serious hepatitis, SH, and cirrhosis. HDV infection could inhibit the HBV DNA replication or the HBcAg expression. The direct cytotoxicity of HDV might be the leading pathological factor in AH. HDV might play a major role in the deterioration and chronicization of HDV-co-infected hepatitis B and was responsible for the increased mortality of HBV/HDV patients.     

The Effect of Infection Control Nurses on the Occurrence of Pseudomonas aeruginosa Healthcare-Acquired Infection and Multidrug-Resistant Strains in Critically-Ill Children

Background

Healthcare-acquired Pseudomonas aeruginosa (P. aeruginosa) infections in the Pediatric Intensive Care Unit (PICU), which have a high incidence, increase treatment costs and mortality, and seriously threaten the safety of critically ill children. It is essential to seek convenient and effective methods to control and prevent healthcare-acquired infections (HAIs). This research was conducted to study the effect of infection control nurses on the occurrence of P. aeruginosa HAIs and multi-drug resistance (MDR) strains in PICU.

Methods

The clinical data was divided into two groups, with the age ranging from 1 month to 14 years. One group of the critically ill patients(N = 3,722) was admitted to PICU from 2007 to 2010, without the management of infection control nurses. The other group of the critically ill patients (N = 3,943) was admitted to PICU from 2011 to 2013, with the management of infection control nurses. Compare the mortality, morbidity and the incidence of acquired P. aeruginosa infections to evaluate the effect of infection control nurses.

Results

After implementation of the post of infection control nurses, the patient''s overall mortality fell from 4.81% to 3.73%. Among the patients with endotracheal intubation more than 48 hours, the incidence of endotracheal intubation-related pneumonia decreased from 44.6% to 34.32%. The mortality of patients with endotracheal intubation decreased from 16.96% to 10.17%, and the morbidity of HAIs with P. aeruginosa decreased from 1.89% to 1.07%. The mutual different rate (MDR) dropped from 67.95% to 44.23%. There were remarkable differences in these rates between the two groups (p<0.05).

Conclusion

Implementing the post of infection control nurses is associated with effectively reducing the HAI rate, especially the incidence and morbidity of P. aeruginosa HAIs, reducing PICU mortality, improving P. aeruginosa drug resistance.     

Differential Patterns of Infection and Disease with P. falciparum and P. vivax in Young Papua New Guinean Children

Background

Where P. vivax and P. falciparum occur in the same population, the peak burden of P. vivax infection and illness is often concentrated in younger age groups. Experiences from malaria therapy patients indicate that immunity is acquired faster to P. vivax than to P. falciparum challenge. There is however little prospective data on the comparative risk of infection and disease from both species in young children living in co-endemic areas.

Methodology/Principal Findings

A cohort of 264 Papua New Guinean children aged 1-3 years (at enrolment) were actively followed-up for Plasmodium infection and febrile illness for 16 months. Infection status was determined by light microscopy and PCR every 8 weeks and at each febrile episode. A generalised estimating equation (GEE) approach was used to analyse both prevalence of infection and incidence of clinical episodes. A more pronounced rise in prevalence of P. falciparum compared to P. vivax infection was evident with increasing age. Although the overall incidence of clinical episodes was comparable (P. falciparum: 2.56, P. vivax 2.46 episodes / child / yr), P. falciparum and P. vivax infectious episodes showed strong but opposing age trends: P. falciparum incidence increased until the age of 30 months with little change thereafter, but incidence of P. vivax decreased significantly with age throughout the entire age range. For P. falciparum, both prevalence and incidence of P. falciparum showed marked seasonality, whereas only P. vivax incidence but not prevalence decreased in the dry season.

Conclusions/Significance

Under high, perennial exposure, children in PNG begin acquiring significant clinical immunity, characterized by an increasing ability to control parasite densities below the pyrogenic threshold to P. vivax, but not to P. falciparum, in the 2^nd and 3^rd year of life. The ability to relapse from long-lasting liver-stages restricts the seasonal variation in prevalence of P. vivax infections.     

The influence of photoperiod on embryonic diapause in the tammar wallaby,macropus eugenii

After inoculation of mycoplasmas via ductus deferens in male dogs with a vas deferens fistula the influence on gonads and general state of health was investigated using clinical, andrological, spermatological, microbiological and histological methods.On day 23 and 29 respectively after inoculation two animals showed local reactions within the fistulated gonads which were identified as orchitis and epididymitis. Clinical abnormalities correlated well with the decrease of sperm motility and significant increase (p < 0,05) of aberrant spermatozoa.The microbiological and histological findings are discussed in the light of the incidence of clinical symptoms and the influence of a mycoplasmal infection.     

Incidence of dermatophytosis in a public hospital of São Bernardo do Campo,São Paulo State,Brazil

The incidence of cases of dermatophytosis in dermatology outpatient departments has increased in recent years. Infection control is essential to prevent transmission, and accurate diagnosis of this type of infection is important to avoid confusion with other dermatological processes caused by non-fungal agents. The objective of this study was to determine the incidence of dermatophytosis and its etiological agents in a public hospital of São Bernardo do Campo, Brazil. From February 2005 to May 2006, 273 samples were collected from 191 patients in a public dermatology outpatient department. The samples were collected according to conventional methods used in clinical mycology and direct examinations and cultures were performed. Of the samples suspected of fungal infection, 19% produced positive cultures, and the largest number of samples was from female patients between 31 and 40 years old. The most commonly infected area was the toenails, and the most common infective agents according to microscopic analysis and biochemical tests were the Candida species, which were responsible for 61.6% of the infections. These data agree with findings reported in the literature indicating a lower prevalence of filamentous fungi, such as Epidermophyton, Trichophyton, and Microsporum, in dermatomycosis.     

Increased Inlet Blood Flow Velocity Predicts Low Wall Shear Stress in the Cephalic Arch of Patients with Brachiocephalic Fistula Access

BackgroundAn autogenous arteriovenous fistula is the optimal vascular access for hemodialysis. In the case of brachiocephalic fistula, cephalic arch stenosis commonly develops leading to access failure. We have hypothesized that a contribution to fistula failure is low wall shear stress resulting from post-fistula creation hemodynamic changes that occur in the cephalic arch.MethodsTwenty-two subjects with advanced renal failure had brachiocephalic fistulae placed. The following procedures were performed at mapping (pre-operative) and at fistula maturation (8–32 weeks post-operative): venogram, Doppler to measure venous blood flow velocity, and whole blood viscosity. Geometric and computational modeling was performed to determine wall shear stress and other geometric parameters. The relationship between hemodynamic parameters and clinical findings was examined using univariate analysis and linear regression.ResultsThe percent low wall shear stress was linearly related to the increase in blood flow velocity (p < 0.01). This relationship was more significant in non-diabetic patients (p < 0.01) than diabetic patients. The change in global measures of arch curvature and asymmetry also evolve with time to maturation (p < 0.05).ConclusionsThe curvature and hemodynamic changes during fistula maturation increase the percentage of low wall shear stress regions within the cephalic arch. Low wall shear stress may contribute to subsequent neointimal hyperplasia and resultant cephalic arch stenosis. If this hypothesis remains tenable with further studies, ways of protecting the arch through control of blood flow velocity may need to be developed.     

Susceptibility and resistance of the rock crab,Cancer irroratus,to natural and experimental bacterial infection

The incidence of naturally occuring bacterial infection in a Connecticut population of rock crab, Cancer irroratus, varied between 10 and 60% of the population. The fluctuation in incidence was correlated significantly with hemocyte concentrations. Twelve percent of the crabs sampled during Jenuary were found to be infected with a previously undescribed Vibrio. The Vibrio was demonstrated as pathogenic over a wide range of temperatures. High mortalities in experimentally infected crabs appear to result from hemocyte clumping and extensive intravascular clotting triggered by an endotoxin. The lobster pathogen, Aerococcus viridans var. homari, was found to be pathogenic at 25°C to C. irroratus, a prey species of the lobster. Results suggest that this species can act as a reservior host for A. viridans var. homari.     

Influence of aFusarium culmorum inoculation of wheat onin sacco dry matter degradation of wheat straw and wheat chaff

The aim of this study was to investigate the effect of aFusarium culmorum inoculation of wheat on thein sacco dry matter degradation (DG) of wheat straw and wheat chaff in dairy cows. The ruminal disappearance of dry matter was measured with thein situ nylon bag technique. Samples of wheat straw and wheat chaff from non-inoculated andFusarium-inoculated wheat were used to examine the ruminal dry matter degradability. Samples were subjected to ruminal incubation in two dairy cous fitted with a permanent rumen fistula and incubated for 4, 8, 16, 24, 48, 72, 96 and 120 h. To describe the degradation kinetics, the equation by Ørskov and McDonald (1979) was used. DG rates obtained for contaminates straw and chaff were higher compared to the corresponding rates of the non-contaminated samples, which is assumed to be due to the activity of fungal enzymes. It can be concluded that an infection of wheat withF. culmorum may have an influence on the dry matter degradation of straw and chaff.     

Incidence of cleft palate fistula: an institutional experience with two-stage palatal repair.

The purpose of this study was to determine the incidence of cleft palatal fistula in a series of nonsyndromic children treated at the authors' institution. This retrospective analysis of 103 patients with cleft palate treated by five surgeons between 1982 and 1995 includes 60 boys and 33 girls, whose median age was 18.4 months at the time of surgery. The median length of follow-up was 4.9 years after primary palatoplasty. Cleft palatal fistula was defined as a failure of healing or a breakdown in the primary surgical repair of the palate. Intentionally unrepaired fistulas of the primary and secondary palate were excluded. Extent of clefting was described according to the Veau classification. Statistical examination of multiple variables was performed using contingency table analysis, multivariate logistic regression, and the Wilcoxon rank sum test. The incidence of cleft palatal fistula in this series was 8.7 percent. All of these fistulas were clinically significant. The rate of fistula recurrence was 33 percent. The incidence of cleft palatal fistula when compared by Veau classification was statistically significant, with nine fistulas occurring in patients with Veau 3 and 4 clefts and no fistulas occurring in patients with Veau 1 and 2 clefts (p = 0.0441). No significant differences between patients with and without fistulas were identified with respect to operating surgeon, patient sex, patient age at palatoplasty, type of palatoplasty, and use of presurgical orthopedics or palatal expansion. All three recurrent fistulas occurred in the anterior palate, two in patients with Veau class 3 clefts and one in a patient with a Veau class 4 cleft. The low rate of clinically significant fistula was attributed to early delayed primary closure, with smaller secondary clefts allowing repair with a minimum of dissection and disruption of vascularity.     

Echinococcosis: An Economic Evaluation of a Veterinary Public Health Intervention in Rural Canada

Echinococcosis is a rare but endemic condition in people in Canada, caused by a zoonotic cestode for which the source of human infection is ingestion of parasite eggs shed by canids. The objectives of this study were to identify risk factors associated with infection and to measure the cost-utility of introducing an echinococcosis prevention program in a rural area. We analyzed human case reports submitted to the Canadian Institutes for Health Information between 2002 and 2011. Over this 10 year period, there were 48 cases associated with E. granulosus/E. canadensis, 16 with E. multilocularis, and 251 cases of echinococcosis for which species was not identified (total 315 cases). Nationally, annual incidence of echinococcosis was 0.14 cases per 100 000 people, which is likely an underestimate due to under-diagnosis and under-reporting. Risk factors for echinococcosis included female gender, age (>65 years), and residing in one of the northern territories (Nunavut, Yukon, or Northwest Territories). The average cost of treating a case of cystic echinococcosis in Canada was $8,842 CAD. Cost-utility analysis revealed that dosing dogs with praziquantel (a cestocide) at six week intervals to control cystic echinococcosis is not currently cost-effective at a threshold of $20,000-100,000 per Quality Adjusted Life Year (QALY) gained, even in a health region with the highest incidence rate in Canada ($666,978 -755,051 per QALY gained). However, threshold analysis demonstrated that the program may become cost-saving at an echinococcosis incidence of 13-85 cases per 100,000 people and therefore, even one additional CE case in a community of 9000 people could result in the monetary benefits of the program outweighing costs.