Characteristics and prognosis in patients with prosthetic vascular graft infection: a prospective observational cohort study

Prosthetic vascular graft infection (PVGI) is a devastating complication, with a mortality rate of up to 75%, which is especially caused by aortic graft infection. The purpose of this study was to evaluate factors associated with in-hospital mortality of patients with definite graft infection, and with long-term outcome. We reviewed medical records of 85 patients treated for PVGIs defined by positive bacterial culture of intraoperative specimens or blood samples, and/or clinical, biological and radiological signs of infection. In-hospital patient mortality was defined as any death occurring during the initial treatment of the graft infection. Cure was defined as the absence of evidence of relapsing infection during long-term follow-up (≥1 year). Eighty-five patients (54 aortic and 31 limb graft infections) treated by surgical debridement and removal of the infected prosthesis (n=41), surgical debridement without removal of prosthesis (n=34) or antimicrobial treatment without surgery (n=10) were studied. The only microbiological difference observed between patients with early (occurring within 4 months after surgery) vs. late PVGI and between those with aortic vs. limb PVGI was the incidence of PVGI caused by Staphylococcus aureus, which was greater in patients with limb PVGI. Overall cure was observed in 93.2% of 59 patients with a follow-up of a minimum of 1 year. Overall in-hospital mortality was 16.5% (n=14). Two variables were independently associated with mortality: age >70 years (OR 9.1, 95% CI 1.83-45.43, p 0.007) and aortic graft infection (OR 5.6, 95% CI 1.1-28.7, p 0.037).     

Microbiologic epidemiology depending on time to occurrence of prosthetic joint infection: a prospective cohort study

Objectives

The high microbiologic diversity encountered in prosthetic joint infection (PJI) makes the choice of empirical antimicrobial therapies challenging, especially in cases of implant retention or one-stage exchange. Despite the risk of dysbiosis and toxicity, the combination of vancomycin with a broad-spectrum β-lactam is currently recommended in all cases, even if Gram-negative bacilli (GNB) might be less represented in late PJI. In this context, this study aimed to describe the microbiologic epidemiology of PJI according to the chronology of infection.

Respiratory virus infection among hospitalized adult patients with or without clinically apparent respiratory infection: a prospective cohort study

ObjectivesTo determine the viral epidemiology and clinical characteristics of patients with and without clinically apparent respiratory tract infection.MethodsThis prospective cohort study was conducted during the 2018 winter influenza season. Adult patients with fever/respiratory symptoms (fever/RS group) were age- and sex-matched with patients without fever/RS (non-fever/RS group) in a 1:1 ratio. Respiratory viruses were tested using NxTAG? Respiratory Pathogen Panel IVD, a commercially-available multiplex PCR panel.ResultsA total of 214 acutely hospitalized patients were included in the final analysis, consisting of 107 with fever/RS (fever/RS group), and 107 age- and sex-matched patients without fever/RS (non-fever/RS group). Respiratory viruses were detected in 34.1% (73/214) of patients, and co-infection occurred in 7.9% (17/214) of patients. The incidence of respiratory virus was higher in the fever/RS group than in the non-fever/RS group (44.9% (48/107) versus 23.4% (25/107), p 0.001). Influenza B virus, enterovirus/rhinovirus and coronaviruses were detected more frequently in the fever/RS group, whereas parainfluenza virus 4B and adenovirus were detected more frequently in the non-fever/RS group. Among the non-fever/RS group, chest discomfort was more common among patients tested positive for respiratory viruses than those without respiratory virus detected (44% (11/25) versus 22% (18/82), p 0.04).ConclusionsRespiratory viruses can be frequently detected among hospitalized patients without typical features of respiratory tract infection. These patients may be a source of nosocomial outbreaks.     

Continuous high-dose vancomycin combination therapy for methicillin-resistant staphylococcal prosthetic hip infection: a prospective cohort study

Few data are available on treatment and outcome of methicillin-resistant (MR) staphylococcal prosthetic joint infections. Vancomycin remains the treatment of choice for these infections, but its efficacy and safety in bone-and-joint infections are insufficiently documented. We conducted a prospective cohort study on 60 patients treated between November 2002 and December 2008 for chronic MR staphylococcal (44 S. epidermidis, nine other coagulase-negative Staphylococcus and seven S. aureus) prosthetic hip infections (PHIs). Twentytwo patients had previously undergone surgery for their PHI and 21 had previously received antibiotics. All patients had surgery (exchange arthroplasty for 58 patients, resection arthroplasty for two) and received an antibiotic regimen combining high-dose continuous intravenous vancomycin infusion (target serum concentration 30–40 mg/L) with another antibiotic for 6 weeks, followed by an additional 6 weeks of oral intake. Two years after surgery, infection was considered cured in 41 (68%) patients and only two relapses occurred after one-stage exchange arthroplasty. Nineteen (32%) patients experienced nephrotoxicity that was generally mild (RIFLE class R for 14 patients, class I for four patients and class F for one patient) and most often reversible. Continuous high-dose intravenous vancomycin combination therapy is an effective, feasible and reasonably safe treatment of chronic MR staphylococcal PHI.     

Timing of antibiotics in septic patients: a prospective cohort study

ObjectivesTo evaluate the effect of timing and appropriateness of antibiotics administration on mortality in patients diagnosed with sepsis according to the Sepsis-3 definition.MethodsThis prospective cohort study was conducted in patients diagnosed with sepsis according to the Sepsis-3 definition at the emergency department of Korea University Ansan Hospital from January 2016 to January 2019. The time to antibiotics was defined as the time in hours from emergency department arrival to the first antibiotic administration. Cox proportional hazards regression analysis was used to estimate the association between time to antibiotics and 7-, 14- and 28-day mortality.ResultsOf 482 patients enrolled onto this study, 203 (42.1%) of 482 and 312 (64.7%) of 482 were diagnosed with septic shock and high-grade infection respectively. The median time to receipt of antibiotic therapy was 115 minutes. Antibiotics were administered within 3 and 6 hours in 340 (70.4%) of 482 and 450 (93.2%) of 482 patients respectively. Initial appropriate empirical antibiotics were administered in 375 (77.8%) of 482 patients. The time to and appropriateness of the initial antibiotics were not associated with 7-, 14- and 28-day mortality in multivariate analysis. The Sequential Organ Failure Assessment (SOFA) score (adjusted hazard ratio (aHR) 1.229, 95% confidence interval (CI) 1.093–1.381, p 0.001) and initial lactate levels (aHR 1.128, 95% CI 1.034–1.230, p 0.007), Charlson comorbidity index (aHR 1.115, 95% CI 1.027–1.210, p 0.014), 2-hour lactate level (aHR 1.115, 95% CI 1.027–1.210, p 0.009) and SOFA score (aHR 1.077, 95% CI 1.013–1.144, p 0.018) affected 7-, 14- and 28-day mortality respectively. Subgroup analysis with septic shock, bacteraemia and high-grade infection did not affect mortality rates.ConclusionsTime to receipt of antibiotics may not affect the prognosis of patients with sepsis if a rapid and well-trained resuscitation is combined with appropriate antibiotic administration within a reasonable time.     

Chronic graft-versus-host disease: a prospective cohort study.

Chronic graft-versus-host disease (CGVHD) is a major cause of morbidity and mortality following allogeneic bone marrow transplantation (BMT). We studied 159 patients with CGVHD longitudinally to characterize the natural history of CGVHD and identify reliable predictors of response and long-term mortality. Rates of response to treatment were 61%, 53%, and 50% at 6 months, 1 year, and 2 years, respectively. A high incidence of infections (7 of 1,000 patient-days at 0 to 6 months, 2.5 of 1,000 patient-days at 6 months to 1 year, and 0.6 of 1,000 patient-days at 1 to 2 years) was observed. After a median follow-up of 8.4 years, an overall survival rate of 40% was observed. The overall survival rate was 63% (95% confidence interval [CI], 56%-71%) at 1 year, 51% (95% CI, 43%-59%) at 2 years, and 39% (95% CI, 31%-47%) at 10 years. In multivariate analysis, age older than 20 years (RR = 1.5; 95% CI, 0.9%-2.5%; P =.09), progressive onset of CGVHD (RR = 1.6; 95% CI, 1.0%-2.4%; P =.04), platelet count of <100,000/ microL (RR = 2.1; 95% CI, 1.3%-3.4%; P =.001), and GI involvement (RR = 1.5; 95% CI, 1.0%-2.4%; P =.05) were associated with increased mortality. Among patients surviving more than 6 months, no response (RR = 4.5; 95% CI, 1.9%-10.5%; P =.0006) and partial response (RR = 2.5; 95% CI, 1.1%-6.1%; P =.04) to treatment at 6 months also were significant predictors of mortality. The prevalence of active CGVHD was 33% at 2 years. However, the cumulative incidence of successful discontinuation of therapy was only 13% at 2 years. Among patients with clinical resolution of CGVHD, only 18% were off immunosuppressive therapy by 2 years, and 89% by 4 years. Despite high initial response rates, a large majority of patients had active disease requiring prolonged immunosuppression. This requires improved infection prevention for a longer time. Recognition of a high-risk group should facilitate assignment of more intensified regimens. Better treatment regimens need to be identified to improve survival and limit toxicity of prolonged immunosuppression.     

Analysis of incidence of infection with enterotoxigenic Escherichia coli in a prospective cohort study of infant diarrhea in Nicaragua.

Diarrheal episodes with enterotoxigenic Escherichia coli (ETEC) were prospectively monitored during the first 2 years of life in a cohort of 235 infants from Leon, Nicaragua. ETEC was an etiological finding in 38% (310 of 808) of diarrheal episodes and in 19% (277 of 1,472) of samples taken as asymptomatic controls at defined age intervals (P = <0.0001). The majority of diarrheal episodes (80%) occurred before 12 months of age. The major ETEC type was characterized by colonization factor CFA I and elaboration of both heat-labile enterotoxin and heat-stable enterotoxin (ST). The proportion of E. coli strains with CFA I was significantly higher in cases with diarrhea (P = 0.002). The second most prevalent type showed putative colonization factor PCFO166 and production of ST. The prevalence of PCFO166 was approximately 20%, higher than reported before. Children with a first CFA I episode contracted a second ETEC CFA I infection 24% of the time, compared with 46% for ETEC strains of any subtype. Most of the ETEC episodes were of moderate severity, and only 5% (15 of 310) were characterized as severe. In conclusion, our results give valuable information for the planning of intervention studies using ETEC vaccines.     

The impact of carbapenemase-producing Enterobacteriaceae colonization on infection risk after liver transplantation: a prospective observational cohort study

ObjectiveTo investigate the impact of colonization with carbapenemase-producing Enterobacteriaceae (CPE) on the CPE infection risk after liver transplantation (LT).MethodsProspective cohort study of all adult patients undergoing LT at our centre over an 8-year period (2010–2017). Individuals were screened for CPE colonization by rectal swabs at inclusion onto the waiting list, immediately before LT and weekly after LT until hospital discharge. Asymptomatic carriers did not receive decolonization, anti-CPE prophylaxis or pre-emptive antibiotic therapy. Participants were followed up for 1 year after LT.ResultsWe analysed 553 individuals who underwent a first LT, 38 were colonized with CPE at LT and 104 acquired colonization after LT. CPE colonization rates at LT and acquired after LT increased significantly over the study period: incidence rate ratios (IRR) 1.21 (95% CI 1.05–1.39) and 1.17 (95% CI 1.07–1.27), respectively. Overall, 57 patients developed CPE infection within a median of 31 (interquartile range 11–115) days after LT, with an incidence of 3.05 cases per 10 000 LT-recipient-days and a non-significant increase over the study period (IRR 1.11, 95% CI 0.98–1.26). In multivariable analysis, CPE colonization at LT (hazard ratio (HR) 18.50, 95% CI 6.76–50.54) and CPE colonization acquired after LT (HR 16.89, 95% CI 6.95–41.00) were the strongest risk factors for CPE infection, along with combined transplant (HR 2.60, 95% CI 1.20–5.59), higher Model for End-Stage Liver Disease at the time of LT (HR 1.03, 95% CI 1.00–1.07), prolonged mechanical ventilation (HR 2.63, 95% CI 1.48–4.67), re-intervention (HR 2.16, 95% CI 1.21–3.84) and rejection (HR 2.81, 95% CI 1.52–5.21).ConclusionsCPE colonization at LT or acquired after LT were the strongest predictors of CPE infection. Prevention strategies focused on LT candidates and recipients colonized with CPE should be investigated.     

Psychological factors in the aetiology of infertility: a prospective cohort study

The objectives were to identify and measure psychological factorscharacterizing the period following the cessation of contraceptionand to assess these psychological factors as predictors of thecouples' fertility. A cohort of 63 couples with initially undeterminedfertility status was prospectively studied, first shortly afterthe cessation of contraception, then 13 months later. The ChildProject Questionnaire was constructed to assess psychologicalvariations following the cessation of contraception. An InterspouseDifference Score was constructed to measure the difference betweenthe spouses' responses. Three male and three female factorswere derived from the questionnaire. The Interspouse DifferenceScore was significantly greater in infertile than in fertilecouples. Two psychological factor scores were significantlyhigher in fertile subjects: the wives' level of positive expectationsrelated to motherhood, and the husbands' quality of integrationbetween the wish for a child and sexual relationships. Withinthe group of fertile couples, time to pregnancy was predictedby the husbands' above-cited factor and by the wives' frequencyof thoughts and concerns related to the desired child. The resultssupport the conclusion that in both women and men, psychologicalfactors specifically related to the project of conceiving achild are significant predictors of the couple's fertility status.     

A prospective study of cancer incidence in a cohort examined for allergy

In order to assess the association between atopy and cancer risk, a cohort of 6593 skin-prick-tested patients was established. Among atopic subjects, no overall increased cancer risk was found, but the incidence of both breast cancer (standardized incidence ratio (SIR) 2.50, 95% CI 1.01–5.16) and malignant lymphomas (SIR 4.40, 95% CI 1.20–11.3) was significantly enhanced. Atopic subjects with asthma showed a decreased overall cancer risk (SIR 0.73, 95%, CI 0.27–1.60), as compared with the other asthmatic subjects (SIR 1.46, 95% CI 1.03–2.04). The cancer risk for subjects with rhinitis was near unity (SIR 1.11), irrespective of whether the subjects were atopic or not. An almost significant risk increase for cancer was observed among subjects with urticaria (SIR 1.70, 95% CI 0.99–2.80). Our results support neither the original hypothesis of an overall cancer protective effect of atopy, nor that of an opposite effect; rather, they strengthen the view that the association between atopic diseases and cancer is complex.     

Bacteremia associated with pressure ulcers: a prospective cohort study

The objective of this study is to evaluate the clinical and microbiological characteristics of bacteremia associated with pressure ulcers (BAPU) and factors associated with mortality. This study was a prospective observational cohort study of patients with BAPU at a teaching hospital between January 1984 and December 2015. Fifty-six episodes were included. The incidence of BAPU decreased from 2.78 cases per 10,000 hospital discharges in the period from 1984 to 1999 to 1.05 cases per 10,000 hospital discharges in the period from 2000 to 2015 (p <?0.001). In 20 cases (35.7%), the bacteremia was hospital-acquired, since it occurred more than 48 h after the hospital admission. The most frequent microorganisms isolated in blood culture were Staphylococcus aureus, Proteus spp., and Bacteroides spp. The bacteremia was polymicrobial in 14 cases (25.0%). Overall mortality was observed in 23 episodes (41.1%). The risk factors independently associated with mortality were hospital-acquired bacteremia (odds ratio [OR] 5.51, 95% confidence interval [95%CI] 1.24–24.40), polymicrobial bacteremia (OR 6.88, 95%CI 1.22–38.89), and serum albumin <23 g/L (OR 8.00, 95%CI 1.73–37.01). BAPU is an uncommon complication of pressure ulcers and is mainly caused by S. aureus, Proteus spp., and Bacteroides spp. In our hospital, the incidence of BAPU has declined in recent years, coinciding with the implementation of a multidisciplinary team aimed at preventing and treating chronic ulcers. Mortality rate is high, and hospital-acquired bacteremia, polymicrobial bacteremia, and serum albumin <?23 g/L are associated with increased mortality.     

Brain computer tomography in critically ill patients - a prospective cohort study

Background

The advantages of multi-detector computed tomography (MDCT) have made it the imaging modality of choice for some patients with suspected cardiothoracic disease, of which pulmonary embolism (PE) is an exponent. The aim of this study was to assess the incidence of PE in patients with clinical suspicion of acute PE using MDCT in a sub-Saharan setting, and to describe the demographic characteristics of these patients.

Methods

Consecutive records of patients who underwent MDCT pulmonary angiography for suspected acute PE over a two-year period at the Radiology Department of a university-affiliated hospital were systematically reviewed. All MDCT pulmonary angiograms were performed with a 16-detector computed tomography (CT) scanner using real-time bolus tracking technique. Authorization for the study was obtained from the institutional authorities.

Results

Forty-one MDCT pulmonary angiograms were reviewed of which 37 were retained. Of the 4 excluded studies, 3 were repeat angiograms and 1 study was not technically adequate. Twelve of 37 patients (32.4%) had CT angiograms that were positive for PE, of which 7 were males. The mean age of these patients was 47.6±10.5 years (age range from 33 to 65 years). Twenty five patients out of 37 (67.6%) had CT angiograms that were negative for PE. Eleven PE-positive patients (91.7%) had at least 1 identifiable thromboembolic risk factor whilst 5 PE-negative patients (20%) also had at least a thromboembolic risk factor. The relative risk of the occurrence of PE in patients with at least a thromboembolic risk factor was estimated at 14.4.

Conclusion

Acute PE is a reality in sub-Saharan Africa, with an increased likelihood of MDCT evidence in patients with clinical suspicion of PE who have at least a thromboembolic risk factor. The increasing availability of MDCT will help provide more information on the occurrence of PE in these settings.     

Anthroposophic medical therapy in chronic disease: a four-year prospective cohort study

Background  

The short consultation length in primary care is a source of concern, and the wish for more consultation time is a common reason for patients to seek complementary medicine. Physicians practicing anthroposophic medicine have prolonged consultations with their patients, taking an extended history, addressing constitutional, psychosocial, and biographic aspect of patients' illness, and selecting optimal therapy. In Germany, health benefit programs have included the reimbursement of this additional physician time. The purpose of this study was to describe clinical outcomes in patients with chronic diseases treated by anthroposophic physicians after an initial prolonged consultation.     

Surgical site infections following craniotomy focusing on possible post-operative acquisition of infection: prospective cohort study

Neurosurgery is characterized by a prolonged risk period for surgical site infection (SSI), mainly related to the presence of cerebrospinal fluid (CSF) drains. We aimed to examine factors associated with post-neurosurgical SSIs, focusing on post-operative factors. A prospective cohort study was conducted in a single center over a period of 18 months in Israel. Included were adult patients undergoing clean or clean-contaminated craniotomy, including craniotomies with external CSF drainage or shunts. SSIs were defined by the Centers for Disease Control and Prevention (CDC) criteria for healthcare-associated infections. All patients were followed up for 90 days and those with foreign body insertion for 1 year. We compared patients with and without SSI. A multivariable regression analysis for SSI was conducted including uncorrelated variables significantly associated with SSI. A total of 502 patients were included, with 138 (27.5 %) undergoing emergent or urgent craniotomy. The overall SSI rate was 5.6 % (28 patients), of which 3.2 % (16 patients) were intracerebral. Non-elective surgery, external CSF drainage/monitoring devices, re-operation, and post-operative respiratory failure were independently associated with subsequent SSI. External CSF devices was the only significant risk factor for intracerebral SSIs (p?<?0.001). Internal shunts or other foreign body insertions were not associated with SSIs. A phenotypically identical isolate to that causing the SSI was isolated from respiratory secretions prior to the SSI in 4/9 patients with microbiologically documented intracerebral SSIs. Patients with SSIs had longer hospital stay, poorer functional capacity on discharge, and higher 90-day mortality. We raise the possibility of post-operative infection acquisition through external CSF devices. Standard operating procedures for their maintenance are necessary.     

Staphylococcus aureus colonization during military service: a prospective cohort study

ObjectivesStaphylococcus aureus colonization leading to skin and soft-tissue infections (SSTI) are known challenges in crowded settings such as the military. The aim of the study was to establish and compare the prevalence of S. aureus colonization in recruits at enrolment and discharge after the first year of military service, and to investigate the prevalence of S. aureus SSTI.MethodsAll recruits entering first year of military service in January 2013 to be stationed at three garrisons in the northern part of Norway were invited to join this prospective cohort study. Swabs were taken from nose, throat and perineum. Staphylococcus aureus was identified using standard culturing methods. Methicillin resistance was determined by a cefoxitin disc diffusion test.ResultsOf the 923 eligible recruits, 512 were included at enrolment; 265/512 (52%) were also screened at discharge. Staphylococcus aureus colonization was high, and increased significantly during military service (166/265 versus 224/265, p < 0.001) mainly caused by increase in throat colonization alone or in combination with nasal colonization. All S. aureus isolates were susceptible to methicillin. SSTI was self-reported in 7/265 (3%) recruits, of which only one was confirmed by a military physician.ConclusionStaphylococcus aureus colonization increased during military service, but there were few confirmed reports of SSTI. Inclusion of throat swab provides important information as ∼20% of the recruits were only positive in their throat. Further analyses need to be performed to investigate if the increase in colonization is caused by specific S. aureus stains.     

Staphylococcus aureus colonization and acquisition of skin and soft tissue infection among Royal Marines recruits: a prospective cohort study

ObjectivesSkin and soft tissue infections (SSTIs) are a serious health issue for military personnel. Of particular importance are those caused by methicillin-resistant Staphylococcus aureus and Panton–Valentine leucocidin (PVL)-positive S. aureus (PVL-SA), as they have been associated with outbreaks of SSTIs. A prospective observational study was conducted in Royal Marine (RM) recruits to investigate the prevalence of PVL-SA carriage and any association with SSTIs.MethodsA total of 1012 RM recruits were followed through a 32-week training programme, with nose and throat swabs obtained at weeks 1, 6, 15 and 32. S. aureus isolates were characterized by antibiotic susceptibility testing, spa typing, presence of mecA/C and PVL genes. Retrospective review of the clinical notes for SSTI acquisition was conducted.ResultsS. aureus colonization decreased from Week 1 to Week 32 (41% to 26%, p < 0.0001). Of 1168 S. aureus isolates, three out of 1168 (0.3%) were MRSA and ten out of 1168 (0.9%) PVL-positive (all MSSA) and 169 out of 1168 (14.5%) were resistant to clindamycin. Isolates showed genetic diversity with 238 different spa types associated with 25 multi-locus sequence type (MLST) clonal complexes. SSTIs were seen in 35% (351/989) of recruits with 3 training days lost per recruit. SSTI acquisition rate was reduced amongst persistent carriers (p < 0.0283).ConclusionsNose and throat carriage of MRSA and PVL-SA was low among recruits, despite a high incidence of SSTIs being reported, particularly cellulitis. Carriage strains were predominantly MSSA with a marked diversity of genotypes. Persistent nose and/or throat carriage was not associated with SSTI acquisition. Putative person-to-person transmission within troops was identified based on spa typing requiring further research to confirm and explore potential transmission routes.