Predominance Of Gram-negative Bacilli Research Articles

Catheter-Related Bloodstream Infections among patients on maintenance haemodialysis: a cross-sectional study at a tertiary hospital in Ghana

BackgroundCatheter-Related Bloodstream Infections (CRBSIs) are notable complications among patients receiving maintenance haemodialysis. However, data on the prevalence of CRBSIs is lacking. This study was conducted to determine the prevalence and factors associated with CRBSIs among patients receiving haemodialysis in the renal unit of the largest tertiary hospital in Ghana.MethodsA hospital-based cross-sectional study was conducted on patients receiving maintenance haemodialysis via central venous catheters (CVC) between September 2021 and April 2022. Multivariate analysis using logistic regression was used to determine the risk factors that were predictive of CRBSI. Analysis was performed using SPSS version 23 and a p-value<0.05 was statistically significant.ResultsThe prevalence of CRBSI was 34.2% (52/152). Of these, more than half of them (53.9%(28/52)) had Possible CRBSI while 11.5% (6/52) had Definite CRBSI. Among the positive cultures, 62% (21/34) were from catheter sites whilst the rest were from peripheral blood. Gram-negative cultures made up 53% (18/34) of positive cultures with the rest being Gram positive cultures. Acinetobacter baumannii (33.3% (6/18)) was the commonest organism isolated among Gram-negative cultures whilst Coagulase negative Staphylococci (43.7% (7/16)) was the commonest organism isolated among Gram-positve cultures. Gram-negative bacilli were more predominant in this study making up 52.9% of the total bacteria cultured. Sex, duration of maintenance dialysis, underlying cause of End-stage kidney disease, mean corpuscular haemoglobin (MCH), neutrophil count and lymphocyte count were significantly predictive of CRBSI status (p<0.05).ConclusionThere was a high prevalence of CRBSI among patients undergoing haemodialysis. The commonest causative agent was Coagulase negative Staphylococci, however there was a predominance of Gram-negative bacilli as compared to Gram positive cocci. There is a need to set up infection surveillance unit in the renal unit to track CRBSI and put in place measures to reduce these CRBSI.

Investigating infectious outcomes in adult patients undergoing solid organ transplantation: A retrospective single-center experience, Paris, France.

This study described the demographic characteristics, clinical presentation, treatment, and outcomes of solid organ transplant recipients who were admitted to our center for infection. It also determined factors associated with a poor outcome, and compares early and late period infections. In this retrospective observational study, conducted at a tertiary care center in France between October 2017 and March 2019, infectious outcomes of patients with solid organ transplant where studied. A total of 104 patients were included with 158 hospitalizations for infection. Among these 104 patients, 71 (68%) were men. The median age was 59 years old. The most common symptoms on admission were fever (66%) and chills (31%). Lower respiratory tract infections were the most common diagnosis (71/158 hospitalizations). Urinary tract infections were frequently seen in kidney transplant recipients (25/60 hospitalizations). One or more infectious agents were isolated for 113 hospitalizations (72%): 70 bacteria, 36 viruses and 10 fungi, with predominance of gram-negative bacilli (53 cases) of which 13 were multidrug-resistant. The most frequently used antibiotics were third generation cephalosporins (40 cases), followed by piperacillin-tazobactam (26 cases). We note that 25 infections (16%) occurred during the first 6 months (early post-transplant period). Patients admitted during the early post-transplant period were more often on immunosuppressive treatment with prednisone (25/25 VS 106/133) (p = 0.01), mycophenolic acid (22/25 VS 86/133) (p = 0.03), presented for an urinary tract infection (10/25 VS 25/133) (p = 0.04) or a bacterial infection (17/25 VS 53/133) (p = 0.01). Patients with later infection had more comorbidities (57/83 VS 9/21) (p = 0.03), cancer (19/83 VS 0/21) (p = 0.04) or were on treatment with everolimus (46/133 VS 0/25) (p = 0.001). During 31 hospitalizations (20%), patients presented with a serious infection requiring intensive care (n = 26; 16%) or leading to death (n = 7; 4%). Bacteremia, pulmonary and cardiac complications were the main risk factors associated with poor outcome. Infections pose a significant challenge in the care of solid organ transplant patients, particularly those with comorbidities and intensive immunosuppression. This underscores the crucial importance of continuous surveillance and epidemiologic monitoring within this patient population.

Assessment of the Bacterial Pollution and Detection of Antibiotic Resistance Genes in Benin: Case of the Hydrographic Channel Complex Cotonou-Nokoué Lake.

The study aims to document the level of contamination of the aquatic ecosystem of the Cotonou-Lake Nokoué canal hydrographic complex by multidrug-resistant bacteria and their resistance genes. For this purpose, water samples were taken from several points of the complex and from the sediments at the depth of the lake. Samples of several species of freshly caught fish products from the lake were also collected. Bacteriological analyses were carried out according to the AFNOR standard (NF U: 47–100). The identification of the different bacterial species isolated was then carried out using the API 20E gallery and specific biochemical tests. The antibiogram of the strains was performed according to the recommendations of the EUCAST. Molecular characterization of the identified strains was carried out by searching for resistance and virulence genes. The results obtained revealed the presence of several bacterial species in water samples and in sediment and intestine samples of fishery products with a predominance of Gram-negative bacilli. The resistance profile of Gram-negative bacilli showed a total resistance to metronidazole (100%). 23% of the strains were also resistant to ciprofloxacin, 41% to amoxicillin, and 60% to aztreonam. Of the Gram-positive cocci identified, 66% was resistant to vancomycin, 7.5% to ciprofloxacin, 71% to erythromycin, and 22% to tetracycline. Regarding the genes sought, blaTEM (46%), blaSHV (24%), and blaCTX-M-15 (31%) were present in the genome of Gram-negative bacilli as resistance genes and fimH (41%) as virulence gene. As for Gram-positive cocci, the van B gene was completely absent. The van A was present at 6.25% in Staphylococcus aureus and mecA at 21.88 and 33.33%, respectively, in Staphylococcus aureus and coagulase-negative staphylococci strains. The high resistance of isolated bacterial strains is a matter of concern and calls for a rational use of antibiotics in order to avoid the transmission of antibiotic resistance from the environment to humans.

English

BACKGROUND Septicaemia is a leading cause of morbidity and mortality in neonates. Antimicrobial prescription for neonatal septicaemia (NS) should be wisely used depending on the regional spectra of infecting microbes and their antimicrobial resistance (AMR) patterns which vary over time, place and host factors. METHODS This was a descriptive cross-sectional study conducted from January 2017 to June 2017 among 102 cases of NS admitted in neonatal intensive care units (NICU). Demographic data of the concerned neonates was collected through a predesigned checklist. Blood collected from neonates was processed for culture and sepsis screen. Antimicrobial susceptibility testing was performed for the cultured isolates and phenotypic AMR patterns were observed. RESULTS Most of the studied neonates had subnormal birth weight (86). Blood culture showed predominance of gram-negative bacilli (GNB) among which Klebsiella pneumoniae was the most common followed by Burkholderia cepacia complex. Coagulase negative staphylococcus species (CoNS) was most numerous among the cultured gram-positive cocci (GPC). Candidemia of late onset was confirmed in 25 neonates. Early onset sepsis was predominantly caused by GNB (29 / 31) predominated by Klebsiella pneumoniae. Multi drug resistant (MDR) pathogens viz., extended spectrum beta-lactamase (ESBL) producing GNB, carbapenem resistant-GNB (CR-GNB) and methicillin resistant staphylococcus (MRS) phenotypes were notably prevalent. CONCLUSIONS Multidrug resistant microorganisms are notably prevalent in neonatal septicaemia. In clinically suspected very sick septicaemic neonates not showing much improvement with guideline-led empirical antimicrobial therapy, an early antibiogram guided change over to meropenem and amikacin or even to colistin in case of reported carbapenem resistance, is highly recommended. KEYWORDS Antimicrobial Resistance, Blood Culture, Multi Drug Resistance, Neonatal Septicaemia

Bacterial Infections in Patients with Liver Cirrhosis in an Internal Medicine Department

Background and Aims: Liver cirrhosis (LC) is the end stage of multiple processes that lead to hepatic failure and is the 10th most common cause of death in the Western world. Bacterial infections are one of the most important clinical problems in patients with LC, as their underlying immune status is compromised. Approximately 60% of bacterial infections in cirrhotic patients are community acquired (CA) and 40% are nosocomial. The most common infections in cirrhotic patients are spontaneous bacterial peritonitis (SBP) (25%), urinary tract infection (UTI) (20%), pneumonia (15%), bacteremia (12%), and cellulitis (2–11%). The aim of this study was to evaluate the most frequent infections in patients with LC and describe the evolution of the microbiology in these patients. Material and Methods: This is a retrospective analysis of 4 interspersed years (2008, 2010, 2012, and 2014) that included 372 patients. Demographic characteristics were evaluated, including gender, age, type of infection, bacteria resistance profile, antibiotic use, Child-Pugh-Turcotte and Model for End-Stage Liver Disease scores, and mortality rate. Results: The mean age of all patients enrolled in this study was 64.5 ± 12.2 years. Male patients were significantly more prevalent than female ones (72 vs. 28%). In the 4 analyzed years, the following numbers of infections occurred: 71 infections (49% CA and 51% nosocomial) in 2008; 86 infections (60.5% CA and 39.5% nosocomial) in 2010; 99 infections (56.6% CA and 43.4% nosocomial) in 2012; and 116 infections (70.7% CA and 29.3% nosocomial) in 2014. The most frequent infections were UTI (32.5%), respiratory tract infection (29.3%), SBP (26.1%), and cellulitis (6.2%). A microbiological agent was identified in 32.4, 59.3, 53.5, and 61.2% of infections in 2008, 2010, 2012, and 2014, respectively, with a predominance of gram-negative bacilli. In all series, a third-generation cephalosporin was the most frequent antibiotic used empirically. The majority of patients was in stage B (42.7%) of the Child-Pugh-Turcotte score, followed by stage C (39.3%) and stage A (18%). Mortality increased significantly over the years, from 7% in 2008 to 25% in 2014 (p = 0.016). Conclusions: The present study showed a high prevalence of bacterial infections in patients with LC. A high rate of suspicion is needed for an infectious process in these patients, and an appropriate antibiotic treatment can decrease the morbidity and mortality in cirrhotic patients.

Prevalence of common nosocomial organisms in surgical Intensive Care Unit in North India: A hospital-based study.

Background:Nosocomial infection presents with high mortality rate, and it remains a diagnostic and treatment challenge for health-care providers, with developing countries having the highest incidence and mortality rates.[1]Aim:The present study was undertaken to evaluate prevalence of commonly isolated nosocomial organisms in patients admitted in Surgical Intensive Care Unit (ICU) in Government Medical College Srinagar.Materials and Methods:The study was proposed to be conducted in surgical ICU of Shri Maharaja Hari Singh – a Tertiary Care Hospital in Jammu and Kashmir (India) from March 2015 to March 2016. The patients developing ICU infections within 48 h of admission in ICU or within 48 h of transfer from ICU were included in the study.Results:Forty patients showing different types of infections were included, 92 samples were collected which included 39.13%, 27.17%, 8.70%, 7.61%, 10.87%, and 6.52% blood, urine, swab, sputum, pus, and endotracheal tube (ETT) samples, respectively. From these samples, 27.78%, 76.0%, 87.5%, 71.43%, 80.0%, and 33.33% samples of blood, urine, swab, sputum, pus, and ETT, respectively, were found positive, i.e. showed the growth of microorganisms. A total of 10 types of microorganisms were isolated (Escherichia coli, Pseudomonas spp., Klebsiella spp., Acinetobacter spp., Staphylococcus aureus, Enterococcus, Enterobacter spp., Proteus spp., Citrobacter spp., and Candida spp.) from six types of samples among which maximum number of microorganisms were isolated from swab which was followed by blood and urine, while minimum number of microorganisms were isolated from ETT. Further, among ten microorganisms isolated, the highest percentage was recorded for Pseudomonas spp., which was followed by Klebsiella spp. and E. coli, while the lowest percentage was recorded for Proteus spp.Conclusion:There was a predominance of Gram-negative bacilli than Gram-positive bacilli.

Scanning Electron Microscopic Biofilm Grading and Ventilator Associated Pneumonia in Relation to Duration of Intubation

Background: Ventilator associated pneumonia (VAP) accounts for 7-70% of infections in intensive care units (ICUs) leading to increase in hospitalization, mortality and cost. Endotracheal tube (ETT) is a risk factor for developing VAP caused by biofilm producing organisms resistant to antimicrobial agents. This study aimed to determine guidelines for ETT extubation through detection of biofilm formation and development of VAP. Objectives: Our aim was to assess biofilm formation on the luminal surface of ETTs in intubated patients in ICU in relation to duration of intubation bacteriologically and morphologically using Scanning Electron Microscope (SEM). Antimicrobial resistance and VAP development were also studied. Methodology: Our work was conducted on 20 ETTs divided into two groups: Group (1); 8 patients with ETTs<5 days, and group (2); 12 patients with ETTs of 5-12 days. Culture of the interior of the ETTs, identification of bacterial species, antibiotic susceptibility and presence with staging of biofilm into 3 grades by SEM were performed. Results: A highly significant relationship was observed between the duration of intubation and biofilm grading (p value <0.001). Also, the duration of intubation and VAP development were significantly correlated (p<0.001). A highly significant relationship was observed between VAP development and biofilm grading by SEM (p<0.001). A moderate significant relationship was found between VAP development and prognosis of patients (p<0.02). It was also observed that prolonged intubation was associated with prevalence of polymicrobial colonization with the predominance of Gram negative bacilli. Furthermore, a moderate significant relationship was observed between antimicrobial resistance and both biofilm grading and duration of intubation (p<0.02). Conclusion: Biofilm formation and grading as well as bacterial colonization with multidrug-resistant (MDR) bacteria were time dependent in patients on mechanical ventilation in ICU which may enhance their morbidity and mortality rates. Also a role of ETT biofilm is emphasized in the pathogenesis and prognostic outcome of VAP in patients intubated for a prolonged period. Accordingly, we recommend that ETT should be exchanged every 4 days to avoid such morbidity and mortality consequences.

Bacteriological profile and antimicrobial susceptibility in surgical site infection in elective abdominal surgeries

Background: Surgical site infection (SSI) represents a substantial burden of disease for patients and health services. A common scenario in developing countries is that though hospital infection control programme is in place but surveillance or feedback of SSI rates is usually not implemented. Therefore, an effective surveillance programme for SSI should be a critical component of any hospital infection control programme. Methods: This study provided documented data on SSI in our hospital. The study was carried on 100 patients admitted for elective abdominal surgery. The overall infection rate in our study was 6%. There was predominance of gram negative bacilli. Results: The gram positive isolates showed a high level of resistance against first, second and third generation cephalosporins. The gram negative isolates showed resistance to penicillin, ampicillin and amoxicillin clavulanate, cephalosporins and quinolones. Conclusions: The overall SSI rate in our hospital was comparatively low as compared to other Indian hospital as well as hospitals in other developing countries, indicating that a satisfactory hospital infection control programme was in place.

Predominance of Gram-negative bacilli among patients with catheter-related bloodstream infections

We evaluated changes in the epidemiology of catheter-related bloodstream infections (CRBSIs) between 1996 and 2012 in a tertiary care centre in Israel. The cohort included 1754 episodes of CRBSI. The incidence of CRBSIs decreased throughout the study period, whereas 30-day mortality following bacteraemia increased. There was a linear shift toward predominance of Gram-negative bacilli throughout the study period (p for trend <0.001). In 1996, 68% (68/100) of CRBSIs were caused by Gram-positive cocci, whereas in 2012 77.8% (28/26) were caused by Gram-negative bacilli. The shift towards Gram-negative CRBSIs and the associated mortality mandates that empirical treatment for CRBSIs be directed by local epidemiology.

Concurrent Bloodstream Infections in Infants with Necrotizing Enterocolitis

To determine the incidence, microbiology, risk factors, and outcomes related to bloodstream infections (BSIs) concurrent with the onset of necrotizing enterocolitis (NEC). We performed a retrospective review of all cases of NEC in a single center over 20 years. BSI was categorized as "NEC-associated" if it occurred within 72 hours of the diagnosis of NEC and "post-NEC" if it occurred >72 hours afterwards. Demographics, hospital course data, microbiologic data, and outcomes were compared via univariate and multivariate analyses. NEC occurred in 410 infants with mean gestational age and birth weight of 29 weeks and 1290 g, respectively; 158 infants were diagnosed with at least one BSI; 69 (43.7%) with NEC-associated BSI, and 89 (56.3%) with post-NEC BSI. Two-thirds of NEC-associated BSI were due to gram-negative bacilli compared with 31.9% of post-NEC BSI (OR: 4.27; 95% CI: 2.02, 9.03) and 28.5% of all BSI in infants without NEC (OR: 5.02; 95% CI: 2.82, 8.96). Infants with NEC-associated BSI had higher odds of requiring surgical intervention (aOR: 3.51; 95% CI: 1.98, 6.24) and death (aOR: 2.88; 95% CI: 1.39, 5.97) compared with those without BSI. BSI is a common, underappreciated complication of NEC occurring concurrent with the onset of disease and afterwards. The microbiologic etiology of NEC-associated BSI is different from post-NEC and late-onset BSI in infants without NEC with a predominance of gram-negative bacilli. Infants with NEC-associated BSI are significantly more likely to die than those with post-NEC BSI and NEC without BSI.

Febrile neutropenia studies in Brazil - treatment and cost management based on analyses of cases

The management of neutropenia is a challenge in the clinical practice. It is known since the 1960s that risk of infection is associated with the intensity and duration of neutropenia(1). Neutropenic patients with an infection usually present incomplete signs and symptoms considering the severity of the condition. Thus, rubor, erythema and pustules may not be seen in neutropenia associated with a cutaneous infection, just as pulmonary infections may fail to present classical signs and symptoms such as cough, dyspnea and characteristic physical examination findings(2). Sometimes the only sign found is fever. Studies published in the 1970s have taught us that the quick administration of broad-spectrum antimicrobial agents dramatically reduces mortality from 50-90% to 10-40% within the first 72 hours of treatment(3-5). It is also known that the microbial isolation rate is low, and that there is a predominance of gram-negative bacilli. The use of antibiotics for gram-positive cocci should be adopted in cases of clear-cut risk situations such as mucositis, evident infection of a central venous catheter, hemodynamic instability and cutaneous infections(6). As of the 1980s, several studies on febrile neutropenia were performed in an attempt to differentiate risk groups for severe complications and death. The studies started with Talcott et al., who showed that patients with neutropenia undergoing chemotherapy and fever at home, without comorbidities and with the oncological disease under control, presented a low risk(7,8). In 2000, a study that standardized the risk evaluation of patients with febrile neutropenia undergoing chemotherapy was published. The index of the Multinational Association for Supportive Care of Cancer (MASCC) standardized the risk evaluation in febrile neutropenia based on clinical parameters; this evaluation that took into account the intensity of symptoms, hypotension, presence of previous fungal infection, dehydration, age and home fever was widely tested and recognized as one of the best methods to screen patients with febrile neutropenia(9). In Brazil, there are few studies that applied the MASCC index(10,11), but the mortality rate among high- and low-risk febrile neutropenia groups is notorious (Table 1). Table 1 Mortality rate among high-risk and low-risk febrile neutropenia groups Differentiating the risk groups is important because it can lower the costs of the treatment of febrile neutropenia. Pharmacoeconomic studies have estimated that the cost of each febrile neutropenia event varies between US$ 2000 and US$ 11000. According to Canadian and British studies, 25.8% of this cost is related to antibiotics and 16.4% to complementary tests. It is further estimated that about US$ 5000 can be saved per febrile neutropenia episode when the patient can be discharged early and followed up as an outpatient. The use of orally instead of intravenously administered antibiotics reduces the cost by about 80%(15). The article published in this journal, Neutropenic patients and their infectious complications at a University Hospital(16), reports on a cross-sectional study of the universe of neutropenic inpatients with infections in a general hospital. This matter needs to be further studied, and Brazilian multicentric prospective studies need to be performed given the importance of studies like this in reconfirming the relevance of the MASCC index in respect to mortality. The profile of the microbial agents isolated and their sensitivity profile help our understanding of febrile neutropenia cases and improves treatment provided to patients and a better management of the costs.

Etiologic agents in 54 consecutive febrile neutropenia (FN) isolates in a general hospital in Medellín, Colombia.

e19604 Background: The etiology of FN is well established in the US and the EU. Less is known about it in Colombia. This cohort attempts to fill this void. Methods: We collected prospectively the information on all FN cases with an established etiology that were admitted to the Clínica SOMA (A 160 bed-facility in Medellín, Colombia) from September 2010 to October 2011. FN was defined as the coexistence of an absolute neutrophile count (ANC) &lt;500 and a temperature &gt;38.3 degrees Celsius following cytotoxic chemotherapy for cancer. Results: Fifty four cases of FN with known etiology were found. Twenty four in males and 30 in females. Age range from 16 to 73 years-old (median: 42). Acute lymphoblastic leukemia was the underlying diagnosis in 16 (30%), acute myelogenous leukemia in 13 (24% ), and non-Hodgkin’s lymphoma in 11 (20%). HyperCVAD (with o without rituximab), IdaFlag, bortezomib and HiDAC account for 17 (31%), 12 (22%), 7 (13%), and 5 (9%) cases, respectively. FN occurred 2 to 32 days after chemotherapy (average of 10 days). In 20 (37%) cases ANC on admission was 0, and the average ANC on admission was 120. In 51 cases germs were isolated in the blood (94%). Gram-negative bacilli were isolated in 38 cases (76%), S. aureus in 4 (7%), Candidemia was established in 4 patients (2 with C. krusei and 2 with C. parapsilosis). Pulmonary aspergillosis was established in one case. Of note, two cases of hospital-acquired Legionella pneumophila were found (Table). All patients recovered to non-neutropenic ANC with resolution of the infections. No deaths due to FN occurred in this group of patients. Conclusions: In this cohort from Colombia we found a large predominance of gram-negative bacilli and the isolation of L. Pneumophilla, an unusual pathogen in FN. This pattern differs from the usual germ mix reported in other series. [Table: see text]

Study of aerobic bacterial isolates and their antibiotic susceptibility pattern in chronic suppurative otitis media

Background : Chronic suppurative otitis media (CSOM) is a disease of multiple etiology and its importance lies in its chronicity and dreaded complications. Both Gram positive and negative organisms are responsible for infection of the middle ear. Due to advent of newer and sophisticated antibiotics, the microbiological flora is changing constantly. This requires a reappraisal of the flora in CSOM and their in vitro antibiotic sensitivity pattern in cases of CSOM, which do not respond to local antibiotics. The frequent presence of CSOM in general practice and its poor response to the routine treatment are the factors responsible for undertaking this study. Materials and Methods : One hundred and twenty six patients with CSOM were prospectively studied. They had chronic ear discharge and had not received antibiotics for the previous five days. Swabs were taken and cultured for bacteria. The standard method of isolation and identification was followed. Antimicrobial susceptibility of the bacterial isolates was performed by Kirby-Bauer's disc diffusion method. Results: Analysis of bacterial flora of the present study showed predominance of Gram negative bacilli (69.84%). The highest incidence (45.24%) was that of Pseudomonas aeruginosa followed by Staphylococcus aureus (22.22%). Amikacin was found to be the most effective drug. Conclusion: This study suggests that the common etiological agents for CSOM were Pseudomonas aeruginosa followed by Staphylococcus aureus . Amikacin was found to be the drug of choice.

A Method for Making Carbohydrate Serum Broth of Constant Composition for use in the Study of Streptococci

very markedly the development of the streptococci. It was often observed that exudate from appendiceal and other peritonitis cases showed in direct smears a mixture of Gram-negative bacilli and Grampositive streptococci. Part of this material was added to plain broth and part to serum broth, and on examination of the growth in twentyfour hours or less the microscopical pictures from the two media were very different. That from the plain broth showed a predominance of Gram-negative bacilli with very few Gram-positive cocci, while the smear from serum broth showed what often appeared to be a pure culture of streptococci. From feces, one obtains practically the same results, that is, in the serum broth, the streptococci developing are numerous, while in plain broth they are almost absent.